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This study investigates the physicochemical, mineral, proximate, FTIR, and SEM analysis of the gums obtained from the bark of Terminalia mantaly and Khaya senegalensis. The physicochemical analysis for Terminalia mantaly gum (TMG) gave values of 30.76 %, 4.50, 0.10 g/cm³, 0.142 mg/cm³, 8.78 %, and 10.55 % for percentage yield, pH, bulk density, tapped density, swelling index and water absorption capacity respectively while 29.50 %, 4.80, 0.12 g/cm³, 0.105 mg/cm³, 8.45 %, and 10.27 % for percentage yield, pH, bulk density, tapped density, swelling index and water absorption capacity respectively were recorded for Khaya senegalensis gum (KSG). The results of the proximate analysis showed that TMG had a higher percentage of moisture content, crude fat and ash content than KSG, and KSG had a higher percentage of crude fibre, crude protein, and carbohydrate content than TMG. Elemental analysis for Terminalia mantaly gum (TMG) gave values of 58.50 mg/kg, 42.0 mg/kg, 11.30 mg/kg, 38.50 mg/kg, 2.58 mg/kg, 1.53 mg/kg, and 0.33 mg/kg for potassium, magnesium, sodium, calcium, zinc, iron, and copper respectively while 58.00 mg/kg, 41.60 mg/kg, 39.00 mg/kg, 10.50 mg/kg, 1.50 mg/kg, 2.34 mg/kg, and 0.30 mg/kg for potassium, magnesium, calcium, sodium, iron, zinc, and copper respectively were recorded for Khaya senegalensis gum (KSG). The results show no toxicity and high nutritional and mineral value of the gums. Thus, they are safe to be used in the pharmaceutical and food industries. [ABSTRACT FROM AUTHOR]

In this study, we tested the biosorption capacity of trimethyl chitosan (TMC)-ZnO nanocomposite (NC) for the adsorptive removal of Escherichia coli (E. coli) in aqueous suspension. For the formation of ZnO NPs, we followed the green synthesis route involving Terminalia mantaly (TM) aqueous leaf extract as a reducing agent, and the formed ZnO particles were surface-coated with TMC biopolymer. On testing of the physicochemical characteristics, the TM@ZnO/TMC (NC) hydrogel showed a random spherical morphology with an average size of 31.8 ± 2.6 nm and a crystal size of 28.0 ± 7.7 nm. The zeta potential of the composite was measured to be 23.5 mV with a BET surface area of 3.01 m2 g−1. The spectral profiles of TM@ZnO/TMC NC hydrogel on interaction with Escherichia coli (E. coli) revealed some conformational changes to the functional groups assigned to the stretching vibrations of N-H, C-O-C, C-O ring, and C=O bonds. The adsorption kinetics of TM@ZnO/TMC NC hydrogel revealed the pseudo-second-order as the best fit mechanism for the E. coli biosorption. The surface homogeneity and monolayer adsorption of the TM@ZnO/TMC NC hydrogel reflects majorly the entire adsorption mechanism, observed to display the highest correlation for Jovanovic, Redlich–Peterson, and Langmuir's isotherm models. Further, with the use of TM@ZnO/TMC NC hydrogel, we measured the highest adsorption capacity of E. coli to be 4.90 × 10 mg g−1, where an in-depth mechanistic pathway was proposed by making use of the FTIR analysis. [ABSTRACT FROM AUTHOR]

