Human milk oligosaccharides (HMO) have attracted great interest in recent years due to their role in boosting infants and adults health. According to several in vitro, in vivo and clinical studies, gastrointestinal and immune physiological systems benefit the most from HMO intake. Other organ systems, such as the respiratory, central nervous, circulatory, locomotor, and urinary systems have also been found to be affected by the HMO consumption in the recent decade. Due to their positive impact on human health, the incorporation of HMO into the infant formula or other functional foods has become highly desirable. Currently, their large-scale production is limited to 2’-fucosyllactose (2’FL) and lacto-N-neotetraose (LNnT) that are obtained through fermentation and added to the infant formula as fortifiers. Fewer advances have been made for other HMO to reach the industrial scale synthesis. The present paper summarizes the latest research on HMO in terms of their health benefits and synthetic methodologies, with the overall aim to establish the current status and trends in both fields.

Fucosyl-oligosaccharides are natural prebiotics that promote the growth of probiotics in human gut and stimulate the innate immune system. In this work, the release of α-lfucosidase by Lactobacillus rhamnosus GG, and the use of this enzyme for the synthesis of fucosyl-oligosaccharides were investigated. Since α-lfucosidase is a membrane-bound enzyme, its release from the cells was induced by addition of 4-nitrophenyl-α-l-fucopyranoside (pNP-Fuc). Enzyme activity associated with the cell was recovered at 78% of its total activity. Fucosyl-oligosaccharides where synthesized using α-l-fucosidase extract and pNP-Fuc as donor substrate, and D-lactose or D-lactulose as acceptor substrates, reaching a yield up to 25%. Fucosyllactose was obtained as a reaction product with D-lactose, and its composition was confirmed by mass spectrometry (MALDI-TOF MS). It is possible that the fucosyl-oligosaccharide synthesized in this study has biological functions similar to human milk oligosaccharides.