环境胁迫对珊瑚共附生真菌Aspergillus ochraceus LCJ11-102次级代谢产物的影响

Effects of environmental stress on secondary metabolites of Aspergillus ochraceus LCJ11-102 associated with the coral Dichotella gemmacea

摘要:

摘要：【目的】研究环境胁迫对珊瑚共附生真菌Aspergillus ochraceus的次生代谢的影响，寻找活性代谢产物。【方法】采用仿生培养和高盐胁迫两种不同的发酵条件对菌株进行液体大发酵，运用HPLC指纹图谱考察发酵产物的化学多样性，采用硅胶柱色谱、凝胶柱色谱和HPLC等方法对发酵产物进行分离、纯化，运用波谱和Mosher方法鉴定化合物的结构。【结果】发现菌株在两种环境胁迫条件下产生了不同的次生代谢产物，从中分别鉴定了4个（1–4）和1个主要化合物5：R(–)- mellein (1)、(5,6-trans, 8,9-threo-)-9-chloro-8-hydroxy-8,9-deoxyaspyrone (2)、(5,6-erythro-, 8,9-threo-)-9-chloro-8-hydroxy-8,9- deoxyasperlactone (3)、(5S,6R,9S)-dihydroaspyrone (4)和R(+)-semi-vioxanthin (5)。【结论】环境胁迫可以诱导海洋微生物产生不同的次生代谢产物，仿生培养是从海洋微生物中获得氯代产物的有效途径。

Abstract:

Abstract: [Objective] To explore the secondary metabolites of fungus Aspergillus ochraceus LCJ11-102 associated with the coral Dichotella gemmacea under environmental stress and to obtain characteristic compounds with biological activities. [Methods] A nutrient-deprived culture medium (biomimetic culture) and a high salt culture medium were used for fermentation. Fingerprints of HPLC of the fermentation broth were used to investigate the diversity of secondary metabolites. Compounds were isolated by column chromatography on silica gel, Sephadex LH-20, and preparative HPLC. Their structures were identified by spectroscopic analyses and the modified Mosher’s method. [Results] Different secondary metabolites were produced by A. ochraceus LCJ11-102 under two different culture conditions. (R)-mellein (1), (5,6-trans, 8,9-threo-)-9-chloro-8-hydroxy-8,9-deoxyaspyrone (2), (5,6-erythro-, 8,9-threo-)-9-chloro-8-hydroxy-8,9-deoxyasperlactone (3), and (5S,6R,9S)-dihydroaspyrone (4) were identified from the biomimetic cultures, and R(+)-semi-vioxanthin (5) was identified from the high salt cultures, respectively. [Conclusion] Environmental stress obviously induces microbes to produce different secondary metabolites. And biomimetic culture is an effective approach to obtain active chloro compounds from marine microorganisms.