Highlights: • Malaria is prevalent in many populations of communities despite preventive measures. • The experimental was screened for bioactive components which could be the reason for the antimalarial effect and the plant shows dose dependent antimalarial activity. Abstract : Malaria has been one of the world’s worst killer diseases throughout recorded human history. Despite attempts to eradicate the disease, it remains a global burden. This could be a result of parasite resistance to current therapy. However, this research aimed at evaluating the in vitro antimalarial activity of ethanolic extracts of Terminalia mantaly on Plasmodium falciparum. The plant extracts were prepared by cold maceration in 70% ethanol and air-dried by a rotary evaporator. The phytochemical analysis was carried out using standard procedures outlined in the Analytical methods of the Association of Official Analytical Chemists (AOAC, 1990) which indicates the presence of tannins, alkaloids, saponins, flavonoids, glycosides, phenol, steroids, and balsam. The in vitro antimalarial assay was carried out according to the method described by WHO (2001). All data were represented as Mean ± Standard deviation. Ethanolic extracts of the three parts of the plant were subjected to in vitro antimalarial activity at three concentrations (300 mg, 150 mg, and 75 mg) in four replicates with artemether (standard drug) as a positive control. Stem bark at 300 mg/kg completely cleared the parasites with a 0.00% parasitaemia rate and there was no significant difference when compared with positive control at p

Malaria has been one of the world's worst killer diseases throughout recorded human history. Despite attempts to eradicate the disease, it remains a global burden. This could be a result of parasite resistance to current therapy. However, this research aimed at evaluating the in vitro antimalarial activity of ethanolic extracts of Terminalia mantaly on Plasmodium falciparum. The plant extracts were prepared by cold maceration in 70% ethanol and air-dried by a rotary evaporator. The phytochemical analysis was carried out using standard procedures outlined in the Analytical methods of the Association of Official Analytical Chemists (AOAC, 1990) which indicates the presence of tannins, alkaloids, saponins, flavonoids, glycosides, phenol, steroids, and balsam. The in vitro antimalarial assay was carried out according to the method described by WHO (2001). All data were represented as Mean ± Standard deviation. Ethanolic extracts of the three parts of the plant were subjected to in vitro antimalarial activity at three concentrations (300 mg, 150 mg, and 75 mg) in four replicates with artemether (standard drug) as a positive control. Stem bark at 300 mg/kg completely cleared the parasites with a 0.00% parasitaemia rate and there was no significant difference when compared with positive control at p<0.005 value of 1.00. This study affirms the use of the plant for the treatment of malaria. [ABSTRACT FROM AUTHOR]

In this study, we tested the biosorption capacity of trimethyl chitosan (TMC)-ZnO nanocomposite (NC) for the adsorptive removal of Escherichia coli (E. coli) in aqueous suspension. For the formation of ZnO NPs, we followed the green synthesis route involving Terminalia mantaly (TM) aqueous leaf extract as a reducing agent, and the formed ZnO particles were surface-coated with TMC biopolymer. On testing of the physicochemical characteristics, the TM@ZnO/TMC (NC) hydrogel showed a random spherical morphology with an average size of 31.8 ± 2.6 nm and a crystal size of 28.0 ± 7.7 nm. The zeta potential of the composite was measured to be 23.5 mV with a BET surface area of 3.01 m2 g−1. The spectral profiles of TM@ZnO/TMC NC hydrogel on interaction with Escherichia coli (E. coli) revealed some conformational changes to the functional groups assigned to the stretching vibrations of N-H, C-O-C, C-O ring, and C=O bonds. The adsorption kinetics of TM@ZnO/TMC NC hydrogel revealed the pseudo-second-order as the best fit mechanism for the E. coli biosorption. The surface homogeneity and monolayer adsorption of the TM@ZnO/TMC NC hydrogel reflects majorly the entire adsorption mechanism, observed to display the highest correlation for Jovanovic, Redlich–Peterson, and Langmuir’s isotherm models. Further, with the use of TM@ZnO/TMC NC hydrogel, we measured the highest adsorption capacity of E. coli to be 4.90 × 10 mg g−1, where an in-depth mechanistic pathway was proposed by making use of the FTIR analysis.

