Identification And Chemical Constituents Of Amarineactinomycetes Strain H41-55

This study focused on a strain of Streptomyces sp.H41-55,which was isolated from the marine mangrove sediments,and found that it had antifungal activity by bioactive screening.Then,it was systematically classified and identified.The optimization of culture conditions and the chemical componentsand their activity of large scale fermentation products for this strain were studied.The research content and results are presented as follows:(1)Based on Streptomyces Identification Manual,the strain H41-55 and the strain Streptomyces antibioticus were found to be similar on the basis of a comparison of the culture,morphological,physiological and biochemical characteristics under the corresponding culture conditions.Besides,the similarity of the 16 S rDNA sequence of strain H41-55 to Streptomyces antibioticus was as high as 99%.Thus the strain H41-55 was determined to be Streptomyces antibioticus.(2)Based on the growth morphology of the strain,the yield and the antifungal capacity of the culture product,several commonly used mediums were systematically evaluated.It is found thatthe best seed culture medium was determined,the optimum growth temperature was 30?,and the best incubation time was 4 days.Finally,a total of 60 L volumeof the fermentation product was obtained by large scale fermentation inthe optimum conditions.(3)The fermentation product of H41-55 was used to isolate and purifythe metabolites by silica gel,ODS,Sephadex LH-20 gel column chromatography,and semi-preparative HPLC.Finally,21 pure compounds were obtained.The structures of the isolated compounds were identified on the basis of IR,UV,MS and NMRmethods.They were determined to be(2S,3R)-L-threonine-N-[3-(formylamino)-2-hydroxybenzoyl]-propyl ester(1),antimycin A9(2),kitamycin A(3),actionmycin D(4),actinomycin X2(5),indole-3-formaldehyde(6),5-hydroxy-3-(1-hydroxy-2-methylbutyl)-4-methyl-2(5H)-furanone(7),cyclo-(L-Pro-L-Leu)(8),seco-(S–Pro-R-Val)(9),cyclo-(S-Pro-8-hydroxy-R-Ile)(10),6-(3-methyl-2-butenyl)-3-Indoleacetonitrile(11),ubiquinone Q9(12),ergosta-7,22-diene-3?,5?,6?-triol(13),ergosta-8(14),22E-diene-3?,5?,6?,7?-tetraol(14),stigmasterol-7,22-diene-3?,5?,6?-triol(15),5?,6?-epoxy-(22E,24R)-ergosta-8,22-diene-3?,7?-diol(16),5a,6a-Epoxy-(22E,24R)-ergosta-8,22-diene-3?,7?-diol(17),ergosta-7,22-diene-3?,5?,6?,25-tetraol(18),3?,5?,9?-trihydroxy-(22E,24R)-ergosta-7,22-diene-6-one(19),ergosta-4,6,8(14),22-tetraen-3-one(20)and(22E,24R)-ergosta-4,7,22-trien-3-one(21).(4)The isolated compounds were assayed for antifungal and cytotoxic activities.The results showed that compounds 2~5,12,20 and 21 had certain antifungal activity.Compounds 1~5,7,12 and 20 had certain antitumor activity.