Background: Food safety problems still persist across the globe and remain a challenge to the general public and government. The study determined the microbiological quality of pre-cut vegetable salads sold in the Central Business District (CBD) of Tamale. Results: A total of thirty (30) salad samples were purchased from four zones of the District and transported to the Spanish Laboratory of the University for Development Studies, Ghana for analysis. Standard microbiological methods that are in accordance with American Public Health Association (APHA) were used in determining the presence and levels of bacteria in the salad samples. Escherichia coli were detected in 96.7% of salad samples with levels ranging from 0 to 7.56 log10 cfu/g. Bacillus cereus were present in 93.3% of ready-to-eat vegetable salads with counts ranging from 0 to 7.44 log10 cfu/g. Further, Salmonella spp. and Shigella spp. were present in 73.3% and 76.7% of salads, respectively. Salmonella spp. and Shigella spp. counts ranged from 0 to 4.54 log10 cfu/g and 0 to 5.54 log10 cfu/g, respectively. Statistically, Escherichia coli, Bacillus cereus and Shigella spp. Contamination varied significantly (p < 0.05) across the four zones demarcated. However, Salmonella spp. contamination did not vary significantly (p > 0.05) across the zones.

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Biofloc technology (BFT) systems have been driven towards increased sustainability in the last decade. BFT depends on maintenance of the optimal carbon-to-nitrogen (C/N) ratio through supplementation with organic carbon sources. The types of carbon sources and addition strategies are critical considerations in BFT systems. Thus for the purpose of this review, a thorough search of the literature was conducted to gather relevant information from reliable sources, ranging from reputable journals to books and useful reports in the field of BFT. Keywords used for the literature search include: 'biofloc technology systems', 'carbon sources', 'solid carbon sources', 'effects of carbons sources', 'carbon source addition strategies', 'nutritional quality of bioflocs', 'carbon sources and water quality', 'C/N ratio in BFT', and 'carbon sources and bacterial community'. Among the several peer-reviewed articles, books and technical reports consulted, 147 (dated from 1987 to 2020) were relevant for the preparation of this review. The current review thus examines the subject of supplemental carbon sources in BFT systems and discusses the various effects of their application with respect to the culture organism, microorganisms, water quality and the nutritional quality of flocs. The benefits and challenges associated with the types of carbon sources used in BFTs are also presented. Suggested organic carbon sources and their addition strategies are provided, and further research directions are proposed.

The abundance of nitrogen compounds, phosphorous compounds and organic matter in biofloc technology (BFT) aquaculture systems creates an ideal medium for increasing microbial communities and load. The abundance of microbial DNA found in BFT aquaculture systems is hypothesised to be among the greatest in current aquaculture systems. Several factors mediate the bacterial diversity, relative abundance and dynamics in BFT systems. This review focusses on the bacteria in BFT aquaculture systems, their role as food for animals present in the culture and their various relationships with major nutrients. The analytical techniques available for determining bacterial integrity and function are reviewed along with the factors that affect microbial community structure, water quality and production performance. Future investigations to characterise bacteria in BFT aquaculture systems and their roles and mediating factors are suggested.