期刊
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
卷 257, 期 -, 页码 192-200出版社
ELSEVIER
DOI: 10.1016/j.ijfoodmicro.2017.06.020
关键词
Aquatic compartments; Antibiotic resistance; Vegetables contamination; Irrigation water; Escherichia colt
资金
- National Funds from FCT Fundacao para a Ciencia e a Tecnologia [JPI/0002/2013]
- FCT [UID/AMB/50017/2013 - POCI-01-0145-FEDER-007638]
- Artur Alves (FCT Investigator Programme) [IF/00492/2013]
- Isabel Henriques (FCT Investigator Programme) [IF/00492/2013]
- Marta Tacao [SFRH/BPD/114855/2016]
- Susana Aratijo [SFRH/BD/52573/2014]
- Fundação para a Ciência e a Tecnologia [SFRH/BPD/114855/2016] Funding Source: FCT
This study aimed to characterize Escherichia coli present in irrigation water and vegetables from 16 household farms. Isolates were obtained from 50% of water (n = 210 isolates) and 38% of vegetable samples (n = 239). Phylogroups B1 (56% of isolates) and A (22%) were the most prevalent both in water and vegetables. Diarrheagenic strains were detected in vegetables. Irrespective of the source (i.e. water or vegetables), the most common antibiotic resistance was against streptomycin (89% resistant isolates) and tetracycline (24%). Common acquired genes (e.g. blar(TEM), tetA, tetB) were found in isolates from both sources. Class I integrons were detected in water (arrays dfrA1-aadA1 and dfr16-blaPlb-aadA2-ereA) and vegetables (unknown arrays). intI2 was detected in water (dfrA1-sat2-aadA1). Plasmids were detected in 14 isolates (IncFIC, IncFIB, IncFrep, Inch in both samples; IncY in vegetables). Plasmids from seven isolates were transferrable by conjugation, conferring resistance to antibiotics to the recipient strain. Multidrug-resistant (MDR) strains were isolated from water (12% of the unique isolates) and vegetables (21%). Predominant sequence types (STs) among MDR isolates were ST10, ST297 and ST2522. In some cases, the same STs and identical clones (as showed by rep-PCR typing) were detected in water and vegetables, suggesting cross-contamination. This study identified several risk factors in E. coil isolates from vegetables and irrigation water, raising health concerns. Also, results suggest that irrigation groundwater constitutes a source of E. coli that may enter the food chain through vegetables ingestion.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据