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Ethnopharmacological Relevance: Zimbabwe is a key biodiversity domain in sub-Saharan Africa and ethnoveterinary medicines play an integral role in livestock health. However, knowledge on whether plants are used by only a small proportion of people or whether similar uses exist in different communities and in a more regional context is incompletely documented., Aim of the Study: Firstly, the study documented plant-based complementary medicines used for managing goat ailments. Secondly, culturally important medicinal plant species with highest use-reports (UR) as well as botanical and therapeutic consistency were computed. Thirdly, details on whether similar ethnobotanical practices exist in different communities as an indicator of information exchange were explored., Materials and Methods: A total of 200 informants from Gutu, Chikomba, Murewa and Mwenezi districts of Zimbabwe were interviewed. Plant identification was done at the National Herbarium and Botanic Gardens of Zimbabwe. Use-reports were generated and subjected to analysis using Analysis of Variance (ANOVA) in IBM SPSS statistical software., Results: The impact of parasites and diseases was ranked as the major goat production constraint. A total of 160 homemade remedies were documented, 151 of which comprised a single plant species (Homemade Single Species Herbal Remedy Reports, HSHR). The 151 HSHR prepared using 75 plant species belonging to 34 families referred to 401 UR. The foremost used medicinal plant species were from the Fabaceae family (28 HSHR, 19%). Cassia abbreviata was the most cited plant species (6 HSHR, 4%). The category of ecto- and endoparasites had the highest number of UR out of a total of 9 categories (136 UR, 34%). The most frequently used plant species for this category were Solanum campylacanthum (8 UR, 6%) and Strychnos spinosa (6 UR, 4%). Almost similar numbers of UR were computed across communities for 6 disease categories. Nine different combinations (9 HR, 9 UR) comprising mostly of three plant species were reported for various ailments. Baccharoides adoensis and Terminalia sericea were often reported in these combinations for January disease. Highest levels of therapeutic consistency were computed for Aloe vera and Lippia javanica against ectoparasites (10 out of 24 local studies). Interestingly, 28 new medicinal plant species were documented for the first time in Zimbabwe. Again, these were mostly used for ecto-and endoparasites (8 plant species, 29%)., Conclusions: Ethnoveterinary medicines play a pivotal role in management of livestock ailments in rural communities of Zimbabwe. However, attention is warranted to ensure transparency in use practices, as well as to conserve and scientifically validate culturally important medicinal plant species such as Aloe vera and Lippia javanica., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.)

Climate change and human activities severely impact the viability of plants and ecosystems, threatening the environment, biodiversity, and the sustainable development of plant-based products. Biotic and abiotic (ecosystem) determinants affect species distribution and long-term survival, which in turn influence the quality of plants used as herbal medicines and other high-value products. In recent decades, diverse anthropogenic impacts have significantly affected these quality aspects. Climate change, excessive plant exploitation, habitat loss, species vulnerability, and other factors have adversely affected the growth, reproduction, and adaptation of species populations, as well as the quality and volume of primary plant materials supplied to pharmaceutical markets. Despite these growing challenges, there is limited knowledge of potential strategies to prevent or mitigate these impacts, particularly for vulnerable species collected from the wild or harvested from traditional production systems. Hence, effective strategies for preserving and increasing plant populations are urgently needed. In this study, we propose a new framework including the main sustainability factors to better understand and address the vulnerability of a species, hence mitigate the impact of climate change. We assess the applicability of our proposed framework via seven case studies of vulnerable species (i.e., Aquilaria malaccensis Lam., Boswellia sacra Flück., Crocus sativus L., Panax quinquefolius L., Pilocarpus microphyllus Stapf ex Wardlew., Rhodiola rosea L., and Warburgia salutaris (G.Bertol.) Chiov.) from main biogeographic realms, all widely used as medicinal plants. These species present various challenges related to the sustainability of their use, impacting their current and future status locally and globally. Their economic importance, combined with rising demands and specific risks of overexploitation, are also key factors considered here. The suggested framework for the sustainability of medicinal and other high-value plant-based products in the phytopharmaceutical industry emphasises strategies that promote conservation and sustainable resource use. It can also be adapted for other vulnerable species requiring urgent attention., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2025 Mykhailenko, Jalil, McGaw, Echeverría, Takubessi and Heinrich.)

Oxidative stress is a key factor that activates several transcription factors and mediators involved in the inflammatory pathways responsible for the pathogenesis of many chronic diseases. Targeting the expression of these mediators represents a promising approach to preventing these diseases. Cassinopsis ilicifolia leaf infusion is traditionally used for treating conditions such as inflammation and pain relief. Thus, the present study assessed the antioxidant and anti-inflammatory activities of the hydroethanolic leaf extract of C. ilicifolia using in vitro and cell-based assays. As a result, C. ilicifolia extract exhibited the highest DPPH • and ABTS •+ radical scavenging potential. At the same time, it weakly scavenged the Fe 3+ -TPTZ radical up to 200 µg/mL, thus suggesting a different antioxidant mechanism triggered during each assay. Additionally, C. ilicifolia extract inhibited NO production and 15-LOX activity with IC 50 values of 21.10 µg/mL and 40.28 µg/mL, respectively. Further, C. ilicifolia extract was found to strongly inhibit ROS production in LPS-activated RAW 264.7 cells, and the study of its mechanism of action showed that it exerts its anti-inflammatory effect by downregulating the expression of inflammatory mediators such as IL-1β, TNF-α, and COX-2. Overall, C. ilicifolia extract showed consistent potency in all assays, and the analysis of its phytochemical profile led to the identification of 30 compounds, among which the most abundant were secologanic acid (1), chlorogenic acid (3CQA) (2), monotropein (3), chlorogenic acid (5CQA) (4), geniposidic acid (5), rutin (6), quercetin 3-galactoside (7), astragalin-7-rhamnoside (8), and minecoside (9) that are possibly responsible for its anti-inflammatory and antioxidant activities. Therefore, our findings suggested the potential use of C. ilicifolia as an alternative source for developing plant-based products against oxidative stress and inflammation-related conditions.

The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural products drug discovery, which previously led to the discovery of rifamycins, is a valuable approach in this endeavor. Against this backdrop, we set out to investigate the in vitro antimycobacterial properties of medicinal plants from Ghana and South Africa, evaluating 36 extracts and their 252 corresponding solid phase extraction (SPE) generated fractions primarily against the non-pathogenic Mycobacterium smegmatis and Mycobacterium aurum species. The most potent fraction was further evaluated in vitro against infectious M. tuberculosis strain. Crinum asiaticum (bulb) (Amaryllidaceae) emerged as the most potent plant species with specific fractions showing exceptional, near equipotent activity against the non-pathogenic Mycobacterium species (0.39 µg/ml ≤ MIC ≤ 25 µg/ml) with one fraction being moderately active (MIC = 32.6 µg/ml) against M. tuberculosis. Metabolomic analysis led to the identification of eight compounds predicted to be active against M. smegmatis and M. aurum. In conclusion, from our comprehensive study, we generated data which provided an insight into the antimycobacterial properties of Ghanaian and South African plants. Future work will be focused on the isolation and evaluation of the compounds predicted to be active., (© 2024. The Author(s).)

Background: Harungana madagascariensis (HM) and Psorospermum aurantiacum (PA), used traditionally for skin care, have been reported to upregulate the expression of intracellular antioxidant genes, thereby preventing melanoma and protecting fibroblast cell lines from Ultraviolet B (UVB)-induced intracellular oxidative stress., Aims: This investigation aimed to identify major compounds in bioactive fractions using bioassay- guided fractionation., Methods: The anti-inflammatory effect of fractions was determined by measuring their inhibitory activity on 15-lipoxygenase and nitric oxide (NO) in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. Additionally, the anti-aging efficacy of the fractions was determined by assessing the expression of markers for the aging process, i.e., expression of tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1), procollagen type-1 (COL1A1), and matrix metalloproteinase- 1 (MMP-1) in UVB-induced photoaging in skin cell-lines. Furthermore, UHPLCMS- based identification of the bioactive compounds from the most prominent fraction was also carried out., Results: Hexane fraction of HM significantly inhibited (p <0.05) the 15-lipoxygenase (IC50 = 46.80 μg/mL) and NO production (IC50 = 66.55 μg/mL), whereas hexane fraction of PA was effective (p <0.05) in inhibiting 15-lipoxygenase activity (IC50 = 27.55 μg/mL). Furthermore, the hexane fraction of HM and methanol fraction of PA were significantly effective (p <0.05) in reverting the UVB-mediated altered expressions of MMP-1, TYR, TRP-1, and COL1A1. Furthermore, hexane fraction of HM revealed the presence of harunganin and betulinic acid, whereas vismion D, vismin, kenganthranol B, and bianthrone 1a were identified from the methanol fraction of PA., Conclusion: Overall, the hexane fraction of HM and methanol fraction of PA displayed effective anti-aging activities, with additional anti-inflammatory effects., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Secondary metabolites were isolated using chromatographic techniques after being extracted sequentially from the roots of Artemisia afra using organic solvents such as ethanol, ethyl acetate, dichloromethane, and n-hexane. The isolated compounds were evaluated for anti-fungal, anti-bacterial, and cytotoxicity activities. Spectroscopic techniques, including Nuclear Magnetic Resonance (NMR), Fourier transform infrared (FTIR), and liquid chromatography-mass spectrometry (LC-MS), were used to elucidate the structures of the isolated compounds. The phytochemical investigation of A. afra led to the isolation of eight ( A - H ) compounds which were identified as 3 β -taraxerol ( A ), 3 β -taraxerol acetate ( B ), dodecyl- p -coumarate ( C ), ferulic acid ( D ), scopoletin ( E ), sitosterol-3- O - β - D -glucopyranoside ( F ), 3,5-di- O -feruloylquinic acid ( G ) and Isofraxidin-7- O - β - D -glucopyranoside ( H ) based on spectroscopic data. Compounds A , B , C , F , G , and H are known but were isolated for the first time from the roots of A. afra . The isolated compounds and extracts from A. afra exhibited good anti-fungal and anti-bacterial activity with dichloromethane and ethyl acetate crude extracts (0.078 mg/mL) and compound E (62.5 µg/mL) showed good activities against Escherichia coli . Compounds C and F also showed good activity against Enterococcus faecalis with minimum inhibitory concentration (MIC) values of 62.5 and 31.25 µg/mL, respectively. Extracts and compounds ( A - H ) exhibited anti-fungal and anti-bacterial properties and showed no toxicity when tested on Vero monkey kidney (Vero) cells.

