Evaluation of antimicrobial and antioxidant activity of β-Sitosterol-3-O-Glucoside isolated from Lannea Kerstingii Engl. & K. Krause (Anacardiaceae).

Abstract

β-sitosterol-3-O-glucoside was isolated using dry vacuum liquid chromatography. It was characterized using 1H-NMR, 13C-NMR and 2D NMR spectra. The antimicrobial activity was determined using agar diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) were determined using broth dilution method. Antioxidant activity was determined through reaction of compound with DPPH radical. The compound was active against S. aureus, Methicillin Resistant Staphylococcus aureus, P. mirabilis, S. typhi, K. pneumoniae, E. coli, B. subtilis, C. albicans and C. tropicalis with zone of inhibition ranging from 22.0 ± 0.4 to 34.0 ± 0.3 mm and inactive against P. aeroginosa, Proteus vulgaris and C. krusei. The MIC ranged from 25.0 to 50.0 μg/ml while the MBC/MFC ranged from 50.0 to 200.0 μg/ml. The % DPPH scavenging activity at 4.0x103 μg/ml was found to be 81.44 ± 0.41 %. This result shows the high antioxidant and wide spectrum antimicrobial activity of β-sitosterol-3-O-glucoside which can be a potential lead drug for resistant bacteria such as MRSA, and a potential source of natural antioxidants.