乳酸菌CICC 6282的鉴定、生物学特性及其在发酵辣椒中的应用

Identification, biological characteristics, and its application in fermented chili of strain CICC 6282

该研究以分离自新疆发酵辣椒中的乳酸菌CICC 6282为研究对象,采用形态观察、生理生化试验及分子生物学技术对其进行菌种鉴定,从耐盐耐酸能力、抑菌活性、生长状况、产酸能力、亚硝酸盐降解能力和氨基酸脱羧酶活性等方面全面表征其生物学特性,并通过强化接种实验评价该菌株在发酵辣椒中的发酵特性。结果表明,菌株CICC 6282被鉴定为耐乙醇片球菌(Pediococcus ethanolidurans),能够耐受8%NaCl和pH 4.0的环境,具有亚硝酸盐降解能力,精氨酸双水解酶、赖氨酸脱羧酶和鸟氨酸脱羧酶活性均为阴性,发酵上清液能够抑制大肠埃希氏菌(Escherichia coli)的生长。与自然发酵辣椒相比,接种菌株CICC 6282发酵辣椒的总酸含量(5.53 g/kg)升高,亚硝酸盐含量(0.71 mg/kg)及生物胺总量(84.29 mg/kg)降低,且未检测到尸胺、腐胺、苯乙胺,说明菌株CICC 6282具有良好的发酵特性,能提高发酵辣椒的安全性,具有应用于辣椒发酵的潜力。

Using the lactic acid bacterium CICC 6282 isolated from fermented chili in Xinjiang as the research object,the strain was identified by morphological observation,physiological and biochemical tests,and molecular biology techniques,its biological characteristics were comprehensively characterized from the aspects of salt and acid tolerance,antibacterial activity,growth status,acid production capacity,nitrite degradation capacity and amino acid decarboxylase activity,and the fermentation characteristics of the strain in fermented chili were evaluated by enhanced inoculum experiments.The results showed that the strain CICC 6282 was identified as Pediococcus ethanolidurans,which was able to tolerate 8%NaCl and pH 4.0 environment,and had the ability of nitrite degradation,the arginine dihydrolase,lysine decarboxylase,and ornithine decarboxylase activities were negative,and the fermentation supernatant could inhibit the growth of Escherichia coli.Compared with naturally fermented chili,the total acid content(5.53 g/kg)of chili fermented with the strain CICC 6282 increased,the nitrite content(0.71 mg/kg)and the total biogenic amine content(84.29 mg/kg)decreased.In addition,putrescine,cadaverine,and phenylethylamine were not detected.These results indicated that the strain CICC 6282 had good fermentation characteristics,could improve the safety of fermented chili,and had the potential to be applied in the fermentation of chili.