STM Article Repository

Aims: Different selling points or markets in Ilara-Mokin town were visited after the market session and a day after to collect vegetable wastes. This research aimed to isolate bacteria and fungi from selected waste vegetables, to infect laboratory animals with the bacterial isolates and to study the effect of the isolated bacteria on the laboratory animals.

Methodology: Three major vegetable wastes were commonly found in the markets and they are Amaranthus cruentus (Arowojeja), Senecio biafrae (Worowo) and Spinacia oleracea (Amunututu). Sufficient quantity of these decaying wastes were collected and sterile crucible was used to grind the waste samples. On each sample, serial dilution was done using 2g. Nutrient Agar and potato dextrose agar were used for isolation of bacteria and fungi respectively. Standard Microbiological methods were used for the identification of the microorganisms.

Results: Five bacteria were isolated from the waste, which are: Salmonella spp, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Proteus mirabilis. Also six fungi were isolated from the waste vegetable. They are: Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Penicillium chrysogenum, Geotrichum spp. and Articularia quercina. All of the bacteria were sensitive to commercial antibiotics like ciprofloxacin and gentamicin, except Salmonella spp that showed resistance to Tetracycline, Augmentin and Ceftriaxone. The bacterial isolates were then used to infect Albino rats and haematogical analysis was performed on the animals’ blood. The result showed that Proteus, and Pseudomonas reduced the PCV from 45.55±1.67% (in control group) to 36.75±0.55% and 37.25±0.33% respectively. The haemoglobin concentration was decreased from 15.00±0.00 (in control group) to 12.33±0.67 in the group infected with Pseudomonas. The white blood cell count was highest on the group infected with Salmonella with a count of 12.2±0.96×105 mm-3. Histopathological Analysis of the liver and intestine of the rats showed that the pathogenic microorganisms cause negative pathological effects such as absence of sinusoid in the liver hepatocytes, hepatocellular drainage and necrosis, while only necrosis and haemorrhage were prominent in their intestine.

Conclusion: The result obtained has shown that pathogenic microorganisms from these vegetable wastes can cause serious health problem for the public if not disposed adequately, especially when these vegetable vendors place freshly harvested ones on the same ground the next market day; and when such is bought and not properly washed or cooked.