作　　者： ; ; ; ; ; ; ;

机构地区： 徐州工程学院食品生物工程学院

出　　处： 《食品科学》 2013年第13期186-192,共7页

摘　　要： 以保藏的黑曲霉菌种作为菌源,利用黑曲霉细胞深层发酵法生产内切型菊粉酶。以牛蒡为唯一碳源,获得产菊粉酶菌株;通过测定发酵液酶活,从20株黑曲霉菌株筛选得到产菊粉酶活力最高的编号为08013的一株黑曲霉菌株,酶活力为3.27U/mL。通过单因素试验对最佳发酵时间和不同的营养条件对黑曲霉产菊粉酶的影响进行研究。结果表明:最佳发酵时间为108h,最佳金属离子为Na+,质量浓度为0.5g/100mL;最佳碳源为牛蒡汁,体积分数为10%;最佳有机氮源为酵母膏,质量浓度为2g/100mL;最佳无机氮源为(NH4)2HPO4,质量浓度为2g/100mL。在单因素试验的基础上,采用Box-Behnken响应面试验设计对内切型菊粉酶生产菌株发酵培养基配方中的牛蒡汁体积分数、酵母膏和(NH4)2HPO4的质量浓度进行定量研究,建立并分析各因素与酶活关系的数学模型。得到培养基最优配方为牛蒡汁9.98%、酵母膏1.74g/100mL、(NH4)2HPO41.82g/100mL时,此时菊粉酶酶活力最高,为7.23U/mL。经验证,在此条件下进行实验,测得菊粉酶酶活力为7.26U/mL,与理论计算值7.23U/mL基本一致。说明回归模型能较好地预测菊粉酶酶活。通过对发酵培养基的优化,使最终酶活比初始酶活力(3.27U/mL)提高了122%。 The production of endoinulinase by Aspergillus niger in submerged cultivation was studied.Burdock was used as the only carbon source.Among 20 Aspergillus niger strains tested,strain 08013 exhibited the highest endoinulinase activity of 3.27 U/mL in the fermentation supernatant.Preliminary results from this study showed that the optimal fermentation time,metal ion,carbon source,organic nitrogen source and inorganic nitrogen source were 108 h,0.5 g/100 mL of sodium ion,burdock,2 g/100 mL of yeast extract,2 g/100 mL of（NH4）2HPO4,respectively.Response surface BoxBehnken design was used to optimize burdock,yeast extract and（NH4）2HPO4 concentration.A mathematical model was developed and analyzed indicating the effect of the studied variables on endoinulinase activity.The optimal culture medium for producing endoinulinase contained 9.98% of burdock juice,1.74 g/100 mL of yeast extract and 1.82 g/100 mL of（NH4）2HPO4.The maximum predicted endoinulinase activity under the optimized conditions was 7.23 U/mL,which was close to the experimental value of 7.26 U/mL.Thus the regression model developed in this study had good prediction ability.This experimental value exhibited an increase of 122% compared with that obtained before optimization.

关 键 词： 菊粉酶 黑曲霉 发酵培养基 优化 响应面法

领　　域： [轻工技术与工程] [轻工技术与工程]