Anticancer, anti HIV-1 and antimicrobial potentials of methanol extract and non polar fractions of Citrus volkameriana leaves and phytochemical composition

Abstract

This study investigated anticancer, anti HIV-1, antimicrobial potentials and the phytochemical composition of the total methanol extract, petroleum ether (60-80°C) and dichloromethane fractions of Citrus volkameriana leaves. Anticancer activity was measured by a sulforhodamine B (SRB) assay. Syncytia formation assay was used to evaluate anti-HIV -1 potential and antimicrobial assay was performed according to Buwa and Van staden with some modifications. The results showed that petroleum ether fraction exerted growth inhibitory effect on melanoma cancer cell line (UACC62), it inhibited the syncytia formation of HIV-1 with EC 50 of 17.4 μg mLG1 and also it inhibited the growth of Micrococcus luteus B-287 and Bacillus subtilis with Minimum Inhibitory Concentrations (MIC) of 31.25 and 62.5 μg mL -1, respectively. While dichloromethane fraction inhibited the growth of Micrococcus luteus with MIC of 62.5 μg mL -1. Phytochemical investigation of petroleum ether fraction yielded six compounds, (1) α-amyrin, (2) β-sitosterol, (3) 5-O-demethylnobiletin, (4) 4', 5-dihydroxy-6, 7, 8, 3'-tetramethoxy flavone, (5) Tangeretin and (6) Nobiletin while five compounds were isolated from dichloromethane fraction including, (7) 4', 5-dihydroxy-3', 6, 7-trimethoxyflavone (cirsilineol), () luteolin 7-O-methyl ether, (9) Hesperitin, (10) 4'-hydroxy -5, 6, 7-trimethoxy flavone and (11) β-sitosterol 3-O-β-D-glucoside. The compounds 7, 8 and 10 were isolated for the first time from Rutacea family. This study provides promising results for C. volkameriana leaves in treatment of tumors, microbes and HIV/AIDS-related opportunistic infections.