Black locust ( Robinia pseudoacacia L.), an invasive tree in Europe, commonly known for its negative impact on biodiversity, is a rich source of phenolic compounds recognized in traditional medicine. Since the metabolite profile depends on the environment and climate, this study aimed to provide the first LC-MS phytochemical screening of the black locust from the Istria region (Croatia). The compounds were extracted from leaves and flowers with 70% ethanol and 80% methanol. Total phenolics (TP) and flavonoids (TF), as well as antioxidant capacity (AC) measured by ABTS (17.49-146.41 mg TE/g DW), DPPH (24.67-118.49 mg TE/g DW), and FRAP (7.38-77.53 mg TE/g DW) assays, were higher in leaf than in flower extracts. Higher TP and total non-flavonoid (TNF) values were displayed in ethanolic than in methanolic extracts. In total, 64 compounds were identified, of which flavonols (20) and hydroxycinnamic acid derivatives (15) were the most represented. Flavanols such as catechin dominated in leaf extracts, followed by flavonols, with kaempferol glucuronyl rhamnosyl hexosides as the main compound, respectively. Flower extracts had the highest share of flavones, followed by ellagitannins, with luteolin dirhamnosyl hexosides and vescalagin, respectively, being predominant. The extracts had good quorum sensing, biofilm formation prevention, and eradicating capacity. The results provided new insights into the phytochemical properties of R. pseudoacacia as the first step toward its potential pharmaceutical use.

Background: Sarcocephalus pobeguinii (Hua ex Pobég) is used in folk medicine to treat oxidative-stress related diseases, thereby warranting the investigation of its anticancer and anti-inflammatory properties. In our previous study, the leaf extract of S. pobeguinii induced significant cytotoxic effect against several cancerous cells with high selectivity indexes towards non-cancerous cells. Aim: The current study aims to isolate natural compounds from S. pobeguinii , and to evaluate their cytotoxicity, selectivity and anti-inflammatory effects as well as searching for potential target proteins of bioactive compounds. Methods: Natural compounds were isolated from leaf, fruit and bark extracts of S. pobeguinii and their chemical structures were elucidated using appropriate spectroscopic methods. The antiproliferative effect of isolated compounds was determined on four human cancerous cells (MCF-7, HepG2, Caco-2 and A549 cells) and non-cancerous Vero cells. Additionally, the anti-inflammatory activity of these compounds was determined by evaluating the nitric oxide (NO) production inhibitory potential and the 15-lipoxygenase (15-LOX) inhibitory activity. Furthermore, molecular docking studies were carried out on six putative target proteins found in common signaling pathways of inflammation and cancer. Results: Hederagenin ( 2 ), quinovic acid 3-O-[α-D-quinovopyranoside] ( 6 ) and quinovic acid 3-O-[β-D-quinovopyranoside] ( 9 ) exhibited significant cytotoxic effect against all cancerous cells, and they induced apoptosis in MCF-7 cells by increasing caspase-3/-7 activity. ( 6 ) showed the highest efficacy against all cancerous cells with poor selectivity (except for A549 cells) towards non-cancerous Vero cells; while ( 2 ) showed the highest selectivity warranting its potential safety as a chemotherapeutic agent. Moreover, ( 6 ) and ( 9 ) significantly inhibited NO production in LPS-stimulated RAW 264.7 cells which could mainly be attributed to their high cytotoxic effect. Besides, the mixture nauclealatifoline G and naucleofficine D ( 1 ), hederagenin ( 2 ) and chletric acid ( 3 ) were active against 15-LOX as compared to quercetin. Docking results showed that JAK2 and COX-2, with the highest binding scores, are the potential molecular targets involved in the antiproliferative and anti-inflammatory effects of bioactive compounds. Conclusion: Overall, hederagenin ( 2 ), which selectively killed cancer cells with additional anti-inflammatory effect, is the most prominent lead compound which may be further investigated as a drug candidate to tackle cancer progression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Mfotie Njoya, Ndemangou, Akinyelu, Munvera, Chukwuma, Mkounga, Mashele, Makhafola and McGaw.)

Uncomplicated malaria is effectively treated with oral artemisinin-based combination therapy (ACT). Yet, there is an unmet clinical need for the intravenous treatment of the more fatal severe malaria. There is no combination intravenous therapy for uncomplicated due to the nonavailability of a water-soluble partner drug for the artemisinin, artesunate. The currently available treatment is a two-part regimen split into an intravenous artesunate followed by the conventional oral ACT . In a novel application of polymer therapeutics, the aqueous insoluble antimalarial lumefantrine is conjugated to a carrier polymer to create a new water-soluble chemical entity suitable for intravenous administration in a clinically relevant formulation . The conjugate is characterized by spectroscopic and analytical techniques, and the aqueous solubility of lumefantrine is determined to have increased by three orders of magnitude. Pharmacokinetic studies in mice indicate that there is a significant plasma release of lumefantrine and production its metabolite desbutyl-lumefantrine (area under the curve of metabolite is ≈10% that of the parent). In a Plasmodium falciparum malaria mouse model, parasitemia clearance is 50% higher than that of reference unconjugated lumefantrine. The polymer-lumefantrine shows potential for entering the clinic to meet the need for a one-course combination treatment for severe malaria., (© 2023 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.)

Ethnopharmacological Relevance: Monsonia angustifolia is traditionally used to treat anthrax, heartburn, diarrhea, eye infections and hemorrhoids. Dodonaea angustifolia is frequently used as a treatment for dental pain, microbial infections and jungle fever. The two plant species were selected due to the presence of secondary metabolites such as coumarins, flavonoids, terpenoids, saponins and polyphenolics from the crude extracts, which exhibit pharmacological significance. The pure isolated compounds from the crude extracts are known for their diverse structures and interesting pharmacophores., Aim: To isolate and identify antibacterial and antifungal chemical constituents from Monsonia angustifolia and Dodonaea angustifolia plant extracts and evaluate the cytotoxicity of pure compounds from the crude extracts., Materials and Methods: Extractives from M. angustifolia and D. angustifolia plants were isolated using chromatographic techniques and structures were elucidated based on NMR, IR and MS spectroscopic techniques. A microplate serial dilution method was used to evaluate the antibacterial activity of extracts and pure compounds against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and antifungal activity against Candida albicans and Cryptococcus neoformans. The cytotoxicity was determined using the 3-(4, 5-dimethylthiazol)-2, 5-diphenyl tetrazolium bromide (MTT) assay., Results: The dichloromethane, ethyl acetate and methanol crude extracts from the plants exhibited significant inhibition of microbial growth. The phytochemical investigation of these active crude extracts led to the isolation of five pure active compounds, 5-methoxyjusticidin A (1), cis-phytyl diterpenoidal fatty acid ester (2), stigmasterol (3), β-sitosterol (4) and 5-hydroxy-7,4'-dimethoxyflavone (5). Stigmasterol (3) showed good antifungal activity against Cryptococcus neoformans with a minimum inhibition concentration (MIC) of 25 μg/mL and Candida albicans (MIC = 50 μg/mL)., Conclusion: Compounds (1-5) isolated from Monsonia angustifolia and Dodonaea angustifolia showed antibacterial and antifungal activities and were non-toxic against Madin-Darby canine kidney (MDCK) cells and VERO monkey kidney (VERO) cells., Competing Interests: Declaration of competing interest Authors declare no competing interests., (Copyright © 2022. Published by Elsevier B.V.)

Rhynchosia minima, commonly known as jumby bean, is used as a remedy for respiratory ailments in various parts of the world. It is also used by South African traditional healers to treat heart or chest pain. This study aimed to investigate the bioactive constituents of the leaf extracts of R. minima against selected fungal isolates that have been identified as risk factors in respiratory illness. Rhynchosia minima leaves were extracted sequentially using hexane, dichloromethane, ethyl acetate and methanol in increasing order of polarity. The extracts were subjected to repeated chromatographic techniques, for phytochemical isolation. The extracts and isolated compounds were screened against Candida albicans and Cryptococcus neoformans by determining the minimum concentration that inhibited fungal growth. Six flavonoids, one norisoprenoid and one cyclitol were isolated and characterized by 1D and 2D NMR and HR-ESI-MS. The extracts obtained in the study had moderate to weak antifungal activities, with MICs ranging from 312.5 to 1250.0 μg/mL against both fungi. Four isolated compounds were also screened, with two of them exhibiting activity against C. albicans (MIC=6.25 μg/mL) that was comparable to amphotericin B, the positive control. These two compounds also had better antifungal potential against C. neoformans with an MIC=6.25 μg/mL, compared to the MIC of 12.5 μg/mL of amphotericin B. Seven of the eight isolated compounds were obtained from the extracts of Rhynchosia minima for the first time. Two of the isolated compounds demonstrated activity comparable or superior to amphotericin B activity. The notable potency displayed by these compounds warrants further investigation on their development as antifungal agents., (© 2022 The Authors. Chemistry & Biodiversity published by Wiley-VHCA AG, Zurich, Switzerland.)

