为获得鹿源肠道菌群中的芽孢杆菌并研究其益生作用,对梅花鹿肠道分泌物85℃水浴处理15min以筛选芽孢杆菌.根据菌落形态、生理生化特征及分子生物学结果进行鉴定,通过抑菌试验、耐酸、耐胆盐试验及产纤维素酶试验等方法对其生物学特性进行研究.结果表明:试验共分离出4株芽孢杆菌,分别编号为XF-1、XF-2、XF-3、XF-4,对其中的两株进行鉴定,最终确定XF-1为地衣芽孢杆菌,XF-3为解淀粉芽孢杆菌.采用牛津杯法研究两株芽孢杆菌对4种致病菌的抑制作用,发现XF-1对大肠杆菌、链球菌、沙门氏菌都具有良好的抑制作用,XF-3对大肠杆菌、金黄色葡萄球菌、链球菌、沙门氏菌都具有良好的抑制作用.选择CMC-Na培养基检测这两株芽孢杆菌的产纤维素酶能力,试验表明,菌株XF-1的纤维素降解指标为D/d=2.18,菌株XF-3纤维素降解指标为D/d=3.18,XF-3的降解纤维素能力高于XF-1.试验中计算在不同酸性环境和胆盐环境中菌株的成活率,评价耐受能力的差异,结果表明:XF-1在pH值3.0环境中24h存活率是7.3%,在0.2%胆盐环境中24h存活率为8.57%,可产纤维素酶;XF-3在pH值3.0环境中24h存活率是12.5%,在0.2%胆盐环境中24h存活率为6.67%,可产纤维素酶.试验结果证明这两株芽孢杆菌有一定的抗逆性和益生能力,具有作为益生菌研究开发的潜力.%In order to obtain the Bacillus in the intestinal flora of deer and study its beneficial effects, intestinal secretion of Sika Deer was processed with 85℃ water-curing treatment for 15 min, and Bacillus were screened. Bacillus was identified according to the colony morphology, physiological and biochemical characteristics and molecular biological results. The biological characteristics were studied by the methods of antibacterial test, acid resistance, salt tolerance test and cellulase production test. Results showed that four strains of Bacillus were isolated from the experiment, named XF-1, XF-2, XF-3 and XF-4. Two of them were identified, XF-1 was Bacillus licheniformis and XF-3 was Bacillus amyloliquefaciens. The inhibitory effect of two strains of Bacillus on the four pathogenic bacteria of was studied by using the Oxford cup method. XF-1 had a good inhibitory effect on Escherichia coli, Streptococcus and Salmonella; XF-3 had a good inhibitory effect on Escherichia coli, Staphylococcus aureus, Streptococcus, Salmonella. CMC-Na medium was used to detect the cellulase producing ability of two strains of Bacillus. The cellulose degradation index of strain XF-1 was D/d=2.18, the cellulose degradation index of strain XF-3 was D/d=3.18, and the cellulose degrading capacity of XF-3 was higher than XF-1.In the experiment, the survival rate of bacteria in different acid environment and bile salt environment was calculated, and the difference of tolerance was evaluated. The results were indicated that after 24h,the survival rate of XF-1 in the pH 3.0 environment was 7.3%, the survival rate was 8.57% in the 0.2% bile salt environment. Cellulase was produced after 24h, the survival rate of XF-3 in the pH 3.0 environment was 12.5%, the survival rate was 6.67% in the 0.2% bile salt environment. The results showed that the two strains had a certain degree of resistance and probiotic ability. They had been used for research and development as probiotics.
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