Nurturing with science: Alternative solution for human milk oligosaccharides through bioproduction techniques and their emerging applications in infant nutrition

Human Milk Oligosaccharides (HMOs) are bioactive carbohydrates found in human milk that play a crucial role in infant growth and health. However, due to several factors, such as maternal health conditions, lactation insufficiency, and socio-economic barriers, breastfeeding is not always feasible. This has led to the need for the synthesis of alternative HMOs to bridge the nutritional gap for non-breastfed infants. First, this review explains various physiological roles of HMOs in the overall growth and development of infants, followed by extraction of alternative oligosaccharides from multiple natural sources, including the milk of animals such as cows, goats, and camels, as well as from plant and marine sources. However, this method is limited by low yield, high purification cost, and significant compositional variability. Thus, advanced biotechnological processes for industrial-level production, such as microbial fermentation and enzymatic and chemical synthesis, including purification and characterization techniques, are discussed in this review. This review also evaluates each production method, emphasizing the industrial feasibility, scalability, and cost-effectiveness. The advantages and challenges of each large-scale production method are analyzed, followed by a discussion of emerging advancements in biotechnology and methodologies for improved HMO production. The review also highlights the clinical trials conducted in infants to assess the safety and efficiency of synthesized HMOs, as well as about the regulatory approvals that govern their addition in infant formulas and other supplementary products. Finally, various potential applications of alternative HMOs, like infant nutrition, pharmaceuticals, functional food, and emerging applications, are highlighted.