复合益生菌和纤维素酶发酵对艾草营养品质和微观结构的影响

Effects of Compound Probiotics and Cellulase Fermentation on Nutritional Quality and Microstructure of Artemisia argyi

本试验旨在研究复合益生菌和纤维素酶发酵对艾草化学成分、活性成分、发酵品质以及微观结构的影响,并研究其适宜发酵时间。以全株艾草粉(70%)和混合饲料(30%,由80%的玉米、10%的麸皮和10%的葡萄糖组成)为发酵底物,按照不同处理方式分为4个组,其中对照组不添加其他物质,复合益生菌组添加1%复合益生菌(含干酪乳杆菌1.0×10^6 CFU/mL、产朊假丝酵母菌1.0×10^8 CFU/mL和枯草芽孢杆菌1.0×10^6 CFU/mL),纤维素酶组添加1%纤维素酶(滤纸酶活力为130 FPU/g),菌酶联合组同时添加1%复合益生菌和1%纤维素酶,每个组设3个重复。将发酵底物混合均匀后,按照固体∶蒸馏水=5∶3(质量比)的比例添加蒸馏水,高压灭菌后进行发酵,发酵时长为7 d。结果表明:1)与对照组相比,单独添加复合益生菌除显著降低了艾草中半纤维素的含量(P<0.05)外,对其他各项纤维成分的含量无显著影响(P>0.05);单独添加复合益生菌、纤维素酶以及二者联合添加显著降低了艾草中中性洗涤纤维和半纤维素的含量(P<0.05);单独添加纤维素酶以及与复合益生菌联合添加均显著提高了艾草中粗蛋白质的含量(P<0.05),且菌酶联合组粗蛋白质含量显著高于其他各组(P<0.05)。2)与对照组相比,纤维素酶组与菌酶联合组艾草的pH显著降低(P<0.05),可溶性碳水化合物含量显著升高(P<0.05);菌酶联合组艾草中总黄酮和多酚含量显著升高(P<0.05)。3)纤维素酶组和菌酶联合组艾草表面微观结构显示凹凸不平,出现了大面积的破碎。4)菌酶联合组发酵第4天时,艾草中枯草芽孢杆菌、干酪乳杆菌和产朊假丝酵母菌的活菌数以及总黄酮和多酚含量均处在较高水平,其中产朊假丝酵母活菌数和总黄酮含量显著高于其他发酵时间(P<0.05)。由此得出,复合益生菌与纤维素酶联合添加显著降低艾草的pH,显著提高了可溶性碳水化合物、总黄酮和多酚的含量,改善了艾草的微观结构。复合益生菌和纤维素酶联合添加时艾草的适宜发酵时间为4 d。

This experiment was conducted to study the effects of compound probiotics and cellulase fermentation on chemical ingredients,active ingredients,fermentation quality and microstructure of Artemisia argyi,and to explore the optimum fermentation time.The whole-plant Artemisia argyi powder(70%)and compound feed(30%,composed of 80%corn meal,10%wheat bran and 10%glucose)were used as fermentation substrate in this experiment,and it was divided into 4 groups according to different treatment modes:control group did not add other substrates;compound probiotics group added with 1%compound probiotic(contained Lactobacillus casei 1.0×10^6 CFU/mL,Candida utilis 1.0×10^8 CFU/mL and Bacillus subtilis 1.0×10^6 CFU/mL);cellulase group added with 1%cellulase(filter paper activity was 130 FPU/g),and probiotics and enzyme combined group added with 1%compound probiotics and 1%cellulase,each group had 3 replicates.After blending the fermentation substrate,the distilled water was added according to solid:distilled water=5:3(mass ratio),and then fermented after high-pressure sterilization.The fermentation time was 7 d.The results showed as follows:1)compared with the control group,single addition of compound probiotics significantly decreased the hemi-cellulose content(P<0.05),but had no significant effects on other fibre composition contents of Artemisia argyi(P>0.05);single addition of compound probiotics and cellulase or combined addition of compound probiotics and cellulase significantly decreased the neutral detergent fiber and hemicellulose contents of Artemisia argyi(P<0.05);single addition of cellulase or combined addition of compound probiotics and cellulase significantly increased the crude protein content of Artemisia argyi(P<0.05),and the crude protein content of Artemisia argyi in the probiotics and enzyme combined group was significantly higher than that in other groups(P<0.05).2)Compared with the control group,the pH of Artemisia argyi was significantly reduced(P<0.05),while the water soluble carbohydrate content was significantly increased in the probiotics and enzyme combined group(P<0.05);the total flavonoids and polyphenols contents were significantly increased in the probiotics and enzyme combined group(P<0.05).3)The surface microstructure of Artemisia argyi in the probiotics and enzyme combined group showed to be uneven and more fragmented.4)On the 4th day of fermentation of the probiotics and enzyme combined group,the viable bacteria counts of Bacillus subtilis,Lactobacillus casei and Candida utilis and the contents of total flavonoids and polyphenols were in a high level,and the Candida utilis viable bacteria counts and total flavonoids content were significantly higher than other fermentation time(P<0.05).In conclusion,combined addition of compound probiotics and cellulase can significantly decrease the pH,significantly increase the contents of water soluble carbohydrate,total flavonoids and polyphenols,and improve the microstructure of Artemisia argyi,and the optimum fermentation time is 4 d.