Elucidation of the mechanism for microbial contamination of produce by agricultural water and pesticide solutions

研究代表者publisher研究種目：挑戦的萌芽研究; 研究期間：2012～2014; 課題番号：24658033; 研究分野：食品保全学; 科研費の分科・細目：研究成果の概要（和文): 青果物の栽培中の潜在的汚染源として, 農業用水に加えて, 農業用水に希釈・溶解した農薬溶液も重要であり, それらから青果物への微生物汚染の機構解明が望まれる. 農業用水あるいは農薬溶液から青果物に移行する細菌および糸状菌はそれぞれ10菌種以上存在し, それらの青果物汚染微生物に加えて, Escherichia coli O157: H7（毒素陰性株）も, 数種農薬溶液中で増殖することが明らかとなった. 増殖を示したこれらの微生物は, ペクチン分解性を有する植物病原菌のように, 細胞壁分解酵素を産生しなかったため, 農業用水および農薬溶液から移行しても, 青果物内部には侵入せずに表面に付着の状態で存在すると推定された. 研究成果の概要（英文): Pesticide solutions diluted with agricultural water are potential sources of preharvest microbial contamination for produce as well as agricultural water itself. The invasion of microorganisms from both agricultural water and pesticide solutions were investigated. Several spoilage pathogens that were transferred from the agricultural water and pesticide solutions to produce and Escherichia coli O157: H7, representing a human pathogen, proliferated when inoculated with pesticide products. Because these microorganisms did not produce cell wall degrading enzymes unlike pectinolytic bacteria and fungi, the cross-contaminating microbes including E. coli O157: H7 from agricultural water and pesticide solutions were assumed to persist on the surface of the produce and not infect inside the produce