液体发酵制备木聚糖酶及其对育肥猪生长性能与血液生化指标的影响

采用黑曲霉菌3.3162液体发酵制备木聚糖酶,研究发酵条件对酶活力的影响,按优化条件扩大发酵制备木聚糖酶干粉,研究其添加到小麦日粮中对育肥猪生产性能和血液生化指标的影响。选择杜长大三元猪60头,随机分成3个处理组,分别饲喂玉米型日粮和两种小麦加酶日粮(将日粮中玉米的60%直接用小麦代替,酶制剂添加量均为0.18g·kg-1,一组为试验中自制木聚糖酶,另一组为市售复合酶木聚糖酶54000U·g-1,葡聚糖酶42000U·g-1)进行饲养试验。结果表明,利用黑曲霉菌进行液体发酵是理想的木聚糖酶生产工艺,最适发酵条件为pH6、麦麸比例2%、吐温80添加量0.1%与摇瓶装液量50mL。动物试验证明,小麦代替玉米并添加酶制剂饲喂猪可以获得理想的生产性能,但会引起一些血液生化指标的变化。

Production of xylanase by submerged fermentation and effect of its preparation on growing pigs based on wheat-based diet

To study the production of xylanase by submerged fermentation and effect of its preparation on growing pigs based on wheat-based diet. Xylanase preparation was carried out by submerged fermentation with Aspergillus niger 3.3162, the effects of fermentation condition on xylanase synthesis were studied. Sixty pigs were divided into 3 groups. 60% corn was replaced by wheat based on control diet, one was supplemented with xylanase (from front experiment), the other one was supplemented with compound enzyme (xylanase 54 000 U·g-1, β-glucanase 42 000 U·g-1). The result showed that submerged fermentation was a good way to product xylanase and the optimum conditions of producing xylanase were:pH 6, wheat bran proportion 2%, Tween 80 0.1%, culture medium cubage 50 mL. 60% corn was replaced by wheat based on control diet supplemented with enzyme in-crease weight gain, activities of creatine kinase and alkaline phosphatase in serum, decreased glucose and tri-acylglycerol, but had no effect on inosine, activitie of lactate dehydrogenase and total cholesterol. Animal experiment indicate that to feed pigs with wheat and xylanase instead of corn can gain ideal growth performance, but can bring some changes in the biochemical indexes of blood.