ABSTRACT
Sialyllactose is one of the important components of breast milk oligosaccharides. Sialyllactose consists of N-acetylneuraminic acid (NeuAc) and lactose as monomers, and the main forms of sialyllactose are 6′-sialyllactose (6′-SL) and 3′-sialyllactose (3′-SL). Sialyllactose is essential for infant brain development, and it also has the effects of resisting pathogens, enhancing immunity, and promoting the reproduction of intestinal probiotics. It has broad application prospects in the fields of functional food additives, and its demand will continue to increase in the future. This chapter introduces research on the synthesis of sialyllactose from three perspectives: chemical synthesis, enzymatic synthesis, and microbial synthesis. The research progress of protein engineering and metabolic engineering in whole-cell catalysis and de novo synthesis of sialyllactose are summarized and compared. In addition, this chapter discusses the strategies for efficient production of sialyllactose by microbial synthesis, such as the construction of basic recombinant strains, the modification of key enzymes in metabolic pathways, and the balance of cellular metabolic pathways through dynamic regulation. This chapter promotes understanding of developments in the field of sialyllactose synthesis and helps to further improve its production.
