| 摘要: |
| 利用刚果红鉴别培养基及基础液体筛选培养基进行菌种筛选,从新疆盐碱地分离得到的16株菌株中筛选获得一株产纤维素酶活力较高的菌株S-16,对该菌株进行16SrDNA鉴定,确定该菌为枯草芽胞杆菌(Bacillus subtilis)。对S-16发酵产纤维素酶的主要影响因素进行研究,分别考察了碳源、氮源、培养基初始pH和接种量等因素对发酵产纤维素酶的影响。结合单因素影响实验得到优化后的培养基配方为:羧甲基纤维素钠1.5%,酵母粉1%,NaCl 1%,MgSO_4·7H_2O 2‰,KH_2PO_4·3H_2_O 1‰。优化后的发酵条件为:初始pH为8,接种量1%,种龄8h,培养时间48h。经过发酵工艺优化,S-16产生的羧甲基纤维素酶活(CMCase)和滤纸酶活(FPase)分别达到4.64IU/mL和0.46IU/mL,与初始培养条件下的酶活相比分别提高了3.14倍和1.30倍。本研究得到的枯草芽胞杆菌S-16及其优化发酵工艺为秸秆的快速腐熟和高产纤维素酶的应用奠定了基础。 |
| 关键词: 纤维素酶 枯草芽胞杆菌 菌种筛选 发酵优化 |
| DOI： |
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| Screening of high yield cellulase Bacillus subtilis S-16 and optimization of its fermentation process |
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SHI Lu,LI Yang,LI Guolong,MA Xin,GU Jingang,LI Shunyi,College of Life Sciences,Hubei University
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College of Life Sciences,Hubei University,Agricultural Culture Collection of China
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| Abstract: |
| In this study,a high-yield cellulase producing strain S-16 was screened from saline-alkali soil in Xinjiang and identified as Bacillus subtilis by its 16 SrDNA sequence.The effects of carbon source,nitrogen source,inorganic salt,pH and inoculation size on the cellulase production were investigated.Our results showed that,the optimum fermentation medium was:carboxymethylcellulose(CMC-Na)1.5%,yeast extract 1%,NaCl 1%,MgSO4·7H_2O_2‰and KH_2PO_4·3H_2O 1‰;the optimum cultivation conditions were initial pH 8,inoculum amount 1.0%(v/v),and inoculum age 8h.Under the optimum fermentation condition,the maximum CMCase and filter paper activity reached4.64IU/mL and 0.46IU/mL,increased by 3.14-fold and 1.30-fold compared with the activities under initial circumstance,respectively.This study provided a promising strain and an optimized fermentation conditions for the high-level production of cellulase. |
| Key words: cellulase Bacillus subtilis strain screening fermentation optimization |
