Study On The Bioactive Metabolites From Endophyte

Endophyte is a special and important group of microorganisms with taxonomic diversity, which can produce various of bioactive substances, including insecticidal, antimicrobial and antitumor compounds etc. In this research work, from a large amount of endophytes which had been screened based on several models, dozens of strains showed activities. Three of which were taxonomically identified, and their secondary metabolites were studied.7040 fermentation samples were prepared from 770 strains of endophytes. Through thouthands of screening on 14 different models, 16 samples showed activities. Among them, strain HCCB00167 and HCCB00189 showed strong bioactivity against HIV-1 integrase and strain HCCB01546 showed high inhibition to tumor cells. These three strains were selected for further study.According to their morphology, cultural characteristics and 18S rDNA sequences, HCCB00167, HCCB00189 and HCCB01546 were indentified as Myceliophthora cost, Acremonium and Leucostoma, respectivelyThe secondary metabolites of these three strains were isolated and purified. From HCCB00167, seven compounds. named as HCCB00167-1-7, were purified and identified as 5,8- epidioxyergosta -6,22-diene-3-ol, ergosta-5,7,22-trien-3-ol. 3,22,24-trihydroxy-olean-12-ene, 4'-hydroxy-7-methoxyisoflavone (Isoformononetein), 4',5-dihydroxy-7methoxyisoflavone(Prunetin), and 4-butylpicolinic acid respectively. Compound HCCB00167-7 was first found to be produced by this kind of endophyte.From strain HCCB00189, five compounds were purified and designated as HCCB00189-1-5, their structures were determined and elucidated as 4-methylbenzoic acid carboxymethyl ester, 4-methoxycarbonyl benzoic acid, 4-hydroxymethyl benzoic acid, 4',7-dihydroxyisoflavone(Daidzin). 4\5,7-trihydroxy-7rnethoyisoflavone(Genistein) respectively. Among them, compounds HCCB00189-1,2,3 were first found from metabolites of this kind of microbe. Compound HCCB00189-4 and HCCB00189- 5 showed strong cytotoxyties against A549 and LoVo cell lines, and their IC50 of this two cell lines were detected.From strain HCCB01546, six compounds (HCCB01546-A-F) were purified and elucidated as: ergosta-5,7,22-trien-3-ol, 5,8-epidioxyergosta-6,22-diene-3-ol, epoxycytochalasin H, cytochalasin N and epoxycytochalasin J, respectively. Among them, HCCB01546-C,D,E were first found from Leucostoma moteblites. Compound HCCB01546-B, HCCB01546-C and HCCB01546-E showed strong cytotoxyties against A549 and LoVo cell lines.A549, LoVo, CEM and Hep-G2 cell lines were selected to detect the activities of compound...