复合乳酸菌制剂的耐受性和抑菌性研究

Study on tolerance and bacteriostatic activity of compound Lactobacillus preparation

本试验将四株饲用乳酸菌,制成复合乳酸菌制剂,通过单因素试验设计,以存活率为指标,研究复合微生态产品对高温、酸、胆盐的耐受性,采用琼脂稀释法、牛津杯法分别测定复合乳酸菌制剂对不同种类饲用抗生素的耐受性及对致病菌的抑制作用。结果表明:复合乳酸菌产品在温度65℃处理2.5、5、7.5 min以及85℃处理2.5 min对其存活率没有影响,但当85℃处理5 min,存活率下降至48%;p H为3时处理90 min存活率高达80.54%。对0.3%猪胆盐的耐受性较好,处理1 h存活率为73.52%;对抗生素(药物饲料添加剂)杆菌肽锌、亚甲基水杨酸杆菌肽耐受性最强,对吉他霉素的耐受性最差;可抑制致病菌株大肠埃希氏菌的生长。体外评价试验结果表明,复合乳酸菌制剂具有很好的益生特性,可进一步研究其在动物上的应用效果。

In this experiment,four strains Lactic acid bacteria were made into compounded Lactobacillus preparation.The survival rate was used as the evaluation indexes,the in vitro probiotic effects of heat resistance,acid resistance,salt tolerance and bacteriostatic ability,antibiotic resistance were evaluated by single factor test.The results showed that the survival rate reached over 96%under the treatment at the temperature of 65℃for 2.5,5,7.5 min,85℃for 2.5 min.But it decreased to 48%when the temperature was increased to 85℃for 5 min.The survival rate reached over 80%under the treatment at the pH of 3 for 90 min.Compound Lactobacillus preparation had the ability to tolerance of 0.3%pig bile salt,the survival rate reached 73.52%for 1 h.The compound Lactobacillus preparation has the strongest tolerance to the bacitracin zinc and bacitracin methyleue disalicylate,and the worst tolerance to kitasamycin;The compound Lactobacillus preparation could inhibit the growth of pathogenic strain Escherichia coli.The vitro probiotic effect indicated that compound Lactobacillus preparation has probiotic properties and good application value.