Optimization of the Cultivation Conditions of Cupriavidus Necator for the Production of Polyhydroxyalkanoates from Cassava Peels Waste

The interest in the development of biopolymers is increasing due to the plastic waste management issues and the depletion of fossil fuels. Polyhydroxyalkanoates (PHAs) are a family of biodegradable and bio-based polymers with high potential for replacing the petroleum-based plastics. Nevertheless, their high production cost, mainly caused by the cost of the feedstock, hinders their commercialisation. The use of alternative feedstock sources such as biomass waste is proposed as a strategy to decrease the price of PHAs while helping to address the biomass waste management challenges. Cassava is an example of biomass with high potential to be transformed into PHAs due to its high content of sugars. Here we present an optimization strategy for the hydrolysis of cassava peels into reducing sugars and its further bioconversion into PHAs. Results show a reliable and significant mathematical model foe the hydrolysis, allowing highest conversion rates of 85% of cassava peels into reducing sugars. Microbial growth achieved was comparable to the use of defined media and promising PHAs production were obtained (20% gPHAs/gDCW).