Research seminar: December 1, 2023

How to Best Preserve Human Donor Milk’s Bioactive Proteins

December 1, 2023

This presentation will discuss how human milk contains bioactive proteins that improve health outcomes in infants, noting that premature infants are often fed donor human milk due to insufficient parental supply.

To ensure safety, donor milk is processed with heat to kill bacteria. However, heat-based pasteurization methods degrade some key bioactive milk proteins, decreasing milk's benefits for these infants.

Members in the Dallas Lab are investigating how novel donor milk processing methods (high pressure processing and ultraviolet-C irradiation) can enhance donor milk safety while better preserving milk protein structures and functions to help improve infant health.

Speaker

Dave Dallas, PhD
Associate Professor of Nutrition
College of Health, Oregon State University

The overall aim of Dave's research is to identify novel, evolutionarily relevant bioactive compounds in human and bovine milk and the extent to which they survive throughout the digestive system.

In particular, he is interested in bioactive milk proteins and fragments of proteins—peptides—released within the mammary gland and during digestion.

Milk peptides have an array of known functions, including antimicrobial and immunomodulatory actions that are relevant to infant health.

We are examining the peptides present in milk and those released during digestion via mass spectrometry-based peptidomics and in vitro functional assays.

He's also particularly interested in improving health outcomes for preterm infants. His work demonstrates that preterm infants have lower ability to digest milk protein compared with term infants. He is now examining whether digestive differences lead to different bioactive peptide release in the gut of preterm and term infants.

Difference in digestive capacity may mean that premature infants are not receiving the full health benefits of milk.

Beyond peptides, his lab also examines the digestion of milk proteins, particularly immunoglobulins (antibodies) using proteomics, ELISA and functional assays. Moreover, his lab has developed techniques to detect glycoproteins and glycopeptides across digestion.

In addition to his work with infants, he is examining the digestion of dairy proteins in adults. His lab is currently examining digestion of glycomacropeptide (a peptide in whey protein) and the extent to which it retains its immunomodulatory and antibacterial actions in the gastrointestinal tract.