호두의 품종 및 추출 용매에 따른 항균 및 항산화 활성

Abstract

Walnut exhibits greater antioxidant capacity than any other nuts. However, antioxidant and antimicrobial capacities on the organic solvent fractions and different cultivars of walnut is unknown. The aim of the present study is to elucidate the antioxidative and antimicrobial activities on solvent fractions (Hexane, CHCl3, EtOAc, n-Butanol, Water) obtained from the MeOH extracts of two walnut cultivars ( Ju gl an s si n en si s Dode cv. Gwangdeok, J ug l an s s i nen s i s Dode cv. Sinlyeong). Antimicrobial activities were assessed using the zone of inhibition test, and antioxidant activities were determined by the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. The ethyl acetate fraction showed strong antibacterial effect against E. f ae ci u m MD8b, S. aur eu s SG511 and P. aer ug i no sa 1771. Meanwhile, water fraction showed high antimicrobial activity against E. co l i O78. DPPH radical scavenging activities showed the highest effect in the ethyl acetate fraction among the five fractions and MeOH extract from two walnut cultivars. The EtOAc fraction of Sinlyeong walnut kernel showed antioxidant potential of EC50 3.89 g/mL higher than that of μ L-ascorbic acid (Vitamin C) EC50 8.42 g/mL. The EtOAc fraction of Sinlyeong walnut kernel μ have two times higher antioxidant potential than L-ascorbic acid. The EtOAc fraction of Sinlyeong walnut kernel showed more antibacterial and antioxidant effects than Gwangdeog walnut kernel. These results indicate that EtOAc fraction of Sinlyeong walnut kernel is most effective potential against bacterial growth and oxidative stress.