Physico-chemical, biological properties of chitosan/gelatin-based films with Finger Millet bran extract

The chitosan/gelatin-based films were prepared by incorporation of Finger millet bran extract (FMBE) with different concentrations and their physico-chemical, antioxidant and antimicrobial activities were investigated. The results indicated the thickness was gradually increased, whereas the water content, water absorption light and transmittance at 600 nm was significantly decreased with the addition amount of FMBE. The water vapor permeability of films was significantly decreased after incorporation of 0.25 and 0.5% of FMBE, whereas it was significantly increased after incorporation of 0.75 and 1.00% of FMBE. Loading with FMBE significantly enhanced the antioxidant activity, antibacterial activity against Escherichia coli and antifungal activity against Penicillium nettle. The FTIR revealed that strong interactions between FMBE and chitosan/gelatin matrix when 0.25 and 0.5% of FMBE were added into the films. Scanning electron microscopy analysis revealed that FMBE could incorporate into the chitosan/gelatin matrix well at an appropriate concentration that resulted in smooth and uniform surface. In summary, the addition of FMBE at an appropriate concentration (≤ 0.5%) could improve the physico-chemical properties, biological activities of the chitosan/gelatin films.