Evaluation of antibacterial activity of plant-food by-products and their potential application in livestock animals

To slow the pace of antibiotic resistance and preserve the efficacy of antibiotics for both human and veterinary medicine, there is a need to develop alternatives to antibiotics. This study aims to screen and evaluate the antibacterial activity of apple peel and potato peel powder on Escherichia coli and Staphylococcus aureus, providing alternatives to antibiotics to be used in livestock animals in the future.

In this study, bactericidal assay developed by Friedman et al (2002) was adopted with slight modifications to study the antibacterial activity of apple and potato peel samples. The results showed that 4 types of apple peel powder and 3 types of potato peel powder exhibited a low level of anti-E. coli activity at the concentration range from 0.03 mg/mL to 0.67 mg/mL; however, 7 types of potato peel powder showed a notable antibacterial activity on S. aureus when at or above the concentrations of 13.33 mg/mL (the resulting highest % Kill to S. aureus ranged from 68.9% to 99.3%) within three hours.