豇豆泡菜中产生物胺菌株的筛选鉴定及其产胺特性研究

Screening and identification of biogenic amines producing strains in cowpea pickle and their biogenic amines producing characteristics

传统四川泡菜在发酵过程中由于部分微生物代谢作用而产生的生物胺对人体有毒害作用,为探究泡菜中主要产胺微生物种类及其产胺特性,以自然发酵和卤水发酵豇豆泡菜为原料,在不同发酵时期进行取样,以氨基酸肉汤培养基作为选择培养基对产胺菌株进行筛选,利用高效液相色谱对其产胺能力进行定量分析,挑选出高产胺菌株,探究其在不同环境(pH、盐度、温度)下的产胺能力。共筛得26株产胺菌株,经16S rRNA基因测序技术鉴定为8个属,包括肠杆菌属、克雷伯氏菌属、勒克氏菌属、假柠檬酸盐杆菌属、莱略特菌属、泛菌属、魏斯氏菌属和乳杆菌属,其中肠杆菌科菌株具有很强的产胺能力,总产胺量最高为7400.13 mg/L,主要产胺种类为腐胺和尸胺。温度对于菌株产胺能力的影响相对较小,而pH和盐度对菌株产胺能力有明显的影响,当pH值低至3.5、盐度高达80 g/L时,菌株的产胺能力受到强烈抑制。研究结果可为控制泡菜中产胺微生物生长,降低生物胺积累提供理论参考。

The biogenic amines(BAs)produced by some microorganisms during the fermentation of traditional Sichuan pickles are toxic to human beings.In order to study the main kinds of BA-producing microorganisms and their BA-producing characteristics,natural fermentation and brine fermentation of cowpea pickle were used as experimental materials,samples were taken at different fermentation periods,and the amino acids broth medium was used as the selective medium to screen BA-producing strains,HPLC was used to quantitatively analyze its BA-producing capacity,and the high BA-producing strains were selected to explore their BA-producing capacity under different environments(pH,salinity,temperature).The results showed that 26 strains of amines-producing bacteria were screened and identified as 8 genera by 16S rRNA gene sequencing,including Enterobacter sp.,Klebsiella sp.,Leclercia sp.,Pseudocitrobacter sp.,Lelliottia sp.,Pantoea sp.,Weissella sp.and Lactiplantibacillus sp.Among them,Enterobacteriaceae strains had strong BA-producing capacity,with the highest total BAs production of 7400.13 mg/L,and the main types of BA were putrescine and cadaverine.The effect of temperature on the ability of BA-producing was relatively small,but the effect of pH and salinity on the ability of BA-producing was obvious.When pH was as low as 3.5 and salinity was as high as 80 g/L,the BA-producing capacity of the strains was strongly inhibited.The results provided some theoretical reference for controlling the growth of BA-producing microorganisms and reducing the accumulation of BAs in pickles.