Background: Natural products play a significant role in human therapy. They represent a huge reservoir of bioactive chemical diversity and help in understanding the cellular pathways that are essential component of drug discovery process. Objective: This study was aimed at evaluating the antimicrobial activity of stigmasterol isolated from the stem bark of Neocarya macrophylla. Methods: Stigmasterol previously isolated from the stem bark of N. macrophylla was subjected to antimicrobial screening against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), S. aureus, Streptococcus faecalis, Escherichia coli, Salmonella typhimurium, Pseudomonas fluorescens, Klebsiella pneumoniae, Candida albicans and Candida krusei using agar diffusion and broth dilution methods. Results: Susceptibility test results showed that the compound (100 μg/mL) inhibited the growth of all the test organisms with mean zone of inhibition range from 23 mm to 30 mm except the VRE, S. typhi and K. pneumoniae. The activity of stigmasterol was compared with that of ciprofloxacin (5 μg/mL), the standard antibacterial drug, and fluconazole (5 μg/mL), the antifungal agent. The test compound displayed a broad-spectrum of activity, and in many cases exhibited comparable antibacterial activity when compared to ciprofloxacin. Interestingly, the compound also showed antifungal activity against Candida spp., affording comparable inhibitory effect as fluconazole. The minimum inhibitory concentration (MIC) and the minimum bactericidal/fungicidal concentration (MBC/MFC) of stigmasterol range from 6.25 μg/mL to 25 μg/mL and from 12.5 μg/mL to 50 μg/mL, respectively. Conclusion: These properties suggest that the isolated stigmasterol is a potent and broad-spectrum antibacterial and antifungal agent and as such may serve as a lead compound in the development of novel antimicrobial drugs.

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Stem bark of Ficus exasperata was extracted using ethyl acetate by microwave-assisted solvent extraction. Phytochemical screening and antimicrobial evaluation were carried out on the extract. Phytochemical screening revealed the presence of cardiac glycosides, tannins, flavonoids, triterpenes and steroids. Antimicrobial evaluation revealed that the extract is active against Methicillin – resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Streptococcus pneumoniae, Salmonella typhi, Proteus mirabilis, Shigella dysenteriae, Candida stellatoidea and Candida tropicalis. The zones of inhibition (mm) for the test organisms were (24 - 31) mm. Minimum inhibition concentrations (mg/L) of extract against MRSA, Staphylococcus aureus, Streptococcus pneumonia, Salmonella typhi, Proteus mirabilis, Shigella dysenteriae, Candida stellatoidea and Candida tropicalis were 2.5, 1.25,1.25, 2.5, 1.25, 1.25, 1.25 and 2.5 respectively. Minimum bactericidal concentrations (mg/L) of extract against Methicillin – resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Streptococcus pneumonia, Salmonella typhi, Proteus mirabilis Shigella dysenteriae Candida stellatoidea and Candida tropicalis were 5, 2.5, 2.5, 5, 5, 2.5,2.5 and 5 respectively. The extract showed high inhibition against MRSA and Candida tropicalis.

Diabetes Mellitus is a chronic metabolic disorder characterized by hyperglycemia due to abnormal insulin secretion, action or both. The synthetic available anti-diabetic drugs exhibited various adverse effects such as diarrhea, hypoglycemia. In recent years, scientists have turned their attention towards the medicinal plants which bear the rich source of metabolites which offer specific therapeutic function in the human body without any adverse effect. Sterculia setigera and Ficus platyphylla are medicinal plants that are used to treat various diseases and including diabetes traditionally. The present study is aimed at investigating the antidiabetic activity of the S. setigera and F. platyphylla methanol stem bark extracts. Phytochemical screening was determined using the standard method. In vitro studies were carried out using αamylase and glycosylated hemoglobin inhibitory assay. The results of phytochemical constituents detected were flavonoids, Tannins, Steroids, Saponins, cardiac glycosides, Terpenoids, and Phenols. Inhibitory effects of both plant extracts were dose dependent against haemoglobin glycosylation and α-amylase. At highest concentration (25mg/ml), highest inhibitions were recorded in S. setigera (70.30%) and F. platyphylla (70.00%) which was comparable to Metformin (57. 2%). IC 50 of Sterculia setigera (3.18mg/ml) and Ficus platyphylla (5.97mg/ml) were lower than metformin (8.84 mg/ml) against hemoglobin glycosylation. At concentration of (1.0mg/ml) S. setigera (72.21%) and F. platyphylla the (70.41%) showed the highest inhibitory effect which was not significantly different (p<0.05) compared to Voglibose (83.47%). In the present study, the IC 50 of both extracts were higher (0.64 and 0.69mg/ml) and not significantly comparable to the Voglibose (0.26mg/ml). In conclusion, this study suggests that Sterculia setigera and Ficus platyphylla methanol stem bark extract possess hypoglycaemic potentials. This justifies their ethnomedicinal use for the treatment of diabetes.