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Aims: Schumanniophyton magnificum is a plant reputed traditionally to treat numerous urogenital infections linked to several germs, notably: Escherichia coli, Staphylococcus aureus, Neisseria gonhorhea, Treponema palidum, Candida albican. This study aims to evaluate and compare the in vitro antibacterial and cytotoxic activities of the leaves, trunk and roots of S. magnificum in order to determine the parts displaying the best activity. Study Design: This is an experimental study. Location and Duration of the Study: The work was conducted at the Pharmacochemistry and Natural Substances Laboratories of the Faculty of Medicine and Pharmaceutical Sciences, University of Douala for the extraction and at the Medical Analysis Laboratory of the Douala General Hospital for antibacterial test as well as Biomedical Chemistry Research Center of Rhodes University in South Africa for cytotoxic essay. All the experiments were carried out from the 15th November 2020 to the 31th May 2021. Methodology: The in vitro Antibacterial activity essay was conducted on two strains, one Gram+ bacteria: Staphylococcus aureus and one Gram- bacteria: Escherichia coli, while cytotoxicity was evaluated on HeLa cell line. Results: The root wood extract and the root bark extract presented a good antibacterial activity (MIC = 195.31 µg/mL) and average activity (MIC = 390.63 µg/mL) respectively with E. coli. The different extracts were found to be bactericidal against the tested micro-organisms. At the concentration of 20 µg/mL, all extracts tested did not significantly reduce HeLa cells, with an inhibition rate ranging from 13.5 to 37.6%, suggesting a low cytotoxicity of S. magnificum extracts towards these human cells line. Conclusion: This is the first comparative report on the antibacterial and cytotoxic study conducted on the different parts of S. magnificum. It appears from this study that these results could justify the use of the stem bark of S. magnificum in the traditional pharmacopeia for the treatment of urogenital infections. However, the roots wood having presented the best antibacterial activity (MIC = 195.31 µg/mL), it would be beneficial to suggest this plant part to the local populations for the treatment of bacterial diseases specific to E. coli and S. aureus, after the preclinical and clinical tests are carried out.

Background: Despite the various medicinal applications of Schumanniophyton magnificum, no comparative data are available to determine the part with best antiplasmodial activity and to guarantee its safety. This work deals with the evaluation of the antiplasmodial activity of methanolic extracts of S. magnificum organs as well as the study of acute toxicity of the most active part. Materials and methods: The methanolic extracts of the leaves, stem bark, trunk wood, root wood and root bark, were obtained by maceration with 96% methanol. Phytochemical screening, based on precipitation and coloring reactions, to highlight the chemical groups present in the plant. The antiplasmodial test was ran against chloroquine sensitive Plasmodium falciparum 3D7 strains while the study of the in vivo acute toxicity was conducted according to guideline 423 of the OECD protocol at a fixed dose on Wistar rats. Results: Phytochemical screening of the methanol extracts of these plants organs revealed the presence of alkaloids, triterpenoids, saponins, anthraquinones, polyphenols, coumarins anthocyanins and flavonoids. The antiplasmodial activity showed that only the leaves exhibited a moderate antiplasmodial effect with IC50 of 30.77 µg/ml. An oral administration of the methanolic extract of the leaves did not induce an abnormal variation of the physiological parameters in female Wistar laboratory rats, at non-toxic doses of 50, 300 and 2000 mg/kg body weight for 14 days. Conclusion: The leaves of S. magnificum exhibited the best antimalarial activity and were non toxic, thus justifying the use of the plant in the treatment of malaria in traditional pharmacopoeia. Keywords: Phytochemical screening, Antiplasmodial activity, Acute toxicity, Schumanniophyton magnificum, Medicinal plant.

Aims: This study aimed to evaluate and compare the in vitro anti-plasmodial and cytotoxic effect of the methanolic extracts from leaves, stem bark and roots of Annickia affinis. Study Design: This is an experimental study. Place and Duration of Study: The work was conducted at the Pharmacochemistry and Natural Substances Laboratories of the Faculty of Medicine and Pharmaceutical Sciences, University of Douala for the extraction and at the Biomedical Chemistry Research Center of Rhodes University in South Africa for the antimalarial and cytotoxic essay. All the experiments were carried out from the 15th October 2019 to the 31th July 2020. Methodology: The anti-plasmodial test was performed on Plasmodium falciparum sensitive strains 3D7 while cytotoxicity was evaluated on the HeLa cell line. Results: The anti-plasmodial tests revealed that the roots and the stem bark exhibited a moderate anti-plasmodial effect with IC50 of 19.7 ± 0.8 and 12.1 ± 0.8 µg/ml respectively. The anti-plasmodial effects of the leaves were classified as low (33.7 ± 1.9 µg/ml). At up to 50 µg/ml, all the extracts showed a high rate of survival among the HeLa cells. No effect was observed with the leaf extracts (100% of survival). Conclusion: This is the first report on the cytotoxic study and comparative anti-plasmodial effect of Annikia affinis. It highlights the potential of Annickia affinis as an important source of anti-plasmodial drugs with less cytotoxic in vitro. In agreement with the use in traditional medicine, the stem bark was more active than wood, while leaves showed low activity.

