Isolation of antioxidant components from Corni fructus

Abstract

A 90% ethanol extract of Corni fructus was fractioned and the active components (i.e., morroniside, loganin) were isolated for functional food materialization. More specifically, the ethanol extract was fractioned according to the solvent polarity (i.e., n-hexane, ethyl acetate, and n-butanol), and the ethyl acetate fraction was found to exhibiti the highest antioxidant capacities (i.e., total phenolic content = 145.84 GAE mg/100 mL, DPPH radical scavenging activity = 7.91 mM GAE, FRAP activity = 18.86 mM TE, ABTS radical scavenging activity = 13.36 mM TE). Diaion HP 20 gel was used for separation of the ethyl acetate fraction, and 20%, 40%, 60%, and 80% ethanol fractions were also examined. The 40% ethanol fraction was found to exhibit the highest DPPH radical scavenging activity (10.22 mM GAE), ABTS radical scavenging activity (37.29 mM TE), and FRAP activity (27.32 mM TE) (p<0.05). The total phenolic compound content (580.84 GAE mg/100 mL), total flavonoid content (166.24 CE mg/100 mL), and total anthocyanin content (0.74 mg/100 mL) followed a similar trend, again being the highest for this fraction. Two components (i.e., morriniside, loganin) were identified in the ethyl acetate and 40% ethanol fractions, and their contents were determined by high-performance liquid chromatography. Furthermore, the 40% ethanol fraction contained the highest quantity of total active components (p<0.05), and the presence of morroniside (405 [M-H]and 451 [M+COOH-H]-) and loganin (389 [M-H]and 435 [M+COOH-H]-) were confirmed by ultra-performance liquid chromatography-mass spectrometry.