大豆秸秆木聚糖碱法提取及酶解工艺研究

Alkaline extraction of xylan from soybean straw and its enzymolysis technology

大豆秸秆是木聚糖含量较高的一种农业纤维废弃物,采用碱法考察了不同前处理条件(包括预煮温度,氢氧化钠浓度,料液比和浸提时间等)对大豆秸秆中不溶性木聚糖的提取率的影响。正交实验结果表明:当预煮温度80℃,碱液浓度15%,料液比1∶20,浸提时间4 h时,大豆秸杆中不溶性木聚糖的提取率最高,为34.3%。低聚木糖是一种重要的功能性低聚糖,嗜热踝节菌木聚糖酶为低聚木糖水解用酶,通过单因素实验探究了在嗜热踝节菌木聚糖酶的催化作用下,大豆秸秆木聚糖水解的最佳条件,大豆秸秆在此方面研究尚属空白。实验结果显示:底物浓度为1.0%,酶添加量为30 U/m L,温度设定为60℃,水解时间为240 min的条件下低聚木糖的得率最高,为24.2%,在工业上具有较高的应用价值。

Soybean straw is a waste agricultural fiber,which contains a high xylan. The study investigated the effect of pretreatment parameters on the extraction rate of water insoluble xylan from soybean straw. The result shows that the best extraction conditions were ：Na OH solution 15%,solid-liquid ratio 1：20,extraction temperature 80 ℃ and extraction time 4h. Under the above conditions,the yield of xylan was up to 34.3%. xylooligosaccharides is an important functional oligosaccharides. Xylanase is a hydrolase catalyzing xylooligosaccharide. Using xylanase,high yield of reducing sugar was obtained when the conditions were as follows ：substrate concentration 1.0%,enzyme amount 30 U/m L,hydrolysis temperature 60 ℃ and hydrolysis time 240 min.