Background: Ficus elastica is a plant used in traditional medicine for the treatment of allergies and skin infections. This study aimed to investigate the antimicrobial, antiplasmodial, and antiproliferative activities of the crude extract and fraction of F. elatica as well as the study of the in vivo oral acute toxicity of the most active fraction. Methods: The antimicrobial activity of the total extract and the different fractions was evaluated by the determination of the inhibition diameter using the agar well diffusion method on 3 Gram (+) bacteria, 4 Gram (-) bacteria, and 2 fungi, by the determination of MIC using the micro-dilution method only on the strains that showed sensitivity on the agar and by the determination of MMC on Muller Hinton agar. The evaluation of antimalarial activity was done on Plasmodium falciparum 3D7 cells by measuring the parasite lactate dehydrogenase (pLDH) activity using the mixture of Malstat and NBS/PES. Extracts were afterward evaluated for their antiproliferative effect on 2 human cell lines (human oligodendroglioma and breast cancer) and mouse melanoma using colorimetric MTT assay. The toxicity assessment of the most active fraction was performed in vivo according to the modified OECD 425 guidelines. Results: Total extract and different fractions were not active on different strains because the MICs values are > 1024 µg/mL. Dichloromethane and hexane fractions were bactericidal with a ratio CMM/CMI of 2 and the total extract would be bacteriostatic. The antimalarial activity showed that the hexane fraction reduced the viability of P. falciparum 3D7 cells by 61.4% with an IC50 value of 26.41 µg/mL. As for the antiproliferative activity, the dichloromethane fraction significantly inhibited different cell lines with IC50 values between 13 and 16.5 µg/mL. The toxicity study conducted on the hexane fraction, being the most active fraction, resulted in no apparent signs of toxicity and no death at doses of 2000 mg/kg bw and 5000 mg/kg bw over a period of 14 days. Conclusion: Methanolic crude extract of F. elastica lianas and its hexane as well as dichloromethane fractions possess low antibacterial activity. The dichloromethane fraction possesses antiproliferative activity while the hexane fraction possesses antiplasmodial activity and presented no signs of acute toxicity by the oral route. These results support the use of F. elastica in the treatment of several ailments such as skin infections.

Aims: This study aims to evaluate the in vivo acute and sub-acute toxicity; and the antimicrobial activity of Anonidium mannii stem bark ethanolic extract. Study Design: This is an experimental study. Location and Duration of the Study: The work was conducted from 15 November 2020 to 31 May 2021 at several laboratories (the Faculty of Medicine and Pharmaceutical Sciences Laboratory of the University of Douala, the Animal Physiology Laboratory of the Faculty of Medicine and Biomedical Sciences at the University of Yaoundé 1 and in the Hematology and Bacteriology Laboratories of the District Hospital of the Cité des Palmiers, Douala, Cameroon). Methodology: The in vivo acute and subacute toxicities studies were conducted following the guidelines of the OECD on Wistar rats, while the in vitro antimicrobial activity was evaluated using the microdilution method on bacterial (Neisseria gonorrheae, Escherichia coli, Salmonela spp) and fungal (Candida albicans) strains. Results: Phytochemical screening revealed the presence of alkaloids, anthraquinones, coumarins, flavonoids, phenols, reducing sugars, tannins, triterpenes. An oral administration of the extract did not induce an abnormal variation of the physiological parameters in rats, at doses of 2000 and 5000 mg/kg body weight for 14 days. After twenty-eight days of observation during the study of subacute toxicity, the extract showed good safety in terms of subacute toxicity. No deaths were recorded at the different doses; and clinical and physiological parameters analyses revealed a non-significant statistical difference. All bacterial strains in the presence of the extract were inhibited, as well as C. albicans. The extract exhibited strong antibacterial activity against N. gonorheae (MIC 15.6 μg/mL), E. coli (MIC 62.5 μg/mL) and Salmonella spp (MIC 15.6 μg/mL). Conclusion: These results could justify the use of A. mannii stem bark in the traditional pharmacopoeia for the treatment of gonococcal disease, diarrhea, abscesses and food poisoning.

