Structural and functional investigations of wall material extracted from banana peels

Abstract

The core objective of the current study was to extract heteroxylans from banana peel. Firstly, banana peels were dried to make fine powder, and their nutritional profile including moisture, crude fat, crude ash, crude protein, crude fiber, and nitrogen-free extract (NFE) was noted. Secondly, the heteroxylans were extracted from banana peels, and their bioactive profile was assessed, including total phenols and flavonoids contents, and their activity was assessed through commonly used antioxidant assays including DPPH, FRAP, and ABTS+. Heteroxylans were extracted through alkali extraction method, and their structural characterization was assessed through XRD and FTIR. The results showed that moisture content in banana peels were 60.73 ± 0.85% and 15.77 ± 0.33% in air dried and grounded banana peels, respectively, crude fat 3.94 ± 0.10%, crude protein 6.06 ± 0.15%, and NFE 48.13 ± 0.32%. The total dietary fiber of banana peel powder was 45.3 ± 0.45%, insoluble dietary fiber 34.23 ± 0.30%, and soluble dietary fiber 15.63 ± 0.25%. The bioactive profile of heteroxylans content in banana peels include TPC (19.83 ± 1.10 mg GAE/g), TFC (22.73 ± 0.90 mg QE/g), DPPH (40.73 ± 0.80 mg TE/g), FRAP (39.63 ± 0.73 mg TE/g), and ABTS+ (83.43 ± 0.70 (mg TE/g). The yield of extracted heteroxylans was 9.95 ± 0.17 g/100 g. Further, the structural characterization through XRD showed the amorphous nature of banana peels heteroxylans, and FTIR showed the typical spectra in which different functional groups were observed. Conclusively, the current study showed that banana peels’ heteroxylans has unique nutritional, bioactive, and structural profile and can be utilized for various industrial purposes to enhance technological and nutritional properties using as food additive and way toward the sustainability.