Antimicrobial activity of Acorus calamus L. rhizome extract and its total flavonoid and phenolic contents

Abstract

Acorus calamus L. rhizome has potential activity as an antimicrobial agent. This study aims to evaluate the antimicrobial activity of the rhizome extracts and its total flavonoid and phenolic contents. Extraction was carried out by using ethanol at room temperature followed by fractionation into n-hexane, ethyl acetate, and n-butanol. Antimicrobial activity towards Escherichia coli, Staphylococcus aureus, and Candida albicans were evaluated by agar diffusion method. Total flavonoid and phenolic contents were determined by UV-Vis Spectrophotometer using the standard of quercetin and gallic acid, respectively. The A. calamus rhizome ethyl acetate fraction strongly inhibited Escherichia coli, Staphylococcus aureus and Candida albicans, followed by n-butanol and n-hexane fractions, respectively. There was no inhibition of water fraction towards all the microbes. Total flavonoid contents of ethyl acetate, butanol, n-hexane, and water fractions were successively 2978.34, 399.07, 142, 23, and 14.80 mg QE/100g, while total phenolic contents of those fractions were 1820.51, 329.71, 237.81, and 74.36 mg GAE/100g, respectively. The results show that there is a positive correlation between antimicrobial activity and its total flavonoid and phenolic contents.