Michele Stella Majoumouo,1,2 Nicole Remaliah Samantha Sibuyi,2 Marius Belmondo Tincho,2 Michele Mbekou,1 Fabrice Fekam Boyom,1 Mervin Meyer2 1Antimicrobial & Biocontrol Agents Unit, Laboratory for Phytobiochemistry and Medicinal Plants Studies, Department of Biochemistry, University of Yaoundé 1, Yaoundé, Cameroon; 2Department of Science and Technology (DST)/Mintek Nanotechnology Innovation Centre, Biolabels Node, Department of Biotechnology, University of the Western Cape, Bellville, South AfricaCorrespondence: Mervin MeyerUniversity of the Western Cape, Department of Biotechnology, New Life Science Building, Robert Sobukwe Road, Bellville 7535, South AfricaTel +27 21 9592032Fax +27 21 9593505Email memeyer@uwc.ac.zaBackground: The global increase in outbreaks and mortality rates associated with multi-drug-resistant (MDR) bacteria is a major health concern and calls for alternative treatments. Natural-derived products have shown potential in combating the most dreadful diseases, and therefore serve as an effective source of bioactive compounds that can be used as anti-bacterial agents. These compounds are able to reduce metal ions and cap nanoparticles to form biogenic nanoparticles (NPs) with remarkable anti-bacterial activities. This study explores the use of Terminalia mantaly (TM) extracts for the synthesis of biogenic silver NPs (TM-AgNPs) and the evaluation of their antibacterial activity.Methods: TM-AgNPs were synthetized by the reduction of AgNO3 with aqueous and methanolic TM extracts. UV–visible (UV-vis) spectrophotometry, Dynamic Light Scattering (DLS), Transmission Electron Microscopy, and Fourier Transform Infrared (FTIR) analyses were used to characterise the TM-AgNPs. Anti-bacterial activity of the TM extracts and TM-AgNPs was evaluated against eight bacterial strains using the broth microdilution assay. The growth inhibitory kinetics of the bio-active TM-AgNPs was assessed on susceptible strains for a period of 8 hrs.Results: Polycrystalline biogenic AgNPs with anisotropic shapes and diameter range of 11 to 83 nm were synthesized from the TM extracts. The biogenic TM-AgNPs showed significant antibacterial activity compared to their respective extracts. The MIC values for TM-AgNPs and extracts were 3 and 125 μg/mL, respectively. Biogenic AgNPs synthesised from the aqueous TM leaf extract at 25°C (aTML-AgNPs-25°C) showed significant antibacterial activity against all the bacterial strains tested in this study. Their bactericidal effect was particularly higher against the Streptococcus pneumoniae and Haemophilus influenzae.Conclusion: This study demonstrated the ability of TM extracts to synthesize biogenic AgNPs. The NPs synthesized from the aqueous TM extracts demonstrated higher antibacterial activity against the tested microorganisms compared to the methanolic extracts. Studies are underway to identify the phytochemicals involved in NP synthesis and their mechanism of action.Keywords: antimicrobial resistance, green synthesis, nanotechnology, Terminalia mantaly, antibacterial activity

Terminaliamide (1), a new ceramide was isolated from the roots of Terminalia mantaly H. Perrier (Combretaceae) along with 4 known compounds (2–5). The structures of the compounds were elucidated using 1D and 2D NMR spectroscopy analysis and mass spectrometry. Compound 1 exhibited moderated antibacterial activity towards Staphylococcus aureus with MIC value of 62.5 μg/mL. The crude MeOH extract (TMr) highly reduced Plasmodium falciparum growth with an IC50 value of 10.11 μg/mL, while hexane fraction (F1) highly reduced Trypanosoma brucei brucei growth with an IC50 value of 5.60 µg/mL. All tested samples presented little or no in vitro cytotoxicity on HeLa cell line. The present work confirms that T. mantaly is medicinally important and may be used effectively as an antimicrobial, an antiplasmodial and an antitrypanosomial with promising therapeutic index. [ABSTRACT FROM AUTHOR]