Apoptosis of germ cells is an important feature of spermatogenesis, as this process allows the removal of excess germ cells from testicular tissue. This is crucial to control the number of germ cells that can be supported and nourished by the Sertoli cells. It has been established that up to 75 % of germ cells are lost during the development of spermatogonia. In this process, germ cells with defective genes are removed. Also, apoptosis regulates homeostasis of testicular tissue by maintaining a balance between germ cell proliferation and cell death. This is necessary as it guarantees normal spermatogenesis. Apoptosis also occurs during maturation divisions of spermatocytes and spermatids but albeit to a lesser extent. Several factors, known pro-apoptotic proteins, play a critical role in the process of apoptosis. The most vital pro-apoptotic proteins are caspase-3, B-cells lymphoma 2 (Bcl2), truncated BH3 interacting death domain (tBID), tumor suppressor protein (p53), and Bcl-2 associated protein (BAX). Execution of apoptosis may be triggered by either an extrinsic or an intrinsic pathway. The extrinsic pathway is initiated by death receptors and death ligands. Death receptors trigger pro-apoptotic proteins such as caspase-3 for the execution of apoptosis. The intrinsic pathway, on the other hand, is triggered by nutrient deprivation, stress, or DNA damage, which in turn activates Bcl2 families of pro-apoptotic proteins that foster apoptosis. The present review focuses on pro-apoptotic proteins and their mechanisms of action, with special emphasis on their involvement in germ cell apoptosis in the testicular tissues of mammalian and avian species., Competing Interests: Declaration of Competing Interest The authors declare that there are no competing interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Selenium (Se) is an essential trace nutrient for humans and animals owing to its role in redox regulation, thyroid hormone control factors, immunity, inflammatory reactions, brain activities, and carbohydrate regulation. It is also important to support muscle development, as well as for reproductive and cardiovascular well-being. Furthermore, sulfur is known to be a healing element, due to the remarkable function of specialized and secondary S-containing compounds. The scope of the current study was to determine the impact of Se and S enrichment on the secondary metabolite accumulation and antibacterial and NO inhibition activities in green and red leaf lettuce (V1 and V2, respectively). The plants were grown in a hydroponic system supplied with different S concentrations (S0: 0, S1: 1 mM and S2: 1.5 mM K 2 SO 4 ) via the nutrient solution and foliar-applied varying levels of Se (0, 0.2 and 2.6 µM). Electrospray ionization-quadrupole time-of-flight mass spectrometry (ESI-QTOF/MS) combined with ultra-performance liquid chromatography (UPLC) was used to identify the secondary metabolites in green and red lettuce. The results indicated that extracts of the biofortified lettuce were not cytotoxic to Vero kidney cells at the highest concentration tested of 1 mg/mL. The ESI/MS of the tentatively identified metabolites showed that the response values of 5- O -caffeoylquinic acid, cyanidin 3- O -galactoside, quercetin 3- O -(6''-acetyl-glucoside) and quercetin 3- O -malonylglucoside were induced synergistically under higher Se and S levels in red lettuce plants. The acetone extract of red lettuce had antibacterial activity against Pseudomonas aeruginosa , with a minimum inhibitory concentration (MIC) of 0.156 and 0.625 μg/mL under S2/Se1 and S2/Se2 treatments, respectively. As with antibacterial activity, the acetone extract of green (V1) lettuce treated with adequate (S1) and higher S (S2) under Se-limiting conditions showed the ability to inhibit nitric oxide (NO) release from macrophages. NO production by macrophages was inhibited by 50% at respective concentrations of 106.1 ± 2.4 and 101.0 ± 0.6 μg/mL with no toxic effect on the cells, in response to S1 and S2, respectively, under Se-deficient conditions (Se0). Furthermore, the red cultivar (V2) exhibited the same effect as the green cultivar (V1) regarding NO inhibition, with IC 50 = 113.0 ± 4.2 μg/mL, in response to S1/Se2 treatments. Collectively, the promising NO inhibitory effect and antibacterial activity of red lettuce under the above-mentioned conditions might be attributed to the production of flavonoid glycosides and phenylpropanoic acid esters under the same condition. To the best of our knowledge, this is the first report to show the novel approach of the NO inhibitory effect of Se and S enrichment in food crops, as an indicator for the potential of Se and S as natural anti-inflammatory agents.

Background: Research on medicinal plants and extracts derived from them differs from studies performed with single compounds. Extracts obtained from plants, algae, fungi, lichens or animals pose some unique challenges: they are multicomponent mixtures of active, partially active and inactive substances, and the activity is often not exerted on a single target. Their composition varies depending on the method of preparation and the plant materials used. This complexity and variability impact the reproducibility and interpretation of pharmacological, toxicological and clinical research. Objectives: This project develops best practice guidelines to ensure reproducibility and accurate interpretations of studies using medicinal plant extracts. The focus is on herbal extracts used in pharmacological, toxicological, and clinical/intervention research. Specifically, the consensus-based statement focuses on defining requirements for: 1) Describing the plant material/herbal substances, herbal extracts and herbal medicinal products used in these studies, and 2) Conducting and reporting the phytochemical analysis of the plant extracts used in these studies in a reproducible and transparent way. The process and methods: We developed the guidelines through the following process: 1) The distinction between the three main types of extracts (extract types A, B, and C), initially conceptualised by the lead author (MH), led the development of the project as such; 2) A survey among researchers of medicinal plants to gather global perspectives, opportunities, and overarching challenges faced in characterising medicinal plant extracts under different laboratory infrastructures. The survey responses were central to developing the guidelines and were reviewed by the core group; 3) A core group of 9 experts met monthly to develop the guidelines through a Delphi process; and. 4) The final draft guidelines, endorsed by the core group, were also distributed for feedback and approval to an extended advisory group of 20 experts, including many journal editors. Outcome: The primary outcome is the "Consensus statement on the Phytochemical Characterisation of Medicinal Plant extracts" (ConPhyMP) which defines the best practice for reporting the starting plant materials and the chemical methods recommended for defining the chemical compositions of the plant extracts used in such studies. The checklist is intended to be an orientation for authors in medicinal plant research as well as peer reviewers and editors assessing such research for publication., Competing Interests: ZK is an employee of Dr. Willmar Schwabe GmbH & Co. KG, Germany, a company producing and distributing phytopharmaceuticals and his specific input into this project relates to the analytical techniques and their use in the industry focusing on technical and analytical aspects. BJ’s position was funded through the donation listed below. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Heinrich, Jalil, Abdel-Tawab, Echeverria, Kulić, McGaw, Pezzuto, Potterat and Wang.)

Cryopreservation and storage of semen for artificial insemination (AI) result in excessive accumulation of reactive oxygen species (ROS). This leads to a shortened life span and reduced motility of spermatozoa post-thawing, with consequent impairment of their function. However, certain levels of ROS are essential to facilitate the capacitation of spermatozoa required for successful fertilisation. Tannins, as well-known antioxidant compounds, may act as ROS binders/acceptors/scavengers to inhibit the damaging effects of ROS. This review comprises an analysis of the semen cryopreservation protocol and health functions of tannins, as well as the effects of ROS on fresh and cryopreserved semen's longevity and fertilisation. Additionally, we surveyed available evidence of the effects of tannin extract feed supplementation on male fertility. We furthermore interrogated existing theories on tannin use as a potential additive to semen extenders, its relationship with semen quality, and to what degree existing theories have been investigated to develop testable new hypotheses. Emphasis was placed on the effects of tannins on ROS, their involvement in regulating sperm structure and function during cryopreservation, and on post-thaw sperm motility, capacitation, and fertilising ability. The diverse effects of tannins on the reproductive system as a result of their potential metal ion chelation, protein precipitation, and biological antioxidant abilities have been identified. The current data are the first to support the further investigation of the incorporation of tannin-rich plant extracts into semen extenders to enhance the post-thaw survival, motility, and fertilising ability of cryopreserved spermatozoa.

Antimicrobial resistant poultry pathogens are responsible for treatment failure and economic losses, and can also be a source of resistant zoonotic infections representing a risk to human health. In 2006 the European Union banned the use of antibiotics as growth promoters in farm animals and other regions are likely to follow suit. Alternative products and strategies are sought to help maintain animal gut health to reduce the prevalence of pathogens in the food chain. The minimum inhibitory concentration (MIC) of organic and aqueous leaf extracts of Alchornea laxiflora, Ficus exasperata, Morinda lucida, Jatropha gossypiifolia, Ocimum gratissimum , and Acalypha wilkesiana were tested against bacterial poultry pathogens including Staphylococcus aureus, Enterococcus faecalis, Salmonella spp., Escherichia coli, Campylobacter spp., and fungal species ( Aspergillus fumigatus, Aspergillus flavus , and Candida albicans) using a 2-fold serial microdilution method. Activity of extracts against biofilms of the pathogens was done using a modified crystal violet staining in vitro assay. The safety of extracts was determined against Vero and Caco-2 cells using a tetrazolium-based in vitro assay. Acetone and cold water extracts of M . lucida had the best activity against three bacteria (MIC = 0.05-0.07 mg/ml) and two fungal (MIC = 0.03-0.15 mg/ml) organisms, respectively. The E . coli isolate and A . flavus were the most susceptible bacteria and fungi, respectively. Caco-2 cells generally displayed higher selectivity index (SI) values compared to Vero cells and average SI values against Vero and Caco-2 cells for both bacteria and fungi ranged from 0.01 to 4.48 and 0.005 to 16.41, respectively. All plant extracts had good anti-biofilm activity (>50%) against at least one organism. The disruption of established biofilm growth by the plant samples proved to be more difficult to achieve than efficacy against planktonic forms of bacteria. This study shows that some of the plant species are potential candidates as alternative feed additives in poultry production. In the future, a poultry feed trial to evaluate their in vivo efficacy as herbal feed additives will be conducted., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Olawuwo, Famuyide and McGaw.)

Plant remedies used in avian ethnomedicine are potential candidates for the development of phytogenic feed additives. An ethnoveterinary survey was carried out in 3 districts in Zimbabwe to document plants used in poultry ethnomedicine and identify plants that have the potential to be used for the development of poultry phytogenic feed additives. The survey employed questionnaire-guided oral interviews with 146 smallholder farmers. Key areas of investigation and discussion were poultry production and traditional knowledge in bird health care (ethnotreatments and poultry disease control). The survey documented a total of 36 plant species cited as being useful interventions for the treatment and management of various poultry ailments/health constraints. These medicinal plants belonged to 22 families, with the Fabaceae family the dominant family. The plant species were used to treat 11 disease/health constraint categories, with the highest number of species being used for coccidiosis. Trees (44.44%) were the main reservoir of medicinal plants followed by herbs (36.11%), shrubs (8.33%), climbers (8.33%), and flowers (2.78%). Based on the results of the survey, Bobgunnia madagascariensis, Aloe chabaudii, Adenia gummifera, Erythrina abyssinica, Agave sisalana, Capsicum frutescens, Strychnos cocculoides, Aloe greatheadii, Tridactyle bicaudata, Senna singueana, Sarcostemma viminale, Morus alba, and Moringa oleifera are potential candidates for the development of phytogenic feed additives., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

There has been burgeoning interest in plant-based feed additives following restrictions placed on the use of antibiotic feed additives in many countries. Phytogenic feed additives are recommended to have a range of useful properties to support the growth and development of poultry to a similar level as that obtained by supplementing feed with antibiotics. The aim of this study was to evaluate the antibacterial, anti-lipoxygenase and antioxidant activity, and in vitro safety of fractions and isolated compounds from leaves of Senna singueana . Antibacterial activities of the fractions and isolated compounds were determined against a panel of bacteria using a two-fold serial microdilution assay and qualitative bioautography assays. Anti-lipoxygenase activity was evaluated using the ferrous oxidation-xylenol orange (FOX) method. Antioxidant activity was assessed qualitatively and quantitatively using radical scavenging assays. Dichloromethane and ethyl acetate fractions from solvent-solvent partitioning had the best antibacterial activity with MIC values ranging from 156 to 313 μg/ml. Fractions obtained from column chromatography had significant to weak antibacterial activity with MIC values ranging from 50 to 1,250 μg/ml. Bioautography showed clear bands of bacterial inhibition, indicating the presence of a number of active compounds in several fractions. The ethyl acetate fraction and all the tested column fractions had potent anti-lipoxygenase activity with IC 50 values of ≤2.5 μg/ml which were lower than that of quercetin (positive control), indicating anti-inflammatory potential. The ethyl acetate fraction and several column fractions had powerful antioxidant activity with IC 50 values of ≤5 μg/ml in the ABTS assay. Cytotoxicity values against Vero kidney cells ranged from LC 50 = 40.0-989.3 μg/ml. Bioassay-guided fractionation led to the isolation and identification of a known bioactive compound, luteolin. S. singueana is a promising candidate for the development of poultry phytogenic feed additives., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jambwa, Makhubu, Matope, Fouche and McGaw.)

