微囊化屎肠球菌活菌制剂的研究

Study on the production technology and properties of microencapsulated Enterococcus faecium

【目的】研究制备新型微囊化屎肠球菌活菌制剂的方法。【方法】采用发酵前包被工艺,对屎肠球菌进行微囊化,在加入适量氯化钙的MRS培养基中进行固化培养,过滤收集微胶囊,45℃干燥后得到微囊化屎肠球菌活菌制剂。采用平板菌落计数法评价其对80℃高温、模拟胃肠液及常温贮藏条件的耐受能力。【结果】采用发酵前包被工艺获得的微囊化屎肠球菌液态产品的活菌数较发酵后包被工艺提高了2 lgCFU/mL。通过在发酵培养基中加入2 g/L氯化钙,并在45℃条件下烘干,不仅可以得到球形度好、大小均匀的微囊化屎肠球菌固态产品,而且其活菌数可以达到11.57 lgCFU/g。与游离屎肠球菌固态产品相比,微囊化屎肠球菌活菌制剂具有更强的耐受80℃高温及模拟胃肠液的能力(P<0.01),在常温条件下储存2个月,活菌数基本没有变化。【结论】微囊化屎肠球菌活菌制剂的发酵前包被制备工艺简单、产品形态较好、抗逆性强、稳定性高,且具有较高的包埋率,可以作为饲用高活性微生态制剂应用于生产实际。

[Objective] The research prepared and studied probiotics of new microencapsulated Enterococcus faecium. [Method] In this paper,we microencapsulated Enterococcus faecium using coating tech nology before fermentation,collected them by filtration technology,cultured in MRS medium adding suitable concentration of anhydrous calcium chloride, dried under the condition of 45 ℃ and got solid microen capsulated Enterococcus faecium products. And their tolerance abilities to the 80℃ temperature and the artificial gastric and intestinal fluids were evaluated in viable plate counts. [Result] The viable bacteria counts of liquid microencapsulated Enterococcus faecium products using coating technology before fermentation increased by 2 lgCFU/mL,more than that after fermentation. We could not only get both moderate sizes and ideal morphology products,but also high viable bacteria counts of 11.57 lgCFU/g by culturing in MRS adding 2 g/L anhydrous calcium chloride and drying for 5 h under the condition of 45 ℃ in electric blastdrying oven. Studies on using 80 ℃ temperature and the artificial gastric and intestinal fluids showed that the solid microencapsulated Enterococcus jaecium products could survive better than free Enterococcus Jaecium products（P〈0.01）. The experiment of storage at room temperature showed that there was no notable decline concerning the number of live bacteria. [Conclusion] Therefore, the simple technology and the products of ideal morphology, strong stress resistance, good stability and high yield would be beneficial for the development of new microbial ecological agents with high activity that can be used widely in feedstuffs.