title: Hepatoprotective constituents of the edible brown alga Ecklonia stolonifera on tacrine-induced cytotoxicity in Hep G2 cells.
abstract: In this study, ethanolic extracts from 18 seaweed variants were assessed for hepatoprotective activity against tacrine-induced cytotoxicity in Hep G2 cells. Only one of these, Ecklonia stolonifera Okamura (Laminariaceae), a member of the brown algae, exhibited promising hepatoprotective activity. Bioassay-guided fractionation of the active ethyl acetate (EtOAc) soluble fraction obtained from the ethanolic extract of E. stolonifera, resulted in the isolation of several phlorotannins [phloroglucinol (1), eckstolonol (2), eckol (3), phlorofucofuroeckol A (4), and dieckol (5)]. Compounds 2 and 4 were determined to protect Hep G2 cells against the cytotoxic effects of tacrine, with EC50 values of 62.0 and 79.2 microg/mL, respectively. Silybin, a well characterized hepatoprotective agent, was used as a positive control, and exhibited an EC50 value of 50.0 microg/mL. It has been suggested that the phlorotannins derived from marine brown algae might prove useful sources in the development of novel hepatoprotective agents.
authors.affiliation: College of Pharmacy, Wonkwang University, Iksan, Korea.
authors.forename: Youn Chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Ren Bo
authors.initials: RB
authors.lastname: An
authors.forename: Na Young
authors.initials: NY
authors.lastname: Yoon
authors.forename: Taek Jeong
authors.initials: TJ
authors.lastname: Nam
authors.forename: Jae Sue
authors.initials: JS
authors.lastname: Choi
mesh_terms: D001572:Benzofurans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D005591:Chemical Fractionation / Q000379:methods; D004146:Dioxanes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D004147:Dioxins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000431:Ethanol / Q000737:chemistry; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D020128:Inhibitory Concentration 50; D008099:Liver / Q000187:drug effects* / Q000473:pathology; D000459:Phaeophyceae / Q000737:chemistry*; D010696:Phloroglucinol / Q000737:chemistry / Q000494:pharmacology; D020011:Protective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000077385:Silybin; D012838:Silymarin; D013619:Tacrine / Q000494:pharmacology; D013634:Tannins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D001572:Benzofurans; D004146:Dioxanes; D004147:Dioxins; D006576:Heterocyclic Compounds, 4 or More Rings; D020011:Protective Agents; D012838:Silymarin; D013634:Tannins; C507565:eckstolonol; C064093:phlorofucofuroeckol A; D000431:Ethanol; D000077385:Silybin; D013619:Tacrine; D010696:Phloroglucinol