Weiss Alexander, Hertel Christian, Grothe Silke, Ha Diep, Hammes Walter P
Institute of Food Technology, University of Hohenheim, Stuttgart, Germany.
Syst Appl Microbiol. 2007 Sep;30(6):483-93. doi: 10.1016/j.syapm.2007.03.006. Epub 2007 May 18.
The microbiota of ten seeds and ready-to-eat sprouts produced thereof was characterized by bacteriological culture and denaturing gradient gel electrophoresis (DGGE) of amplified DNA fragments of the 16S rRNA gene. The predominant bacterial biota of hydroponically grown sprouts mainly consisted of enterobacteria, pseudomonades and lactic acid bacteria (LAB). For adzuki, alfalfa, mung bean, radish, sesame and wheat, the ratio of these bacterial groups changed strongly in the course of germination, whereas for broccoli, red cabbage, rye and green pea the ratio remained unchanged. Within the pseudomonades, Pseudomonas gesardii and Pseudomonas putida have been isolated and strains of the potentially pathogenic species Enterobacter cancerogenes and Pantoea agglomerans were found as part of the main microbiota on hydroponically grown sprouts. In addition to the microbiota of the whole seedlings, the microbiota of root, hypocotyl and seed leafs were examined for alfalfa, radish and mung bean sprouts. The highest and lowest total counts for aerobic bacteria were found on seed leafs and hypocotyls, respectively. On the other hand, the highest numbers for LAB on sprouts were found on the hypocotyl. When sprouting occurred under the agricultural conditions, e.g. in soil, the dominating microbiota changed from enterobacteria to pseudomonades for mung beans and alfalfa sprouts. No pathogenic enterobacteria have been isolated from these sprout types. Within the pseudomonades group, Pseudomonas jessenii and Pseudomonas brassicacearum were found as dominating species on all seedling parts from soil samples. In practical experiments, a strain of P. jessenii was found to exhibit a potential for use as protective culture, as it suppresses the growth of pathogenic enterobacteria on ready-to-eat sprouts.
通过对16S rRNA基因扩增DNA片段进行细菌培养和变性梯度凝胶电泳（DGGE），对10种种子及其制成的即食豆芽的微生物群进行了表征。水培豆芽的主要细菌生物群主要由肠杆菌、假单胞菌和乳酸菌（LAB）组成。对于小豆、苜蓿、绿豆、萝卜、芝麻和小麦，这些细菌群的比例在发芽过程中变化很大，而对于西兰花、红甘蓝、黑麦和青豆，该比例保持不变。在假单胞菌中，已分离出杰氏假单胞菌和恶臭假单胞菌，并且在水培豆芽的主要微生物群中发现了潜在致病物种致癌肠杆菌和成团泛菌的菌株。除了整个幼苗的微生物群外，还对苜蓿、萝卜和绿豆芽的根、下胚轴和子叶的微生物群进行了检测。需氧菌的总数最高和最低分别出现在子叶和下胚轴上。另一方面，豆芽上乳酸菌数量最多的部位是下胚轴。当在农业条件下（例如在土壤中）发芽时，绿豆和苜蓿芽的主要微生物群从肠杆菌变为假单胞菌。从这些豆芽类型中未分离出致病性肠杆菌。在假单胞菌组中，耶氏假单胞菌和芸苔假单胞菌是土壤样本中所有幼苗部位的优势种。在实际实验中，发现一株耶氏假单胞菌具有用作保护性培养物的潜力，因为它能抑制即食豆芽上致病肠杆菌的生长。
