摘要
为分离出耐低温纤维素酶高产真菌菌株,并进行菌株的产酶条件优化,获得最大的酶活力。通过刚果红染色法初筛以及3,5-二硝基水杨酸(DNS)酶活测定法复筛,分别从长白山地区的牛粪和土壤中各分离出1株耐低温高效纤维素降解真菌,并对其进行形态学鉴定、分子生物学鉴定以及产酶条件研究。结果显示经初筛和复筛得到2株耐低温纤维素降解菌FF2-2和F-3I,其FPA酶活分别为(11.23±0.39)和(5.59±0.36)U/m L。通过形态学和ITS rRNA分子生物学鉴定,菌株FF2-2被鉴定为短梗霉属的出芽短梗霉Aureobasidium pullulans,菌株F-3I为曲霉属的花斑曲霉Aspergillus versicolor;菌株FF2-2和F-3I产酶的最适碳源分别是w=0.5%的麸皮、w=0.5%的淀粉;最适氮源分别为w=1%牛肉膏和硫酸铵混合物、w=1%牛肉膏;最适初始p H分别为7.0和6.0;最适发酵温度均是23℃;最适发酵时间分别是3 d和5 d。优化后菌株FF2-2和F-3I的FPA酶活力分别提高了2.6倍和5.5倍。
In order to screen the efficient cold-adapted cellulase-decomposing strains and optimize conditions for maximum production of enzyme activity,in this study,we isolated the cold-adapted cellulose-decomposing strains with congo red method and flask fermentation from cattle manure and the soil of mountain. The strains were identified by morphological observation and molecular biology identification,and their fermentation condition were also optimized. The result showed that their FPA were（ 11. 23 ± 0. 39）U / m L,（ 5. 59 ± 0. 36） U / m L,and the strain FF2-2 and F-3I were respectively identified as Aureobasidium pullulans and Aspergillus versicolor. The optimum carbon and nitrogen source of two strains were 0. 5% wheat bran,0. 5 % starch,and 1 % beef extract and ammonium sulfate mixture,1 % beef extract,respectively. The optimum p H were 7. 0 and 6. 0,respectively. The optimum fermentation temperature for both strains was 23 ℃,and the optimum fermentation time was 3 d,5 d respectively. The FPAs of strain FF2-2 and F-3I increased 2. 6 and 5. 6 times respectively after optimization.
出处
《中山大学学报（自然科学版）》
CAS
CSCD
北大核心
2015年第5期115-121,129,共8页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
国家现代农业产业技术体系建设专项资助项目(CARS-38)
公益性行业(农业)科研专项资助项目(201303091)
关键词
长白山地区
低温纤维素分解菌
鉴定
产酶条件优化
Changbai Mountain＇s District
cold-adapted cellulase-decomposing strains
identification
optimization of enzyme production conditions
