深海真菌Chaetomium sp.CS1的木质素降解特征  

Lignin-degradation characteristics of deep-sea fungus Chaetomium sp.CS1

作　　者：庄培文 张恺 郑平 凌铭煌 张玉苍 骆祝华 ZHUANG Peiwen;ZHANG Kai;ZHENG Ping;LING Minghuang;ZHANG Yucang;LUO Zhuhua(College of Ocean Food and Biological Engineering,Jimei University,Xiamen 361021,Fujian,China;Key Laboratory of Marine Biogenetic Resource,Third Institute of Oceanography,Ministry of Natural Resources,Xiamen 361005,Fujian,China)

机构地区：[1]集美大学海洋食品与生物工程学院,福建厦门361021 [2]自然资源部第三海洋研究所海洋生物遗传资源重点实验室,福建厦门361005

出　　处：《菌物学报》2023年第12期2442-2453,共12页Mycosystema

摘　　要：本研究旨在从深海环境中分离、筛选木质素高效降解真菌并分析其对木质素的降解过程。通过对西太平洋深海沉积物和海水样品中可培养真菌的分离筛选,成功获得了一株能够以木质素为唯一碳源生长的真菌菌株CS1,通过ITS基因序列鉴定,确定其为毛壳菌属Chaetomium sp.真菌。菌株CS1以碱性木质素为唯一碳源培养14 d,木质素降解率达到64%,同时菌株孢子能够在较广的pH范围内萌发生长(pH 4.0–9.0)。该菌株具有分泌多种胞外木质素降解酶的潜力,能够使苯胺蓝褪色并使愈创木酚产生棕红色氧化圈。红外光谱(FTIR)分析显示,菌株CS1对木质素的降解主要是对木质素的芳香族骨架、β-O-4的C-O键以及β或γ位的O-H造成破坏。此外,菌株CS1可在烟草秸秆表面形成生物膜以实现木质素的降解与转化,而GC-MS分析结果表明该菌株能够促进烟草秸秆中烟碱类活性物质的释放,并将木质素中的芳香族聚合物转化为二甲苯等石化工业基础原料。本研究结果揭示了海洋真菌对烟草秸秆类木质纤维素的降解潜力,为木质素废弃物的资源化利用提供了优良的菌种资源。This study aims to isolate and screen lignin-degrading fungi from the deep-sea environment and analyze their degradation process of lignin.Cultivable fungi were sampled from deep-sea sediment and seawater in the West Pacific,and a strain CS1 capable of growing on lignin as the sole carbon source was successfully obtained.Based on ITS gene sequence identification,the fungus was identified as Chaetomium sp.After 14 days of cultivation with alkaline lignin as the sole carbon source,the lignin degradation rate of the fungus reached 64%,and the fungal spores could germinate and the mycelia could grow within a wide range of pH values(pH 4.0–9.0).The fungus has the potential to secrete various extracellular lignin-degrading enzymes which can fade aniline blue and produce brown-red oxidation circles in guaiacol.Fourier transform infrared spectroscopy(FTIR)analysis showed that the degradation of lignin by the fungus CS1 was mainly due to the destruction of the aromatic skeleton of lignin,the C-O bond ofβ-O-4,and the O-H ofβorγpositions.Further research found that strain CS1 can form a biofilm on the surface of tobacco straw to achieve the degradation and transformation of lignin.GC-MS analysis results showed that this fungus promoted the release of nicotine-like active substances from tobacco straw and transformed aromatic polymer of lignin to xylene and other petrochemical industry basic raw materials.The results reveal the potential of marine fungi on degradation of lignocellulose in tobacco straw and provide excellent fungal strains for resource utilization of lignin waste.

关 键 词：木质素 毛壳菌 降解 生物转化 

分 类 号：Q939.9[生物学—微生物学]