应用聚合酶链式反应-变性梯度凝胶电泳和 16S rDNA技术分析果冻胀气原因

目的分析某品牌果冻胀气的原因。方法提取胀气果冻总DNA,采用聚合酶链式反应-变性度凝胶电泳技术(polymerase chain reaction-denaturing gradient gel electrophoresis,PCR-DGGE)进行菌群结构分析,同时采用平板分离法从果冻中分离细菌。并将分离得到的菌株进行16S rDNA扩增和测序比对分析。将分离的菌株接种到正常果冻中进行产气实验。结果 PCR-DGGE和平板分离结果表明,在胀气果冻中分别只检测到一种细菌,未检测出真菌。测序比对结果表明该细菌属于芽孢乳杆菌属。将该菌接种到正常果冻中会引起果冻胀气。结论芽孢乳杆菌是导致该品牌果冻胀气的主要因素。

Analysis of swollen jelly by polymerase chain reaction-denaturing gradient gel electrophoresis and 16S rDNA techniques

Objective To analyze the reason of swollen brand jelly. Method Total microbial community genome were extracted from swollen and normal jelly and analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Bacteria was isolated by traditional plate technique and the 16S rDNA of isolated bacteria was amplified and sequenced. Observation the production of gas by inoculating the isolated strain into normal jelly. Result Both the DGGE profile and plate technique result revealed that only one species of bacteria could be detected, fungus was not detected. The result of sequence blasting showed that the strain fell within the genus Sporolactobacillus. The strain resulted in production of gas when it was inoculated into normal jelly and cultivated for 7 d. Conclusion The result indicated that Sporolactobacillus played the key role in the swollen brand jelly.