Recombinant production of structured fats that mimic human milk fat

Abstract Human breast milk is the choice nutrition for infants, and the fat component of the milk (human milk fat, HMF) supplies the highest fraction of the infant's required dietary energy. The fats within human breast milk are triacylglycerols (TAGs) with a unique stereoisomeric structure that facilitates efficient nutrient absorption in the infant gut. In contrast, vegetable oils form the main source of fats in commercial infant formulas: the composition and distribution of the fatty acids in vegetable oils are different from those in human milk which hinders nutrient absorption in infants, and consequently their growth. To mimic the nutritional functions of human milk fat, human milk fat substitutes (HMFS) have been developed through enzymatic interesterification reactions in recent years. Human milk fat substitutes (HMFS) produced by in vitro enzyme-catalysis of purified vegetable oils, have the desired properties but are challenging to manufacture with high cost. Yali Bio aims to use its recombinant yeast platform to provide a biomanufacturing solution for high quality HMFS that is cost-effective. We propose to use our platform to efficiently produce structured fats that resemble human milk fat in their physicochemical properties and generate highly productive, proprietary yeast strains accumulating fats with a stereoisomeric composition similar to human milk fats. The approach described here should lead to a cost-effective biomanufacturing method for recombinant production of structured fats that mimic human milk fats.