EVALUATION OF THE ANTIBACTERIAL PROPERTIES OF CITRUS AND POMEGRANATE PEEL EXTRACTS AGAINST BACTERIA CAUSING DERMATITIS

Abstract

Dermatitis is an inflammatory skin disease that is quite common and is often linked to bacteria like Staphylococcus aureus and Escherichia coli. With the rise of antimicrobial resistance, there is a demand for novel and alternative effective, safe and low-cost antibacterial agents. Fruit peels especially lemon (Citrus limon), orange (Citrus sinensis) and pomegranate (Punica granatum) are enriched with bioactive phytochemicals that have been reported to have antimicrobial properties. The main objective of the present study, therefore, was to assess the antibacterial activity of ethanolic, methanolic and n-hexane extracts of these fruit peels against the clinical isolates of E. coli and S. aureus collected from dermatitis patients. The peels of the fresh fruit were washed, dried, powdered and extracted individually with ethanol, methanol and n-hexane. Actively cultured clinical E. coli and S. aureus were isolated from the dermatitis-related wounds and identified by conventional microbiological methods. The Mueller-Hinton agar (MHA) was prepared and bacterial suspensions were standardized prior to inoculation. The antibacterial activity of the peel extracts was assessed by agar well diffusion method. The Dimethyl Sulfoxide (DMSO) were used as negative controls and Ciprofloxacin (5 µg) was used as positive controls. After 24 hours incubation at 37°C the diameter of the zones of inhibition was measured in mm. The results showed that the antibacterial activity of the peel extracts varied depending on the fruit types and extraction solvents. Ethanolic extracts had the highest antibacterial activity followed by methanolic extracts and n-hexane extracts had less antibacterial activity or none at all. The ethanolic extract of lemon peel was found to have the highest antibacterial activity against both the pathogens Escherichia coli and Staphylococcus aureus among all the tested samples. The antibacterial activity of pomegranate peel extracts was also found to be significant and orange peel extracts had moderate activity. The negative controls did not have any antibacterial activity and the positive control yielded the largest zone of inhibition. Based on the results of this study, it can be concluded that lemon, orange and pomegranate peel extracts have antibacterial activity against the bacterial pathogens associated with dermatitis and that ethanolic extracts are the most effective extracts. The findings indicate that fruit peel waste has the potential to be a good source of natural antibacterial agents that can be used economically and is environment friendly. Based on this, more extensive phytochemical characterizations, toxicity studies and in vivo studies are recommended to validate their therapeutic potential and future use in pharmaceutical applications.