Search

The need to explore the abundance of natural products cannot be overemphasized particularly in the management of various disease conditions. In traditional medical practice, Vernonia amygdalina has been widely adopted in the management of various inflammatory disorders. The objective of this investigation was to isolate the bioactive principles from the stem-bark and root of V. amygdalina and assess the anti-inflammatory ( in vitro ) activity of both the crude extracts and the isolated compounds. Following extraction with the methanol, the extract was subjected to gravity column chromatography and the resultant fractions was further purified to obtained pure compounds. The structural elucidation of the compounds were based on data obtained from 1H to 13C nuclear magnetic resonance (NMR) spectroscopies as well as fourier transform infrared (FT-IR). Using diclofenac as a control drug, the albumin denaturation assay was used to determine the in vitro anti-inflammatory activity of the extracts and isolates. Three distinct compounds characterized are vernoamyoside D, luteolin-7-α-o-glucuronide, and vernotolaside, a new glycoside. When compared to diclofenac, which has an IC 50 of 167.8 μg/mL, luteolin-7-α-o-glucuronide, vernoamyoside D, and vernotolaside all showed significant inhibitions with respective IC 50 values 549.8, 379.5, and 201.7 μg/mL. Vernotolaside is reported for the first time from the root. The assertion that the plant is used in traditional medicine for the management of inflammatory disorder is somewhat validated by the confirmation of the existence of the compounds with the biochemical actions. Further validation of the isolated compounds would be required in animal studies., Competing Interests: 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., (© 2024 The Authors.)

This study aimed to assess the antioxidant, enzyme inhibitory, physicochemical and sensory properties of instant bio-yoghurts containing multi-purpose natural additives. Multi-purpose natural additives were formulated with three natural additives (sweet detar seed, ginger rhizome, and hibiscus calyx flours, as a thickener, flavourant and colourant, respectively) blends at proportions derived from the Design Expert. The additives' synthetic counterparts were formulated with sodium carboxymethylcellulose, vanilla flavor, and red colourant at the same proportions. After that, yoghurt was produced and the additives blends were incorporated into it either in aqueous extract or flour form, yielding bio-yoghurts designated multi-purpose natural additive extract-containing yoghurt (MNAE-yoghurt), multi-purpose natural additive flour-added yoghurt (MNAF-yoghurt), and their multi-purpose synthetic additives-containing counterparts (MSAE-yoghurt and MSAF-yoghurt). A commercially-available bio-yoghurt served as a control. All the yoghurts were lyophilized to obtain instant bio-yoghurts. Subsequently, bioactive components (total phenolics, tannins, total flavonoids and saponins), antioxidants and enzymes [alpha-amylase, alpha-glucosidase, pancreatic lipase, and angiotensin 1-converting enzyme (ACE)] inhibitory activities, as well as proximate, physicochemical and sensory qualities of the bio-yoghurts were determined. The MNAE-yoghurt and MNAF-yoghurt had higher bioactive constituents, total titratable acid levels, and more potent antioxidant and enzyme inhibitory properties, but a lower pH than their synthetic counterparts and the control. The total phenolics, tannins, total flavonoids and saponins levels of MNAE-yoghurt and MNAF-yoghurt were 14.40 ± 0.24 and 16.54 ± 0.62 mg/g, 1.65 ± 0.04 and 1.74 ± 0.08 mg/g, 4.25 ± 0.03 and 4.40 ± 0.02 mg/g, 0.64 ± 0.01 and 0.66 ± 0.02 mg/g, respectively. Among the natural multi-purpose additives-containing bio-yoghurts, MNAF-yoghurt had higher bioactive constituents and stronger antioxidant and enzymes inhibitory properties. Its α-amylase, α-glucosidase, ACE, and pancreatic lipase IC 50 values were 72.47 ± 0.47, 74.07 ± 0.02, 25.58 ± 2.58, and 33.56 ± 29.66 μg/mL, respectively. In contrast, MNAE-yoghurt had the highest protein (13.70 ± 0.85%) and the lowest fat (2.63 ± 0.71%) contents. The sensory attributes of all the bio-yoghurts fell within an acceptable likeness range. Overall, the inclusion of multi-purpose natural additives blends enhanced the instant bio-yoghurts' nutritional, health-promoting, and sensory qualities., 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 © 2024 Irondi, Bankole, Awoyale, Ajani and Alamu.)

