Antibacterial Activity of n-Hexane Extract of Ocimum gratissimum leaves

Abstract

The antibacterial activity of n-hexane extract of Ocimum gratissimum leaves was investigated against gram neg. bacteria (Salmonella typhi) and gram pos. bacteria (Staphylococcus aureus). Agar well diffusion and broth dilution methods were employed. The results revealed that both first and second n-hexane extracts (4days and 8 days n-hexane extract resp.) inhibited the microorganisms with the second being more active as it inhibited at 30mg/mL, 40mg/mL, 50mg/mL and 100mg/mL with zone of inhibition ranging from 8.5mm to 15.5mm in diameter The first extract showed no inhibition at 30mg/mL and 40mg/mL resp. but showed inhibition at 50mg/mL and 100mg/mL with zone of inhibition ranging from 9mm to 12mm in diameter The Min. Inhibitory Concentration (MIC) of the second n-hexane extract ranged from 25mg/mL to 100mg/mL whereas, that for the first was at 100mg/mL. The result was compared to conventional drug (Gentamicin 20ug/mL) with zone of inhibition at 20mm in diameter The Gas Chromatog. Mass Spectrometry (GC/MS) identified antibacterial compounds which include Hexadecanoicacid, Phytol, Ricinoleicacid, Dehydrodihydrodiisoeugenol and 9-Octadecenamide. Based on the results it can be concluded that Ocimum gratissimum leaves extract possess antibacterial activity and can be applied in development of potent antibacterial drugs.