Preparation Of Inulin And Study On Lactobacillus Microencapsulation

In order to study animal microecological preparation, a production extraction of Jerusalem artichoke, Inulin Fructan(GFn) ,was extracted through hot water extracting. And the study showed that the effect of inulin to Lactobacillus and the antimicrobial activity of Lactobacillus to E.coli, S.typhimurium, Sta.aureus.Then resistance to stress/bad conditions of Lactobacillus including thermoresistance,acid resistance,bile salt resistance and stability during storage was detected by plate count technique.And microencapsulation technique was adopted to immobilize Lactobacillus to improve its survival in detrimental conditions. Finally, The experiment studied the cooperation effect of inulin and microcapsules Lactobacillus on productive performance and immunity of weaned piglets.The results showed:(1) The inulin content was measured with the 90 percent of reducing sugar.Reducing sugar was determined by the dinitrosalicylic acid method using D(一)Fructose as standard.The mathematical model was expressed according to following equation:y=0.7564x-0.1107(R2=0.9998). The inulin content was 86.3%.(2) The experiment got the growth OD600nm and pH of Lactobacillus in sealed bottles with different levels of inulin. The results showed that the best percent of inulin was 1% to L.planticola and L.bulgaricus.But with the increase of inulin, the growth and reproduction of Lactobacillus had almost no change.(3) L.planticola was sensitive to rigrous conditions was studied. Incubated in simulated gastric juice(pH=1.5)for 0.5h, no flora could be detected.And incubated (pH=2.5)for 2.5h,the number of viable L.planticola was decreased about 2 log count. When the culture was heated from 40℃to 70℃and kept for 60s,the number of viable L.planticola decreased from 6.6×10⁹ to 0. Higher temperature,longer time,less culture would make less viable bacteria survive. When the culture was stored in liquid at ambient temperature for 15d,the number of viable L.planticola was decreased about 2 log count.The L.planticola had better tolerance in 3% bile salt and antimicrobial activity to E.coli, S.typhimurium and Sta.aureus.(4) The extrusion method was selected for microencapsulating L.planticola.Sodium alginate has good bio-compatibility and the gel is soluble in intestinal juice but not in gastric juice.It was used as the wall material of Lactobacillus microencapsulation in this study.We had found out the optimum process of making microcapsule and addtive magnitude of supporters though the orthogonal experiment .The results showed that the optimum conditions for microencapsulation were established as follows:the alginate concentration as 3%, skim milk as 4%, milk sugar as 6%, calcium chloride as 2%,and its livability reached 7.67×10¹⁰cfu/g. The resistance to stress/bad conditions of Lactobacillus microencapsulation including acid resistance and stability during storage had been greatly improved.(5) The cooperation effect of inulin and microcapsules Lactobacillus on productive performance and immunity of weaned piglets was studied.Compared with the control, the average daily gain(ADG) of L.lactis group and sybiotics group increased by19.63%(P<0.01),24.85%(P<0.01), CD4+/CD8+ increased by 3.70%(P<0.05),5.56%(P<0.05), mononuclear phagocyte increased by 12.21%(P<0.05),13.17%(P<0.05); The sybiotics group had better effect than the L.lactis group, but which was not remarkable.