The development of lignocellulosic biorefineries is the key to the sustainable bioethanol production. New technologies for the production of lignocellulolytic enzymes, protein engineering and the rational development of enzyme mixtures are of great importance in this area. In this context, the wood feeding insects, such as the termites, are biological systems considered as models for the study of plant biomass conversion with potential application in the biorefinery development. Preliminary results of our research group suggests that pro-oxidant, antioxidants and detoxifying enzymes (PADs) can be the advantage of termites which makes them one of the most efficient biological systems in the conversion of lignocellulose. Continuing the researches from the master degree, an aldoketo reductase from the termite Coptotermes gestroi (CgAKR-1) had proven its role in the insect digestomics. This enzyme was able to increase the efficiency of commercial cellulolytic cocktails in the hydrolysis of sugarcane bagasse. The enzymes also acted as a detoxication agent in the hemicellulose hydrolyzate from sugarcane bagasse. The detoxified hydrolizate was better fermented by xilose fermenting yeast after the enzymes treatment. In other words, the enzyme was proved to be a potential integrative enzyme in this chain. However, our studies revealed that the enzyme has no optimal thermal stability for industrial processes of sugar cane bagasse hydrolysis. Thus, the objectives of this PhD project focuses on the biotechnological applicability of an aldoketo reductase found in the termite Coptotermes gestroi (CgAKR-1). In order to achieve this goal we intend then: 1- improve the robustness of the enzyme against temperature compatible with the enzymatic hydrolysis of sugarcane bagasse; 2- heterologous production of CgAKR-1 in Aspergillus; 3- Develop saccharification process of sugarcane bagasse with cellulolytic cocktails supplemented with CgAKR-1; 4 Apply CgAKR-1 in the detoxification of fermentation inhibitors present in hemicellulose hydrolyzate, to increase efficiency in the fermentation of this source of pentoses.
News published in Agência FAPESP Newsletter about the scholarship: