仿刺参共附生放线菌Brevibacterium sp.中的环二肽成分的分离和鉴定

Cyclic dipeptides in actinomycete Brevibacterium sp. associated with sea cucumber Apostichopus japonicus Selenka: isolation and identification

目的对仿刺参共附生放线菌Brevibacterium sp.的次生代谢产物进行研究。方法运用硅胶柱色谱、Seph-adex LH-20凝胶柱色谱、高效液相色谱(HPLC)等现代色谱技术对放线菌的乙酸乙酯提取物进行分离纯化,在核磁共振(NMR)、质谱(MS)等现代波谱技术及与文献比对的基础上对其结构进行鉴定。结果共分离得到7个环二肽类化合物,分别鉴定为:环-(L-脯氨酸-L-苯丙氨酸)(1)、环-(L-脯氨酸-L-甲硫氨酸)(2)、环-(L-脯氨酸-L-酪氨酸)(3)、环-(L-脯氨酸-L-缬氨酸)(4)、环-(L-脯氨酸-L-脯氨酸)(5)、环(L-缬氨酸-甘氨酸)(6)、环-(L-脯氨酸-L-亮氨酸)(7)。结论本研究是对仿刺参共附生微生物次生代谢产物研究的首次报道,这7个化合物均为首次从放线菌Brevi-bacterium sp.中分离得到。

Objective To investigate the secondary metabolites of actinomycete Brevibacteriurn sp. associated with the sea cucumber Apostichopusjaponicus Selenka. Methods The ethyl acetate extract of the actinomycete was purified by repeated column chromatography on silica gel, Sephadex LH-20, and high-performance liquid chromatography （HPLC） to obtain pure compounds~ and the compound structures were elucidated by spectroscopic analysis （nuclear magnetic resonance, NMR; mass spectrometry, MS） and the results were compared with the previously reported data. Results Seven compounds were isolated： eyclo-（L-Pro-L-Phe） （1）, eyclo-（L Pro-L-Met） （2）, cyclo-（L-Pro-L-Tyr） （3）, cyclo-（L-Pro-L-Val） （4）, cyclo-（L-Pro-L- Pro） （5）, cyelo-（L-Val-Gly） （6）, and cyclo-（L-Pro-L-Leu） （7）. Conclusion This is the first report on the secondary metabolites of microorganisms associated with the sea cucumber Apostichopus japonicus Selenka, and all the seven compounds have been reported from the actinomycete Brevibacterium sp. for the first time.