南方农业学报2025，Vol.56Issue(3)：772-785,14.DOI:10.3969/j.issn.2095-1191.2025.03.009
1株几丁杆菌的酶学特性及其对虾壳废弃物的降解作用
Enzymatic characteristics of a Chitinibacter strain and its degradation effects on shrimp shell waste
摘要
Abstract
[Objective]To isolate and identify chitinase high-yielding strains from natural environment soil samples,carry out enzymatic characterization of chitinase,and evaluate the efficacy of the strain in chitin degradation,which could provide theoretical basis for the industrial transformation of chitin-rich shrimp shells and other waste resources,as well as the realization of chitin resources in the green application of environmental protection.[Method]The chitinase high-yielding strains were screened by the colloidal chitin plate hydrolysis circle method,and identified by physiological and biochemical characteristics analysis and molecular biological identification techniques.The enzyme activity characte-ristics and fermentation conditions were studied using the 3,5-dinitrosalicylic acid(DNS)method,and the degradation rates of colloidal chitin and shrimp shells were determined by weight loss method.[Result]A chitinase high-yield strain was successfully isolated from the soil samples.After identification,the strain belonged to genus Chitinibacter,and was named as Chitinibacter sp.strain CQNU6-1.The enzyme activity analysis showed that the optimal culture conditions for this strain were 30℃and pH 7.0,under which the chitinase activity reached 0.547 U/mL after 120 h.The chitinase pro-duced by this strain showed the highest relative enzyme activity at 40℃and pH 6.0,and it could still maintain more than 70.0%of the relative enzyme activity under the high temperature of 70℃and the strong alkaline environment of pH 10.0,showing good thermal stability and acid-base adaptability.At ion concentrations of 0.01 and 0.1 mol/L,Na+,K+,Mg2+,Ca2+,Fe3+and Mn2+could enhance the relative enzyme activity of chitinase,among which the enhancement effect of Mn2+was the most obvious,whereas the inhibitory effect of Cu2+on relative enzyme activity was observed.In addi-tion,CQNU6-1 strain was able to grow in the medium with chitin as the sole carbon source and showed significant degra-dation effects on colloidal chitin and chitin-rich shrimp shells,with degradation rates of up to 100.0%and 78.7%respec-tively.Meanwhile,the chitinase produced by this strain could be preliminarily enriched and purified by ammonium sulfate precipitation method.[Conclusion]The screened chitinase high-yielding strain Chitinibacter sp.strain CQNU6-1 exhibits wide adaptability to fermentation temperature and pH.It demonstrates good chitin biodegradation ability under high-temperature and alkaline conditions.关键词
几丁质酶/菌株鉴定/发酵条件优化/酶学性质/虾壳废弃物降解Key words
chitinase/strain identification/optimization of fermentation conditions/enzymatic properties/degrada-tion of shrimp shell waste分类
农业科技引用本文复制引用
管箫,李督福,海钱敏,刘厶铭,童金凤,马振刚..1株几丁杆菌的酶学特性及其对虾壳废弃物的降解作用[J].南方农业学报,2025,56(3):772-785,14.基金项目
国家自然科学基金项目(32372944) （32372944）
重庆市教育委员会科学技术研究计划项目(KJQN202100543) （KJQN202100543）
重庆市高等教育教学改革研究项目(223140) （223140）
重庆师范大学大学生创新训练计划项目(X202410637025) Natural Science Foundation of China(32372944) （X202410637025）
Science and Technology Research Plan Pro-ject of Chongqing Municipal Education Commission(KJQN202100543) （KJQN202100543）
Chongqing Higher Education Teaching Reform Research Project(223140) （223140）
Innovative Training Project for College Students of Chongqing Normal University(X20241 0637025) （X20241 0637025）
