College of Grassland Science, Shanxi Agricultural University, Taigu, China.
College of Grassland Science and Technology, China Agricultural University, Beijing, China.
Pol J Microbiol. 2020 Sep;69(3):339-347. doi: 10.33073/pjm-2020-037. Epub 2020 Sep 8.
Ligninolytic bacteria degrading lignin were isolates and identified, and their biodegradation mechanism of alkaline-lignin was investigated. Four strains with lignin degradation capability were screened and identified from the soil, straw, and silage based on their decolorizing capacity of aniline blue and colony size on alkaline-lignin medium. The degradation ratio of BY5, LN2, LN4, and CL32 have been assayed using alkaline-lignin as the unique carbon source. Further, the Lip (lignin peroxidase) and Mnp (manganese peroxidase) activities of strains were investigated. Lip activity of LN4 was highest after 72 h of incubation and reached 7151.7 U · l. Mnp activity of CL32 was highest after 48 h and reached 12533 U · l. The analysis of alkaline-lignin degradation products by GC-MS revealed that the strains screened could utilize aromatic esters compounds such as dibutyl phthalate (DBP), and decomposite monocyclic aromatic compounds through the DBP aerobic metabolic pathway. The results indicate that BY5, LN2, LN4, and CL32 have high potential to degrade alkaline-lignin, and might utilize aromatic compounds by DBP aerobic metabolic pathway in the process of lignin degradation.
从土壤、秸秆和青贮饲料中筛选到 4 株具有木质素降解能力的菌株，根据在碱性木质素培养基上的菌落大小和对苯胺蓝的脱色能力进行分离和鉴定。以碱性木质素为唯一碳源，测定了 BY5、LN2、LN4 和 CL32 的降解率。进一步研究了菌株的 Lip（木质素过氧化物酶）和 Mnp（锰过氧化物酶）活性。LN4 在孵育 72 h 后 Lip 活性最高，达到 7151.7 U·l。CL32 在 48 h 后 Mnp 活性最高，达到 12533 U·l。GC-MS 分析碱性木质素降解产物表明，筛选到的菌株可通过邻苯二甲酸二丁酯（DBP）有氧代谢途径利用芳香酯类化合物如邻苯二甲酸二丁酯（DBP），并通过 DBP 有氧代谢途径分解单环芳香族化合物。结果表明，BY5、LN2、LN4 和 CL32 具有较高的碱性木质素降解潜力，在木质素降解过程中可能通过 DBP 有氧代谢途径利用芳香族化合物。
