Page 159 - 《精细化工》2020年第8期

第 37 卷第 8 期 精 细 化 工 Vol.37, No.8
202 0 年 8 月 FINE CHEMICALS Aug. 2020

生物工程
产纤维素酶放线菌的筛选鉴定及其

对玉米秸秆的降解

刘晓飞，宋 洁，马京求，侯 艳，郑志辉

（哈尔滨商业大学 食品工程学院，黑龙江 哈尔滨 150076）

摘要：从寒地黑土中筛选得到一株对纤维素具有降解能力的菌株，观察该菌株的形态特征并对其进行分子生物
学鉴定。采用响应曲面法对该菌株降解玉米秸秆的条件进行优化，并对玉米秸秆降解前后的结构变化、主要成
分变化进行观察和测定。结果表明：该菌编号为 GS-4-21，其透明圈与菌落直径的比值（D/d）为 5.54±0.20，滤
纸酶活、纤维素外切酶活、纤维素内切酶活和 β-糖苷酶酶活分别为 11.94±0.51、12.07±0.43、32.94±0.83 和
30.87±1.04 U/mL。经鉴定菌株 GS-4-21 属于链霉菌属。当以体积分数 3%接种至 pH 为 6 的发酵培养基中，28 ℃、
160 r/min 发酵 5 d 时，玉米秸秆的降解率可达 23.54%。SEM 结果表明：菌株 GS-4-21 具有较好的纤维素降解能
力。玉米秸秆中纤维素、半纤维素、木质素的降解率分别为 30.33%、31.95%、18.91%。
关键词：寒地黑土；放线菌；玉米秸秆；纤维素酶；响应曲面优化；生物工程
中图分类号：TS201.3 文献标识码：A 文章编号：1003-5214 (2020) 08-1657-09

Screening and identification of a cellulase-producing actinomycete
and its degradation of corn straw

LIU Xiaofei, SONG Jie, MA Jingqiu, HOU Yan, ZHENG Zhihui
（College of Food Science and Engineering, Harbin University of Commerce, Harbin 150076, Heilongjiang, China）

Abstract: A strain with the ability to degrade cellulose was selected from the black soil in the cold region.
The morphological characteristics of the strain were observed and molecular biological identification was
carried out. The response surface method was used to optimize the conditions of corn straw degradation by
the strain, and the changes of structure and main component of corn straw before and after degradation were
observed and determined. The results showed that the strain number was GS-4-21, and the ratio of the
transparent circle to colony diameter (D/d) was 5.54±0.20. The enzyme activities of filter paper,
exocellulase, endocellulase and β-glycosidase were 11.94±0.51, 12.07±0.43, 32.94±0.83 and 30.87±
1.04 U/mL, respectively. The identified strain GS-4-21 belonged to the genus Streptomyces. The
degradation rate of corn straw reached 23.54% when the inoculation amount was 3% (volume fraction),
initial pH of the culture medium was 6 , fermentation time was 5 d, fermentation temperature was 28 ℃,
and rotating speed was 160 r/min. SEM results demonstrated that strain GS-4-21 had better cellulose
degradation ability. The degradation rates of cellulose, hemicellulose and lignin in corn straw were 30.33%,
31.95% and 18.91%, respectively.
Key words: black soil in the cold region; actinomycetes; corn straw; cellulase; response surface
methodology; biological engineering

玉米秸秆是自然界中廉价、丰富的可再生纤维 提高土壤有机质含量，改善土壤结构 [2-3] ，具有反应
[4]
[1]
素类资源 。将微生物用于降解纤维素类物质可以 条件温和、投资少、成本低、无污染等特点 ，被

收稿日期：2020-04-05; 定用日期：2020-04-22; DOI: 10.13550/j.jxhg.20200291
基金项目：国家自然科学基金资助项目（131370649）；黑龙江省博士后资助经费（LBH-Z15200）
作者简介：刘晓飞（1980—），女，副教授，E-mail：liuxiaofei72@163.com。