Comamonas serinivorans C35木质素降解性能

Lignin degradation by Comamonas serinivorans C35

摘要:

【目的】探讨菌株Comamonas serinivorans C35降解木质素的能力。【方法】测定Comamonas serinivorans C35在木质素培养基中的生长趋势、化学需氧量的去除、木质素降解率、脱色率和相关酶的分泌。分别采用扫描电子显微镜和傅里叶变换红外光谱分析仪检测木质素降解前后的外观结构和化学键的变化。【结果】Comamonas serinivorans C35能够在木质素培养基上生长，在培养7 d后，化学需氧量去除率为44.4%，木质素降解率和脱色率分别为43.57%和42.26%。Comamonas serinivorans C35能够分泌木质素过氧化物酶、锰过氧化物酶和漆酶，粗酶液酶活分别能达到648.4、177.8和70.1 U/L。Comamonas serinivorans C35可以使木质素解聚且对其苯环结构、醚键以及C=O键等具有明显的破坏作用。【结论】 Comamonas serinivorans C35可以降解木质素，在木质素的生物转化中具有潜在的应用价值。

Abstract:

[Objective] The aim of this study was to study the degradation of lignin by Comamonas serinivorans C35. [Methods] Comamonas serinivorans C35 growth was measured. Chemical oxygen demand (COD) reduction was investigated. Lignin degradation and decolorization rates were conducted. In addition, secretion of ligninolytic enzymes were investigated by using lignin mineral salt medium. The changes in lignin structural appearance and the chemical bonds of it before and after degradation were assessed by scanning electron microscope (SEM) and fourier transform infrared spectroscopy techniques (FTIR), respectively. [Results] The ability of Comamonas serinivorans C35 in the presence of lignin as a sole carbon source with 44.4% reduction in COD value after 7 days of incubation. The degradation and decolorization removal reached 43.57% and 42.26%, respectively. It was shown that the maximal enzyme activities of lignin peroxidase, manganese peroxidase and laccase of the studied isolate recorded 648.4, 177.8 and 70.1 U/L, respectively throughout the incubation course. SEM revealed the depolymerization of lignin into smaller pieces and FTIR confirmed the benzene ring structure, C–O–C and C=O bonds of lignin were broken down. [Conclusion] The results of this study indicate that Comamonas serinivorans C35 potentiates its ability not only to utilize lignin as a sole carbon source but also its applicable value in lignin bioconversion.