Performance of Recombinant Komagataella phaffii in Plant-Based Meat Flavor Compound-Leghemoglobin (LegH) Production through Fed-Batch Fermentations

Abstract

Soy leghemoglobin (LegH) has been gaining interest over the last years as an efficient flavor and aroma compound in plant-based meat substitutes. Hence, in the following article, we demonstrate the methods for LegH production using a recombinant Komagataella phaffii strain. Multiple fed-batch fermentation with an alternative to a BSM medium, where glucose was used as the main carbon source, was implemented and the growth kinetics, e.g., a maximal specific biomass growth of 0.239 g·g−1·h−1, a biomass yield from the substrate of 0.298 g·g−1, and a maximal specific substrate consumption rate of 0.81 g·g−1·h−1 were identified. Leghemoglobin production resulted in a yield of 0.513 mg·gDCW−1, while the highest biomass density achieved in this study was 121.80 gDCW·L−1. The applied medium that showed potential for additional optimization studies, which, in contrast to BSM, made it possible to separate pH control from nitrogen supply, does not affect medium turbidity measurements and does not induce metabolite synthesis during yeast biomass growth.