Tuberculosis (TB) is a disease of global importance that affects millions of people. Approximately a quarter of the world's population is currently infected with M. tuberculosis , and about 10% of those infected will develop into active disease, particularly immune compromised individuals. Helminthiasis is of global health importance, affecting over 2 billion people mostly in resource-poor countries. Co-infection with tuberculosis (TB) and helminths (worms) is an emerging global public health concern with both affecting about one-third of the global population. Chronic infection with helminths can result in impaired immune responses to TB as well as enhancing failure to TB therapy and BCG vaccination. Antimycobacterial and anthelmintic activities of the acetone extract and fractions of Psychotria capensis were evaluated, including their in vitro safety. In addition, the anti-inflammatory and immunomodulatory effect of the fractions and crude extract of P. capensis were assessed. Antimycobacterial activity of the extract and fractions was tested against four non-tuberculous mycobacteria ( Mycobacterium smegmatis , M. fortuitum , M. aurum, M. bovis BCG) and pathogenic M. tuberculosis H37Rv while the Egg Hatch Assay (EHA) was used for the anthelmintic test on eggs of Haemonchus contortus . Cytotoxicity was determined against Vero kidney cells while in vitro immune modulation via cytokine production was determined on activated macrophages. The minimum inhibitory concentration (MIC) values of the Psychotria capensis acetone extract and fractions ranged from 39 to 1,250 μg/ml with the crude extract and hexane fraction having the best MIC values (both 39 μg/ml). In the EHA, the inhibitory concentration (IC 50 ) ranged from 160 to 630 μg/ml with the hexane fraction having the best activity. The hexane and chloroform fractions were relatively non-toxic with LC 50 values of 290 and 248 μg/ml respectively, while the acetone crude extract (64 μg/ml) and n-butanol fraction (71 μg/ml) were moderately toxic. The SI values (LC 50 /MIC) ranged from 0.1 to 7.4 with the hexane fraction having the highest value against M. smegmatis (7.4). The hexane fraction had the best dual anthelmintic and antimycobacterial activity. This fraction had the best NO inhibitory activity and was the least cytotoxic, indicating that its activity was not due to general metabolic toxicity, with 96.54% cell viability. Pro-inflammatory cytokines such as IL-12p70 were upregulated while IL-10 expression was inhibited by the extracts. Compounds were detected using GC-MS analysis, and in both the crude acetone extract and the hexane fraction was the diterpene neophytadiene, which has anti-inflammatory and antimicrobial activity. Finding alternative or complementary approaches to dealing with TB infections by, amongst other things, reducing the incidence of helminth infestations may lessen the burden of TB, contributing to slowing the spread of multi-drug resistance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Aro, Famuyide, Oyagbemi, Kabongo-Kayoka and McGaw.)

Exposure to dibutyl phthalate (DBP) induces testicular damage in mammals. However, studies on the effects of DBP on spermatogenic cells in birds are grossly lacking. Therefore, this study was designed to determine the effects of the pre-pubertal exposure to DBP on the histology and ultrastructure of spermatogenic cells in the testis of adult Japanese quail (Coturnix coturnix japonica). The birds were randomly divided into five dosage groups at the age of 4 weeks. The control group received a corn oil vehicle only (a dose of 1 mL/kg body weight), while the other four experimental groups received a daily dosage of 10, 50, 200, 400 mg/kg body weight of DBP (dissolved in corn oil), respectively with the aid of gastric lavage, for 30 days. Testicular samples were processed and examined by light microscopy and transmission electron microscopy. Histopathological evaluation revealed vacuole formation, germ cell degenerations, and the absence of spermatogenic cell series. Ultrastructurally, chromatin clumps in spermatocyte and degenerated spermatogonia with ruptured nuclear membranes resting on the distorted basement membranes were observed. Others were intracytoplasmic vacuoles in round spermatids and fragments of dense apoptotic bodies. In conclusion, the findings of the present study reveal that spermatogenic cells of Japanese quails seem to be more sensitive to DBP-induced degeneration compared to mammalian species studied. The Japanese quail could be used to monitor environmental contamination with low doses of DBP., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study aimed to determine in vitro anthelmintic activity of plant extracts of eleven plant species used traditionally in South Africa to treat various disorders including symptoms related to nematode infections, and to isolate bioactive compounds from the most active plant extract. Crude plant extracts were tested on different life-cycle stages of Haemonchus contortus. The cytotoxicity of the most active extracts, fractions and compounds was evaluated on Vero cells and the most potent extract, fractions and compounds were tested for their ability to kill the parasitic H. contortus and the free-living nematode Caenorhabditis elegans. Typha capensis acetone extract had the strongest egg hatching inhibitory effect with an EC 50 of 184.94 μg/mL, and this extract also halted larval development of H. contortus with an EC 50 of 83.30 μg/mL compared to the positive control (albendazole) with an EC 50 of 2.66 μg/mL. Typha capensis crude extract and its butanol fraction had promising anthelmintic activity against both parasitic H. contortus and free-living C. elegans. Two compounds isolated from T. capensis, namely, isorhamnetin-3-O-β-D-glucoside and isorhamnetin 3-O-rutinoside, had antioxidant activity with IC 50 values of 3.16 μg/mL and 0.96 μg/mL respectively, and good anthelmintic activity against H. contortus with IC 50 values of 55.61 μg/mL and 145.17 μg/mL respectively. Identification of bioactive compounds from the T. capensis crude extract supports development of this extract as a complementary or alternative treatment against haemonchosis. However, further research is necessary to confirm the anthelmintic efficacy of the plant, including in vivo studies., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: This study evaluated the in vitro antioxidant activity and comparison of anti-inflammatory and cytotoxic activity of Harpagopytum zeyheri with diclofenac., Methods: In vitro assays were conducted using water, ethanol, and ethyl acetate extracts of H.zeyheri. The antioxidant activity was evaluated using the 2,2'-diphenyl-1-picrylhydrazy (DPPH) and 2,2'- azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. The anti-inflammatory activity was determined by measuring the inhibition of nitric oxide (NO) on lipopolysaccharide (LPS)-induced RAW 264.7 mouse macrophages as well as cytokine (TNF-α and IL-10) expression on LPS-induced U937 human macrophages. For cytotoxicity, cell viability was determined using the 3-(4, 5-dimethylthiazol- 2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay., Results: The ethyl acetate extract had the lowest IC 50 values in the DPPH (5.91 μg/ml) and ABTS (20.5 μg/ml) assay compared to other extracts. Furthermore, the ethyl acetate extracts effectively inhibited NO and TNF-α and proved to be comparable to diclofenac at some concentrations. All extracts of H. zeyheri displayed dose-dependent activity and were associated with low levels of human-IL-10 expression compared to quercetin. Furthermore, all extracts displayed low toxicity relative to diclofenac., Conclusions: These findings show that H. zeyheri has significant antioxidant activity. Additionally, similarities exist in the inflammatory activity of H. zeyheri to diclofenac at some concentrations as well as low toxicity in comparison to diclofenac., (© 2021. The Author(s).)

No abstract available.

Ethnopharmacological Relevance: Combretum species are used traditionally for the treatment of diarrhoea, hookworm, fever, inflammation, pain and infectious diseases. Infections are commonly caused by the intake of food contaminated with foodborne pathogens. These are a significant concern in the food industry owing to their ability to form biofilms and cause food spoilage, despite the availability of modern food preservation techniques. Combretum elaeagnoides Klotzsch (Combretaceae) is used in southern African traditional medicine against infections and diarrhoea., Aim of the Study: This study evaluated the antimicrobial ability of C. elaeagnoides leaf fractions and the isolated compound quercetin-3-O-rhamnoside against a panel of foodborne pathogens, and biofilms formed by them. The samples were also assessed for their antioxidant activity and cytotoxicity., Materials and Methods: Fractions prepared from the methanol extract of the leaves, and a bioactive compound (quercetin-3-O-rhamnoside) isolated from the ethyl acetate fraction were investigated for activity against nine reference and clinical strains of foodborne pathogens. The microdilution method was used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the fractions and compound. The inhibition of biofilm formation and the crystal violet staining assays were used to determine the antibiofilm efficacy. The DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay and the 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) electron reduction assay were used to determine the antioxidant potential of the fractions and compound. The cytotoxicity was assessed using the 3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay against Vero African monkey kidney cells., Results: The fractions were active against all tested organisms, with MIC values ranging from 0.03 to 1.25 mg/mL. The best MBC was 0.63 mg/mL. All the fractions and the purified compound inhibited biofilm formation of Staphylococcus aureus and Salmonella Typhimurium, with percentage inhibition values greater than 50% at 1 mg/mL. The compound had very promising antibiofilm activity against Escherichia coli 1 (ATCC 25922) with percentage inhibition of >150%. The compound and fractions had good radical scavenging potential against the DPPH and ABTS radicals. Quercetin-3-O-rhamnoside and the fractions were relatively non-cytotoxic., Conclusion: The ability of the fractions and compound to reduce and inhibit biofilm biomass and their promising antioxidant potential provide motivation to further investigate the use of plants to protect food products from contamination, as well as to treat infections characterized by bacterial biofilms., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Plants of the genus Euphorbia are widely distributed across temperate, tropical and subtropical regions of South America, Asia and Africa with established Ayurvedic, Chinese and Malay ethnomedical records. The present review reports the isolation, occurrence, phytochemistry, biological properties, therapeutic potential and structure-activity relationship of Euphorbia flavonoids for the period covering 2000-2020, while identifying potential areas for future studies aimed at development of new therapeutic agents from these plants. The findings suggest that the extracts and isolated flavonoids possess anticancer, antiproliferative, antimalarial, antibacterial, anti-venom, anti-inflammatory, anti-hepatitis and antioxidant properties and have different mechanisms of action against cancer cells. Of the investigated species, over 80 different types of flavonoids have been isolated to date. Most of the isolated flavonoids were flavonols and comprised simple O -substitution patterns, C-methylation and prenylation. Others had a glycoside, glycosidic linkages and a carbohydrate attached at either C-3 or C-7, and were designated as d-glucose, l-rhamnose or glucorhamnose. The structure-activity relationship studies showed that methylation of the hydroxyl groups on C-3 or C-7 reduces the activities while glycosylation loses the activity and that the parent skeletal structure is essential in retaining the activity. These constituents can therefore offer potential alternative scaffolds towards development of new Euphorbia -based therapeutic agents.

