响应面法优化黄芪固体发酵工艺

Optimization of the Solid Fermentation Conditions of the Astragalus by Response Surface Methodology

以黑曲霉为发酵菌种,黄芪粗多糖含量为响应值,确定黄芪固体发酵的最佳工艺。在单因素试验的基础上,以发酵温度、发酵时间、接种量为响应因素,以黄芪粗多糖含量为响应值,利用Box-Behnken中心组合方法进行三因素三水平试验设计,进行响应面分析。结果表明:影响黄芪粗多糖含量的因素主次顺序为发酵温度、发酵时间和接种量,最佳发酵工艺条件为:发酵时间7.3 d,发酵温度28.5℃,接种量5%,在此条件下进行验证试验,粗多糖平均含量为84.74 mg/g,低于预测值1.57%。该工艺对黄芪粗多糖固体发酵优化效果显著,为黄芪的进一步开发利用提供了试验依据。

To determine the optimal conditions of solid fermentation of the Astragalus polysaccharides by Aspergillus niger. On the basis of single factor experiments,a three-factors three-levels Box-Behnken central composite design was utilized. On the mathematical modeling for polysaccharides content as response to fermentation time,fermentation temperature and inoculum concentration,followed by responses surface analysis of the relationship between the variables. The results showed that the factors influencing the content of Astragalus polysaccharides were fermentation temperature,fermentation time and inoculum concentration. The optimal fermenting conditions were as follows: fermentation time was 7.3 d,fermentation temperature was 28.5 ℃,inoculum concentration was 5 %. Under such conditions,the actual average content after experiment was 84.74 mg/g,lower than estimated content 1.57 %. The optimization of solid fermentation of Astragalus polysaccharides was obvious,which provide the certain experimental basis for deep research of Astragalus.