Investigation of Livistona decipiens Leaf Methanol Extract and Evaluation of Antioxidant, Antimicrobial and Cytotoxic Activities

Abstract

Objectives: This study aimed to isolate the polyphenolic constituents from the methanol extract of Livistona decipiens Becc leaves and evaluate the antioxidant, cytotoxic and antimicrobial activities of the total methanol extract and ethyl acetate fraction Methods: The ethyl acetate and n-butanol fractions of Livistona decipiens leaf methanol extract were subjected separately to different chromatographic separation techniques. Structures of the isolated compounds were established by different spectroscopic techniques (1H / 13C NMR). Antioxidant activitywas evaluated by DPPH assay, while evaluation of cytotoxicity was done according to MTT cell viability assay. Antimicrobial activity was done by agar diffusion method. Results: seven compounds were isolated from the ethyl acetate and n-butanol fractions, they were identified for the first time from the plant as apigenin-8-C-β-D-glucopyranoside (Vitexin) (1), Quercetin-6-C-β-D-glucopyranoside (2),apigenin-6,8-di-C-β-D-glucopyranoside (Vicenin II) (3), 6-O-methyl Kaempferol 3-O-glucopyranoside (4), luteolin-3-C-gentiobiosyl (5),luteolin-6-C-β-D-glucopyranoside (Isoorientin) (6) and luteolin-8-C-β-D-glucopyranoside (Orientin) (7). The ethyl acetate fraction has shown moderate activity against Gram positive and Gram negatvie bacteria, also it showed moderate antioxidant activity with IC50 = 23 ± 0.74 µg/ml when compared to ascorbic acid IC50 = 14.2 ± 0.35 µg/ml. Also ethyl acetate extract has shown cytotoxic activity on MCF-7 cells (human breast cancer cell line), HepG-2 (human hepatocellular carcinoma) and HeLa cells (human cervical cancer cell line), whereas, the methanol extract has shown lower activity. Conclusion: Livistona decipienshave potential medicinal value being rich in polyphenolics and beingantioxidant, cytotoxic and antimicrobial drug.