黑果枸杞酵素中乳酸菌和酵母菌的分离鉴定和安全性评价

Identification and safety evaluation of lactic acid bacteria and yeast in Lycium ruthenicum Murr.jiaosu

目的对黑果枸杞酵素中乳酸菌和酵母菌进行分离鉴定,并对其安全性进行评价。方法采用形态学观察、16S rDNA、26S rDNA与内部转录间隔区(internal transcribed spacers,ITS)全序列分析分离鉴定自然发酵黑果枸杞酵素中的乳酸菌和酵母菌,并对其安全性进行评价,包括药敏试验、溶血试验和急性毒性试验。结果从酵素中分离得到了3株菌株分别为类食品乳杆菌(Lactobacillus paralimentarius)(M4),植物乳杆菌(Lactobacillus plantarum)(M6)和库德里阿兹威毕赤氏酵母菌(Pichia kudriavzevii)(Y5)。2株乳酸菌对青霉素类、头孢类、β-内酰胺类、大环内酯类及四环素类等大多数常见抗生素无耐药性;酵母菌Y5除了对氟康唑表现为耐药外,对其余抗真菌类抗生素均未表现出耐药性。3株菌均无急性毒性,也未发现有溶血现象。结论本研究初步验证了菌株的安全性,为3株菌在黑果枸杞酵素产品的研发与生产中的应用提供了基础研究数据。

Objective To isolate and identify lactic acid bacteria and yeast from Lycium ruthenicum Murr.jiaosu,and to evaluate its safety.Methods Lactic acid bacteria and yeast were isolated and identified from jiaosu in naturally fermentation of Lycium ruthenicum Murr.by morphological observation,16 S rDNA,26 S rDNA and internal transcribed spacers(ITS)full sequence analysis.Meanwhile,the safety was evaluated by susceptibility test,hemolytic test and acute toxicity experiment.Results Three strains were isolated from the jiaosu such as Lactobacillus parallelarius(M4),Lactobacillus plantarum(M6)and Pichia kudriavzevii(Y5).Two strains of lactic acid bacteria were sensitive to most common antibiotics such as penicillin,cephalosporin,β-lactams,macrolides and tetracyclines;yeast Y5 showed resistance to fluconazole but sensitivity to other antifungal antibiotics.None of the 3 strains had acute toxicity and hemolytic.Conclusion This study preliminarily verifies the safety of the strains,and provides basic research data for the application of the 3 strains in the development and production of Lycium ruthenicum Murr.jiaosu products.