Antimicrobial effects of edible nano-composite based on bean pod shell gum, nano-TiO2, and mentha pulegium essential oil

Abstract

Natural antioxidants in edible coatings can modify the structure and improves the functionality and applicability of the film in food industries. This study was done to determine the antimicrobial effect of nano-composite based on bean pod shell gum (4% w/v), TiO2 nano-particles (NPs) (1%–2% w/v) and Mentha pulegium essential oil (EO) (2%–4% v/v) on five food-borne pathogens in two categories, including Gram positives and three Gram-negatives bacteria. The antimicrobial activity was tested using disk diffusion test. According to the results, Gram-positive bacteria were more susceptible than Gram-negative bacteria. Increasing M. pulegium EO and TiO2 NPs content increased the antimicrobial activity of the edible film based on bean pod shell gum, so that the treatment containing 4% v/v M. pulegium EO and 2% w/v TiO2 NPs led to the highest inhibition zone (11.8–15.2 mm) compared to treatment containing 2% v/v M. pulegium EO and 1% w/v TiO2 NPs with inhibition zone range of 9.8–11.5 mm. In general, TiO2 NPs and M. pulegium EO improved the functional properties, including antimicrobial activity of the edible film based on bean pod shell gum which increases the potential of films to be used for fresh products.