Abstract Background The emergence and spread of malaria parasites resistant to artemisinin-based combination therapy stresses the need for novel drugs against malaria. Investigating plants used in traditional medicine to treat malaria remains a credible option for new anti-malarial drug development. This study was aimed at investigating the antiplasmodial activity and selectivity of extracts and fractions from Terminalia mantaly and Terminalia superba (Combretaceae) that are used in Cameroon to treat malaria. Methods Twelve methanolic (m) and water (w) extracts obtained by maceration of powdered dried leaves (l), stem bark (sb) and root (r) of Terminalia mantaly (Tm) and Terminalia superba (Ts) and 12 derived fractions of hexane, chloroform, ethyl acetate and 4 final residues of selected extracts were assessed for antiplasmodial potential in vitro against the chloroquine-resistant PfINDO and the chloroquine-sensitive Pf3D7 strains of Plasmodium falciparum using the SYBR green I-based fluorescence assay. The cytotoxicity of potent extracts and fractions was evaluated in vitro using the MTT assay on HEK239T cell line. Results The antiplasmodial IC50 of extracts from both plants ranged from 0.26 to > 25 µg/mL. Apart from the extracts Tmrm and Tsrw that exerted moderate antiplasmodial activities (IC50: 5–20 µg/mL) and Tmrw that was found to be non-active at the tested concentrations (IC50 > 25 µg/mL), all other tested crude extracts exhibited potent activities with IC50 158) on both resistant PfINDO and sensitive Pf3D7 strains. Four fractions upon further extraction with chloroform and ethyl acetate (TmlwChl, TmsbwChl, TmsbwEA, TsrmEA) afforded from three selected crude extracts (Tmlw, Tmsbw, Tsrm) exhibited highly potent activities against both P. falciparum strains (IC50 109). Conclusions The results achieved in this work validate the reported traditional use of Terminalia mantaly and Terminalia superba to treat malaria. Moreover, the highly potent and selective fractions warrant further investigation to characterize the active antiplasmodial principles and progress them to rodent malaria models studies if activity and selectivity are evidenced.

Infrared (IR) imaging, chlorophyll fluorescence imaging and plant phenomic approach were used to study physiological mechanism of desiccation tolerance in Azadirachta indica and Terminalia mantaly during the period of November 2018 to February 2019. IR imaging instrument was installed in the field for monitoring the canopy temperature dynamics of different canopy level including stem region of the tree throughout the day. Maximum photochemical efficiency (Fv/Fm) was measured with chlorophyll fluorescence measuring system for sun exposed leaves of A. indica and T. mantaly over a period of desiccation. In order to reveal complete understanding of physiological mechanism of desiccation tolerance, plant phenomic approach was used for assessing response of these tree species to exposed desiccation. Results indicated that canopy temperature of upper foliage, lower foliage, stem (trunk) region of A. indica were quite higher during the hotter period of the day as compared to T. mantaly and maximum photochemical efficiency (Fv/Fm) was maintained in A. indica leaves as compared to T. mantaly for same exposed duration of desiccation. Plant phenomic approach also depicted that A. indica twig retained more tissue water and maintained canopy volume area higher than T. mantaly. Thus it provides an indication that A. indica tree is quite desiccation tolerant than T. mantaly by maintaining its canopy temperature, maximum photochemical efficiency, more tissue water and canopy area. [ABSTRACT FROM AUTHOR]

Scientists have demonstrated the potential of plant materials as ‘green’ reducing and stabilizing agents for the synthesis of gold nanoparticles (AuNPs) and opened new ecofriendly horizons to develop effective and less harmful treatment strategies. The current study demonstrated the use of Terminalia mantaly (TM) extracts to synthesize AuNPs with enhanced cytotoxic effects. The TM-AuNPs were synthesized at 25 and 70 °C using water (WTM) and methanolic (MTM) extracts of the leaf, root and stem/bark parts of the plant. The TM-AuNPs were characterized using UV–visible spectrophotometry, dynamic light scattering (DLS), transmission electron microscopy, energy dispersive X-ray (EDX), selection area electron diffraction (SAED) and Fourier transform infrared (FTIR) spectroscopy. Majority of the TM-AuNPs were spherical with a mean diameter between 22.5 and 43 nm and were also crystalline in nature. The cytotoxic effects of TM-AuNPs were investigated in cancer (Caco-2, MCF-7 and HepG2) and non-cancer (KMST-6) cell lines using the MTT assay. While the plant extracts showed some cytotoxicity towards the cancer cells, some of the TM-AuNPs were even more toxic to the cells. The IC50 values (concentrations of the AuNPs that inhibited 50% cell growth) as low as 0.18 µg/mL were found for TM-AuNPs synthesized using the root extract of the plant. Moreover, some of the TM-AuNPs demonstrated selective toxicity towards specific cancer cell types. The study demonstrates the potential of TM extracts to produce AuNPs and describe the optimal conditions for AuNPs using TM extracts. The toxicity of some the TM-AuNPs can possibly be explored in the future as an antitumor treatment.

