title: A potent anti-complementary acylated sterol glucoside from Orostachys japonicus.
abstract: In order to isolate substances that inhibit the hemolytic activity of human serum against erythrocytes, we have evaluated whole plants of the Orostachys japonicus species with regard to its anti-complement activity, and have identified its active principles following activity-guided isolation. A methanol extract of the O. japonicus, as well as its n-hexane soluble fraction, exhibited significant anti-complement activity on the complement system, which was expressed as total hemolytic activity. A bioassay-guided chromatographic separation of the constituents resulted in the isolation of three known compounds 1-3 from the active n-hexane fraction. The structure of these compounds were analyzed, and they were identified as hydroxyhopanone (1), beta-sitosteryl-3-O-beta-D-glucopyranosyl-6'-O-palmitate (2), and beta-sitosteryl-3-O-beta-D-glucopyranoside (3), respectively. Of these compounds, compound 2 exhibited potent anti-complement activity (IC50= 1.0 +/- 0.1 microM) on the classical pathway of the complement, as compared to tiliroside (IC50= 76.5 +/- 1.1 microM), which was used as a positive control. However, compounds 1 and 3 exhibited no activity in this system.
authors.affiliation: Faculty of Food Science and Biotechnology, Pukyong National University, Busan 608-737, Korea.
authors.forename: Na Young
authors.initials: NY
authors.lastname: Yoon
authors.forename: Byung Sun
authors.initials: BS
authors.lastname: Min
authors.forename: Hyeong Kyu
authors.initials: HK
authors.lastname: Lee
authors.forename: Jong Cheol
authors.initials: JC
authors.lastname: Park
authors.forename: Jae Sue
authors.initials: JS
authors.lastname: Choi
mesh_terms: D001578:Benzopyrans / Q000494:pharmacology; D051056:Complement Inactivating Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D003171:Complement Pathway, Classical / Q000187:drug effects; D029627:Crassulaceae / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D020128:Inhibitory Concentration 50; D007723:Korea; D008297:Male; D010168:Palmitates / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D012855:Sitosterols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D001578:Benzopyrans; D051056:Complement Inactivating Agents; D005419:Flavonoids; D005960:Glucosides; D010168:Palmitates; D010936:Plant Extracts; D012855:Sitosterols; C511123:beta-sitosteryl-3-O-beta-D-glucopyranosyl-6'-O-palmitate; C472604:sitosterol-3-O-glucopyranoside; C052083:tiliroside