Antimicrobial and cytotoxic activities of Alnus rugosa L. aerial parts and identification of the bioactive components

Abstract

This present investigation was undertaken to study antimicrobial and cytotoxic activities of dichloromethane, ethyl acetate, and methanol 80% extracts from Alnus rugosa L. aerial parts, as well investigate the bio-active compounds of each extract. Antimicrobial activity of the mentioned extracts against various bacteria and fungi using microdilution method, and cytotoxicity against five different human tumor cell lines, and in a non-tumor liver cells primary culture were tested. Extracts were subjected to phytochemical analysis and column chromatography eluted with different solvents, n-hexane, dichloromethane, ethyl acetate, and methanol gradually. The results showed that the extracts had a significant antimicrobial activity against all the tested bacteria and fungi, and proved a significant cytotoxic effect. Methanol 80% extract exhibited the highest antibacterial effect, and ethyl acetate extract was the most active as antifungal agent while dichloromethane extract showed the lowest antifungal effect. Dichloromethane extract was the most active against all the tested tumor cell lines. Chromatographic separation of dichloromethane extract of A. rugosa aerial parts resulted in the isolation and identification of β-sitosterol, β-sitosterol 3-O-β-glucoside and apigenin, while from ethyl acetate extract, diosmetin, naringenin, luteolin, and luteolin 7-O-β-glucoside were identified, and from methanol 80% extract, quercetin 3-O-α-rhamnoside, isorhamnetin 3-O-β-glucoside and isorhamnetin 3-O-β-glucoside 7-O-α-rhamnoside were identified. In conclusion, the present research provided significant information about antimicrobial and cytotoxic activities and compounds isolated from A. rugosa aerial parts extracts.