Transformation of industrial food wastes into polyhydroxyalkanoates

Due to the synthetic and biologically inert nature of petroleum-derived plastics, the disposal of these solid wastes has been a focus of concern for waste management. Thus, the demand for biodegradable plastics has become a highly visible issue. Broader usage of biodegradable plastics in packaging and disposable products as a solution to environmental problems would heavily depend on further reduction in costs and the discovery of novel biodegradable plastics with improved properties. As the first step in pursuit of eventual usage of industrial food wastewater as nutrients for microorganisms to synthesize environmental-friendly bioplastics, the usage of soya wastes and malt wastes from a beer brewery plant were investigated as the carbon sources for the production of bioplastics. Bench experiments showed that microorganisms from the municipal activated sludges used the nutrients from malt and soya wastes to biosynthesise PHAs. The results of experiments indicated that with the proper selection of the type of food wastes as the carbon source, bioplastics with specific PHAs copolymers could be produced with distinct polymer physical properties.