Aims: This study aimed at identifying the phytochemical constituents, to evaluate and compare the in vitro antioxidant potential of the methanolic extracts of the leaves, trunk (wood and bark) and roots (wood and bark) of Anonidium mannii (Oliv) Engl. and Diels which is used in Cameroon for the treatment of rheumatism. Place and Duration of Study: The work was conducted at the Pharmacochemistry and Natural Substances Laboratories of the Faculty of Medicine and Pharmaceutical Sciences, University of Douala. All the experiments were carried out from the 15th October 2019 to the 31th July 2020. Methodology: Phytochemical screening was based on conventional techniques focusing on color reactions and precipitation. The evaluation of the antioxidant power was carried out by the method of scavenging the free radical DPPH of the extracts and by reading the absorbance for each concentration at 517 nm. Results: The phytochemical screening of the extracts revealed the presence of alkaloïds, flavonoïds, anthraquinones, coumarins, terpenes, steroïds, saponins, phenols and anthocyanins. All extracts tested showed antioxidant activity, particularly root wood with an IC50 = 1.85 µg/ml identical to the standard (BHT: Butylhydroxytoluène). Conclusion: Due to evidence that reactive oxygen species play a causal role in auto-immune diseases, such as rheumatoid arthritis, these results justify the use of the leaves or the stem bark of A. mannii in the traditional pharmacopeia for the treatment of rheumatism. However, the wood of the roots having presented the best activity (IC50 = 1.85 µg/ml). It would be beneficial to suggest this plant part to the local populations for the management of that pathology. This study is the first comparative biological study conducted on the different parts of A. mannii.

This study aimed to determine the phytochemical profile, acute toxicity, and antioxidant activity of leaves, stem bark, and roots of methanolic extracts of Annickia affinis. Phytochemical screening was done to highlight the secondary metabolites present in the plant. The in vitro antioxidant activity was carried out using the DPPH free radical trapping method based on our extracts' reduction of the DPPH radical. This was evaluated by measuring the absorbance of all concentrations of extracts tested at 517 nm. Whereas the total phenol content was quantified using the reagent of “Folin-Ciocalteu,” measurable using a spectrophotometer at 765 nm. The in vivo acute toxicity study was conducted according to guideline 423 of the Organisation for Economic Co-operation and Development (OECD) protocol at a fixed dose in Wistar rats. Phytochemical screening of the different extracts revealed the presence of alkaloids, saponins, triterpenoids, anthraquinones, anthocyanins, and coumarins. The extracts of the leaves, stem bark, and roots showed good DPPH radical scavenging activity with IC50 values of 0.34 µg/mL, 0.37 µg/mL, and 0.22 µg/mL, respectively; these values were very close to that recorded for the standard, Butyl hydroxytoluène (BHT) (0.14 µg/mL). The total phenolic contents were 122.11 µgEqGA/g for the leaves, 47.11 µgEqGA/g for the stem bark, and 109.95 µgEqGA/g for the roots. An oral administration of all extracts did not cause an abnormal variation of the physiological parameters in female Wistar laboratory rats at doses of 2000 and 5000 mg/kg body weight up to 14 days after administration. The methanolic extracts of the leaves, stem bark, and roots of A. affinis are thus non-toxic at a dose as high as 5000 mg/kg body weight. They all have good antioxidant activity, the best activity recorded for the roots. It would be beneficial to suggest A. affinis to local populations against pathologies linked to oxidative stress after the preclinical and clinical tests.

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 us...

