Antioxidant, antibacterial and antifungal activity of edible coating chitosan-galactose complex

Abstract

The purpose of this research was to observe the antioxidant, antibacterial and antifungal activity of an edible coating chitosan galactose complex. The treatments were: A Control chitosan; B Control commercial chitosan; C Chitosan with 0.5 g Galactose; D Chitosan with 1 g Galactose; and E Chitosan with 1.5 g Galactose. The coatings were evaluated using in-vitro testing. The parameters analysed were antioxidant activity (DPPH method), antibacterial and anti fungal activity (inhibition zone method). The result showed that the 1 g galactose-chitosan complex performed better as an antioxidant than chitosan. Antioxidant analysis with the DPPH method found IC50 values of 43.20 - 73.15 ppm, with chitosan galactose complex (D) as the best antioxidant among the tested treatments. Antibacterial activity of the chitosan galactose complex (D) against pathogen bacteria from tilapia fillets produced a 12 mm inhibition zone. Antifungal activity of the chitosan galactose complex (D) against pathogenic fungi from smoked fish produced an 18 mm inhibition zone. This chitosan galactose complex could be used as a natural food preservative.