Mycoses caused by Candida and Cryptococcus species, associated with the advent of antifungal drug resistance have emerged as major health problems. Improved control measures and innovative therapies are needed. This paper describes results from the screening of bio-guided fractionated extracts alone and combinations of Terminalia catappa, Terminalia mantaly and Monodora tenuifolia harvested in Cameroon. Crude ethanolic, hydro-ethanolic and aqueous extracts and bio-guided fractions were screened for antifungal activity against isolates of C. albicans, C. glabrata, C. parapsilosis and Cr. neoformans and the reference strain C. albicans NR-29450. Minimal inhibitory concentrations (MIC) were determined using a broth micro dilution method according to the Clinical & Laboratory Standards Institute (CLSI). Time kill kinetics of extracts alone and in combination were also evaluated. Extracts from T. mantaly stem bark were the most active with the best MIC values ranging from 0.04 mg/mL to 0.16 mg/mL. Synergistic interactions were observed with combinations of sub-fractions from M. tenuifolia, T. mantaly and T. catappa. Combination of sub-fractions from M. tenuifolia and T. mantaly (C36/C12) showed synergistic interaction and fungicidal effect against four out of five tested yeasts. These results support further investigation of medicinal plant extracts alone and in combination as starting points for the development of alternative antifungal therapy.

Cananga odorata (Annonaceae), Terminalia catappa and Terminalia mantaly (Combretaceae) are medicinal plants used in Cameroon to treat several diseases. In this study endophytic fungi associated with these plants were isolated and identified, and their enzymatic activities were determined. For this purpose, endophytes isolated from samples of leaves, stems, bark, roots, and flowers of each species were classified according to culture morphology and nucleotide sequences of internal transcribed spacer (ITS) regions of ribosomal genes. With this technique, the isolates were classified into 21 genera of ascomycetes. The fungal collection was further characterized on the basis of amylase, cellulose, lipase, and laccase enzymatic activity. Isolates positive for all or some of these activities were detected. The results indicate that these medicinal plants contain a high diversity of endophytic fungi, and could be a repository of valuable bioactive chemicals. In addition, this study showed that these fungi could be useful for the production of enzymes of industrial importance. [ABSTRACT FROM AUTHOR]

Background: Pathogenic yeasts resistance to current drugs emphasizes the need for new, safe, and cost-effective drugs. Also, new inhibitors are needed to control the effects of enzymes that are implicated in metabolic dysfunctions such as cancer, obesity, and epilepsy. Methods: The anti-yeast extract from Terminalia mantaly (Combretaceae) was fractionated and the structures of the isolated compounds established by means of spectroscopic analysis and comparison with literature data. Activity was assessed against Candida albicans, C. parapsilosis and C. krusei using the microdilution method, and against four enzymes of metabolic significance: glucose-6-phosphate dehydrogenase, human erythrocyte carbonic anhydrase I and II, and glutathione S-transferase. Results: Seven compounds, 3,3′-di-O-methylellagic acid 4′-O-α-rhamnopyranoside; 3-O-methylellagic acid; arjungenin or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid; arjunglucoside or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid glucopyranoside; 2α,3α,24-trihydroxyolean-11,13(18)-dien-28-oïc acid; stigmasterol; and stigmasterol 3-O-β-d-glucopyranoside were isolated from the extract. Among those, 3,3′-di-O-methylellagic acid 4′-O-α-rhamnopyranoside, 3-O-methylellagic acid, and arjunglucoside showed anti-yeast activity comparable to that of reference fluconazole with minimal inhibitory concentrations (MIC) below 32 µg/mL. Besides, Arjunglucoside potently inhibited the tested enzymes with 50% inhibitory concentrations (IC50) below 4 µM and inhibitory constant (Ki)

