菌物学报2025，Vol.44Issue(11)：210-222,13.DOI:10.13346/j.mycosystema.250106
一株分离自西藏雅江雪牛瘤胃的纤维素降解菌库氏毕赤酵母的降解特性
Degradation characteristics of a cellulose-degrading fungus Pichia kudriavzevii isolated from the rumen of Yajiang snow cattle in Xizang
摘要
Abstract
To augment feed resources and efficiently utilize straw,cellulose-degrading fungal strains were isolated from the rumen of Yajiang snow cattle in Xizang using a carboxymethyl cellulose selective medium.An investigation of their enzyme-producing properties and capabilities of degrading straw was carried out.The result was that six strains capable of degrading filter paper strips were discovered,of which one strain(XZ6)was classified as Pichia kudriavzevii.Single-factor optimization of enzyme production conditions showed that the optimal conditions for xylanase production by this strain were temperature of 33 ℃,cultivation time of 18 h,shaker speed of 240 r/min,and inoculation volume of 1%(v/v).Under these conditions,xylanase activity peaked at 11.55 U/mL,which was 12 times higher than that before optimization.The β-glucanase activity peaked at 1.82 U/mL,a 7-fold increase over that before optimization;the β-mannanase activity reached a maximum of 2.07 U/mL,a 3-fold increase in the activity.Whole genome sequencing indicated that this strain included 408 glycoside hydrolase genes and 352 glycosyl transferase genes.The fermentation of highland barley straw and corn straw using the crude enzyme solution of strain XZ6 markedly diminished the levels of crude fiber,neutral detergent fiber,and acid detergent fiber in both types of straw.Strain XZ6 possesses the capacity to degrade straw fiber.关键词
雅江雪牛/库氏毕赤酵母/产酶条件优化/全基因组测序/纤维降解能力Key words
Yajiang snow cattle/Pichia kudriavzevii/optimization of enzyme-producing conditions/whole genome sequencing/cellulose degradation ability引用本文复制引用
张蓓宁,孔庆辉,王志佳,刘丰慧,刘锁珠,谭占坤,商振达..一株分离自西藏雅江雪牛瘤胃的纤维素降解菌库氏毕赤酵母的降解特性[J].菌物学报,2025,44(11):210-222,13.基金项目
西藏农牧学院研究生创新项目(YJS2023-19) （YJS2023-19）
西藏农牧学院学科建设项目(YJSXK2025-17)This work was supported by the Xizang Agricultural and Animal Husbandry College Graduate Innovation Project(YJS2023-19)and the Xizang Agricultural and Animal Husbandry College Discipline Construction Project(YJSXK2025-17). （YJSXK2025-17）
