Résumé
Objective: To study the chemical constituents of the whole herbs of Sargassum fusiforme. Methods: The chemical constituents from S. fusiforme were separated and purified by silica gel, MCI, ODS, Sephadex LH-20 gel column chromatographies, and preparative HPLC. Their structures were identified by analysis of NMR, MS, ORD, etc, and comparing physicochemical properties of compounds with references. Results: A total of 19 compounds were obtained from the 50% ethanol-H2O extract of S. fusiforme, and their structures were determined as lupenone (1), bauerenone (2), β-amyrenone (3), α-amyrenone (4), loliolide (5), isololiolide (6), (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (7), (R)-dehydrovomifoliol (8), 24-ethylcholesta-4,24 (28)-dien-3-one (9), fucosterol (10), 29-hydroperoxystigmasta-5,24 (28)-dien-3β-ol (11), 24-hydroperoxy-24-vinylcholesterol (12), saringosterol (13), (24R)-5,28-stigmastadiene-3β,24-diol-7-one (14), dihydroquercetin (15), aurantiamide acetate (16), dibutyl phthalate (17), glycerol monopalmitate (18), and methyl hexadecanoate (19). Conclusion: The compounds isolated from S. fusiforme were mainly identified as triterpenoids, sesquiterpenoids, highly oxidized sterols, alkaloids and so on. Compounds 1-4, 7-8 and 14-19 are isolated from S. fusiforme for the first time.
Résumé
Objective To study the chemical constituents of brown alga Sargassum fusiforme.Methods The compounds were isolated by silica gel chromatography,ODS chromatography,and preparative HPLC,and their structures were elucidated on the basis of chemical and spectroscopic methods,including HR EI-MS,1D and 2D NMR spectral techniques.Results Six sterols and two glycolipids were isolated from the n-hexane soluble part of ethanol extract of S.fusiforme and their structures were identified as fucosterol(Ⅰ),24R,28R-and 24S,28S-epoxy-24-ethylcholesterol(Ⅱ),24-hydroperoxy-24-vinylcholesterol(Ⅲ),29-hydroperoxystigmasta-5,24(28)-dien-3?-ol(Ⅳ),(24S)-5,28-stigmastadien-3?,24-diol(Ⅴ),(24R)-5,28-stigmastadien-3?,24-diol(Ⅵ),1-O-myristoyl-3-O-(6′-sulfo-?D-quinovopyranosyl) glycerol(Ⅶ),and 1-O-palmitoyl3-O-(6′-sulfo-?-D-quinovopyranosyl) glycerol(Ⅷ).Conclusion This is the first report for the isolation of Ⅳ,Ⅶ,and Ⅷ from alga of Sargassum(Turn.) Ag.,and compounds Ⅱ and Ⅲ from this alga.The isomers of saringosterols 24S(Ⅴ) and 24R(Ⅵ) from this alga are obtained by preparative normal-phase HPLC for the first time.
Résumé
Objective Bioactive components were extracted from Sargassum fusiforme by using different solvents and their activities were detected in vitro in order to screen potential free radical scavenger.Methods Using the assay system of DPPH,superoxide radical,and in comparison with vitamin C,tea polyphenols and a series of extracts of sea tangle,laver.Results Different solvents had different extraction rates,and extracts by different solvents had different free radical scavenging activities.Conclusion 0.5%Na2CO3 solution had the highest extraction rate and extracts by this solution had the best scavenging ability as well.At the same time,the results obtained by DPPH detection method were more stable than those by the others.