当前位置： SCI文献检索 > INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY期刊下所有文献 > Presence and survival of Escherichia coli O157:H7 on lettuce leaves and in soil treated with contaminated compost and irrigation water.

Presence and survival of Escherichia coli O157:H7 on lettuce leaves and in soil treated with contaminated compost and irrigation water.

Abstract：

:Escherichia coli O157:H7 outbreaks associated with produce consumption have brought attention to contaminated compost manure, and polluted irrigation water as potential sources of pathogens for the contamination of these crops. The aim of this study was to determine the potential transfer of E. coli O157:H7 from soil fertilized with contaminated compost or irrigated with contaminated water to edible parts of lettuce together with its persistence in soil under field conditions in two different seasons (fall and spring). Moreover, its survival on lettuce sprinkled with contaminated irrigation water was evaluated, as well as the prevalence of aerobic mesophilic, Enterobacteriaceae and Pseudomonadaceae in control lettuce samples. Four treatments, contaminated compost, surface and sprinkle irrigation with contaminated water and uninoculated pots, were used in this work. Contaminated compost was applied to soil in the pots before lettuce was transplanted and contaminated irrigation water was applied twice and three times on the plants after the seedlings were transplanted, for sprinkle and surface irrigation, respectively. E. coli O157:H7 survived in soil samples for 9 weeks at levels, 4.50 log cfu gdw(-1) (dw, dry weight) in fall and 1.50 log cfu gdw(-1) in spring. The pathogen survives better in fall, indicating an important influence of environmental factors. E. coli O157:H7 population in lettuce leaves after sprinkle irrigation was very high (between 10(3) and 10(6) cfu g(-1)), but decreased to undetectable levels at field conditions. There was also transfer of E. coli O157:H7 from soil contaminated with compost or irrigated with contaminated water to lettuce leaves, mainly to the outer ones. The mean counts for aerobic mesophilic, Enterobacteriaceae and Pseudomonadaceae populations were also influenced by environmental conditions; higher levels were observed under fall conditions than in spring conditions. Contamination of lettuce plants in the field can occur through both contaminated composted manure and irrigation water and persist for several months.

journal_name

Int J Food Microbiol

journal_title

International journal of food microbiology

authors

Oliveira M,Viñas I,Usall J,Anguera M,Abadias M

doi

10.1016/j.ijfoodmicro.2012.03.014

subject

Has Abstract

pub_date

2012-05-15 00:00:00

pages

133-40

issue

eissn

0168-1605

issn

1879-3460

pii

S0168-1605(12)00133-X

journal_volume

156

pub_type

杂志文章

在线工具

Presence and survival of Escherichia coli O157:H7 on lettuce leaves and in soil treated with contaminated compost and irrigation water.