ANTIMICROBIAL ACTIVITY OF OCIMUM GRATISSIMUM, ALCHORNEA CORDIFOLIA AND NAUCLEA LATIFOLIA LEAVES EXTRACT AGAINST BACTERIA STRAINS CAUSING FOOD POISONING

Prevention of food spoilage and food poisoning pathogens is usually achieved by the use of chemical preservatives which have negative impacts including: human health hazards of the chemical applications, chemical residues in food and feed chains and acquisition of microbial resistance to the used chemicals. Because of such concerns, the necessity to find a potentially effective, healthy safer and natural alternative preservatives is increased. Within these texts, plant extracts have been used to control food poisoning diseases and preserve foodstuff. Antimicrobial activity of three plant extracts (Ocimum gratissimum, Alchornea cordifolia and Nauclea latifolia) were investigated against Staphylococcus aureus, Streptococcus spp, Escherichia coli and Micrococcus spp using agar disc diffusion technique. Zones of clearance on Streptococcus spp by all three plants range from 5mm-20mm, with Alchornea cordifolia aqueous and methanolic extract having 18mm and 20mm zones of clearance respectively. The lowest zones of clearance was recorded in Nauclea latifolia methanolic extract (5mm). The highest zone of clearance against Staphylococcus aureus was recorded in Alchornea cordifolia aqueous (20mm) and methanolic extract (22mm) respectively while the lowest zones of inhibition was recorded in Nauclea latifolia methanolic extract (4mm). Alchornea cordifolia aqueous and methanolic extract have the highest zones of clearance against all tested organisms. These plant extracts which proved to be potentially effective can be used as natural alternative preventives to control food poisoning diseases and preserve food stuff avoiding healthy hazards of chemically antimicrobial agent applications.