Ethnopharmacological relevance: The dicotyledonous plant Piptadeniastrum africanum (hook.f.) Brennan (Fabaceae) is used in traditional medicine to treat various human complaints including bronchitis, coughing, urino-genital ailments, meningitis, abdominal pain, treatment of wounds, malaria and gastrointestinal ailments, and is used as a purgative and worm expeller. Aim of the study: The present study describes the phytochemical investigation and the determination of the antimicrobial, antiplasmodial and antitrypanosomal activities of crude extract, fractions and compounds extracted from Piptadeniastrum africanum roots. Materials and methods: Isolated compounds were obtained using several chromatographic techniques. The structures of all compounds were determined by comprehensive spectroscopic analyses (1D and 2D NMR) and by comparing their NMR data with those found in literature. In vitro antimicrobial activity of samples was evaluated using the microdilution method on bacterial (Escherichia coli, Proteus mirabilis, Staphylococcus aureus) and fungal (Candida krusei) strains, while in vitro cell-growth inhibition activities were assessed against two parasites (Trypanosoma brucei brucei and Plasmodium falciparum strain 3D7). The cytotoxicity properties of samples were assayed against HeLa human cervical carcinoma. Results: Five compounds were isolated and identified as: tricosanol 1, 5α-stigmasta-7,22-dien-3-β-ol 2, betulinic acid 3, oleanolic acid 4 and piptadenamide 5. This is the first report of the isolation of these five compounds from the roots of P. africanum. The (Hex:EtOAc 50:50) fraction exhibited moderate antibacterial activity against P. mirabilis (MIC 250 μg/mL), while the other fractions and isolated compounds had weak antimicrobial activities. Only the EtOAc fraction presented a moderate antimalarial activity with an IC50 of 16.5 μg/mL. The MeOH crude extract and three fractions (Hexane, Hexane-EtOAc 25% and EtOAc-MeOH 25%) exhibited significant trypanocidal activity with IC50 values of 3.0, 37.5, 3.8 and 9.5 μg/mL, respectively. Conclusion: These results demonstrated a scientific rational of the traditional uses of P. africanum and indicate that this plant should be further investigated to identify some of the chemical components that exhibited the activities reported in this study and therefore may constitute new lead candidates in parasiticidal drug discovery., SCOPUS: ar.j, info:eu-repo/semantics/published

Phytochemical investigation of the methanol extracts of the twigs of Manniophyton fulvum has led to the isolation and characterization of three new pentacyclic triterpenoids, designated as 3α,28-dihydroxyfriedelan-1-one (1), manniotaraxerol A (3) and manniotaraxerol B (4), along with fourteen known compounds, 3α-hydroxy-1-oxofriedelane (2), betulinic acid (5), friedelin (S1), taraxerol (S2), a mixture of stigmasterol (S3) and β-sitosterol (S4), herranone (S5), docosanoic acid (S6), ursolic acid (S7), nasutin B (S8), bergenin (S9), stigmasterol-3-O-β- d- glucopyranoside (S10), 1,2-di-O-palmitoyl-3-O-(6-sulfo-α- d -quinovopyranosyl)glycerol (S11), and aridanin (S12). The structures of all compounds were determined by comprehensive spectroscopic analyses (1D and 2D NMR, EI and ESI-MS). 3α,28-Dihydroxyfriedelan-1-one (1), 3α-hydroxy-1-oxofriedelane (2), manniotaraxerol A (3), manniotaraxerol B (4), and betulinic acid (5) were evaluated against HeLa (human cervix adenocarcinoma) cancer cells. Manniotaraxerol A (3) showed weak in vitro cytotoxicity with a cell viability value of 49.3%. Betulinic acid (5) also showed significant cytotoxicity against HeLa cell with a cell viability value of 4.0%; the other compounds were inactive in this test.

The natural products from plants still remain an important source of pharmaceuticals. In the current study, methanolic wood extracts of Ficus elastica Roxb. ex Hornem. (Moraceae) aerial roots were screened for anti-cancer activity. Using bioassay-guided fractionation, three new compounds, elasticamide ( 1 ), elastiquinone ( 2 ) and ficusoside B ( 3 ), together with four known compounds, were isolated. The structures of the new compounds were established by means of extensive spectroscopic analyses (1D and 2D NMR, HR-ESI-MS, as well as IR and UV) and by comparison of their spectroscopic data with those reported for structurally related molecules. The isolated compounds were afterwards evaluated for their anti-proliferative effect on six human cancer cell lines (U373n and Hs683 glioblastoma, MCF7 and A549 NSCLC carcinoma, and B16F10 and SK-MEL-28 melanoma) using colorimetric MTT assay. Most notably, elastiquinone ( 2 ) showed cytotoxic activity with IC 50 = 14 μM against B16F10 melanoma cells, whereas the peracetylated form of ficusoside B ( 3a ) displayed the lowest IC 50 value (11 μM) against U373n glioma cell lines. Elasticamide ( 1) and ficusoside B ( 3) exhibited a weak cytotoxicity with IC 50 values ≥ 88 μM. The results of this investigation demonstrate that the wood of F. elastica aerial roots might be a potential source for identifying new compounds with potent anti-proliferative activity.

