高效木质纤维素分解菌的筛选及复合菌系降解秸秆效果研究  

Screening of high-efficiency lignocellulosic degrading bacteria and study on the degradation effect of straw by complex microbial systems

作　　者：王子苑 吉玉玉 舒健虹 陈光吉 张蓉 王小利 WANG Ziyuan;JI Yuyu;SHU Jianhong;CHEN Guangji;ZHANG Rong;WANG Xiaoli(Guizhou Institute of Prataculture,Guiyang,Guizhou Province 550006,China)

机构地区：[1]贵州省草业研究所,贵州贵阳550006

出　　处：《中国饲料》2024年第15期19-26,共8页China Feed

基　　金：黔科合支撑“贵州优质饲草秸秆资源利用关键技术研究与示范”([2021]一般179);黔科合基础“纤维素降解菌与产阿魏酸酯酶乳酸菌协同降解玉米秸秆木质纤维素机制研究”(ZK[2024]一般537);黔科合成果“酱酒酒糟及农作物秸秆饲料化技术集成推广应用”([2022]重点005);黔科合服企“贵州草地资源管理与高效利用创新能力建设”([2022]004)。

摘　　要：为分离、筛选并构建高效降解玉米秸秆木质纤维素的复合菌系,本试验以羧甲基纤维素钠(CMC-Na)为碳源,采用刚果红平板初筛,内切葡聚糖酶(CMCase)、滤纸酶(FPA)和木质素过氧化物酶(Lip)活性复筛,从腐烂的水稻秸秆、森林腐殖质和腐殖土中筛选获得产酶能力较高的5株单一菌株,编号为K3、P4、H7、R18和C25,利用16S rDNA基因序列鉴定分别为克雷伯氏菌(Klebsiella sp.,K3)、菠萝泛菌(Pantoea ananatis,P4)、草螺菌(Herbaspirillum seropedicae,H7)、解鸟氨酸拉乌尔菌(Raoultella ornithinolytica,R18)和费氏柠檬酸杆菌(Citrobacter freundii,C25)。通过对无拮抗作用的菌株进行等比复配构建了8组复合菌系,经酶活性测定最终将复合菌系B(P4,R18)、C(R18,C25)、F(K3,R18,C25)、G(P4,R18,C25)和H(K3,P4,R18,C25)作为优势复合菌系,用于玉米秸秆降解效果研究。结果表明:复合菌系的酶活性高于单一菌株,复合菌系F、G和H对秸秆降解效果较好,处理26 d后的秸秆失重率分别达到32.96%、36.24%和46.41%,其中复合菌系H对秸秆纤维素、半纤维素和木质素降解率分别为28.02%、36.31%和25.16%,对秸秆的木质纤维素降解效果最佳,具有较好的应用潜力。In order to isolate,screen and construct complex microbial systems that could degrade lignocellulose for corn straw efficiently,this experiment used sodium carboxymethyl cellulose(CMC-Na)as carbon source.The strains were screened by Congo red plate dilution method,and the carboxymethyl cellulose activity(CMCase),filter paper enzyme(FPA)and lignin peroxidase(Lip)were determined for further screening.Five strains with high enzyme production capacity were screened from rotten rice straw,forest humus and humus soil,of which K3 identified by 16S rDNA gene sequence as Klebsiella sp.,P4 as Pantoea ananatis,H7 as Herbaspirillum seropedicae,R18 as Raoultella ornithinolytica,and C25 as Citrobacter freundii.According to the antagonistic test,eight groups of complex microbial systems were constructed.Based on enzyme activity determination,the complex microbial systems B(P4,R18),C(R18,C25),F(K3,R18,C25),G(P4,R18,C25)and H(K3,P4,R18,C25)were finally selected as the dominant complex microbial systems for study on degradation effect of corn straw.The results showed that the enzyme activity of the complex microbial systems was higher than that of the single strain,and the complex microbial systems F,G and H had a better degradation effect on the corn straw.After 26 days of treatment with them,the weight loss rate of the corn straw reached 32.96%,36.24%and 46.41%,respectively.The degradation rates of cellulose,hemicellulose and lignin of corn straw by complex microbial system H were 28.02%,36.31%and 25.16%,respectively.The complex microbial system H had the best degradation effect on lignocellulose degradation of corn straw and had good application potential.

关 键 词：木质纤维素 细菌 筛选 玉米秸秆 降解 

分 类 号：S816.3[农业科学—饲料科学]