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The purpose of this paper is to assess the occurrence of the extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamase genes in 144 Escherichia coli isolates recovered from 160 vegetable salad samples.

Among the 144 E. coli isolates recovered from 160 vegetable salads, 17 (12 percent) ceftazidime-resistant isolates were screened for ESBL production with the double disk-diffusion test. The ESBL-producing isolates were characterized for antimicrobial resistance, the presence of virulence genes and plasmid-mediated quinolone resistance (PMQR) determinants. The isolates were also subjected to phylogenetic group typing. The existence of plasmid AmpC genes and mutations in the regulatory region of the chromosomal AmpC gene was assessed using polymerase chain reaction (PCR) and sequencing. All β-lactamase isolates were further characterized by pulsed-field gel electrophoresis to determine the genetic relatedness.

Overall, 17 (12 percent) of the 144 E. coli isolates studied were ceftazidime resistant. Among the 17 isolates, 13 (77 percent) were multidrug resistant and four (23.5 percent) were ESBL producers. The bla CTX-M14 was the only gene detected. Of the 12 AmpC-producing isolates, three (18 percent) harbored plasmid-encoded AmpC and sequencing analysis of the chromosomal AmpC genes revealed mutations in the promoter/attenuator region. PMQR determinants were detected in 9 (52 percent) isolates. A was the most prevalent phylogenetic group (56 percent), followed by groups B1 (31 percent), D (6 percent), and B2 (6 percent). PCR showed that six (50 percent) ESBL/AmpC-producing E. coli isolates carried one and/or two virulence genes. Pulsed-field gel electrophoresis showed no epidemiological relationship between these isolates.

This study places vegetable salads within the spectrum of ecological niches that may be vehicles for antibiotic-resistant bacteria/genes with clinical interest and these findings are worthy of attention as their spread to humans by ingestion cannot be dismissed.

Against a milieu of fragmented research that documents indigenous practices related to food security, and the heterogeneous settings from which the studies have been conducted, this study aims to synthesize the evidence of indigenous knowledge-food security nexus to strengthen the call for the revitalization of indigenous knowledge (IK) as part of the mechanisms to manage food security challenges being aggravated by climate change.

Drawing on insights from sub-Saharan Africa (SSA), this study reviews 122 articles accessed from the Web of Science and Scopus databases, which covered indigenous methods used for producing, gathering, processing, preserving and storing diverse food sources that indigenous people deploy in securing their food systems.

The surge in attention to focus on IK-food security nexus tends to be influenced by the growing acknowledgement of climate change impacts on food systems. Essentially, the IK-based practices adopted address all the four food security pillars that are specified by the Food and Agricultural Organization (FAO) as availability, accessibility, utilization and stability. The main motivation behind the continued use of IK-based ways relates largely to the interest to be food secure against climatic shocks and partly to the desire to maintain people’s food cultures and food sovereignty.

This study deploys the food security pillars provided by the FAO (2012) to demonstrate that IK-based ways of food management are capable of addressing all the four food security dimensions, a critical observation toward revitalizing IK in managing growing food security challenges that are intensified by climate change in SSA.