Enzymatic degradation of microbial poly(3‐hydroxybutyrate) films

Abstract

Abstract The effects of crystallinity and spherulite size on the enzymatic degradation of microbial poly(3‐hydroxybutyrate) (PHB) films have been studied at 37°C and pH 7,4 in aqueous solutions of an extracellular PHB depolymerase from Alcaligenes faecalis T1. The rate of enzymatic degradation of PHB films decreases with an increase in crystallinity, but it is little influenced by the size of PHB spherulites. It was suggested that the PHB depolymerase firstly hydrolyzes the PHB chains in the amorphous state on the surface of the films and subsequently erodes the PHB chains in the crystalline state.