Assessment of synergistic anti-bacterial and anti-oxidant activities of essential oil extracted from peels of citrus reticulata, citrus sinensis and citrus lemon

Nature provides a variety of drugs and medicinal agents derived from different parts of plants. Citrus plants have different medicinal properties. Essential oils extracted from peels of different citrus fruits are used to treat number of diseases like bacterial, fungal, insecticidal and diabetic etc. The present study was conducted to check the antibacterial and antioxidant properties of essential oils extracted from peels of Citrus reticulata, Citrus sinensis and Citrus lemon and their mixture. The composition of the essential oils was determined by GC/MS which showed that limonene, manitol, pinene and pyrazinoic acid were dominant among others. Their antibacterial activity was checked against Staphylococcus aureus, E. coli and Salmonella enteritidis. Well diffusion assay was performed to check the antibacterial activity. Citrus lemon was found active against Staphylococcus aureus while mixture showed highest antibacterial activity against all microbes. 5mg/ml of essential oils of mixture showed antibacterial activity against Salmonella enteritidis and E. coli while 10mg/ml of essential oil showed antimicrobial activity against Staphylococcus aureus. Their antioxidant activity was checked by DPPH assay. Different concentrations (20-100µg/ml) were used for evaluating antioxidant potential. 100µg/ml of sample showed highest antioxidant activity while using ascorbic acid as standard.