摘要
从土壤中筛出一株生长快产木聚糖酶活力较高的黑曲霉(Aspergillus niger)C-2菌株,经紫外线和甲基磺酸乙酯诱变,获得一突变株 An-76,其生长减缓,孢子形成能力减弱,产生的木聚糖酶和β-木糖苷酶活力分别可达353.6IU/ml 和4.5IU/ml。测定了 An-76的正常产酶曲线,研究了麸皮、氮源、碳源及半纤维素浓度对产酶的影响。最适培养条件为:起始 pH6.0、28℃、96h。酶的最适作用条件为50-55℃,pH4.8,在 pH1.2—11.4范围内稳定。酶的热稳定性较差,55℃保温1小时,剩余活力为40%。只有在含木糖苷类物质存在时,An-76才大量合成木聚糖酶。
A rapid growing and high xylanase pro-ducing fungus Aspergillus niger C-2 wasisolated from the soil.After combinationtreatment with UV and EMS,a mutant An-76which grew slowly and produced small co-lonies was obtained,The β-xylanase and β-xylosidase activities of culture filtrate of An-76 were 353.6 IU/ml,and 4.5 IU/ml,respecti-vely.Course of the enzyme production andeffects of wheat bran,nitrogen and carbonsources,concentration of hemicellulose onenzyme productions were inverstigated.Theoptimal culture conditions are following:in-itial pH 6.0,temperature 28℃,and cuhiva-tion time 96h.The optimal pH and tempera-ture for xylanase reaction were pH 4.8 and5.0—55℃.Xylanase was stable in the pHrange 1.2—11.4,but had a weak thermal sta-bility.Having incubated the enzyme at 55℃for 1 h,40% of enzyme activity remaining.Significant amount of the enzyme was produc-ed only by xylosic materials.
出处
《微生物学报》
CAS
CSCD
北大核心
1990年第5期351-357,共7页
Acta Microbiologica Sinica