Background: Owing to antibiotic resistance, alternative antimicrobials from medicinal plants are receiving attention as leads for anti-infective agents. This study aimed to investigate selected tree species and their constituents for activity against bacterial foodborne pathogens, particularly Salmonella serovars., Methods: Antibacterial activity of ten plant species was determined by serial microdilution against bacteria implicated in causing gastrointestinal ailments. Active compounds were isolated from Loxostylis alata using bioassay-guided fractionation. Antioxidant activity was determined using free-radical scavenging assays. Cytotoxicity and genotoxicity of the extracts was ascertained on Vero cells, and using the Ames assay respectively., Results: Extracts had low to moderate MIC values from 0.04 to 2.5 mg/mL. Protorhus longifolia and Loxostylis alata were most active and L. alata had the highest selectivity index value (2.51) against Salmonella Typhimurium, as well as high antioxidant activity. Cytotoxicity values ranged from 0.02 to 0.47 mg/mL, while tested extracts were not genotoxic. Bioactive compounds isolated from L. alata included delicaflavone and a polymethoxyflavone., Conclusions: The Loxostylis alata leaf extract had strong activity against Salmonella serovars but isolated compounds were less active, indicating likely synergistic effects. Extracts of L. alata are promising candidates for development of antimicrobial preparations or food additives against microbial contamination.

Background: Some viruses play a key role in the disturbance of the digestive system. The common viruses which cause infectious diarrhoea (gastroenteritis) include astrovirus, caliciviruses, coronavirus and torovirus which are single-stranded RNA viruses. Influenza A virus (H1N1) also causes diarrhoea in addition to being associated with respiratory symptoms. In preliminary studies, Newtonia hildebrandtii and N. buchananii leaf extracts had good antibacterial activity against some bacteria implicated in causing diarrhoea. The aim of this study was to evaluate the anti-influenza activity of two Newtonia species extracts and the isolated compound (myricitrin)., Methods: N. hildebrandtii and N. buchananii acetone, and MeOH: DCM (methanol-dichloromethane) leaf and stem extracts, and an antibacterial compound myricetin-3-o-rhamnoside (myricitrin), isolated from N. buchananii, were evaluated for their antiviral efficacy against influenza A virus (IAV) PR8/34/H1N1 as a model organism. The MTT and hemagglutination assays were used to assess the extracts and compound interference with cell viability and viral surface HA glycoprotein. The quantitative real-time PCR was performed to assess the viral load., Results: Plant extracts of N. hildebrandtii and N. buchananii were effective against IAV. The extracts in combination with H1N1 showed highly significant antiviral activity (P < 0.01) and maintained cell viabilities (P < 0.05). Myricitrin was non-cytotoxic at concentration 104 μg/ml. Myricitrin was most effective against IAV in a co-penetration combined treatment, thereby confirming the inhibitory effect of this compound in the viral attachment and entry stages. Myricitrin treatment also resulted in the highest viability of the cells in co-penetration treatment. The activity of myricitrin indicates the potential of the extracts in controlling viral infection at the attachment stage. The antiviral effect of myricitrin on IAV load in MDCK cell culture was confirmed using quantitative real-time PCR., Conclusion: Data from this study support further research and development on Newtonia hildebrandtii, Newtonia buchananii and myricitrin to address diarrhoea and related conditions caused by viruses in both human and veterinary medicine. Further work needs to be conducted on the activity of the extracts and the purified compound on other viruses of importance which have similar symptoms to influenza virus such as the coronavirus which led to a recent global pandemic.

The emergence of viral pneumonia caused by a novel coronavirus (CoV), known as the 2019 novel coronavirus (2019-nCoV), resulted in a contagious acute respiratory infectious disease in December 2019 in Wuhan, Hubei Province, China. Its alarmingly quick transmission to many countries across the world and a considerable percentage of morbidity and mortality made the World Health Organization recognize it as a pandemic on March 11, 2020. The perceived risk of infection has led many research groups to study COVID-19 from different aspects. In this literature review, the phylogenetics and taxonomy of COVID-19 coronavirus, epidemiology, and respiratory viruses similar to COVID-19 and their mode of action are documented in an approach to understand the behavior of the current virus. Moreover, we suggest targeting the receptors of SARS-CoV and SARS-CoV-2 such as ACE2 and other proteins including 3CLpro and PLpro for improving antiviral activity and immune response against COVID-19 disease. Additionally, since phytochemicals play an essential role in complementary therapies for viral infections, we summarized different bioactive natural products against the mentioned respiratory viruses with a focus on influenza A, SARS-CoV, MERS, and COVID-19.Based on current literature, 130 compounds have antiviral potential, and of these, 94 metabolites demonstrated bioactivity against coronaviruses. Interestingly, these are classified in different groups of natural products, including alkaloids, flavonoids, terpenoids, and others. Most of these compounds comprise flavonoid skeletons. Based on our survey, xanthoangelol E ( 88 ), isolated from Angelica keiskei (Miq.) Koidz showed inhibitory activity against SARS-CoV PLpro with the best IC 50 value of 1.2 μM. Additionally, hispidulin ( 3 ), quercetin ( 6 ), rutin ( 8 ), saikosaponin D ( 36 ), glycyrrhizin ( 47 ), and hesperetin ( 55 ) had remarkable antiviral potential against different viral infections. Among these compounds, quercetin ( 6 ) exhibited antiviral activities against influenza A, SARS-CoV, and COVID-19 and this seems to be a highly promising compound. In addition, our report discusses the obstacles and future perspectives to highlight the importance of developing screening programs to investigate potential natural medicines against COVID-19., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Omrani, Keshavarz, Nejad Ebrahimi, Mehrabi, McGaw, Ali Abdalla and Mehrbod.)

It has been established that excess germ cells in normal and in pathological conditions are removed from testicular tissue by the mechanism of apoptosis. Studies on germ cell apoptosis in avian species are grossly lacking, and there are only a few reports on induced germ cell degenerations in the testis tissue of birds. This study was designed to investigate the process of apoptosis of germ cells in the Japanese quail (Coturnix coturnix japonica). Germ cell degenerations were investigated in birds of all age groups, namely pre-pubertal, pubertal, adult, and aged. Apoptosis of germ cells in the quails, as shown by hematoxylin & eosin (H&E), TdT dUTP Nick End Labeling (TUNEL) assay and electron microscopy, was similar to that observed in previous studies of germ cells and somatic cells of mammalian species. The observed morphological features of these apoptotic cells ranged from irregular plasma and nuclear membranes in the early stage of apoptosis to rupture of the nuclear membrane, condensation of nuclear material, as well as fragments of apoptotic bodies, in later stages of apoptosis. In the TUNEL-positive cell counts, there was a significant difference between the mean cell counts for the four age groups (P < 0.05). Post hoc analysis revealed a highly significant difference in the aged group relative to the pubertal and adult age groups, while the cell counts of the pre-pubertal group were significantly higher than those of the pubertal group. However, there was no significant difference between cell counts of the pre-pubertal and the adult, and between the pre-pubertal and the aged groups., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Diarrhoea is a major health issue in both humans and animals and may be caused by bacterial, viral and fungal infections. Previous studies highlighted excellent activity of Newtonia buchananii and N. hildebrandtii leaf extracts against bacterial and fungal organisms related to diarrhoea-causing pathogens. The aim of this study was to isolate the compound(s) responsible for antimicrobial activity and to investigate efficacy of the extracts and purified compound against bacterial biofilms., Methods: The acetone extract of N. buchananii leaf powder was separated by solvent-solvent partitioning into eight fractions, followed by bioassay-guided fractionation for isolation of antimicrobial compounds. Antibacterial activity testing was performed using a broth microdilution assay. The cytotoxicity was evaluated against Vero cells using a colorimetric MTT assay. A crystal violet method was employed to test the inhibitory effect of acetone, methanol: dichloromethane and water (cold and hot) extracts of N. buchananii and N. hildebrandtii leaves and the purified compound on biofilm formation of Pseudomonas aeruginosa, Escherichia coli, Salmonella Typhimurium, Enterococcus faecalis, Staphylococcus aureus and Bacillus cereus., Results: Myricetin-3-o-rhamnoside (myricitrin) was isolated for the first time from N. buchananii. Myricitrin was active against B. cereus, E. coli and S. aureus (MIC = 62.5 μg/ml in all cases). Additionally, myricitrin had relatively low cytotoxicity with IC 50  = 104 μg/ml. Extracts of both plant species had stronger biofilm inhibitory activity against Gram-positive than Gram-negative bacteria. The most sensitive bacterial strains were E. faecalis and S. aureus. The cold and hot water leaf extracts of N. buchananii had antibacterial activity and were relatively non-cytotoxic with selectivity index values of 1.98-11.44., Conclusions: The purified compound, myricitrin, contributed to the activity of N. buchananii but it is likely that synergistic effects play a role in the antibacterial and antibiofilm efficacy of the plant extract. The cold and hot water leaf extracts of N. buchananii may be developed as potential antibacterial and antibiofilm agents in the natural treatment of gastrointestinal disorders including diarrhoea in both human and veterinary medicine.

