葡萄糖添加水平及接种量对牛链球菌增殖及乳酸发酵的影响  

Effects of different glucose concentration and inoculation dose on the proliferation and lactic acid fermentation of Streptococcus bovis

作　　者：张琪[1] 瞿明仁[1] 欧阳克蕙[1] 鲁友友[1] 熊小文[1] 潘珂[1] 吴登堃[1] 

机构地区：[1]江西农业大学动物科学技术学院

出　　处：《中国饲料》2013年第24期12-16,共5页China Feed

基　　金：现代农业产业技术体系项目(nycytx-38);国家自然科学基金(31260561);江西省教育厅项目(GJJ13274)

摘　　要：牛链球菌是反刍动物瘤胃内重要的产乳酸菌。本试验通过体外培养，探讨葡萄糖添加水平以及接种量对牛链球菌增殖及乳酸发酵的影响。分别以葡萄糖添加水平（2．5、5．0、10．0、20．0mg／mL）和接种量（5、10、20、40μL／mL种子液）为试验因子，体外培养0、2、4、6、12、24h，测定牛链球菌增殖及乳酸发酵动态。结果表明：高糖有抑制培养前期（2～6h）牛链球菌增殖的作用（P〈0．05），但随着牛链球菌菌群密度的增加，高糖的抑制作用逐渐减弱；高糖对乳酸产量无显著影响（P〉0．05），但超过10．0mg／mL的高糖极显著增加了牛链球菌的耗糖量（P〈0．01），极显著降低了产乳酸效率（P〈0．01）。接种量提高到20μL／mL后显著促进了牛链球菌的增殖（P〈0．05），增加了生长高峰期（4～6h）乳酸产量（P〈0．05）和耗糖量，且20μL／111L接种量组乳酸产量最高；但对产乳酸效率无显著影响（P〉0．05）。由此可见，体外条件下，高葡萄糖水平有抑制牛链球菌增殖、改变乳酸发酵途径、降低牛链球菌产乳酸效率的作用；而高接种量促进了牛链球菌的生长．增加了乳酸产量．但对牛链球菌的乳酸发酵途径无影响。Streptococcus bovis was one of the important bacteria which could produce lactic acid in the rumen.In this experiment,S, bovis were cultivated in vitro under different glucose concentration and inoculation dose to determine the effects on proliferation and lactic acid fermentation.Different concentration of glucose （2.5,5.0,10.0,20.0 mg/mL）and dif- ferent dose of inoculation （5,10,20,40 μ/mL seed liquid） were added into the nutrient solution for S. bovis in vitro cul- ture.The proliferation of S. bovis and results of lactic acid fermentation were measured after culturing 0,2,4,6,12,24 h. The results showed that： high glucose concentration inhibited S. bovis proliferation in the early culture period（2 - 6 h）（P 〈 0.05）,but with the density of S. bov/s increasing,the inhibition by high glucose concentration decreased ;there was no effect on lactic acid production （P 〉 0.05）,but the glucose consumption of S.bovis was significantly increased while glu- cose concentration was higher than 10.0 mg/mL （P 〈 0.01 ）.However,high glucose concentration reduced efficiency of lac- tic acid production significantly （P 〈 0.05）.When the inoculation dose was increased to 20μL/mL in the culture solution, the amount of S. bovis was promoted significantly and the production of lactic acid and the consumption of glucose in the summit growth period （4 - 6 h）was also enhanced （P 〈 0.05）.The yield of lactic acid of 20 μL/mL group was the highest. However,it didn＇t make a significant effect on the efficiency of lactic acid production （P 〉 0.05）.In this experiment, high concentration of glucose could inhibit the proliferation of S. bovis, change the lactic acid fermentation pathway,reduce the efficiency of lactic acid production.While,high dose of inoculation promoted the growth of S. bov/s ,increased the produc- tion of lactic acid, but had no effect on lactic fermentation pathway.

关 键 词：牛链球菌 体外发酵 乳酸 发酵途径 

分 类 号：S816.3[农业科学—饲料科学]