Conversion of industrial food wastes by Alcaligenes latus into polyhydroxyalkanoates

Broader usage of biodegradable plastics in packaging and disposable product s as a solution to environmental problems would heavily depend on further r eduction of costs and the discovery of novel biodegradable plastics with im proved properties. As the first step in our pursuit of eventual usage of in dustrial food wastewater as nutrients for microorganisms to synthesise envi ronmental-friendly bioplastics, we investigated the usage of soya wastes fr om a soya milk dairy, and malt wastes from a beer brewery plant as the carb on sources for the production of polyhydroxyalkanoates (PHA) by selected st rain of microorganism. Bench experiments showed that Alcaligenes latus DSM 1124 used the nutrients from malt and soya wastes to biosynthesise PHAs. Th e final dried cell mass and specific polymer production of A. latus DSM 112 4 were 32 g/L and 70% polymer/cells (g/g), 18.42 g/L and 32.57% polymer/cel l (g/g), and 28 g/L and 36% polymer/cells (g/g), from malt waste, soya wast e, and from sucrose, respectively. These results suggest that many types of food wastes might be used as the carbon source for the production of PHA.