红海榄根际土壤来源的泡盛曲霉（Aspergillus awamori）F12及其代谢产物的抗菌活性分析

Antibacterial activity of secondary metabolites from Aspergillus awamori F12 isolated from rhizospheric soil of Rhizophora stylosa Griff

摘要:

摘要：【目的】鉴定一株来自于红海榄根际土壤并具有分泌抑菌活性代谢产物的真菌菌株F12，并从其发酵液乙酸乙酯浸膏中分离抑菌活性成分。【方法】通过形态学观察以及ITS序列分析方法对菌株F12进行鉴定；利用色谱技术分离发酵液乙酸乙酯浸膏中的次生代谢产物，根据化合物的质谱、氢谱、碳谱以及理化性质确定其结构，并检测它们对细菌生长的抑制作用。【结果】菌株F12被鉴定为Aspergillus awamori strain F12；从其发酵液乙酸乙酯浸膏中分离到3种化合物：1,4-二甲氧基苯（1）、大黄素（2）和3,6-二苯甲基哌嗪-2,5-二酮（3），其中化合物1属于在本属真菌中首次报道。化合物2对金黄色葡萄球菌和枯草芽孢杆菌的生长具有明显的抑制作用，最低抑菌浓度（MIC）分别为16ng/L和32ng/L，化合物1和3对上述菌株的生长无明显的抑制活性。【结论】首次发现从红海榄根际土壤中分离到的泡盛曲霉（Aspergillus awamori）菌株F12具有合成1,4-二甲氧基苯和大黄素的能力，其中后者对微生物的生长具有明显的抑制作用。

Abstract:

Abstract: [Objective] To identify Aspergillus awamori strain F12 isolated from rhizospheric soil of Rhizophora stylosa Griff and to characterize antibacterial compounds from the ethyl acetate extracts of its fermentation broth. [Methods] Strain F12 was identified based on its morphological characters and internal transcribed spacer (ITS) sequence. Its secondary metabolites were purified by chromatography, and elucidated by mass spectroscopy, 1H-NMR, 13C-NMR and physicochemical characters. The antibacterial activities of these compounds were tested against Staphyloccocus aureus and Bacillus subtilis. [Results] Strain F12 was identified as Aspergillus awamori. Three compounds, including 1,4-dimethoxybenzene (1), emodin (2) and 3, 6-dibenzylpiperazine-2, 5-dione (3), were purified and elucidated from the ethyl acetate extracts of fermentation broth, among which compound 1 was first reported for the genus of Aspergillus. Compound 2 suppressed the growth of Staphyloccocus aureus and Bacillus subtilis with MIC values of 16 μg/mL and 32 μg/mL respectively, while the other two compounds have no effects on these bacteria. [Conclusion] Aspergillus awamori strain F12 isolated from rhizospheric soil of Rhizophora stylosa Griff can produce 1, 4-dimethoxybenzene and emodin, among which the latter can suppress the growth of bacteria apparently.