乳酸菌中生物胺氧化酶菌株的筛选

为获得良好的具有生物胺降解能力的肉品发酵剂，本文以实验室前期筛选的63株乳酸菌作为研究对象，利用双层显色平板试验，氧化酶试验和高效液相色谱检测对产生物胺氧化酶菌进行筛选，并对所筛选的菌株做抑菌试验和耐盐耐亚硝酸盐等试验。结果表明：本次实验筛选出4株（1株Pediococcus acidilactici，1株Pediococcus pentosaceus，2株Lactobacillus plantarum）具有较强生物胺氧化能力的乳酸菌，其中以乳酸片球菌（Pediococcus acidilactici）的生物胺降解能力最好，其对苯乙胺、色胺、组胺、腐胺、尸胺、酪胺、亚精胺和精胺的降解率分别为56.71%、51.40%、40.86%、28.12%、18.92%、24.59%、18.20%和9.68%。通过抑菌试验和耐盐耐亚硝酸盐等试验发现乳酸片球菌对致病性大肠杆菌，单增李斯特菌，金黄色葡萄球菌具有良好抑菌效果，且耐盐能力在6%以上，耐亚硝酸盐能力在0.15 g/kg以上，最适温度为37 ℃，最适pH为6.5。
In order to obtain starters that can degrade biogenic amines for meat products, 63 strains of lactic acid bacteria previously screened in the laboratory were used as study objects, and the biogenic amine oxidase-producing strains were screened using a color development method on a double-layered plate, the oxidase test, and high-performance liquid chromatography. The bacteriostatic, salt tolerance, and nitrite tolerance tests were conducted for isolated strains. The results showed that the four strains, including one Pediococcus acidilactici strain, one Pediococcus pentosaceus strain, and two Lactobacillus plantarum strains, screened in this experiment, were lactic acid bacteria showing a strong capacity to oxidize biogenic amines. Among the strains, P. acidilactici exhibited the highest biogenic amine degradation, with degradation rates for phenylethylamine, tryptamine, histamine, putrescine, cadaverine, tyramine, spermidine, and spermine of 56.7%, 51.40%, 40.86%, 28.12%, 18.92%, 24.59%, 18.20, and 9.68%, respectively. The results from the bacteriostatic, salt tolerance, and nitrite tolerance tests suggested that P. acidilactici inhibited Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus, with a salt tolerance greater than 6% and a nitrite tolerance greater than 0.15 g/kg; the optimum temperature and pH were 37 ℃ and 6.5, respectively.