Terminalia mantaly (H. Perrier) and Terminalia superba (Engl. & Diels) are sources of treatment for various diseases, including malaria and/or related symptoms in parts of Southwestern Cameroon. However, there is limited information on the extent of the antiplasmodial potential of their extracts. The present study was designed to investigate the antiplasmodial potential of chromatographic sub fractions (SFs) from promising fractions of Terminalia mantaly (Tm) [ Tm sbwChl, the chloroform fraction from water extract of Tm , IC 50 (μg/mL) Pf INDO: 0.56, Pf 3D7: 1.12; SI > 357 (HEK/ Pf INDO) & 178 (HEK/ Pf 3D7)] and Terminalia superba (Ts) [ Ts rmEA, the ethyl acetate fraction from methanolic extract of Ts , IC 50 (μg/mL) Pf INDO: 1.82, Pf 3D7: 1.65; SI > 109 (HEK/ Pf INDO) & 121 (HEK/ Pf 3D7)] obtained from previous studies. The SFs were tested against Plasmodium falciparum 3D7 (Pf 3D7-chloroquine sensitive) and INDO (Pf INDO-chloroquine resistant) strains in culture. Also, the phytochemical profile of potent SFs was determined and finally, the inhibition of the asexual blood stages of Plasmodium falciparum by the SFs with the highest promise was assessed. Selected SFs were submitted to a second bio-guided fractionation using silica gel column chromatography. The partial phytochemical composition of potent antiplasmodial SFs was determined using gas chromatography coupled to mass spectrometry (GC–MS). The SYBR Green I-based fluorescence microtiter plate assay was used to monitor the growth of Plasmodium falciparum parasites in culture in the presence or absence of extracts. Microscopy and flow cytometry counting was used to assess the Plasmodium falciparum stage–specific inhibition and post–drug exposure growth suppression by highly potent extracts. Twenty-one of the 39 SFs afforded from Tm sbwChl showed activity (IC 50 : 0.29–4.74 μg/mL) against both Pf 3D7 and Pf INDO strains. Of note, eight SFs namely, Tm 25, Tm 28-30, Tm 34-36 and Tm 38, exerted highly potent antiplasmodial activity (IC 50 < 1 μg/mL) with IC 50 Pf INDO: 0.41–0.84 μg/mL and IC 50 Pf 3D7: 0.29–0.68 μg/mL. They also displayed very high selectivity (50 < SI Pf INDO , SI Pf 3D7 > 344) on the two Plasmodial strains. On the other hand, 7 SFs (SFs Ts 03, Ts 04, Ts 06, Ts 09, Ts 10, Ts 12 and Ts 13) from Ts rmEA showed promising inhibitory potential against both parasite strains (IC 50 : 2.01–5.14 μg/mL). Sub fraction Tm 36 (IC 50 Pf INDO: 0.41 μg/mL, SI Pf INDO > 243; IC 50 Pf 3D7: 0.29 μg/mL, SI Pf 3D7 > 344) showed the highest promise. The GC–MS analysis of the 8 selected SFs led to the identification of 99 phytometabolites, with D-limonene (2), benzaldehyde (12), carvone (13), caryophyllene (35), hexadecanoic acid, methyl ester (74) and 9-octadecenoic acid, methyl ester (82) being the main constituents. Sub fractions Tm 28, Tm 29 , Tm 30 , Tm 36 and Tm 38 inhibited all the three intraerythrocytic stages of P. falciparum , with strong potency against ring stage development, merozoite egress and invasion processes. This study has identified highly potent antiplasmodial SFs from Terminalia mantaly with significant activity on the intraerythrocytic development of Plasmodium falciparum. These SFs qualify as promising sources of novel antiplasmodial lead compounds. Further purification and characterization studies are expected to unravel molecular targets in rings and merozoites. [Display omitted] • Subfractions from Terminalia mantaly showed highly potent (IC 50 s < 1 μg/mL) anti-plasmodial activity. • GC–MS chemical profiling identified over hundred different phytocompounds in promising subfractions. • Active subfractions inhibited all intraerythrocytic stages of Plasmodium falciparum. • Highly potent subfractions selectively hindered ring and merozoites stages progress. [ABSTRACT FROM AUTHOR]

