天然产物研究与开发 ›› 2023, Vol. 35 ›› Issue (2): 221-230.doi: 10.16333/j.1001-6880.2023.2.005

• 研究论文 • 上一篇    下一篇

高产纤维素酶芽孢杆菌的筛选、鉴定与发酵条件优化

杨艳红1*,张浩铂2,姚心怡2,贺   禧2,王   哲2   

  1. 1重庆理工大学药学与生物工程学院,重庆 400054;2重庆市育才中学,重庆 400050
  • 出版日期:2023-02-28 发布日期:2023-03-02
  • 基金资助:
    重庆市雏鹰计划(CY210906)

Screening,identification and fermentation condition optimization of Bacillus with high cellulase production

YANG Yan-hong1*,ZHANG Hao-bo2,YAO Xin-yi2,HE Xi2,WANG Zhe2   

  1. 1School of Pharmacy & Bioengineering,Chongqing University of Technology,Chongqing 400054,China;2Chongqing Yucai Secondary School,Chongqing 400050,China
  • Online:2023-02-28 Published:2023-03-02

摘要:

纤维素是生产生物质能源最广泛、最廉价的原材料,筛选高活性纤维素酶菌株是纤维素能源开发利用的关键。采用刚果红-CMC平板筛选高产纤维素酶菌株;结合菌株形态、生理生化特征及16S rDNA序列分析对菌株进行鉴定;采用正交实验筛选菌株AF1的最佳产酶发酵条件。筛选获得 5 株高活力的纤维素酶产生芽孢杆菌,鉴定为2株枯草芽孢杆菌(Bacillus subtilis)、3株解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。5株菌的水解圈直径与菌落直径比值均大于4.5,其中解淀粉芽孢杆菌AF1最大达到8.04,优化AF1菌株最佳固体发酵培养基为:玉米秸秆粉20 g,NaCl 0.4 g,CaCl2 0.2 g,麸皮32 g,吐温80 0.2 g ,蛋白胨0.7 g,(NH4)2SO4 0.8 g ,KH2PO4 0.5 g,MgSO4·7H2O 0.04 g,糖蜜0.4 g,吐温20 0.4 g,水115 mL;最佳理化发酵条件为:温度30 °C、pH 6.5、接种量1.5%(OD600=1.0)。在最佳条件下发酵42 h,最高酶活达26.904 U/g,为纤维素酶制剂研究和生物能源的开发提供菌株来源。

关键词: 纤维素酶, 16S rDNA, 菌株鉴定, 芽孢杆菌, 发酵条件

Abstract:

Cellulose is the most widespread and cheapest raw material for biomass energy production.Screening of high-activity-cellulase-producing strain is the key to the development and utilization of cellulose energy.Congo red-CMC plate was used to screen cellulase-producing strains.The strains were identified by morphological,physiological,biochemical characteristics and 16S rDNA sequence analysis.The optimal fermentation conditions of strain AF1 were screened by orthogonal experiments.Five cellulase-producing strains with high activity were obtained and identified as two strains of Bacillus subtilis and three strains of Bacillus amyloliquefaciens.The ratio of the hydrolytic circle diameter and colony diameter of the five strains was more than 4.5,and AF1 was the maximum reaching to 8.04.The optimal solid fermentation medium for AF1 strain was:corn straw powder 20 g,NaCl 0.4 g,CaCl2 0.2 g,bran 32 g,twain 80 0.2 g,peptone 0.7 g,(NH4)2SO4 0.8 g,KH2PO4 0.5g,MgSO4·7H2O 0.04 g,molasses 0.4 g,twain 20 0.4 g,water 115 mL;The optimal physical and chemical fermentation conditions were as follows:temperature 30°C,pH 6.5,inoculum amount 1.5%(OD600=1.0).And under these optimal conditions,the maximum α-amylase activity is obtained 26.904 U/g after 42 h,which could provide strain source for cellulase preparation research and bio-energy development.

Key words: cellulase, 16S rDNA, strain identification, Bacillus, fermentation conditions

中图分类号:  R914