白方腐乳中产胺细菌分离鉴定及产胺性能检测

Isolation,identification of biogenic amine-producing bacteria and their amine-producing characteristics in white sufu post-fermentation process

为了解白方腐乳生产过程中产胺菌类型及其产胺特性,从白方腐乳后发酵过程中分离获得8株产生物胺细菌,并对其产生物胺性能进行研究。然后,通过16S rDNA序列鉴定出拟蕈状芽孢杆菌(Bacillus paramycoides)4株,其余4株分别为热带芽孢杆菌(Bacillus tropicus)、屎肠球菌(Enterococcus faecium)、解淀粉芽孢杆菌(Bacillus amyloliquefaciens)和枯草芽孢杆菌(Bacillus subtilis)。采用超高效液相色谱法分析发现8个菌株产生物胺种类不同,但都具有产腐胺、尸胺和酪胺能力,其中产酪胺量最大(0.45~87.31 mg/L)。菌株S5产生物胺总量最高,达106.34 mg/L,其中酪胺量高达87.31 mg/L。菌株S5生物胺产生量随着温度(15~35℃)升高而增加,但在温度<15℃,乙醇体积分数>15%,氨基酸质量分数<0.5%,pH>7.5,NaCl质量分数>6.0%条件下总生物胺和酪胺的产生受到抑制。该研究结果可为控制腐乳生产过程生物胺的产生提供参考。

In order to explore the types of amine-producing bacteria and their characteristics,eight strains of biogenic amines-producing bacteria were isolated from white sufu post-fermentation process and their growth characteristics and ability to produce biogenic amines(BAs)were studied.Furthermore,the determination of 16S rDNA of eight strains showed that the four strains were identified to be Bacillus paramycoides and others were found to be Bacillus tropicus,Enterococcus faecium,Bacillus amyloliquefaciens,and Bacillus subtilis.The BAs in the fermentation broth of these strains were detected and analyzed by ultra performance liquid chromatography(UPLC).The results indicated that they produced different kinds of BAs.All strains had the ability to produce putrescine,cadaverine and tyramine,of which the content of tyramine was the highest,ranging from 0.45 to 87.31 mg/L.Among them,Enterococcus faecium S5 produced the largest amount of total BAs(106.34 mg/L)and tyramine(87.31 mg/L).Moreover,amine-producing characteristics of strain S5 were analyzed,indicating that the content of total BAs increased with the increase of temperature(15-35℃),but total BAs and tyramine production can be inhibited under given conditions(temperature<15℃,or alcohol volumn fraction>15%,or mass fraction of amine acids<0.5%,or pH>7.5,or mass fraction of NaCl>6.0%).The present study provides reference for controlling the production of BAs during sufu post-fermentation process.