Hünniger Tim, Felbinger Christine, Wessels Hauke, Mast Sophia, Hoffmann Antonia, Schefer Anna, Märtlbauer Erwin, Paschke-Kratzin Angelika, Fischer Markus
†Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
‡Lehrstuhl für Hygiene und Technologie der Milch, Tierärtzliche Fakultät, Ludwig-Maximilians-Universität, Schönleutnerstraße 8/219, 85764 Oberschleißheim, Germany.
J Agric Food Chem. 2015 May 6;63(17):4291-6. doi: 10.1021/acs.jafc.5b00874. Epub 2015 Apr 28.
Spore-forming Alicyclobacillus spp. are able to form metabolites that induce even in small amounts an antiseptical or medicinal off-flavor in fruit juices. Microbial contaminations could occur by endospores, which overcame the pasteurization process. The current detection method for Alicyclobacillus spp. can take up to 1 week because of microbiological enrichment. In a previous study, DNA aptamers were selected and characterized for an aptamer-driven rapid enrichment of Alicyclobacillus spp. spores from orange juice by magnetic separation. In the present work, a direct quantification assay for Alicyclobacillus spp. spores was developed to complete the two-step approach of enrichment and detection. After mechanical treatment of the spores, the isolated DNA was quantified in a real-time PCR-assay targeting 16S rDNA. The assay was evaluated by the performance requirements of the European Network of Genetically Modified Organisms Laboratories (ENGL). Hence, the presented method is applicable for direct spore detection from orange juice in connection with an enrichment step.
产芽孢的 Alicyclobacillus 属细菌能够形成代谢产物，即使含量很少也会在果汁中产生防腐或药用异味。微生物污染可能由芽孢引起，芽孢能耐受巴氏杀菌过程。目前检测 Alicyclobacillus 属细菌的方法由于微生物富集，可能需要长达 1 周的时间。在之前的一项研究中，筛选并鉴定了 DNA 适体，用于通过磁分离从橙汁中快速富集 Alicyclobacillus 属细菌的芽孢。在本研究中，开发了一种针对 Alicyclobacillus 属细菌芽孢的直接定量检测方法，以完善富集和检测的两步法。对芽孢进行机械处理后，通过靶向 16S rDNA 的实时 PCR 检测法对分离的 DNA 进行定量。该检测方法根据欧洲转基因生物实验室网络（ENGL）的性能要求进行了评估。因此，所提出的方法适用于结合富集步骤直接检测橙汁中的芽孢。
