Studies On The Chemical Constituents From Starfish Asterias Amurensis

Starfish has been known as the predominant source of marine products which widely distributes in all oceans and yields a large number of unique bioactive metabolites such as asteroids and saponins. These compounds with unique structures isolated from sea stars are demonstrated significant activities constituents such as anti-tumor,anti-inflammatory,immunomodulation,anti-allergy,anti-fungal,and anti-viral.In our continual studies of bioactivities of star fish Asterias amurensis collected from Qingdao China sea,we found the BuOH part of it's extraction shows significant anti-tumor activities in invtro and it has been studied in Japan and Russia from 1960s while only one article reported six asteroids in China.In order to take use of rich resource of Asterias amurensis in China and to study the chemical diffierences between Asterias amurensis from different sea areas,we collected 14 Kg of Asterias amurensis.The crude extracts of Asterias amurensis were separated employing solvent partitioning followed by various chromatographic methods including LPLC,MPLC,HPLC on silica gel column,ODS RP C18 and Sephadex LH-20 to afford 20 compounds.Structures of 12 compounds were elucidated on the basis of extensive spectroscopic analysis(MS,¹H-NMR,¹³C-NMR,HMQC,HMBC, 1H-1H-COSY,TOCSY and NOESY),named as forbeside F(1),3β-O-sulfated-6α, 23-diol-cholest-9(11) sodium salt(2),Amurensoside D(3),tryptophan(4),3β-O-sulfated-6α,23β-diol-cholesta-9(11)-en-23-one sodium salt(5),3β-O-sulfated-6α-ol-cholesta-9(11)-en-23-one sodium salt (6),3β-O-sulfated-6α-ol-ergost-9(11)-en-23-one sodium salt(7),3β-O-sulfated-cholesta-5(6)-en sodium salt(8),3-(octadecyloxy)-1,2-Propanediol(9),cholesterol(10),3β-ol-(22E,24R)-ergost -22-en(11) and 3β,5α,9α-trihydroxy-(22E,24R)-ergosta-7,22-dien-6-one(12).Compound 5 and 7 showed strong toxicity to Pyricularia oryzae P-2b with MMDC value less than 7.9μg/ml,the activities of compounds 2,6,8 were moderate and compound 3 showed almost least toxic to it.Considering the relation between bioactivities and structures of compounds,we can conclude that the structures with sulfated unit is toxic and with 20-OH strengthen the effert.All of these compounds except 5 to 8 were isolated from Asterias amurensis for the first time, and compound 2 is isolated from nature for the first time.Our studies focused on bioactive constiumtd of Asterias amurensis and established a foundation for further development of the kind starfish with abundant resources in Qingdao China Sea.