海洋真菌Aspergillus niger XJJ-3中萘并吡喃酮类化合物结构及生物活性

Structures and activities of naphthopyrones from marine fungus Aspergillus niger XJJ-3

摘要:

【背景】萘并吡喃酮类化合物生物活性多样，是真菌Aspergillus niger中特征次生代谢产物。【目的】研究分离自海洋滩涂土壤的真菌Aspergillus niger XJJ-3中萘并吡喃酮类化合物结构及其抗菌和卤虫致死活性。【方法】以TLC分析为导向，综合运用多种色谱和光谱方法分离和鉴定萘并吡喃酮类化合物。采用微量稀释法测试化合物的抗菌和卤虫致死活性。【结果】从真菌A. niger大米发酵产物中共分离得到6个萘并吡喃酮类化合物，鉴定为Rubrofusarin B (1)、Flavasperone (2)、Aurasperone A (3)、Asperpyrones C (4)、Asperpyrones B (5)和Fonsecinone A (6)。抗菌活性实验结果表明，化合物1?6对致病菌S. aureus ATCC33591、29213、E. faecium ATCC35667和V. parahemolyticus表现出不同程度的抑制活性，其中化合物2和4对S. aureus ATCC33591表现出较强抑制活性(MIC分别为43.7 μmol/L和21.9 μmol/L)，化合物3对E. faecium ATCC35667抑制活性较强(MIC为21.9 μmol/L)。卤虫致死活性实验结果表明，化合物1?6均表现出一定的卤虫致死活性，其中化合物2和3活性显著(LD50分别为35.0 μmol/L和8.8 μmol/L)。【结论】菌株XJJ-3可产生结构丰富的萘并吡喃酮类化合物，化合物1?6存在不同程度的抗菌和卤虫致死活性，该研究可为抗菌和细胞毒类药物的研发提供参考。

关键词:海洋真菌，黑曲霉，萘并吡喃酮，抗菌活性，卤虫致死活性

Abstract:

[Background] Naphthopyrones possess various bioactivities that are characteristic secondary metabolites of the fungus Aspergillus niger. [Objective] To illuminate the structures and activities of naphthopyrones from fungus A. niger isolated from mud flat. [Methods] Guided by TLC analysis, we used combined chromatographic and spectrographic techniques to identify naphthopyrones. The activities against pathogen bacteria and Artemia salina were tested by micro-dilution method. [Results] Six naphthopyrones: Rubrofusarin B (1), Flavasperone (2), Aurasperone A (3), Asperpyrones C (4), Asperpyrones B (5) and Fonsecinone A (6) were isolated from A. niger. In bioassays, compounds 1 through 6 showed different levels of antibacterial activities against pathogen bacteria. Flavasperone (2) and Asperpyrones C (4) showed potent antibacterial activities against S. aureus ATCC33591 with MIC values 43.7 and 21.9 μmol/L, respectively. Aurasperone A (3) exhibited significant activities against E. faecium ATCC35667 with MIC values 21.9 μmol/L. Compounds 1 through 6 displayed toxicity on brine shrimps larvae, the LD50 values of Flavasperone (2) and Aurasperone A (3) were 35.0 and 8.8 μmol/L, respectively. [Conclusion] Diverse naphthopyrones were produced by strain XJJ-3. Compounds 1 through 6 showed different levels of activities against pathogen bacteria and Artemia salina. This study may provide reference for the development of antibacterial and cytotoxic drugs.

Key words:Marine fungus, Aspergillus niger, Naphthopyrones, Antibacterial activity, Brine shrimp lethality