仔猪源罗伊氏乳酸杆菌生物学特性的研究

Study of Biological Characteristics of Lactobacillus reuteri Originated from Piglet

研究了罗伊氏乳酸杆菌的生物学特性包括生长曲线、耐热存活率、耐酸存活率、贮藏存活率以及发酵参数。采用均匀设计的试验设计对影响乳酸杆菌发酵较大的6个因素如碳源、氮源和时间进行优化。试验结果表明,罗伊氏乳酸杆菌的浓度在开始时有所下降,经过2h之后从1 0×103数量级迅速上升,到第22h接近1 0×1010数量级,到40h细菌的数量级开始缓慢下降。75℃处理15min之后存活率为31 3%,经过1个月贮藏存活率为85 5%,pH2 0处理6h的存活率为72%.优化的发酵参数为:时间20h;葡萄糖10g/L;蔗糖60g/L;胰蛋白胨30g/L;酵母浸粉5g/L;柠檬酸铵12g/L.试验表明了罗伊氏乳酸杆菌具有良好的抗逆性,生长繁殖迅速,可以用作益生菌生产菌种。

The biological characteristics of the L.reuteri originated from weaning piglet were investigated and fermentation parameters was optimized by means of uniform design. Lactobacillus growth curve, survivability after 75℃ treatment for 15 min, pH 2.0 treatment for 6 h and storage for 1 month, respectively, were measured. The concentration of L. reuteri decreased slightly in the first hour and increased very quickly from 1.0×10~3 CFU/mL to about 1.0×10^(10) CFU/mL in 22h, but fell down in 40h. L.reuteri survivability after 75℃, storage, and pH 2.0 treatment was 31.3%,85.5%,72%, respectively and optimized fermentation parameters were as follows: culture time 20h, glucose 10g/L, sucrose 60g/L, peptone 30g/L, yeast extract 5g/L, and ammonium citrate 12g/L. The lactobacillus showed excellent growth characteristics and good resistance to stress so it can be used in piglet feed as a probiotics bacterium.