黑曲霉菌标准物质的研制及其在食品检测中的应用

Preparation of standard materials for Aspergillus niger and its application on food detection

中文关键词:  黑曲霉菌  标准物质  转录间隔区位点

英文关键词:Aspergillus niger  standard materials  internal transcribed spacer sites

中文摘要:

      目的 研制黑曲霉菌标准物质, 并将其用于食品检测。方法 通过显微形态及转录间隔区(internal transcribed spacer, ITS)位点测序, 对研究用菌株进行菌种鉴定确认后冻干, 制备104 CFU/样品浓度的标准物质。通过对标准物质样品均匀性、运输稳定性、储藏稳定性以及在不同食品基质中使用效果的检验, 结合3家实验室的协作定值实验对黑曲霉菌标准物质样品进行评价。结果 CMCC98003经肉眼观察菌落绒状, 黑色孢子头, 菌落反面呈无色或淡黄色有皱褶。制片后显微镜下观察, 可见顶囊呈球形, 小梗, 大梗, 分生孢子粗糙, 分生孢子梗宽且光滑, 孢梗颈, 符合黑曲菌形态特性; ITS位点测序结果与美国国家生物信息中心基因库中已有序列比对, 匹配最优结果为黑曲霉菌。通过SPSS软件单因素方差分析结果为F0.05(19,20)=2.137, F=1.614

英文摘要:

      Objective To develop a standard substance with homogeneity and stability meeting the requirements of standard materials, and apply it to the quality control and laboratory examination of daily detection of Aspergillus niger in the laboratory. Methods The strains used in the study were identified by micromorphology and sequencing of internal transcribed spacer (ITS) sites, and then lyophilized to prepare 104 CFU/sample concentration standard material. Through the inspection of the uniformity, transportation stability, storage stability and the use effect in different food substrates of the reference material samples, combined with the cooperative fixed value experiment of 3 laboratories, the Aspergillus niger reference material samples were evaluated. Results The colony of CMCC98003 was fluffy and black spore head, the reverse side of the colony was colorless or light yellow with wrinkles. Under the microscope after production, it could be seen that the vesicle was spherical, small stem and large stem, the conidia was rough, the conidia stem was wide and smooth, and the spore stem neck conformed to the morphological characteristics of Aspergillus niger; the sequencing results of its loci were compared with the existing sequence alignment in the gene bank of the national biological information center of the United States, and the best matching result was Aspergillus niger. The results of one-way variance analysis by SPSS software were F0.05(19,20)=2.137, F=1.614