Background: Antibiotics are commonly added to livestock feeds in sub-therapeutic doses as growth promoters and for prophylaxis against pathogenic microbes, especially those implicated in diarrhoea. While this practice has improved livestock production, it is a major cause of antimicrobial resistance in microbes affecting livestock and humans. This has led to the banning of prophylactic antibiotic use in animals in many countries. To compensate for this, alternatives have been sought from natural sources such as plants. While many studies have reported the antimicrobial activity of medicinal plants with potential for use as phytogenic/botanical feed additives, little information exists on their mode of action. This study is based on our earlier work and describes ultrastructural damage induced by acetone crude leaf extracts of Syzygium legatii and Eugenia zeyheri (Myrtaceae) active against diarrhoeagenic E. coli of swine origin using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and fluorescent microscopy (FM). Gas chromatography/mass spectrometry (GC-MS) was used to investigate the chemical composition of plant extracts., Results: The extracts damaged the internal and external anatomy of the cytoplasmic membrane and inner structure at a concentration of 0.04 mg/mL. Extracts also led to an increased influx of propidium iodide into treated bacterial cells suggesting compromised cellular integrity and cellular damage. Non-polar compounds such as α-amyrin, friedelan-3-one, lupeol, and β-sitosterol were abundant in the extracts., Conclusions: The extracts of S. legatii and E. zeyheri caused ultrastructural damage to E. coli cells characterized by altered external and internal morphology. These observations may assist in elucidating the mode of action of the extracts.

This study reports the first total synthesis of the bioactive oxepinochromones 12- O -acetyleranthin ( 8 ) (angular isomer) and 12- O -acetylptaeroxylinol ( 9 ) (linear isomer). The antifungal activity of these compounds and their derivatives was determined against Candida albicans and Cryptococcus neoformans . Most compounds had good selectivity between the two fungi and showed moderate to good activity. 12- O -Acetyleranthin ( 8 ) had the highest activity against C. albicans , with an MIC value of 9.9 μM, while 12- O -acetylptaeroxylinol ( 9 ), the compound present in Ptaeroxylon obliquum , had the highest activity against C. neoformans , with an MIC value of 4.9 μM.

Background: Urinary tract infections (UTIs) caused by opportunistic pathogens are among the leading health challenges globally. Most available treatment options are failing as a result of antibiotic resistance and adverse effects. Natural sources such as plants may serve as promising alternatives., Methods: Compounds were isolated from the South African weed Chromolaena odorata through column chromatography. Purified compounds were tested for antimicrobial activity using the p-iodonitrotetrazolium chloride (INT) colorimetric method, against uropathogenic Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Aspergillus fumigatus and Cryptococcus neoformans. Anti-biofilm, anti-adhesion and metabolic inhibition activities were investigated against selected strains. Safety of the compounds was determined against Vero monkey kidney, C3A human liver and colon (Caco2) cells., Results: Four compounds identified as pectolinaringenin (1), (±)-4',5,7-trimethoxy flavanone (2), 5-hydroxy-3,7,4'-trimethoxyflavone (3) and 3,5,7-trihydroxy-4'-methoxyflavone) (4) were isolated. Minimum inhibitory concentration (MIC) varied between 0.016 and 0.25 mg/mL. Compounds 2 and 3 showed promising antimicrobial activity against E. coli, S. aureus, K. pneumoniae, A. fumigatus and C. neoformans with MIC between 0.016 and 0.125 mg/mL, comparable to gentamicin, ciprofloxacin and amphotericin B used as positive controls. Compounds 2 and 3 showed good anti-biofilm and metabolic inhibition activities against E. coli and S. aureus but weak anti-adhesion activity against the organisms. Low toxicity with selectivity indexes between 1 and 12.625 were recorded with the compounds, indicating that the compounds were rather toxic to the microbial strains and not to the human and animal cells., Conclusion: Pharmacological activities displayed by compounds 2 and 3 isolated from C. odorata and low toxicity recorded credits it as a potential lead for the development of useful prophylactic treatments and anti-infective drugs against UTIs. Although known compounds, this is the first time these compounds have been isolated from the South African weed C. odorata and tested for antimicrobial, anti-biofilm, metabolic inhibition and anti-adhesion activities.

Ethnopharmacological Relevance: Ethnoveterinary medicine (EVM) practices remain a common feature of South African animal husbandry, particularly in rural livestock healthcare. This review provides an update of research undertaken on South African EVM from 2009 until 2019., Aim of the Study: This review collates information and investigates trends in the increasing field of EVM research in South Africa over the last decade., Materials and Methods: A literature search was conducted using available databases including ScienceDirect, PubMed, Scopus and Google Scholar. Dissertations, theses, books and technical reports were also searched., Results: In the past decade, ethnoveterinary surveys conducted in South Africa report the use of 139 plants from 50 families used against 21 animal diseases and conditions. Leaves, roots and bark have remained popular plant parts used for EVM. In terms of livestock species reported, the major focus was on cattle, goats and poultry. Only four of the nine provinces in the country have been surveyed., Conclusions: Relatively few publications reporting on ethnoveterinary surveys have originated from South Africa. These papers refer to many plants used for a variety of commonly encountered animal diseases and afflictions. With reference to recently published guidelines on conducting ethnobotanical surveys, several recommendations can be made to improve the robustness of surveys documenting the use of plants for EVM in South Africa., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Kigelia africana is used to manage inflammation among indigenous communities. We hypothesized that K. africana extracts contain phytoconstituents with good antioxidant and anti-inflammatory activities. The methanolic extract of K. africana fruits and Spathodea campanulata leaves (SPK04), K. africana aqueous fruit extract (KFM02), and K. africana acetone fruit extract (KFM05) were subjected to antioxidant and anti-inflammatory assays. Antioxidant activity was evaluated using the ABTS radical scavenging assay, and the MTT cell viability assay was used for cytotoxicity. The extracts were preincubated with enzymes and assayed for 15-LOX and COX-2 enzyme activity using an ELISA method. Nitric oxide (NO) inhibitory effect of the extracts was evaluated and measurement of proinflammatory cytokines (IL-1 β , TNF- α , and IL-6) and the anti-inflammatory cytokine (IL-10) was done using ELISA kits. SPK04 had the highest antioxidant activity with a mean inhibition of 99.37 ± 0.56% and an IC 50 of 4.28  µ g/mL. SPK04 and KFM05 did not inhibit 15-LOX as their IC 50 values were >1000  μ g/mL. All extracts were safe on Vero cells at the highest concentration (200  µ g/mL) tested. KFM02 was the best inhibitor of NO production and had the highest cell viability at both the lowest (50  µ g/mL) and highest concentrations (200  µ g/mL). SPK04 was the best COX-2 inhibitor while KFM05 expressed the strongest suppression effect for IL- β and IL-6. KFM02 did not inhibit IL-6 at the highest concentration (200  µ g/mL). The order of suppression of TNF- α by the extracts differed across concentrations, KFM05 > SPK04 > KFM02 at 200  µ g/mL, KFM02 > SPK04 > KFM05 at 100  µ g/mL, and SPK04 > KFM02 > KFM05 at 50  µ g/mL. All the tested extracts had no inhibitory effect against IL-10. SPK04, KFM05, and KFM02 had good antioxidant and anti-inflammatory activity and this supports their use as potential anti-inflammatory therapies. This study presents for the first time the antioxidant and anti-inflammatory activity of K. africana and S. campanulata polyherbal extract. It is also among the very few studies that have reported the inhibitory effect of cytokines IL-1 β , TNF- α , IL-6, and IL-10 by K. africana ., Competing Interests: The authors report no conflicts of interest in this work., (Copyright © 2020 Alice Nabatanzi et al.)

This study aimed to evaluate the selective cytotoxicity of six natural compounds on four cancerous cells (MCF-7, HeLa, Caco-2 and A549) and two normal intestinal and lung cells (Hs1.Int and Wl-38) cells. We also attempted to analyze basically the structure-activity relationships and to understand the mechanism of action of active compounds using the Caspase-Glo® 3/7 kit. Globimetulin B (2) isolated from Globimetula dinklagei was significantly cytotoxic on cancerous cells with 50% inhibitory concentrations (IC50) ranging from 12.75 to 37.65 μM and the selectivity index (SI) values varying between 1.13 and 3.48 against both normal cells. The compound 3-O-β-d-glucopyranosyl-28-hydroxy-α-amyrin (5) isolated from Phragmanthera capitata exhibited the highest cytotoxic activity on HeLa cells with the IC50 of 6.88 μM and the SI of 5.20 and 8.71 against Hs1.Int and Wl-38 cells, respectively. A hydroxyl group at C-3 of compounds was suggested as playing an important role in the cytotoxic activity. The induction of caspase-3 and -7 activity represents some proof that apoptosis has occurred in treated cells. Globimetulin B (2) selectively killed cancer cells with less toxicity to non-cancerous cells as compared to conventional doxorubicin therapy.

Fluoride is an environmental contaminant that is ubiquitously present in air, water, and soil. It is commonly added in minute quantity to drinking water, toothpaste, and mouth rinses to prevent tooth decay. Epidemiological findings have demonstrated that exposure to fluoride induced neurodevelopmental toxicity, developmental neurotoxicity, and motor disorders. The neuroprotective effect of clofibrate, a peroxisome proliferator-activated receptor alpha agonist, was investigated in the present study. Forty male Wistar rats were used for this study and randomly grouped into 10 rats per group as control, sodium fluoride (NaF) alone (300 ppm), NaF plus clofibrate (250 mg/kg), and NaF plus lisinopril (10 mg/kg), respectively, for 7 days. NaF was administered in drinking water while clofibrate and lisinopril were administered by oral gavage. Markers of neuronal inflammation and oxidative stress, acetylcholinesterase activity, and neurobehavioral (hanging wire and open field) tests were performed. Immunohistochemistry was performed on brain tissues, and they were probed with glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, and cerebellar Ca 2+ -binding protein calbindin-D28k. The results showed that NaF significantly increased of oxidative stress and neuroinflammation and inhibited AChE activity. Immunostaining showed reactive astrocytes, microgliosis, loss of dendritic spines, and arborization in Purkinje cells in rats administered only NaF. Neurobehavioral results showed that cotreatment of NaF with clofibrate improved muscular strength and locomotion, reduced anxiety, and significantly reduced astrocytic count. Overall, cotreatment of NaF with either clofibrate or lisinopril showed neuroprotective effects by mitigating neuronal inflammation and oxidative and motor incoordination. Hence, clofibrate could be seen as a novel drug candidate against neurodegeneration and motor disorders., (© 2019 Wiley Periodicals, Inc.)

