Long Junqiao, Wang Xueli, Qiu Shuyi, Zhou Wei, Zhou Shaoqi, Shen Kaiwei, Xie Lili, Ma Xiao, Zhang Xuyi
Guizhou Province Key Laboratory of Fermentation Engineering and Biopharmacy, Guizhou University, Guiyang, China.
College of Liquor and Food Engineering, Guizhou University, Guiyang, China.
Front Microbiol. 2024 Mar 14;15:1356903. doi: 10.3389/fmicb.2024.1356903. eCollection 2024.
Spent mushroom substrate (SMS) is a solid waste in agricultural production that contains abundant lignocellulosic fibers. The indiscriminate disposal of SMS will lead to significant resource waste and pollution of the surrounding environment.The isolation and screening of microorganisms with high cellulase degradation capacity is the key to improving SMS utilization.
The cellulose-degrading microbial consortiums were constructed through antagonism and enzyme activity test. The effect of microbial consortiums on lignocellulose degradation was systematically evaluated by SMS liquid fermentation experiments.
In this study, four strains of cellulose-degrading bacteria were screened, and F16, F, and F7 were identified as , PX1 identified as . At the same time, two groups of cellulose efficient degrading microbial consortiums (PX1 + F7 and F16 + F) were successfully constructed. When SMS was used as the sole carbon source, their carboxymethyl cellulase (CMCase) activities were 225.16 and 156.63 U/mL, respectively, and the filter paper enzyme (FPase) activities were 1.91 and 1.64 U/mL, respectively. PX1 + F7 had the highest degradation rate of hemicellulose and lignin, reaching 52.96% and 52.13%, respectively, and the degradation rate of F16 + F was as high as 56.30%. Field emission scanning electron microscopy (FESEM) analysis showed that the surface microstructure of SMS changed significantly after microbial consortiums treatment, and the change of absorption peak in Fourier transform infrared spectroscopy (FTIR) and the increase of crystallinity in X-ray diffraction (XRD) confirmed that the microbial consortiums had an actual degradation effect on SMS. The results showed that PX1 + F7 and F16 + F could effectively secrete cellulase and degrade cellulose, which had practical significance for the degradation of SMS.
In this study, the constructed PX1 + F7 and F16 + F strains can effectively secrete cellulase and degrade cellulose, which holds practical significance in the degradation of SMS. The results can provide technical support for treating high-cellulose solid waste and for the comprehensive utilization of biomass resources.
菌糠是农业生产中的一种固体废弃物，含有丰富的木质纤维素纤维。菌糠的随意处置会导致大量资源浪费和对周边环境的污染。分离和筛选具有高纤维素降解能力的微生物是提高菌糠利用率的关键。
通过拮抗和酶活性试验构建纤维素降解微生物菌群。通过菌糠液体发酵实验系统评估微生物菌群对木质纤维素降解的影响。
本研究筛选出4株纤维素降解菌，鉴定F16、F和F7为 ，PX1鉴定为 。同时，成功构建了两组纤维素高效降解微生物菌群（PX1 + F7和F16 + F）。以菌糠为唯一碳源时，它们的羧甲基纤维素酶（CMCase）活性分别为225.16和156.63 U/mL，滤纸酶（FPase）活性分别为1.91和1.64 U/mL。PX1 + F7的半纤维素和木质素降解率最高，分别达到52.96%和52.13%，F16 + F的降解率高达56.30%。场发射扫描电子显微镜（FESEM）分析表明，微生物菌群处理后菌糠的表面微观结构发生显著变化，傅里叶变换红外光谱（FTIR）吸收峰的变化以及X射线衍射（XRD）结晶度的增加证实微生物菌群对菌糠有实际降解作用。结果表明，PX1 + F7和F16 + F能有效分泌纤维素酶并降解纤维素，这对菌糠的降解具有实际意义。
本研究构建的PX1 + F7和F16 + F菌株能有效分泌纤维素酶并降解纤维素，在菌糠降解方面具有实际意义。研究结果可为处理高纤维素固体废弃物及生物质资源综合利用提供技术支持。
