Investigation of Bactericidal effect of Earwax on Escherichia coli and Staphylococcus aureus isolated from skin and stool samples of undergraduate students, Federal University of Agriculture Makurdi, Benue State, Nigeria

Earwax is a normal product of the ear, which protects the skin of the ear from water, dirt dust and infection. The aim of this study was to determine the antibacterial activity of earwax on Staphylococcus aureus and Escherichia coli isolated from skin and stool respectively. Bacteriological investigations were carried out using culture and morphological characteristics, conventional biochemical tests and antibiotic susceptibility testing of both earwax and conventional antibiotics against the presumptive isolates. Occurrence of Staphylococcus aureus (58.3%) and Escherichia coli (45.8%) in skin and stool samples were respectively determined based on cultural and morphological characteristics. Conventional biochemical tests were carried out on the 14 and 10 presumptive Staphylococcus aureus and Escherichia coli isolates and then 10 and 8 presumptive isolates were detected respectively. The antibacterial activity of the test agent was determined using the agar well diffusion technique; five different concentrations (20% v/v, 40% v/v, 60% v/v, 80% v/v, and 100% v/v) of the test agents were evaluated against the bacterial isolates. The earwax showed antibacterial activity against both isolates (except the 20% v/v for Staphylococcus aureus) at all concentrations used with antibacterial activity directly proportional to earwax concentration and a better antibacterial activity against Staphylococcus aureus (zone of inhibition 20mm) aureus than Escherichia coli. Antibiotic susceptibility testing was carried out on the 10(41.7%) and 8(33.3%) presumptive isolates of Staphylococcus aureus and Escherichia coli respectively based on Kirby Bauer method. Highest rate of susceptibilities of the Staphylococcus aureus isolates to antibiotics were observed in Erythromycin (100%), while for Escherichia coli were observed in Erythromycin and Levofloxacin (100%). Meanwhile, highest rate of resistant to Staphylococcus aureus isolates were observed in Gentamicin (100%) while for Escherichia coli was observed in Amoxicillin (100%). This study shows that earwax plays a critical role in the fight against infectious microorganisms as some of the antibiotics.