结合平板计数与宏基因组学研究方法分析气调保鲜卤鸭掌中微生物污染

Analysis of microbial contamination in modified atmosphere preservation bittern duck feet based on aerobit plate count and metagenomics

中文关键词:  气调保鲜卤鸭掌  宏基因组  菌相组成

英文关键词:modified atmosphere preservation bittern duck feet  metagenomics  microbial composition

中文摘要:

      目的 研究气调保鲜卤鸭掌中微生物污染的菌相组成及主要致病菌、致病基因与耐药基因的相关情况。方法 从市场采购气调保鲜鸭掌样品, 提取DNA, 检测DNA浓度, 测序、注释, 菌种鉴定与丰度分析等, 并检验菌落总数。结果 菌落总数结果为1200 CFU/g, 符合食品安全国家标准要求, DNA浓度为6.54 ng/μL, 存在一定程度微生物污染; 采用宏基因组研究方法分析菌相组成, 共测出48种微生物, 诺卡氏菌丰度最高, 约75.7%, 大肠杆菌、不动杆菌、慢生根瘤菌、盐单胞菌、克雷伯菌、沙门氏菌、弧菌丰度大于1%; 比对SEED数据库, 检出对稳态铜的抗性基因; 比对KEGG数据库, 发现13种代谢通路可感染宿主; 比对ARBD数据库, 发现4个多重耐药性基因, 1个氯霉素抗性基因。结论 宏基因组结合传统微生物研究方法可有效分析样品中微生物状况, 并能从分子层面研究致病因子, 以及耐药基因的传播机理, 对于微生物污染防控, 耐药基因传播阻断机制, 有重要的借鉴性意义。

英文摘要:

      Objective To study the microflora composition of microbial contamination in bittern duck palms preserved by modified atmosphere and the correlation between the main pathogenic bacteria, pathogenic genes and drug resistance genes. Methods Samples of modified atmosphere preserved duck feet were purchased from the market, DNA was extracted, DNA concentration was detected, sequencing, annotation, strain identification and abundance analysis were carried out, and the total number of colonies was tested. Results The total number of colonies was 1200 CFU/g, which met the requirements of national food safety standards. The DNA concentration was 6.54 ng/μL, and there was a certain degree of microbial pollution. Using metagenomic research methods to analyze microbial composition, a total of 48 microorganisms were identified, with Nocardia having the highest abundance of about 75.7%, and Escherichia coli, Acinetobacter, Clostridium, Halomonas, Klebsiella, Salmonella, and Vibrio having an abundance greater than 1%. Compare the SEED database to detect resistance genes to steady-state copper; comparing with the KEGG database, it was found that 13 kinds of metabolic pathways can infect the host; comparing with the ARBD database, 4 multidrug-resistant genes and 1 chloramphenicol resistance gene were found. Conclusion The combination of metagenomics and traditional microbial research methods can effectively analyze the microbial status in samples, and can study the pathogenic factor mechanism and the transmission mechanism of drug resistance genes at the molecular level. This has important reference significance for studying microbial pollution prevention and control, as well as the transmission blocking mechanism of drug resistance genes.