[关键词]
[摘要]
本研究以小麦麦麸为原料,分别采用3株泡盛曲霉(分别为GIM3.266,GIM3.4,GIM3.5)进行连续8天的固态发酵,每天分别提取发酵过程中小麦麦麸中不同存在形态酚类物质并测定其含量,同时,每天测定3株泡盛曲霉在发酵过程中木聚糖酶、纤维素酶以及阿魏酸酯酶的活性变化。结果表明,与未经发酵的麦麸相比,经泡盛曲霉发酵后的麦麸游离型酚类物质的含量显著增加,总酚含量可高达11561.30 μg/g麸皮,比发酵前的麸皮总酚提高了169%;另外,酶活力的结果表明:纤维素酶活力在发酵前三天显著增大,其活力最高可达156.70 U,木聚糖酶活力随总酚释放量的增加而增加,最高可达34123.00 U,阿魏酸酯酶活力在发酵中后期达到顶峰,最高可达2642.60 U。总体而言,麦麸发酵过程中酚类物质的释放量与木聚糖酶和阿魏酸酯酶的酶活力呈正相关,说明发酵后麦麸中酚类物质提取量的显著增加与这两种酶密切相关,这两种酶活力高的泡盛曲霉菌株,更有利于释放麦麸中的酚类物质。
[Key word]
[Abstract]
In the present study, solid state fermentation of wheat bran was performed by three Aspergillus awamori strains (GIM3.266, GIM3.4, GIM3.5, respectively) at 28℃ for 8 days consecutively. Different forms of phenols in wheat bran were extracted and analyzed using the Folin-Ciocaltey method on a daily basis. The activities of xylanase, cellulase, and feruloyl esterase were also investigated during the fermentation process. It was showed that the contents of free phenolic compounds increased sharply after fermentation. The total phenolic content could reach 11561.30 μg/g wheat bran, increasing by 169% than the unfermented wheat bran. Besides, it was found that the activity of cellulose and xylanase increased during the early stage of fermentation, peaking at 156.70 U and 34123.00 U respectively. The activity of feruloyl esterase could reach a peak of 2642.60 U in the middle and later periods. In general, positive correlations were found between the contents of phenolic compounds and the activities of xylanase and feruloyl esterase, revealing that synergistic effects of these two enzymes during fermentation can lead to higher contents of phenolic compounds.
[中图分类号]
[基金项目]
中央高校基本科研业务费专项资助项目(2013ZM0065);广东省天然产物绿色加工与产品安全重点实验室开放基金资助项目(201304)广东省高等学校科技创新重点项目(2012CXZD0009);国家自然科学基金项目(31201330);广州市科技攻关项目(201300000202)