The contamination of street vended vegetables may occur through the usage of manure and
contaminated irrigation water, and the consumption of these vegetables, such as ready-to-eat
salads, can cause foodborne diseases in consumers. The objective of this study was to investigate
the Enterobacteriaceae diversity in vegetables sold at informal markets in the Johannesburg
Metropolis. A total of 201 vegetable samples were purchased from randomly selected street
vendors from different regions in the Johannesburg Metropolis and analysed for aerobic growth
count and Enterobacteriaceae contamination using Plate Count Agar (PCA), and violet red bile
glucose agar (VRBGA), respectively. The diversity of bacterial isolates was analysed using
sequencing and phylogenetic analysis. The aerobic bacterial growth counts of vegetables from all
the regions ranged from 7.66(±0.759) to 8.37(±0.347) log10 cfu/g and the mean aerobic growth
counts of vegetables from Soweto and Yeoville were significantly different (p ≤ 0.05) from those
of the other regions, but were not significantly (p > 0.05) different across different vegetable
types. The Enterobacteriaceae growth counts in vegetables from all the regions ranged from 5.05
(±0.647) to 5.45 (±0.693) log10 cfu/g. The mean Enterobacteriaceae growth counts of vegetables were not significantly (p > 0.05) across each region and different vegetables types. The
predominant Enterobacteria genera were Serratia (35%), followed by Hafnia (21%), Aeromonas
(17%), and Pseudomonas (5%). In conclusion, this study shows that the vegetables sold at the
informal markets in the Johannesburg Metropolis have high aerobic bacterial growth and
Enterobacteriaceae contamination due to poor hygiene practices. The dominant
Enterobacteriaceae genera isolated are Aeromonas, Hafnia, Serratia, and Pseudomonas, which could be opportunistic pathogens. It is recommended that the Department of Health improves
vending and sanitation facilities, to prevent cross contamination. / Life and Consumer Sciences / M. Sc. (Life Sciences)
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:unisa/oai:uir.unisa.ac.za:10500/26491 |
| Date | 06 1900 |
| Creators | Ndlovu, Sihle |
| Contributors | Tabit, F. T., Ramganesh, S. |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Dissertation |
| Format | 1 online resource (xv, 70 leaves) : color illustrations, color graphs, color map, application/pdf |
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