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The increase in the development of multi-drug resistance among pathogens calls for the development of novel therapeutic agents with better effectiveness and low toxicity. The plantassociated endophytic fungi are producers of bioactive secondary metabolites with enormous potential. The study aimed to isolate, identify, and characterize the secondary metabolites of endophytic fungi isolated from different non-diseased plant parts (leaf, stem, and root bark) of Synclisia. scabrida Miers. The isolation of endophytic fungi was carried out using standard protocols and identified by molecular techniques. The bioactive secondary metabolites were extracted using ethyl acetate. The quantitative phytochemical screening of the fungal metabolites was carried out using Gas chromatography. The antimicrobial activities of ethyl acetate extracts of the isolates were analyzed via agar well diffusion technique and the minimum inhibitory concentrations (MICs) were determined by broth dilution method. The different endophytic fungal metabolites exhibited a good presence of different phytochemical compounds. The fungal metabolites showed antimicrobial activities against several of the six tested human pathogenic bacteria or fungi. Among these metabolites, L1, R1 and R2 metabolites were the most potent, exhibiting significant activities against the test organisms. L1 and R1 metabolites showed the lowest MIC of 0.53±0.13 and 0.70±0.07 mg/ml against A. niger and C. albicans respectively. A total of five endophytic fungi were isolated from the leaf, stem, and root bark of S. scabrida Miers, and three different fungal species were identified using molecular techniques. The plant, S. scabrida Miers harbors endophytic fungi yielding bioactive metabolites with potent antimicrobial activities against pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Medicinal plants are known for a number of health benefits. This study investigated the in-vitro antimicrobial activities and in-vivo malaria parasite clearance rate using respectively the methanol and aqueous extracts of Carica papaya seeds. Soxhlet and Cold-maceration extraction techniques were used to obtain the methanol and aqueous extracts, respectively. The phytochemical constituents were quantitatively/qualitatively analyzed. The antimicrobial activities of the extracts were tested Escherichia coli, Salmonella typhi, Staphylococcus aureus, and Pseudomonas aeruginosa using the agar-well-diffusion method. The minimum inhibitory concentration (MIC) of the extracts were determined using the agar-dilution method. Five groups of animals (mice) were used in this study, each having five animals each. The animals in group two to five were induced with Plasmodium berghei after which, those in group two, four, and five were treated with 25 mg/kg bw of artemether/lumefantrine and 200 and 400mg/kg bw of the plant aqueous extract respectively. Group three were not treated, while group one was neither induced nor treated. The phytochemical analysis showed presence/quantities of steroids, saponins, tannins, flavonoids, terpenoids, glycosides, reducing sugars, proteins, phenolic compounds, and alkaloids. With varying preliminary antimicrobial effects, the MIC of the methanol extract against E. coli and S. typhi were 62.5mg/ml and 125 mg/ml, respectively. The aqueous extract showed MIC of 125mg/ml against S. aureus. The antimalarial activity of aqueous extract increased in a dose-dependent manner. The aqueous extract at 400 mg/kg bw dose had a significant therapeutic (P<0.05) response. The study shows that the plant seeds have agents with both antimicrobial and antimalarial effects. [ABSTRACT FROM AUTHOR]