Bioplastics and wax esters from wood through co-culture of bacteria and yeast

Research Project, 2020 – 2023

Lignocellulosic hydrolysate made from forest biomass has so far not been widely exploited in biotechnological production processes, mainly due to its toxicity for the production hosts. Furthermore, the lignin fraction of the hydrolysates cannot be used in yeast-based processes. We introduce new solutions for both these bottlenecks, material toxicity and inefficient carbon utilization, and develop new sustainable products and processes that facilitate resource efficiency and combating climate change. We propose a novel approach for valorisation of wood biomass to lactic acid and wax esters by consolidated bio-detoxification and fermentation. Our production process is based on two species, the yeast Saccharomyces cerevisiae and the bacterium Acinetobacter baylyi ADP1. ADP1 is capable of detoxifying the raw material, enabling the yeast to grow. ADP1 produces wax esters from the lignin-components of the hydrolysate. By engineering programmable autolysis of the yeast cells, also yeast biomass will be used for wax ester production in the final stage. The production process will be designed to support co-cultivation, forming a closed loop, where all carbon is converted to bioproducts. The consortium is supported by a collaboration with the chemical department at IIT Guwahati, India. This partner will purify and
polymerize the lactic acid produced, resulting in proto-type bioplastic materials, demonstrating the feasibility and applicability of the concept proposed.