title: Anti-allergic effects of ethanol extracts from brown seaweeds.
abstract: Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum graminifolium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC(50)) of Pakistani SC and ST were 109.5 and 21 microg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 microg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC(50)=39 microg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC(50)=20 microg/ml. The IC(50) of ST extract was found similar to that of catechin (21 vs 20 microg/ml) and lower than that of DSCG (21 vs 39 microg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.
authors.affiliation: Food Safety Laboratory, College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China.
authors.forename: Haider
authors.initials: H
authors.lastname: Samee
authors.forename: Zhen-xing
authors.initials: ZX
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Lin
authors.forename: Jamil
authors.initials: J
authors.lastname: Khalid
authors.forename: Yong-chao
authors.initials: YC
authors.lastname: Guo
mesh_terms: D018926:Anti-Allergic Agents / Q000494:pharmacology*; D006821:Hyaluronoglucosaminidase / Q000037:antagonists & inhibitors*; D012624:Seaweed / Q000737:chemistry*; D013634:Tannins / Q000032:analysis / Q000494:pharmacology
chemical_list: D018926:Anti-Allergic Agents; D013634:Tannins; D006821:Hyaluronoglucosaminidase