American Research Journal of Food and Nutrition

Probiotics have been defined a number of times. Presently, the most common definition is that from the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) (2012) which states that probiotics are live microorganisms that when administered in adequate amounts, confer a health benefit on the host. Probiotic bacteria are found in the human gut where they provide health benefits to the host. They do so by producing nutrients and cofactors, successfully competing with pathogens and stimulating host immune responses by producing specific polysaccharides. These bacteria can also alleviate the symptoms of disease-related disorders. This study was carried out on the health benefits derived from the use of probiotics. Food such as the fermented African Nightshade and two different fermented juices were analyzed in the laboratory so as to determine the different types of probiotics that are found in them and also their interaction with pathogenic bacteria (Escherichia coli and Staphylococcus aureus). These pathogenic bacteria were cultured with the probiotic bacteria in order to determine their interaction. Microorganisms derived from the fermented vegetables were cultured in nutrient agar media. For the fruit juices, serial dilution was done, subjected to culture in an incubator for 24 hours and later identification of the bacteria by their morphological characteristics, biochemical tests, Gram staining technique and also by Bergey’s Manual of determinative bacteriology. The probiotics that were present in the fermented juices included Pediococcus spp, Enterococcus spp, Bacillus spp, Bifidobacterium spp, Lactobacillus spp and Streptococcus spp. While bacteria present in fermented African Nightshade (Solanum villosum) include Leuconostoc spp and Lactobacillus spp. These bacteria inhibit the growth of pathogenic bacteria by forming zones of inhibition. Therefore, the fermented juices and fermented African Nightshade (Solanum villosum) have probiotic bacteria that inhibit the growth of pathogenic bac