Abstract: In order to study the inhibitory effect of the pericarp extract of Euscaphis konishii Hayata on Pythium aphanidermatum.In this paper,based on the biological activity tracking method,a variety of chromatographic separation techniques and spectral identification analysis,18 compounds were isolated from E. konishii and identified as (7S, 8R)-dihdrodehydrodico-niferylalcohol4-O-β-D-glucopyranoside (1), evofolin-B (2), (7R,8R)-threo-7, 9, 9'-trihydroxy-3, 3'-dimethoxy-8-O-4'-neolignan4-O-β-D-glucopyranoside (3), illiciumlignan B (4), isorhamnetin (5), kaempferol (6), quercetin (7), quercetin-3-O-β-D-glucoside (8), isorhamnetin-3-O-β-D-rutinoside (9), xiafotoside (10), hibiscus-6-C-β-D-glucoside-8-C-α-pyranosin (11), 4-hydroxybenzaldehyde (12), vanillicacid (13), [R-(R*, R*)]-(1R)-[(4R)-4-hydroxy-2, 6, 6- trimethyl-1-cyclohexen-1-yl]-1-methylpropyl-β-D-glucopyranoside (14), (3E)-4-[(3R, 4R, 5R)-4-(β-D- glucopyranosyloxy)-3, 5-dihydroxy-2, 6, 6-trimethyl-1-cyclohexylen-1-yl]-3-buten-2-tone (15), roseoside (16), 1-(4-ethylphenyl)-1, 2-ethanediol (17), lolioide (18).Except for compounds 6-8,12-13,all others were isolated for the first time in this genus.Furthermore,the EC₅₀ of compounds 1,9-11 against P. aphanidermatum were between 56.06-123.94 μM.The EC₅₀ value of compound 9 against P. aphanidermatum was 56.06 μM,which was equivalent to the activity of the positive control drug eugenol.In this study,it was found for the first time that the extract of E. konishii had a good inhibitory effect on P. aphanidermatum,which indicated that the flavonoid glycosides were the important components of this plant.

Key words: Euscaphis konishii Hayata, pericarp, constituents, Pythium aphanidermatum, antifungi