Evaluation of antioxidant and antibacterial activities of morin isolated from mulberry fruits (Morus alba L.)

Antioxidant and antibacterial activities of materials isolated from the methanol extract of mulberry fruits were evaluated. The active constituent of the methanol extract derived from mulberry fruits was isolated by silica gel and LH-20 column chromatographies and was identified as morin by electron ionization mass spectrometer, 1H-NMR, and 13C-NMR spectroscopy. Based on the IC50 values, the antioxidant activities of morin exhibited potent inhibition according to 1,1-diphenyl-2-picrylhydrazyl (30.0 μg/mL) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (71.0 μg/mL) radical scavenging assays. Furthermore, the antibacterial activity of morin showed moderate (++) inhibition against Streptococcus mutans at both 5 and 2 mg/disc, according to paper disc diffusion assays, indicating morin isolated from mulberry fruits could be a useful natural agent for the management of antioxidant and antibacterial treatments.