摘要
为提高纤维素酶产量,以匍枝根霉TP-02为出发菌株,通过诱变选育纤维素酶高产突变株,并研究碳源、氮源以及氨基酸等物质对菌株产酶能力的影响.经紫外和甲基磺酸乙酯复合诱变后筛选得到一株高产菌株TZ-03,其滤纸酶活(FPA)为4.96IU/mL,较TP-02提高了37.8%.优化后最佳发酵培养基为:微晶纤维素20g/L,鱼粉蛋白胨10g/L,麸皮浸出汁2.5%,CaCl_22g/L,MgSO_4·7H_2O 4g/L,KH_2PO_43g/L,谷氨酰胺1g/L,PEG-4000 0.25g/L,Tween 80 200μL/L,微量元素液1mL/L.此条件下TZ-03的FPA酶活高达11.58IU/mL.通过对发酵过程中溶氧、pH和补料条件的控制,进行10L发酵罐放大实验,最终使该突变株的FPA酶活在84h达到峰值21.32IU/mL,与摇瓶发酵相比提高了89.8%.β-葡萄糖苷酶(BG)、内切酶(EG)和外切酶(CBH)的酶活峰值分别为41.0IU/mL、26.76IU/mL和16.94IU/mL.通过诱变及发酵优化成功提高了纤维素酶产量,为纤维素酶的工业化应用奠定了一定的基础.
To improve the yield of cellulase, the parent strain Rhizopus stolonifer TP〈02 was mutagenized to obtain a high yielding mutant.The effect of carbon sources,nitrogen sources and amino acid addition on the cellulase production was studied.Through the UV mutagenesis combined with ethyl methanesul fonate （EMS） mutagenesis,a high yielding strain TZ O3 was obtained.The filter paper activity （FPA） of the mutant was 4. 96 IU/mL （37.8% higher than that of TP O2）.The optimal media were confirmed as follows：Avicel 20 g/L,peptone 10 g/L,wheat bran extract 2.5%,CaCl2 2 g/L,MgSO4 · 7H2O4 g/L, KH2PO4 3 g/L, glutamine 1 g/L, Tween 80 200 〉L/L, PEG 4000 0.25 g/L, trace element solution 1 mL/L.In the above condition ,the FPA of TZ 03 peaked at 11.58 IU/mL.The amplification experiment was carried out in 10 L fermentor with the control of dissolved oxygen,pH and feeding conditions in the fermentation process.The results showed that the maximum of FPA was 21.32 IU/mL peaked at 84 h （89.8% higher than that in the shake flask culture conditions）.The highest β-glycosidase （BG） activity, endoglucanase （EG） activity and cellobiohydrolase （CBH） activity were 41.06 IU/mL,26.76 IU/mL and 16.94 IU/mL,respectively.In this study, the yield of cellulase from Rhizopus Stolonifer TZ -03 was effec tively increased by the breeding of high yielding mutant and optimization of fermentation conditions,lay ing a foundation for the industrial production and application of cellulase.
作者
郑贤金
汤斌
ZHENG Xianjin;TANG Bin(College of Biological and Chemical Engineering,Anhui Polytechnic University,Wuhu 241000,China)
出处
《安徽工程大学学报》
CAS
2018年第4期13-18,共6页
Journal of Anhui Polytechnic University
基金
国家自然科学基金资助项目(31270135)
关键词
匍枝根霉
纤维素酶
诱变选育
发酵优化
Rhizopus stolonifer
celllulase
mutation breeding
fermentation optimization