Background: Influenza A virus (IAV) is still a major health threat. The clinical manifestations of this infection are related to immune dysregulation, which causes morbidity and mortality. The usage of traditional medication with immunomodulatory properties against influenza infection has been increased recently. Our previous study showed antiviral activity of quercetin-3-O-α-L-rhamnopyranoside (Q3R) isolated from Rapanea melanophloeos (RM) (L.) Mez (family Myrsinaceae) against H1N1 (A/PR/8/34) infection. This study aimed to confirm the wider range of immunomodulatory effect of Q3R on selective pro- and anti-inflammatory cytokines against IAV in vitro, to evaluate the effect of Q3R on apoptosis pathway in combination with H1N1, also to assess the physical interaction of Q3R with virus glycoproteins and RhoA protein using computational docking., Methods: MDCK cells were exposed to Q3R and 100CCID 50 /100 μl of H1N1 in combined treatments (co-, pre- and post-penetration treatments). The treatments were tested for the cytokines evaluation at RNA and protein levels by qPCR and ELISA, respectively. In another set of treatment, apoptosis was examined by detecting RhoA GTPase protein and caspase-3 activity. Molecular docking was used as a tool for evaluation of the potential anti-influenza activity of Q3R., Results: The expressions of cytokines in both genome and protein levels were significantly affected by Q3R treatment. It was shown that Q3R was much more effective against influenza when it was applied in co-penetration treatment. Q3R in combination with H1N1 increased caspase-3 activity while decreasing RhoA activation. The molecular docking results showed strong binding ability of Q3R with M2 transmembrane, Neuraminidase of 2009 pandemic H1N1, N1 and H1 of PR/8/1934 and Human RhoA proteins, with docking energy of - 10.81, - 10.47, - 9.52, - 9.24 and - 8.78 Kcal/mol, respectively., Conclusions: Quercetin-3-O-α-L-rhamnopyranoside from RM was significantly effective against influenza infection by immunomodulatory properties, affecting the apoptosis pathway and binding ability to viral receptors M2 transmembrane and Neuraminidase of 2009 pandemic H1N1 and human RhoA cellular protein. Further research will focus on detecting the detailed specific mechanism of Q3R in virus-host interactions.

Background: Many studies have revealed that bioactive compounds for different indications are not extracted from plants with water, the only extractant practically available to rural communities. We compared the acaricidal activity of acetone extracts of 13 species used traditionally to protect cattle against ticks. We also investigated if the extraction of biologically active compounds against Rhipicephalus (Boophilus) decoloratus ticks could be enhanced by adding a liquid soap that is locally available to smallholder farmers., Methods: A total of 13 plant species selected based on reported traditional use in Zimbabwe, were dried and finely ground before extraction with water, or water plus a surfactant, or acetone. The adapted Shaw Larval Immersion Test (SLIT) method was used to determine the activity of acetone and crude water extracts with or without liquid soap against the tick larvae. The activity of four fractions of crude acetone extracts (extracted using solvents of different polarity), of the most active plant species, Maerua edulis (tuber and leaf) was also compared to identify the most active fraction., Results: Aqueous plant extracts were not toxic to ticks, but the addition of 1% liquid soap as a surfactant increased mortality of the R. (B) decoloratus larvae significantly. With the Maerua edulis tuber extract, the efficacy of the 1% liquid soap was comparable to that of the amitraz based commercial synthetic acaricide. The use of acetone as an extractant, also increased the mortality of the tick larvae in all the plant species. With M. edulis (tuber and leaf), Monadenium lugardae and Kleinia sp. acetone extracts, the activity was comparable to that of the positive control (a commercially available amitraz-based synthetic acaricide). The non-polar fractions of the acetone extract of leaf and tuber of M. edulis caused up to 100% mortality. This indicates that non-polar to intermediate polarity compounds are responsible for the acaricidal activity., Conclusion: Organic solvents such as acetone extracted active compounds but water did not. By adding commonly available dishwashing soap to water active compounds were extracted leading to a high acaricidal activity of the plant extracts. In some cases, it was as active as non-polar extracts and a synthetic commercial acaricide (positive control). This approach makes it possible for the smallholder farmers and traditional healers to extract biologically active compounds from plants by using water.

Ethnopharmacological Relevance: Hypoxis hemerocallidea (commonly known as African Potato) is popular in African traditional medicine. It is used in the management of diverse ailments including burns, wounds and skin-related diseases., Aim of the Study: The current study investigated the antimicrobial effects of Hypoxis hemerocallidea against six microorganisms associated with skin diseases. In addition, the antioxidant activity, phytochemical profiles and cytotoxicity of the bulb extracts were evaluated., Materials and Methods: The antimicrobial activity of 50% methanol (MeOH) and petroleum ether (PE) extracts of Hypoxis hemerocallidea bulbs was tested against two bacterial and four fungal strains implicated in causing opportunistic skin-related diseases. Antioxidant potential of the extract was investigated via the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging assay and β-carotene linoleic acid model. Phytochemical profiling of the 50% MeOH extract of Hypoxis hemerocallidea was done using spectrophotometric assay and Gas Chromatography-Mass Spectrometry (GC-MS). The extracts were also evaluated for cytotoxicity against African green monkey Vero kidney cell lines based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay., Results: Both 50% MeOH and PE extracts showed considerable inhibitory effects against all six microorganisms. The extracts were potent against Shigella flexneri and Trichophyton tonsurans with minimum inhibitory concentration (MIC) values less than 1 mg/ml. However, there was relatively poor antifungal activity against the other fungal strains. In the DPPH assay, the MeOH extract of the bulb had an EC 50 of 29.8 μg/ml while 76.91% antioxidant activity was observed in the β-carotene-linoleic acid model. The extract contained total phenolics (41 mg GAE/g) and flavonoids (10 mg CE/g). The GC-MS analysis of Hypoxis hemerocallidea bulb revealed 29 and 160 bioactive compounds for 50% MeOH and PE extracts, respectively. Based on the cytotoxicity, Hypoxis hemerocallidea had LC 50 value of 210.9 ± 18.4 and 95.5 ± 13.3 μg/ml for PE and MeOH extracts, respectively., Conclusions: The bulb extracts of Hypoxis hemerocallidea exhibited good antimicrobial and antioxidant activities, which could be attributed to the presence of phenolics, flavonoids and the other bioactive compounds identified through GC-MS, making it a potentially effective cosmetic plant. These findings also account for the multi-pharmacological use of Hypoxis hemerocallidea in traditional medicine, especially related to skin diseases. The plant extracts can be considered as safe based on their LC 50 values (< 20 μg/ml). However, other form of cytotoxicity studies need to be carried out on Hypoxis hemerocallidea, as well as in vivo tests, to confirm its safety and efficacy as a treatment for skin-related diseases., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Although orthodox medications are available for skin diseases, expensive dermatological services have necessitated the use of medicinal plants as a cheaper alternative. This study evaluated the pharmacological and phytochemical profiles of four medicinal plants ( Drimia sanguinea , Elephantorrhiza elephantina , Helichrysum paronychioides , and Senecio longiflorus ) used for treating skin diseases. Petroleum ether and 50% methanol extracts of the plants were screened for antimicrobial activity against six microbes: Bacillus cereus , Shigella flexneri , Candida glabrata , Candida krusei , Trichophyton rubrum and Trichophyton tonsurans using the micro-dilution technique. Antioxidant activity was conducted using 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging and β-carotene linoleic acid models. Cytotoxicity was determined against African green monkey Vero kidney cells based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. Spectrophotometric and Gas Chromatography-Mass Spectrometry (GC-MS) methods were used to evaluate the phytochemical constituents. All the extracts demonstrated varying degrees of antimicrobial potencies. Shigella flexneri , Candida glabrata, Trichophyton rubrum and Trichophyton tonsurans were most susceptible at 0.10 mg/mL. In the DPPH test, EC 50 values ranged from approximately 6-93 µg/mL and 65%-85% antioxidant activity in the β-carotene linoleic acid antioxidant activity model. The phenolic and flavonoid contents ranged from 3.5-64 mg GAE/g and 1.25-28 mg CE/g DW, respectively. The LC 50 values of the cytotoxicity assay ranged from 0.015-5622 µg/mL. GC-MS analysis revealed a rich pool (94-198) of bioactive compounds including dotriacontane, benzothiazole, heptacosane, bumetrizole, phthalic acid, stigmasterol, hexanoic acid and eicosanoic acid, which were common to the four plants. The current findings provide some degree of scientific evidence supporting the use of these four plants in folk medicine. However, the plants with high cytotoxicity need to be used with caution.

Hot water and hydroethanolic (70:30) extracts were prepared from 15 plant species, which were investigated to discover eco-friendly and less expensive tick control methods as an alternative to synthetic acaricides. A contact bioassay was used to determine the acaricidal activity of these extracts against the cattle tick, Rhipicephalus turanicus (Acari: Ixodidae) at a concentration of 20% (200 mg/mL). The hydroethanolic extracts had better activity than the hot water extracts against R. turanicus. The hydroethanolic extract from Tabernaemontana elegans (leaves) had the best mortality (87.0%). This was followed by Calpurnia aurea (stems) with a mortality of 75.0%, Schkuhria pinnata (whole plant) with a mortality of 67.0% and Aloe rupestris (leaves) with a mortality of 66.6%. The toxicity of the plant extracts was also investigated and it was found that most of the hydroethanolic and hot water extracts were either safe or very safe on human Vero kidney and liver HepG2 cells. From this study, it was evident that botanicals have the potential to be developed as environmentally benign natural acaricides against R. turanicus.

Background: Antimicrobial resistance (AMR) remains an important global health issue but the gap between AMR and development of new antimicrobials is increasing. Plant extracts may have good activity per se or may be sources of effective antimicrobial compounds which can act against planktonic and/or biofilms of pathogens. We determined the antimicrobial efficacy and cytotoxicity of some under-investigated plants from the Myrtaceae family endemic to South Africa. The ability of the plant extracts to inhibit or destroy pre-formed bacterial biofilms was also determined., Methods: Based on previous preliminary in vitro screening and on chemotaxonomy, nine species from the Myrtaceae family were selected. The antimicrobial activity of the crude acetone leaf extracts was determined against six common nosocomial pathogens, namely: Gram-positive bacteria (Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus), Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella Typhimurium) using a two-fold serial microdilution assay with p-iodonitrotetrazolium violet as growth indicator. The number of antimicrobial compounds present in extracts was determined by bioautography. Cytotoxicity of extracts was determined against Vero kidney cells using a colorimetric tetrazolium-based assay. The total antibacterial activity (TAA) in ml/g and selectivity index (LC 50 /MIC) of the plant extracts were calculated. A modified crystal violet assay was used to determine the antibiofilm activity of the extracts., Results: Syzygium legatii, Syzygium masukuense, and Syzygium species A had the best activities against Gram-negative and Gram-positive bacteria (MIC) values ranging from 0.04-0.08 mg/ml. Eugenia erythrophylla had the best MIC (0.02 mg/ml) against Bacillus cereus. Many extracts had relatively low cytotoxicity (LC 50  > 20 μg/ml) leading to reasonable selectivity indices. Three leaf extracts (Syzygium masukuense, Syzygium species A, and Eugenia natalitia) were moderately cytotoxic (20 μg/ml < LC 50  < 100 μg/ml). The plant extracts had a good capacity to reduce biofilm formation and good to poor potential to destroy pre-formed biofilms., Conclusions: The plant species examined in this study had varying degrees of antibacterial activity against bacterial planktonic and biofilm forms with some having good activity against both forms. Several of these selected species may be potential candidates for further investigation to isolate antimicrobial compounds and to determine the mechanism of activity.

