中国南海部分深海沉积物真菌多样性及其抗菌活性

Diversity and antimicrobial activity of fungi isolated from deep-sea sediments in South China Sea

摘要:

[目的] 从南海4个站位的深海沉积物中分离真菌，揭示其多样性并测定抗菌活性。[方法] 使用4种培养方法和8种培养基，从12个深海沉积物样本中分离培养真菌，通过菌落形态观察和ITS序列系统发育分析进行鉴定。采用滤纸片扩散法和生长速率法分别测试真菌小量发酵液粗浸膏的抗细菌和抗真菌活性。[结果] 共分离到125株纯培养真菌，基于形态和ITS序列分析，排重后得到18个种类型，这些真菌可以划分到12个属，大多数属于子囊菌门（Ascomycota），只有2株属于担子菌门（Basidiomycota）。4个站位可培养真菌多样性具有差异性。抑菌活性筛选显示，大多数真菌具有较好的抑菌活性；链格孢属（Alternaria）、青霉属（Penicillium）、匐柄霉属（Stemphylium）这几个属的真菌表现出对多种指示细菌有抑制作用，尤其是Alternaria tenuissima DN09、Alternaria alternata DN14和Penicillium chrysogenum DN16对G⁺和G^-细菌均表现出抑制作用。[结论] 本研究揭示了南海深海沉积物可培养真菌多样性和抑菌活性，为进一步利用深海沉积物来源真菌奠定了基础。

Abstract:

[Objective] To reveal the diversity and antimicrobial activity of culturable fungi from the deep-sea sediments in 4 different sites in South China Sea.[Methods] We used 4 different methods and 8 different media to study the culturable fungal diversity in 12 deep-sea sediments samples. We identified fungal isolates by colonial morphology observation and ITS-based phylogenetic analysis. We used disc diffusion and growth rate methods to test antibacterial and antifungal activities.[Results] A total of 125 fungi were isolated from the sediments. Based on the ITS sequence analysis and morphological characteristics, the isolates were grouped to 18 fungal species and 12 genera within 2 phyla. Most fungi belong to Ascomycota and only 2 isolates belong to Basidiomycota. The culturable fungal diversity was different among the 4 locations. Most of the fungal isolates exhibited antimicrobial activity. The genera Alternaria, Penicillium and Stemphylium displayed antibacterial activity against more than one indicator. Particularly, Alternaria tenuissima DN09, Alternaria alternata DN14 and Penicillium chrysogenum DN16 displayed activity against both Gram-positive and Gram-negative bacteria.[Conclusion] Higher diversity and antimicrobial activity of the culturable fungi isolated from deep-sea sediments in South China Sea provide the potential application of these fungi.