Improvement of physcio-chemical and functional properties of alginate film by Acacia lignin

Abstract

Abstract The present work focuses on the development of novel Acacia lignin-alginate (LA) based biodegradable film as packaging material. Results revealed that the Acacia lignin has good potential to be blended into alginate film to synthesize active antimicrobial, antioxidant biodegradable film. The study was performed to develop LA based films in the presence of glycerol as plasticizer. Lignin extracted from Acacia wood by alkali method was used for the preparation of LA blended films using solution casting method with varying ratio of lignin. The physico-chemical properties, in-vitro cytotoxicity, antimicrobial activity and drug release behavior of the film were investigated. Alginate films incorporated with lignin had significantly lower water solubility (up to 26%) and tensile strength (TS, 0.146 MPa). Infrared spectroscopy suggested that lignin interacts with alginate by hydrogen bonding. Mechanical and thermal properties of films vary as a function of lignin content, showing optimum values for films modified with 20% (w/v) lignin. The LA blended film had improved light barrier and antimicrobial properties with low cytotoxicity, which is useful in food applications for preventing ultraviolet-induced lipid oxidation. Hence, the use of LA film could be a useful for maintaining the quality and shelf life of food and non-food product.