纤维分解酶对大麦秸秆体外发酵和消化的影响

Effect of fibrinolytic enzyme on microbial adhesion and digestion of barley straw in vitro

本研究旨在评估外源纤维分解酶对大麦秸秆体外发酵和消化的影响。在试验1中外源纤维素酶主要由木聚糖酶和β-葡聚糖酶构成,酶浓度分别为0、30和300μg/mL,同时结合产琥铂酸丝状杆菌和黄色瘤胃球菌对苜蓿草和大麦秸秆进行体外消化。结果 :随着酶浓度的升高,中性洗涤纤维的降解率表现为显著线性升高(P <0.05)。产琥铂酸丝状杆菌和酶浓度在300μg/mL时对中性洗涤纤维的降解率具有显著的协同效应(P <0.05)。300μg/mL酶浓度时,黄色瘤胃球菌对苜蓿草的消化最高(P <0.05)。试验2评估了外源性纤维分解酶对大麦秸秆体外发酵的影响,在孵育前对外源纤维分解酶进行不同的预处理。结果 :纤维素酶预先水解后显著提高了大麦秸秆4和12h气体产生及4、12和48h干物质降解(P <0.05),无论大麦秸秆类型是什么,纤维素酶预处理后加入还原糖在各孵育时间干物质降解均显著低于对照组(P <0.05)。结论 :外源纤维分解酶可改善瘤胃细菌对纤维的消化能力,在瘤胃孵育前将纤维素酶进行预水解可以通过增加还原性糖的有效性来促进微生物生长。

The purpose of this study was to evaluate the effect of exogenous fibrinolytic enzyme on in vitro fermentation and digestion of barley straw.In experiment 1,the exogenous fibrinolytic enzyme was mainly composed of xylanase andβ-glucanase,with the enzyme concentration of 0,30 and 300 g/mL,respectively.At the same time,in vitro digestion of alfalfa and barley straw was carried out by combining with platinophilus oblate and yellow rumen coccus.Results:With the increase of enzyme concentration,the degradation rate of neutral detergent fiber showed a significant linear increase(P<0.05).There was a significant synergistic effect on the degradation rate of neutral scrubber at 300 g/mL(P<0.05).At 300 g/mL enzyme concentration,the digestibility of yellow rumen coccus to alfalfa was the highest(P<0.05).Experiment 2.When the effect of exogenous fibrinolytic enzyme on in vitro fermentation of barley straw was evaluated,different pretreatment of exogenous fiber decomposition enzyme was conducted before incubation.Results:the prehydrolysis of fibrinolytic enzyme significantly increased the gas production and dry matter degradation of barley straw at 4 and 12 h and 4,12 and 48 h(P<0.05).No matter what the type of barley straw was,the dry matter degradation of barley straw pretreated by fibrinolytic enzyme after adding reducing sugar at each incubation time was significantly lower than that of the control group(P<0.05).Conclusion:exogenous fibrinolytic enzyme can improve the digestibility of rumen bacteria to fiber.Prehydrolysis of fibrinolytic enzyme before incubation in the rumen can promote the growth of microorganisms by increasing the availability of reducing sugar.