3种乳酸菌鉴定、筛选、富硒比较研究

为了筛选耐硒、富硒能力强的乳酸菌,本实验通过对嗜热链球菌、保加利亚乳杆菌、嗜酸乳杆菌进行耐硒能力比较,并对耐硒能力最强的菌种进行富硒实验。通过采用分离纯化,结合糖酵解和革兰氏染色法对菌种进行鉴别,再对菌种进行驯化培养(所选用的培养基要形成浓度差)以及耐硒实验,利用3,3’-氨基联苯胺比色法测定硒转化能力,结果显示耐硒能力从大到小分别是嗜酸乳杆菌、嗜热链球菌、保加利亚杆菌；当含硒量为17μg/mL,37℃下培养9h,嗜酸乳杆菌富硒率达到65.4%,在含硒的培养基上观察发现嗜酸乳杆菌的菌落一般比较小,呈不规则圆形,乳白色,表面光滑,有光泽。

Identification, Screening and Selenium-enrichment Comparison of Three Kinds of Lactobacillus

To screen Lactobacillus with strong ability of selenium resistance and selenium enrichment, the selenium resistance of Streptococius thermopiles, Lactobacillus bulgaria, and Lactobacillus acidophilus is compared, and the selenium-enriched study is conducted on the strain with the strongest selenium resistance. The separation and purification, combined with glycolytic and Gram staining, was used to identify the strains, and then the strains were domesticated (the media should form the concentration differences). The 3,3'-aminobenzidine colorimetry was used to determine the selenium conversion. The results showed that the order of selenium tolerance was Lactobacillus acidophilus, Streptococius thermopiles and Lactobacillus bulgaria. When the selenium content was 17 μg/mL, the strains were cultivated for 9 h under 37℃, the selenium enrichment rate of Lactobacillus acidophilus reached 65.4%. Lactobacillus acidophilus colonies were generally found to be relatively small, irregularly rounded, milky white, smooth and shiny on selenium-containing media