Yogurt, a popular fermented dairy product, is of different types and known for its nutritional and nutraceutical benefits. However, incorporating additives into yogurt has been adopted to improve its functionality and nutraceutical properties. Additives incorporated in yogurt may be natural or modified. The incorporation of diverse natural additives in yogurt formulation, such as moringa, date palm, grape seeds and argel leaf extracts, cornelian cherry paste, mulberry fruit and leaf powder, lentil flour, different types of fibers, lemongrass and spearmint essential oils, and honey, has been reported. Similarly, modified additives, such as β-glucan, pectin, inulin, sodium alginate, and gelatin, are also added to enhance the physicochemical, textural, sensory, and rheological properties of yogurt. Although additives are traditionally added for their technological impact on the yogurt, studies have shown that they influence the nutritional and nutraceutical properties of yogurt, when added. Hence, yogurts enriched with functional additives, especially natural additives, have been reported to possess an improved nutritional quality and impart several health benefits to consumers. These benefits include reducing the risk of cardiovascular disease, cancer, osteoporosis, oxidative stress, and hyperglycemia. This current review highlights the common types of yogurt, the production process, and the rheological and nutraceutical benefits of incorporating natural and modified additives into yogurt., 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 Bankole, Irondi, Awoyale and Ajani.)

Malaria is a devastating disease, and its management is only achieved through chemotherapy. However, resistance to available medication is still a challenge; therefore, there is an urgent need for the discovery and development of therapeutics with a novel mechanism of action to counter the resistance scourge consistent with the currently available antimalarials. Recently, plasmepsin V was validated as a therapeutic target for the treatment of malaria. The pepsin-like aspartic protease anchored in the endoplasmic reticulum is responsible for the trafficking of parasite-derived proteins to the erythrocytic surface of the host cells. In this study, a small library of compounds was preliminarily screened in vitro to identify novel modulators of Plasmodium falciparum plasmepsin V ( Pf PMV). The results obtained revealed kaempferol, quercetin, and shikonin as possible Pf PMV inhibitors, and these compounds were subsequently probed for their inhibitory potentials using in vitro and in silico methods. Kaempferol and shikonin noncompetitively and competitively inhibited the specific activity of Pf PMV in vitro with IC 50 values of 22.4 and 43.34  μ M, respectively, relative to 62.6  μ M obtained for pepstatin, a known aspartic protease inhibitor. Further insight into the structure-activity relationship of the compounds through a 100 ns molecular dynamic (MD) simulation showed that all the test compounds had a significant affinity for Pf PMV, with quercetin (-36.56 kcal/mol) being the most prominent metabolite displaying comparable activity to pepstatin (-35.72 kcal/mol). This observation was further supported by the compactness and flexibility of the resulting complexes where the compounds do not compromise the structural integrity of Pf PMV but rather stabilized and interacted with the active site amino acid residues critical to Pf PMV modulation. Considering the findings in this study, quercetin, kaempferol, and shikonin could be proposed as novel aspartic protease inhibitors worthy of further investigation in the treatment of malaria., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2023 Abdulhakeem Olarewaju Sulyman et al.)

Yellow-fleshed cassava root (YFCR) is processed into traditional products that may influence its bioactivities. In this study, the antioxidant and anti-hyperglycaemic activities of three traditional products ( lafun, fufu and gari ) from five genotypes (IITA-TMS-IBA070337, 182961, 182962, 182986, 183044) of YFCR were evaluated. The YFCR genotypes were grown at the International Institute of Tropical Agriculture (IITA) research field, Ibadan. The bioactive constituents (total carotenoids, total phenolics, tannins and total flavonoids), antioxidant [2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) radical cation (ABTS •+ ) and 1,1-diphenyl-2- picrylhydrazyl radical (DPPH • ) scavenging capacities, and reducing power], and starch-digesting enzymes (α-amylase and α-glucosidase) inhibitory activities of the products were determined using standard laboratory methods. The glucose response of the products was assessed in human subjects. The concentrations of the bioactive constituents of the products from different genotypes varied significantly ( p < 0.05). The ABTS •+ and DPPH • scavenging capacities and the reducing power of the products also differed significantly ( p < 0.05), such that the lafun from IITA-TMS-IBA182962, IITA-TMS-IBA070337 and IITA-TMS-IBA070337 had the strongest ABTS •+ and DPPH • scavenging capacities, and reducing power, respectively. The α-amylase and α-glucosidase inhibitory activities of the three products differed significantly ( p < 0.05), with the lafun from IITA-TMS-IBA070337 and IITA-TMS-IBA07033 having the strongest α-amylase and α-glucosidase inhibitory activity, respectively. Also, the lafun from IITA-TMS-182986 had the least glucose response, while the fufu from IITA-TMS-IBA070337 had the highest glucose response. Overall, the lafun from different genotypes of YFCR had the most potent antioxidant and starch-digesting enzymes inhibitory activities and the least glucose responses. Hence, lafun may be a promising dietary intervention targeting oxidative stress, hyperglycaemia, and their resultant type 2 diabetes., 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 Kareem, Irondi, Alamu, Ajani, Abass, Adesokan, Parkes and Maziya-Dixon.)

