Antioxidant and Antimicrobial Effects of Extract with Water and Ethanol of Oriental Melon (Cucumis melo L. var makuwa Makino)

The biological activities of water and ethanol extracts from different fruit parts, such as peel, flesh, and placenta of oriental melon were investigated. The total phenolic concentration of water extract was the highest such as 151.64 mu g/g in the peel, also that of ethanol extract was 224.77 mu g/g in the peel, respectively. The total flavonoid content in the water and ethanol extracts were high such as 45.53 mu g/g and 67.16 mu g/g of peel, respectively. In the physiological activities, DPPH in the water and ethanol extracts were high such as 25.0% and 83.3% of peel in 1% concentration. Extract of peel was higher than those of flesh and placenta. ABTS in the water extracts was 79.2% of peel, 57.6% of flesh and 74.0% of placenta in 1% concentration. Ethanol extracts was 99.9% of peel, 52.1% of flesh and 41.2% of placenta in 1% concentration. In addition, xanthine oxidase inhibitory activity and alpha-Glucosidase inhibition activity of the peel of water and ethanol extracts appeared to be higher than those of placenta and flesh. This study showed that the antioxidant and alpha-Glucosidase inhibition activity of peel extracts were higher than those of placenta and flesh. Also, the antimicrobial effect of ethanol extract from different fruit parts was shown only on Streptococcus agalactiae.