Abstract

The aim of this study was to evaluate the bacteriological load in Moringa oleifera Lam. leaves consumed in Guinea Savannah vegetation zones of Nigeria, via: Abuja (Gwagwalada market), Southern Guinea Savannah; Katsina (Daura market), Northern Guinea Savannah and Sokoto (Central market), Sudan Guinea Savannah. Three fresh and dried M. oleifera Lam. leafy samples each of 50 g were randomly collected per market location for analysis of total viable cells (cfu/mL) using standard procedures of analyses. The bacterial load in each sample was determined in triplicates and analyzed with SPSS Version 16. Bacterial isolates were classified on the basis of cultural morphology, Gram reaction and biochemical tests. Results showed bacterial growth on Nutrient, Mannitol and MacConkey media. Sabouraud dextrose, Brilliant green and Salmonella-Shigella media recorded no growth in all the leave extracts analyzed. This could be ascribed to the selective nature of the Sabouraud dextrose, Brilliant green and Salmonella-Shigella media, and suggested that fungi/yeast, Salmonella spp. and Salmonella-Shigella species were not among the bacterial contaminants or that the active ingredient component-Pterygospermin, in M. oleifera leaves extract inhibited the growth of micro-organisms in the leaves extract. The study recorded two pathogenic bacteria from all the locations, with S. aureus being more dominating, followed by Escherichia coli and these organisms suggest health hazards. Consumers and vegetable vendors should be educated on proper hygienic handling, transportation and storage of vegetables to avoid bacteriological food spoilage and other related health issues.

Key words: Moringa oleifera leaves, nutritional quality, bacteriological load, vegetables.