Abstract
Our previous study reported that fresh produce grown in aquaponic and hydroponic systems can pose potential food safety hazards due to an accidental introduction of contaminated fish and cross-contamination between the systems. In this study, we examined the effects of plant species and age on the likelihood and level of internalization of Shiga toxin-producing Escherichia coli (STEC) in aquaponic and hydroponic systems. Four plant species, basil (Ocimum basilicum L. cv. Genovese), cilantro (Coriandrum Sativum L.), lettuce (Lactuca sativa cv. Cherokee), and kale (Brassica oleracea var. sabellica), received root damage treatment as seedlings before transplanting or mature plants at three weeks after transplanting by cutting off 1-cm tips of one-third of the roots. Enrichments and selective media were used for the isolation, and presumptive positive colonies were confirmed by PCR for the presence of stx1 gene in plant tissues, recirculating water, and fish feces collected at four weeks after transplanting. In hydroponic systems, STEC was found neither in the solution nor in the roots and leaves of all four plant species, possibly through improved sanitation and hygiene practices. However, consistent with our previous findings, STEC was found in the water, on the plant roots, and in the fish feces in aquaponic systems, even after thorough sanitation prior to the study. Regardless of plant age, STEC was internalized in the roots of all plant species when the roots were damaged, but there was no difference in the degree of internalization with STEC among plant species. STEC was present in the leaves only when seedlings received root damage treatment and were grown to maturity, indicating that root damage allows STEC to internalize in the roots within a week, but a longer period is required for STEC to internalize into the leaves. We concluded that root damage on seedlings can cause the internalization of E. coli O157:H7 in the edible parts of leafy vegetables and herbs in soilless production systems.
Highlights
The global food demand and security have been increased with the increasing population [1]
A high level of nutrients is ideal for bacterial growth; the viability of E. coli O157:H7 increases in nutrient-rich soils and hydroponics [49,50,51]
Contamination with Shiga toxin-producing Escherichia coli (STEC) can be eliminated in hydroponic systems if the entire system is thoroughly sanitized before each use
Summary
The global food demand and security have been increased with the increasing population [1]. 10.8% of people worldwide suffered from undernourishment in 2018, and Sub-Saharan. Africa experienced a sharp increase of undernourishment from 20.6% in 2015 to 22.8% in. Facing the challenge of food demand, the urban farming fulfilled 37% of vegetable needs in Kathmandu, Nepal, 45% of local food needs in Hong Kong, and almost 60% of all. Cuban vegetable demands [3,4,5]. It is a potential way to feed urban residents in the world with fresh produce [6]. Nearly 48% of foodborne outbreaks are linked to the consumption of fresh fruits and vegetables due to the bacterial contamination of fresh produce [7,8].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
