GC-MS Profile and Antibacterial Evaluation of the Ethanolic Extracts of Banana and Sweet Potato Peels

Banana (Musa spp.) and sweet potato (Ipomoea batatas) peels are often discarded during food processing, yet they contain a wealth of bioactive compounds with promising health and industrial benefits. This study set out to explore the chemical composition and biological potential of these underutilized byproducts. The peels were first subjected to ethanol extraction using a Soxhlet apparatus. To better understand the chemical profiles of the extracts, Gas Chromatography–Mass Spectrometry (GC-MS) and Fourier Transform Infrared Spectroscopy (FTIR) were employed. The GC-MS analysis showed that banana peel extract was particularly rich in cis-oleic acid (24.85%) and resorcinol (19.02%), while sweet potato peel extract had a higher concentration of palmitic acid (39.66%) and pyrogallol (17.94%). FTIR spectroscopy supported these findings, revealing prominent O–H stretching bands around 3300–3400 cm⁻¹, C=O stretching peaks near 1700 cm⁻¹, and C–O vibrations between 1000–1300 cm⁻¹, all indicative of phenolic and fatty acid structures. Antioxidant assays revealed that banana peel extract exhibited stronger free radical scavenging activity, particularly at lower concentrations. On the other hand, sweet potato peel extract demonstrated notable antibacterial effects, especially against Pseudomonas aeruginosa. These findings therefore point to the untapped potential of banana and sweet potato peels as valuable resources for developing natural antioxidant and antibacterial agents. Their utilization not only adds value to agricultural waste but also supports sustainable and eco-friendly approaches in food, pharmaceutical and cosmetic industries.