Comparing total anthocyanins, total phenolics and antioxidant activities of extracts (aqueous, organic and anthocyanin) obtained from pomegranate (peel, juice, and seed) and antimicrobial activity of peel extracts on the four pathogenic bacteria

Abstract

Nowadays, consumers are highly worried about using chemical preservatives in foods. Thus they tend to use natural and safe food products with healthful benefits. Pomegranate and its peel can have such a role. This study aimed to determine the antioxidant activity, total phenolics, and flavonoids properties of different parts of pomegranate extracts. Three types of extracts were prepared with different solvent (water extract, organic and anthocyanin extract). The total phenolic and antioxidant activities were highest in peels, intermediate in juice and lowest in seeds and total anthocyanin was highest in juices. The organic extracts have the highest antioxidant activity. Then we examined the antimicrobial activity of peel extracts (organic, aqueous and anthocyanin extracts) and determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) on two gram-positive bacteria <em>Staphylococcus aureus</em> and <em>Bacillus cereus</em> and two gram-negative bacteria <em>E. coli</em> and <em>Salmonella typhi</em> using liquid dilution susceptibility testing method. Thus, 62.5 ppm MIC of the organic and anthocyanin extracts of the peel was useful in <em>Staphylococcus aureus </em>and<em> Salmonella typhi</em> bacteria. Furthermore, organic and anthocyanin extracts of the peel at a concentration of 125 ppm had bactericidal effects on <em>Staphylococcus aureus</em> and <em>E. coli</em> bacteria and <em>Bacillus cereus</em> and <em>Salmonella typhi</em> at a concentration of 250 ppm. Thus, one can state that pomegranate peel extracts have high antibacterial effects because of high phenolic compounds and high levels of anthocyanin with high antioxidant activities.