Most of the health benefits derived from cereals are attributed to their bioactive compounds. This study evaluated the levels of the bioactive compounds, and the antioxidant and starch-hydrolyzing enzymes inhibitory properties of six pipeline Striga -resistant yellow-orange maize hybrids (coded AS1828-1, 4, 6, 8, 9, 11) in vitro. The maize hybrids were grown at the International Institute of Tropical Agriculture (IITA), Nigeria. The bioactive compounds (total phenolics, tannins, flavonoids, and phytate) levels, antioxidant (DPPH • and ABTS •+ scavenging capacity and reducing power) and starch-hydrolyzing enzymes (α-amylase and α-glucosidase) inhibitory activities of the maize hybrids were determined by spectrophotometry. At the same time, carotenoids were quantified using a reverse-phase HPLC system. The ranges of the bioactive compounds were: 11.25-14.14 mg GAE/g (total phenolics), 3.62-4.67 mg QE/g (total flavonoids), 3.63-6.29 mg/g (tannins), 3.66-4.31% (phytate), 8.92-12.11 µg/g (total xanthophylls), 2.42-2.89 µg/g (total β-carotene), and 3.17-3.77 µg/g (total provitamin A carotenoids). Extracts of the maize hybrids scavenged DPPH • (SC 50 : 9.07-26.35 mg/mL) and ABTS •+ (2.65-7.68 TEAC mmol/g), reduced Fe 3+ to Fe 2+ (0.25 ± 0.64-0.43 ± 0.01 mg GAE/g), and inhibited α-amylase and α-glucosidase, with IC 50 ranges of 26.28-52.55 mg/mL and 47.72-63.98 mg/mL, respectively. Among the six clones of the maize hybrids, AS1828-9 had the highest ( p < 0.05) levels of tannins and phytate and the strongest antioxidant and starch-hydrolyzing enzymes inhibitory activities. Significant correlations were observed between total phenolics and the following: ABTS •+ ( p < 0.01, r = 0.757), DPPH • SC 50 ( p < 0.01, r = -0.867), reducing power ( p < 0.05, r = 0.633), α-amylase IC 50 ( p < 0.01, r = -0.836) and α-glucosidase IC 50 ( p < 0.05, r = -0.582). Hence, the Striga -resistant yellow-orange maize hybrids (especially AS1828-9) may be beneficial for alleviating oxidative stress and postprandial hyperglycemia.

Diabetes mellitus (DM) has become a global scourge, and there is a continuous search for novel compounds as viable alternatives to synthetic drugs which are often accompanied by severe adverse effects. Aristolochia ringens is among the scientifically implicated botanicals effective in the management of several degenerative diseases including DM. The current study evaluated the inhibitory mechanism(s) of root extract of A. ringens on α -amylase and α -glucosidase in vitro and in silico , while its constituents were characterized using liquid chromatography-mass spectrometric technique. The extract had concentration-dependent inhibitory effect on the study enzymes, and the inhibition compared well with that of standard drug (acarbose) with respective IC 50 values of 0.67 mg/mL ( α -amylase) and 0.57 mg/mL ( α -glucosidase) compared with that of the extract (0.63 and 0.54 mg/mL). The extract competitively and uncompetitively inhibited α -amylase and α -glucosidase, respectively. Of the identified compounds, dianoside G (-12.4, -12.5 kcal/mol) and trilobine (-10.0, -10.0 kcal/mol) had significant interactions with α -amylase and α -glucosidase, respectively, while magnoflorine and asiatic acid also interacted keenly with both enzymes, with quercetin 3-O-glucuronide and strictosidine showing better affinity towards α -glucosidase. These observations are suggestive of involvement of these compounds as probable ligands contributing to antidiabetic potential of the extract. While studies are underway to demystify the yet to be identified compounds in the extract, the data presented have lent scientific credence to the acclaimed in vivo antidiabetic potential of the extract and suggested it as a viable source of oral hypoglycaemic agent., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this article., (Copyright © 2021 J. B. Ahmad et al.)

