[Biosynthesis and functions of human milk oligosaccharides]

Human milk oligosaccharides are unique functional oligosaccharides found in human milk. They possess various biological activities such as health-benefiting, immunomodulatory, antiviral, and antitumor activities, thus playing an important role in maintaining health. Due to the high difficulty of chemical synthesis and the low yield from natural extraction, the scaled-up production of human milk oligosaccharides has become a hot research topic of both synthetic biology and food science. In this article, we summarize the physiological functions and application potential of human milk oligosaccharides, with a focus on their biosynthetic technologies. On the basis of metabolic engineering, different chassis cells such as Escherichia coli are selected to significantly increase the yield of human milk oligosaccharides via synthetic biology techniques. The biosynthesis and promotion of human milk oligosaccharides will present new challenges and opportunities for the development of new products in the food and pharmaceutical industries.