African medicinal plants represent a prominent source of new active substances. In this context, three plants were selected for biological investigations based on their traditional uses.The antimicrobial and anti-proliferative features of three plants used for medicinal purpose were evaluated.The antimicrobial activities of methanol extracts of Ficus bubu Warb. (Moraceae) stem bark and leaves, of Spathodea campanulata P. Beauv. (Bignoniaceae) flowers, as well as those of Carica papaya Linn. (Caricaceae) latex, were determined using the microbroth dilution method against a set of bacteria and fungi pathogens including: Enterococcus faecalis, Staphylococcus aureus, S. saprophyticus, S. epidermididis, Escherichia coli, Klebsiella pneumonia, Salmonella typhimurium, Candida albicans, and Trichophyton rubrum. The tested concentrations of extracts ranged from 2500.0 to 2.4 μg/mL and MIC values were evaluated after 24 h incubation at 37 °C. Subsequently, MTT assay was used to estimate anti-proliferative activity of these methanol extracts and of F. bubu latex on three human cancer cell lines (U373 glioblastoma, A549 NSCLC, and SKMEL-28 melanoma).The methanol extract of F. bubu stem bark exhibited the highest antimicrobial activity against C. albicans with a MIC value of 9.8 μg/mL, while the F. bubu latex and the methanol extract of F. bubu leaves induced significant anti-proliferative activity against lung (IC50 values of 10 and 14 μg/mL, respectively) and glioma (IC50 values of 13 and 16 μg/mL, respectively) cancer cells.These results indicate that effective drugs could be derived from the three studied plants.

The cytotoxic, antiplasmodial, and antitrypanosomal activities of two medicinal plants traditionally used in Cameroon were evaluated. Wood of Ficus elastica Roxb. ex Hornem. aerial roots (Moraceae) and Selaginella vogelii Spring (Selaginellaceae) leaves were collected from two different sites in Cameroon. In vitro cell-growth inhibition activities were assessed on methanol extract of plant materials against Plasmodium falciparum strain 3D7 and Trypanosoma brucei brucei, as well as against HeLa human cervical carcinoma cells. Criteria for activity were an IC50 value, SCOPUS: ar.j, info:eu-repo/semantics/published

Phytochemical investigation of the roots of Cola rostrata K. Schum. led to the isolation of a new unsaturated fatty acid, named rostratanic acid (1), together with fourteen known compounds, lignoceric acid, friedelan (7), friedelanone (8), bauerenol (3), lupeol (4), herranone (9), acotatarone A (11), betulinic acid (6), betulin (5), nonanedioc acid (2), arjunolic acid (10) stigmasterol, β−sitosterol, and β−sitosterol-3-O-β-D-glucopyranoside. The structure of the new compound as well as those of the known compounds were established by means of spectroscopic methods: NMR analysis (1H and 13C NMR, 1H–1H–COSY, HSQC and HMBC) and high-resolution mass spectrometry (HR-ESI-MS), and by comparison with previously reported data. Two of those known compounds were modified chemically to afford three new derivatives. All those compounds were tested for their cytotoxic activity against the human cervix carcinoma KB-3-1 cells and their antibacterial activity against Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and Staphylococcus aureus. Although the crude extract gave weak antibacterial activity, none of the isolated compounds showed antibacterial activity, and, only the prenylated derivative showed weak cytotoxicity. In addition, the chemotaxonomic significance of the species Cola rostrata is discussed.

Background : Plasmodium falciparum , one of the causative agents of malaria, has high adaptability through mutation and is resistant to many types of anti-malarial drugs. This study presents an in vitro assessment of the antiplasmodial activity of some phenolic compounds isolated from plants of the genus Allanblackia. Methods : Tests were performed on well plates filled with a fixed parasitized erythrocytes volume. Compounds to be tested were then added in wells. After incubation, tritiated hypoxanthine is added and the plates were returned to the incubator. After thawing, the nucleic acids are collected. Inhibitory Concentration 50 (IC50) was determined by linear interpolation. Results : From Allanblackia floribunda , have been isolated and characterized 1,7 -dihydroxyxanthone 1, macluraxanthone 4, morelloflavone 9, Volkensiflavone 10 and morelloflavone 7-O-glucoside 11; from Allanblackia monticola, α-mangosine 2, rubraxanthone 3, allaxanthone C 5, norcowanine 6 , tovophiline A 7, allaxanthone B 8 and from Allanblackia gabonensis, 1,7-dihydroxyxanthone 1. Six of them were evaluated for their antimalarial properties. The most active compound, macluraxanthone, presented a very interesting activity, with an IC50 of 0.36 and 0.27 μg/mL with the F32 and FcM29 strains respectively. Conclusion: This work confirms that species of Allanblackia genus are medicinally important plants containing many biologically active compounds that can be used effectively as antiplasmodial. Key words : Guttiferaceae, Allanblackia, Phenolic compounds, Antiplasmodial activity