This study validates the antidiabetic efficacy of Enantia chlorantha stem bark and the possible therapeutic implications of the co-administration of lisinopril and E. chlorantha in type 2 diabetic rats. E. chlorantha stem bark was extracted by cold maceration. The inhibitory effect of the plant on carbohydrate metabolizing enzymes and its antioxidative potentials were assessed in vitro. The extract exhibited α-amylase and α-glucosidase inhibitory activities and also showed antioxidative properties in vitro. Administration of the extract normalized fasting hyperglycemia in vivo by showing 47.24 % reduction in blood glucose levels relative to untreated diabetic rats. Co-administration of E. chlorantha and lisinopril restored serum glucose and serum lipid profile levels. E. chlorantha stem bark displayed antidiabetic potentials as compared with a standard antidiabetic drug (metformin). The study also showed that the plant contained some bioactive compounds which we hypothesize might be responsible for the observed activities. Co-administration of the plant with lisinopril conferred no significant therapeutic advantage on the serum glucose level and lipid profile.

Background: Food and herbal usage of Hibiscus sabdariffa (HS) is attaining improved global relevance and acceptance without recourse to its potential toxic effects. This study investigated the safety profile of acute, sub-acute, sub-chronic administrations and diuretic potential of aqueous extract of Hibiscus sabdariffa calyces (AEHSC)., Method: Acute oral toxicity, sub-acute and sub-chronic toxicity as well as diuretic studies were carried out on HS. A total of 20 Wistar rats were used for each toxicity study and assigned into four groups of five rats. The extract was administered as a single daily dose of 125, 250 and 500 mg/kg body weight (bwt) for 28 and 90 days respectively. To evaluate diuretic activity, 25 rats were divided into five groups of five rats and administered normal saline, hydrochlorothiazide 10 mg/kg, AEHSC 67.5, 125 and 250 mg/kg via the oral route. Urine sample was collected after 18 h, volume measured and concentration of electrolytes analyzed. The hematological and biochemical parameters were evaluated as well as the histopathology of kidney and liver., Results: The acute oral toxicity was found to be >2000 mg/kg. AEHSC did not alter concentration of WBC, MCV, MCHC, lymphocyte as well as total and direct bilirubin in the sub-acute study. However, AEHSC significantly (p < 0.05) increased total protein, albumin, globulin, Na + , Cl - , HCO 3 - and platelet levels, while levels of uric acid, creatinine, K + , RBC, Hb, total cholesterol, triglycerides, LDL-C, HDL-C and atherogenic index were decreased significantly (p < 0.05). In the sub-chronic study, AEHSC significantly (p < 0.05) increased the levels of globulin, urea, creatinine, MCH and atherogenic index. The concentrations of uric acid, WBC, platelets and HDL-C were significantly (p < 0.05) decreased. In both the sub-acute and sub-chronic studies, activities of ALP, ALT, AST, GGT and LDH in selected organs were altered without significant increase (P < 0.05) in activity of these enzymes in the serum. The AEHSC at all the doses showed remarkable diuretic activity during 18 h period comparable to hydrochlorothiazide. The extract also showed a non-dose-dependent increase in excretion of electrolytes. Histological analysis of sections of the liver and kidney for both sub-acute and sub-chronic studies showed normal histology comparable to the control group., Conclusion: This study revealed AEHSC has some toxic effects in rats on sub-chronic administration. In addition, the extracts produced a significant diuretic activity. Hence, prolonged oral consumption of the extract may not be recommended., (© 2020 The Authors.)