Biotechnological production of 2-keto-D-gluconic acid (2-KGA): from strain engineering to process development

The global inclination in the production of building block chemicals is shifting in the direction of sourcing sustainable resources and implementing circular economy frameworks. Biotechnological approaches facilitate the economic advancement of precursor production through the valorization of waste biomass while alleviating the impacts on ecology. Strategies in white biotechnology enable the utilization of affordable and renewable resources for the synthesis of a wide spectrum of bio-based compounds. Considering the increasing market demand for 2-keto-D-gluconic acid and its derivatives, this review provides a systematic overview of its physicochemical properties and applications across different industries. This paper critically compares chemical and microbial production methods, with a particular focus on the microorganisms employed, the substrates utilized and the mode of operation. Notably, this review covers emerging trends in the utilization of agro-industrial residues as substrates and highlights advances in microbial strain engineering and process optimization. In addition to providing a comprehensive overview of the critical aspects of 2-KGA production, this article underscores the key challenges and outlines necessary advancements. This study intends to steer future research toward optimizing 2-KGA production processes for more environmentally sustainable methods.