Scientists have demonstrated the potential of plant materials as 'green' reducing and stabilizing agents for the synthesis of gold nanoparticles (AuNPs) and opened new ecofriendly horizons to develop effective and less harmful treatment strategies. The current study demonstrated the use of Terminalia mantaly (TM) extracts to synthesize AuNPs with enhanced cytotoxic effects. The TM-AuNPs were synthesized at 25 and 70 °C using water (WTM) and methanolic (MTM) extracts of the leaf, root and stem/bark parts of the plant. The TM-AuNPs were characterized using UV–visible spectrophotometry, dynamic light scattering (DLS), transmission electron microscopy, energy dispersive X-ray (EDX), selection area electron diffraction (SAED) and Fourier transform infrared (FTIR) spectroscopy. Majority of the TM-AuNPs were spherical with a mean diameter between 22.5 and 43 nm and were also crystalline in nature. The cytotoxic effects of TM-AuNPs were investigated in cancer (Caco-2, MCF-7 and HepG2) and non-cancer (KMST-6) cell lines using the MTT assay. While the plant extracts showed some cytotoxicity towards the cancer cells, some of the TM-AuNPs were even more toxic to the cells. The IC50 values (concentrations of the AuNPs that inhibited 50% cell growth) as low as 0.18 µg/mL were found for TM-AuNPs synthesized using the root extract of the plant. Moreover, some of the TM-AuNPs demonstrated selective toxicity towards specific cancer cell types. The study demonstrates the potential of TM extracts to produce AuNPs and describe the optimal conditions for AuNPs using TM extracts. The toxicity of some the TM-AuNPs can possibly be explored in the future as an antitumor treatment. [ABSTRACT FROM AUTHOR]

Background: The emergence and spread of malaria parasites resistant to artemisinin-based combination therapy stresses the need for novel drugs against malaria. Investigating plants used in traditional medicine to treat malaria remains a credible option for new anti-malarial drug development. This study was aimed at investigating the antiplasmodial activity and selectivity of extracts and fractions from Terminalia mantaly and Terminalia superba (Combretaceae) that are used in Cameroon to treat malaria. Methods: Twelve methanolic (m) and water (w) extracts obtained by maceration of powdered dried leaves (l), stem bark (sb) and root (r) of Terminalia mantaly (Tm) and Terminalia superba (Ts) and 12 derived fractions of hexane, chloroform, ethyl acetate and 4 final residues of selected extracts were assessed for antiplasmodial potential in vitro against the chloroquine-resistant PfINDO and the chloroquine-sensitive Pf3D7 strains of Plasmodium falciparum using the SYBR green I-based fluorescence assay. The cytotoxicity of potent extracts and fractions was evaluated in vitro using the MTT assay on HEK239T cell line. Results: The antiplasmodial IC50 of extracts from both plants ranged from 0.26 to > 25 µg/mL. Apart from the extracts Tmrm and Tsrw that exerted moderate antiplasmodial activities (IC50: 5–20 µg/mL) and Tmrw that was found to be non-active at the tested concentrations (IC50 > 25 µg/mL), all other tested crude extracts exhibited potent activities with IC50 < 5 µg/mL. The aqueous extracts from the stem bark of Terminalia mantaly (Tmsbw) and the leaf of Terminalia superba (Tslw) displayed the highest antiplasmodial activities (IC50: 0.26–1.26 µg/mL) and selectivity (SI > 158) on both resistant PfINDO and sensitive Pf3D7 strains. Four fractions upon further extraction with chloroform and ethyl acetate (TmlwChl, TmsbwChl, TmsbwEA, TsrmEA) afforded from three selected crude extracts (Tmlw, Tmsbw, Tsrm) exhibited highly potent activities against both P. falciparum strains (IC50 < 2 µg/mL) and high selectivity (SI > 109). Conclusions: The results achieved in this work validate the reported traditional use of Terminalia mantaly and Terminalia superba to treat malaria. Moreover, the highly potent and selective fractions warrant further investigation to characterize the active antiplasmodial principles and progress them to rodent malaria models studies if activity and selectivity are evidenced. [ABSTRACT FROM AUTHOR]

