摘要
以青藏高原冷地早熟禾草地土壤为样品,筛选低温纤维素降解菌株。采用刚果红染色法(水解圈法)和3,5-二硝基水杨酸(DNS)法进行菌株筛选与酶学特性研究,结合形态学与分子生物学方法对其进行鉴定。筛选出一株低温纤维素降解菌株(LD19),经鉴定为钉斑链霉菌(Streptomyces clavifer),同时该菌还具有降解半纤维素的能力。该菌产纤维素酶的最适温度为40℃,最适pH值为6,在30~70℃、pH值4~10时相对酶活力较稳定,Zn^(2+)对酶有抑制作用。该菌产半纤维素酶的最适温度为50℃,最适pH值为6,在30~40℃、pH值4~9时相对酶活力较稳定,Cu^(2+)等对该酶有促进作用。该菌株在培养102 h后两种酶的相对酶活力均达到最高值。菌株LD19可以同时分泌低温纤维素酶和半纤维素酶,在饲用酶制剂的应用中具有较大潜力。
To screen cold-adapted cellulose-degrading strains from the Kentucky bluegrass meadow soil on the Qinghai-Tibet Plateau.Xylanase-hydrolyzing ring method and 3,5-dinitrosalicylic acid(DNS)method were used to screen strains,and test enzymatic characteristics respectively.Strains were identified by morphology and molecular biological identification.A cold-adapted cellulose-degrading strain(LD19)was identified asStreptomyces clavifer,which also has the ability to degrade hemicellulose.The optimum reaction temperature and pH value of the cellulase was 40℃and 6 respectively.The cellulase enzyme activity is relative stable under 30-70℃or pH 4-10.The cellulase activity of LD19 was significantly reduced by Zn^(2+).Meanwhile,the optimum reaction temperature and pH value of the hemicellulose was 50℃and 6.The hemicellulose enzyme activity is relative stable under 30-40℃or pH 4-9.The hemicellulose activity of LD19 was significantly enhanced by Cu^(2+).During fermentation culture,both cellulase activity and hemicellulose activity of LD19 reached the optimum activity after 102 h.A coldadapted cellulose-degrading strain LD19 was screened and identified from the Kentucky bluegrass meadow soil on the Qinghai-Tibet Plateau,which also has hemicellulose activity.The stain has potential value in feed additive.
作者
曹慧
任世威
张腾月
秦亚宁
张兰
杨佳萌
张朋振
CAO Hui;REN Shiwei;ZHANG Tengyue;QIN Ya’ning;ZHANG Lan;YANG Jiameng;ZHANG Pengzhen(College of Animal Science and Technology,Henan University of Science and Technology,Henan Luoyang 471000,China;College of Coastal Agriculture Sciences,Guangdong Ocean University,Guangdong Zhanjiang 524088,China;Animal Nutrition Institute,Sichuan Agricultural University,Sichuan Chengdu 611130,China;College of Animal and Veterinary Sciences,Southwest Minzu University,Sichuan Chengdu 610041,China)
出处
《饲料工业》
CAS
北大核心
2021年第8期36-41,共6页
Feed Industry
基金
河南科技大学博士科研启动资金[13480077]
青海省重点研发计划[2017-NK-153、2019-NK-173、2019-SF-149]。
关键词
低温纤维素酶
青藏高原
酶学特性
半纤维素酶
钉斑链霉菌
low temperature cellulase
Qinghai-Tibet Plateau
enzymology characteristics
hemicellulase
Streptomyces clavifer
作者简介
曹慧,博士,研究方向为功能性微生物开发。
