Studies On The Water-soluble Constituents Of Rumex Japonicus Houtt. And Eriobotrya Japonica

This paper consisted of two parts. In the first part on the study of water-solubleconstituents of the root of Rumex japonicus Houtt.,15 compounds have been isolatedand elucidated by the spectral and chemical analysis, among which 6 new compoundsrespectively named as rumejaposide A, B, C, D, E, 3-acetyl-2-methyl-1,4,5-trihydroxy-2,3-epoxy naphthoquinol. 9 known compounds were determined as2,6-dihydroxy benzoic acid , 5,7-dihydroxy-3H-chromene-2,4-dione, 4-hydroxybenzoic acid, epicatechin,4-hydroxy-3-methoxy benzoic acid, 2,6-dimethoxy-4-hydroxy benzoic acid, rutin, emodin, 2-acetyl-1,8-dihydroxy-3-methyl-6-methoxynaphthalene (TRA), in which, 2,6-dihydroxy benzoic acid,5,7-dihydroxy-3H-chromene-2,4-dione, 4-hydroxy benzoic acid, epicatechin,4-hydroxy-3-methoxybenzoic acid, 2,6-dimethoxy-4-hydroxy benzoic acid were isolated from the root ofRumex japonicus Houtt. for the first time. It was reported that oxanthrone 10-Cglycosides showed cytotoxic activity, but we didn't detect any antitumor activityagainst HL-60 and A-549 cells. Additionally when rumejaposide A, C, D,epoxynaphthoquinol , 5,7-dihydroxy-3H-chromene-2,4-dione, 4-hydroxy benzoicacid,TRA detected antioxidative activity by scavenging the DPPH free radical, onlyTRA showed some activity between quercetin and BHT. Rumex japonicus Houtt. is afolk medicine to treat some antifungal diseases , but We didn't detect any antifungalactivity against Candida albicans and Trichophyton rubrum with rumejaposide A, B,C, D, E, epoxynaphthoquinol, TRA.In the second part on the study of water-soluble constituents of the leaves ofEriobotrya japonica , 10 compounds have been isolated and elucidated by the spectraland chemical analysis with 1 new compound named as5,5'-dihydroxy-3'-methoxy-2-O-β-D-glucopyranosylbiphenyl. 9 known compoundswere epicatechin, 3-caffeoylquinic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid,lyoniside, quercetin 3-O-sophoroside, kaempeful 3-O-sophoroside, kaempeful3-O-neohesperidoside, quercetin 3-O-glucoside and lyoniside was isolated from theleaves of Eriobotrya japonica for the first time. Biphenyls were known as phytoalexininduced by fungal inocubation or natural infection. In Eriobotrya japonica, there wassurprising variation in the phytoalexin response of different tissues. As reported, thecortex produced the biphenyl aucuparin and the leaves produced a dibenzofuran, butthere was not any phytoalexin response detected in sapwood. We isolated thebiphenyl glycoside from the leaves for the first time. Unfortunately, it showed noantifungal activity against Candida albicans and Aspergillus niger. When detected theantioxidative activity by scavenging DPPH free radical, quercetin glycosides showedmuch stronger ability than kaempeful glycosides. Besides, three chlorogenic acidisomers, epicatechin and quercetin exhibited almost the same antioxidative activities.