Background : Pathogenic yeasts resistance to current drugs emphasizes the need for new, safe, and cost-effective drugs. Also, new inhibitors are needed to control the effects of enzymes that are implicated in metabolic dysfunctions such as cancer, obesity, and epilepsy. Methods: The anti-yeast extract from Terminalia mantaly (Combretaceae) was fractionated and the structures of the isolated compounds established by means of spectroscopic analysis and comparison with literature data. Activity was assessed against Candida albicans , C. parapsilosis and C. krusei using the microdilution method, and against four enzymes of metabolic significance: glucose-6-phosphate dehydrogenase, human erythrocyte carbonic anhydrase I and II, and glutathione S -transferase. Results: Seven compounds, 3,3'-di- O -methylellagic acid 4'- O -α-rhamnopyranoside; 3- O -methylellagic acid; arjungenin or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid; arjunglucoside or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid glucopyranoside; 2α,3α,24-trihydroxyolean-11,13(18)-dien-28-oïc acid; stigmasterol; and stigmasterol 3- O -β-d-glucopyranoside were isolated from the extract. Among those, 3,3'-di- O -methylellagic acid 4'- O -α-rhamnopyranoside, 3- O -methylellagic acid, and arjunglucoside showed anti-yeast activity comparable to that of reference fluconazole with minimal inhibitory concentrations (MIC) below 32 µg/mL. Besides, Arjunglucoside potently inhibited the tested enzymes with 50% inhibitory concentrations (IC 50 ) below 4 µM and inhibitory constant (Ki) <3 µM. Conclusions: The results achieved indicate that further SAR studies will likely identify potent hit derivatives that should subsequently enter the drug development pipeline.

Mycoses caused by Candida and Cryptococcus species, associated with the advent of antifungal drug resistance have emerged as major health problems. Improved control measures and innovative therapies are needed. This paper describes results from the screening of bio-guided fractionated extracts alone and combinations of Terminalia catappa, Terminalia mantaly and Monodora tenuifolia harvested in Cameroon. Crude ethanolic, hydro-ethanolic and aqueous extracts and bio-guided fractions were screened for antifungal activity against isolates of C. albicans , C. glabrata , C. parapsilosis and Cr. neoformans and the reference strain C. albicans NR-29450. Minimal inhibitory concentrations (MIC) were determined using a broth micro dilution method according to the Clinical & Laboratory Standards Institute (CLSI). Time kill kinetics of extracts alone and in combination were also evaluated. Extracts from T. mantaly stem bark were the most active with the best MIC values ranging from 0.04 mg/mL to 0.16 mg/mL. Synergistic interactions were observed with combinations of sub-fractions from M. tenuifolia , T. mantaly and T. catappa. Combination of sub-fractions from M. tenuifolia and T. mantaly (C36/C12) showed synergistic interaction and fungicidal effect against four out of five tested yeasts. These results support further investigation of medicinal plant extracts alone and in combination as starting points for the development of alternative antifungal therapy.