Evaluation of antioxidant and antimicrobial potential of strawberry tree (Arbutus Unedo L.) leaf

In present study, antioxidant and antimicrobial activities of strawberry tree (Arbutus unedo L.) leaves were investigated. Antioxidant activity was determined by methods of DPPH scavenging, beta-carotene bleaching, reducing power, metal chelating, superoxide anion scavenging, and hydrogen peroxide scavenging activity. Total phenolic content were determined to be 197.16 +/- 1.43 mg GAE/g extract in aqueous extract. The EC50 value of methanolic extracts was found to be 0.423 mg/mL. The extracts of leaves showed nearly 1/4 metal chelating capacity of standard EDTA, high reducing power, superoxide anion scavenging, and hydrogen peroxide scavenging activities. While the strawberry tree leaves exhibited antibacterial activity against Staphylococcus aureus, there was no inhibitory effect against Escherichia coli and Salmonella enteritidis. The strawberry tree leaves exhibited antifungal effect against 2 aflatoxigenic molds namely Aspergillus parasiticus NRRL 2999 and NRRL 465. These results suggest that the strawberry tree leaves may be used as an antioxidant source for pharmaceutical application, nutraceutical and functional food industries