Background: Diarrhoea, a global economically important disease burden affecting swine and, especially piglets, is commonly caused by infection with entero-toxigenic E. coli (ETEC). Adherence of ETEC to porcine intestinal epithelial cells following infection, is necessary for its pathogenesis. While antimicrobials are commonly given as therapy or as feed additives for prophylaxis against microbial infections, the concern over increased levels of antimicrobial resistance necessitate the search for safe and effective alternatives in livestock feed. Attention is shifting to natural products including plants as suitable alternatives to antimicrobials. The activity of acetone crude leaf extracts of nine under-explored South African endemic plants from the Myrtaceae family with good antimicrobial activity were tested against pathogenic E. coli of porcine origin using a microplate serial dilution method. Bioautography, also with p-iodonitrotetrazolium violet as growth indicator was used to view the number of bioactive compounds in each extract. In vitro toxicity of extracts was determined against Caco-2 cells using the 3-(4,5-dimethythiazolyl-2)-2,5-diphenyltetrazolium bromide reduction assay. The antimicrobial susceptibility of E. coli isolates was tested on a panel of antimicrobials using the Kirby-Bauer agar diffusion method while the anti-adherence mechanism was evaluated using a Caco-2 cell enterocyte anti-adhesion model., Results: The MIC of the extracts ranged from 0.07-0.14 mg/mL with S. legatii having the best mean MIC (0.05 mg/mL). Bioautography revealed at least two active bands in each plant extract. The 50% lethal concentration (LC 50 ) values ranged between 0.03-0.66 mg/mL. Eugenia zeyheri least cytotoxic (LC 50  = 0.66 mg/ml) while E. natalitia had the highest cytotoxicity (LC 50  = 0.03 mg/mL). All the bacteria were completely resistant to doxycycline and colistin sulphate and many of the plant extracts significantly reduced adhesion of E. coli to Caco-2 cells., Conclusions: The extracts of the plants had good antibacterial activity as well as a protective role on intestinal epithelial cells against enterotoxigenic E. coli bacterial adhesion. This supports the potential use of these species in limiting infection causes by E. coli. Some of these plants or extracts may be useful as phytogenic feed additives but it has to be investigated by animal feed trials.

Background: Tuberculosis is a deadly disease caused by Mycobacterium species. The use of medicinal plants is an ancient global practice for the treatment and prevention of diverse ailments including tuberculosis. The aim of this study was to isolate and characterize antimycobacterial compounds by bioassay-guided fractionation of the acetone leaf extract of Oxyanthus speciosus., Methods: A two-fold serial microdilution method was used to determine the minimum inhibitory concentration (MIC) against mycobacteria. Cytotoxicity and nitric oxide inhibitory activity of the isolated compounds was determined to evaluate in vitro safety and potential anti-inflammatory activity. Intracellular efficacy of the crude extract against Mycobacterium-infected macrophages was also determined., Results: Two compounds were isolated and identified as lutein (1) and rotundic acid (2). These had good antimycobacterial activity against the four mycobacteria tested with MIC values ranging from 0.013 to 0.1 mg/mL. Rotundic acid had some cytotoxicity against C3A human liver cells. Lutein was not cytotoxic at the highest tested concentration (200 μg/mL) and inhibited nitric oxide production in RAW 264.7 macrophages by 94% at a concentration of 25 μg/mL. The acetone crude extract (120 μg/mL) of O. speciosus had intracellular antimycobacterial activity, reducing colony forming units by more than 90%, displaying bactericidal efficacy in a dose and time-dependent manner., Conclusion: This study provides good proof of the presence of synergism between different compounds in extracts and fractions. It is also the first report of the antimycobacterial activity of lutein and rotundic acid isolated from Oxyanthus speciosus. The promising activity of the crude extract of O. speciosus both in vitro and intracellularly in an in vitro macrophage model suggests its potential for development as an anti- tuberculosis (TB) herbal medicine.

The WHO has stated that antibiotic resistance is escalating to perilously high levels globally and that traditional therapies of antimicrobial drugs are futile against infections caused by resistant microorganisms. Novel antimicrobial drugs are therefore required. We report in this study on the inhibitory activity of the 1,4-naphthoquinone-2,3-bis-sulfides and 1,4-naphthoquinone sulfides against two bacteria and a fungus to determine their antimicrobial properties. The 1,4-naphthoquinone sulfides have potent activity with a minimum inhibitory concentration (MIC) of 7.8 μg/mL against Staphylococcus aureus (Gram +ve), an MIC of 23.4 μg/mL against the fungus, Candida albicans, which was better than that of Amphotericin B (MIC = 31.3 μg/mL), and against Escherichia coli (Gram -ve) an MIC of 31.3 μg/mL was obtained. The 1,4-naphthoquinone had an MIC of 11.7 μg/mL against S. aureus and the 1,4-naphthohydroquinone also had the same activity against E. coli. Hit, Lead & Candidate Discovery., (© 2019 Wiley Periodicals, Inc.)

Ethnopharmacological Relevance: Inflammation is a complex mechanism employed by the body to promote healing and restoration to normal function in the event of injury. Eleven plant species were selected in this study based on their use in traditional medicine against inflammation in South Africa., Methods: Hexane, acetone, ethanol, methanol and water extracts of the powdered plants were prepared and a total of fifty-five extracts were tested for their anti-inflammatory and antioxidant activities. The anti-inflammatory activity of extracts was evaluated via the 15-lipoxygenase (15-LOX) inhibitory and the nitric oxide (NO) inhibition assays using lipopolysaccharide (LPS)-activated RAW 264.7 murine macrophages. Total flavonoid and total phenolic contents were determined. The antioxidant activity of the extracts was performed using radical scavenging DPPH (2, 2-diphenyl-1-picrylhydrazyl) and electron reducing ABTS (2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) assays., Results: The hexane extract of Typha capensis (TC) had good lipoxygenase inhibitory activity with IC 50 of 4.65 µg/mL, significantly (p < 0.05) higher than that of the positive control quercetin (IC 50 = 24.60). The same extract also had good nitric oxide inhibitory activity with 86% NO inhibition and cell viability of 97% at 50 µg/mL. The TC acetone extract had the best antioxidant activity with IC 50 of 7.11 and 1.91 µg/mL respectively in the DPPH and ABTS assays. Following fractionation of the TC plant material, the ethyl acetate fraction had interesting antioxidant activity and the methanol/water (35%) and hexane fractions had good 15-LOX inhibitory activity. The antioxidant and anti-inflammatory activities therefore resided in both polar and more non-polar fractions., Conclusion: The acetone extract of Typha capensis and its fractions had good anti-inflammatory and antioxidant activities, supporting the medicinal use of this species against inflammation. Other species including Ficus elastica, Carpobrotus edulis, Cotyledon orbiculata and Senna italica also had good activity worthy of further investigation., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Tuberculosis (TB), a disease caused by microorganisms of the Mycobacterium tuberculosis complex, infects almost one-third of the world's population. The TB epidemic has been further exacerbated by the emergence of multi, extensively, and totally-drug-resistant (MDR, XDR, and TDRTB) strains. An effective immune response plays a crucial role in determining the establishment of TB infection. Therefore, the modulation of the immune system has been considered as a vital approach for the treatment or control of various immune-related diseases such as TB. In this study, the antimycobacterial, immunomodulatory, and apoptosis-inducing effects of six Rubiaceae species were evaluated. A twofold serial dilution method was used to determine the minimum inhibitory concentration values of the plant extracts. The effect of the extracts on the activity of 15-lipoxygenase was investigated. The levels of six different cytokines, IL-2, IL-4, IL-5, IL-10, IFN-γ, and TNF-α, were measured in LPS-activated U937 cell line while the apoptosis-inducing effect of the extracts was evaluated using an annexin V/PI assay using a flow cytometer. The results obtained revealed that all the six extracts tested had antimycobacterial activity against M. tuberculosis H37Rv, M. tuberculosis ATCC 25177, and Mycobacterium bovis ATCC 27299 strains, with MIC values ranging from 39 to 312 μg/mL. The extracts of Cremaspora triflora and Cephalanthus natalensis were the most active against M. tuberculosis (MIC = 39 μg/mL), followed by Pavetta lanceolata and Psychotria zombamontana against M. bovis (MIC = 78 μg/mL). The extracts of P. zombamontana and Psychotria capensis had remarkable IC 50 values of 4.32 and 5.8 μg/mL, respectively, better than that of quercetin. The selected extracts promoted Th1/Th2 balances in an in vitro model at the tested concentration which may suggest the therapeutic value of the plant in diseases where inflammation is a significant factor such as TB. The addition of the crude extracts of C. triflora , P. capensis , and P. zombamontana at the tested concentrations to the cell culture medium induced apoptosis in a time- and dose-dependent manner. This interesting preliminary result generated from this study encourages further investigations of these extracts owing to the LOX-inhibitory effect, immunomodulatory, and apoptotic-inducing properties in addition to their antimycobacterial properties.

In this study, we report on the inhibitory activity of synthesized aminonaphthoquinones against two bacterial and one fungal species to determine their antimicrobial properties. A minimum inhibitory concentration (MIC) of 7.8 μg/mL was obtained against the fungus, Candida albicans, which was better than that of Amphotericin B (MIC = 31.25 μg/mL). Escherichia coli (Gram -), was inhibited at a MIC of 23.4 μg/mL and Staphylococcus aureus (Gram +) at a MIC of 31.3 μg/mL. The aminonaphthoquinones were also screened against HCT116 colon, PC3 prostate and HepG2 liver cancer cell lines to evaluate their cytostatic effects. They had potent activity (GI 50  = 5.87-9.90 μM) which was about three-6-fold better than that of parthenolide (GI 50  = 25.97 μM) against the prostate cancer cell line. These compounds were generally more selective for cancer cells than for normal human lung fetal fibroblasts (WI-38)., (© 2018 Wiley Periodicals, Inc.)