Antimicrobial and antioxidant potential of banana (Musa sapientum) peel extracts of variety grand naine, major compound 5-hydroxymethylfurfural in methanolic peel extract and its derivatives

Banana peel extracts were prepared by using various solvents. Gas Chromatography-Mass Spectrometry analysis of methanolic extract showed 5-Hydroxymethylfurfural (24.78%) as major compound which was isolated from extract and chemically transformed into two derivatives viz. [5-(3-Nitrophenyliminomethyl)furan-2-yl] methanol (2) and 5-Hydroxymethylfurfurali deneacetophenone (3). The peel extracts, 5-HMF and its derivatives were tested for their antibacterial potential against Klebsiella pneumoniae and Pseudomonas aeruginosa, antifungal potential against Fusarium oxysporum and antioxidant potential. Maximum antibacterial potential was exhibited by methanol extract with minimum inhibitory concentration (MIC) at 30 and 45 pg/ml against Klebsiella pneumoniae and Pseudomonas aeruginosa, respectively. Ethyl acetate extract possessed maximum antifungal potential with MIC value at 300 pg/ml. 5-Hydroxymethylfurfurali deneacetophenone exhibited maximum antioxidant potential with median inhibitory concentration (IC₅₀) value of 25.50 and 30.00 pg/ml against DPPH and NO radical scavenging assays, respectively. Hence, banana peels can be used to form biologically active compounds as safe and biodegradable antimicrobial and antioxidants.