Effects of heat treatment and simulated digestion on the properties and osteogenic activity of bovine lactoferrin.

Lactoferrin (LF) is known to stimulate osteoblast proliferation and differentiation, potential to be applied in products improving skeletal health. However, LF is sensitive to thermal processing, and oral administration leads to hydrolysis in gastrointestinal tract, probably influencing the osteogenic activity. To determine the impacts of heat treatment, we explored the changes in secondary structure and surface hydrophobicity underlying aggregation along with surface charge alteration of bovine LF under four conditions commonly used in dairy production and found 72 °C/15 s, bringing the least structural alteration, was optimal to retain effect of LF promoting osteogenesis, while LF was completely deprived of the effect treated at 85 °C/10 min and 95 °C/10 min. In vitro adult and infant digestion models were established to identify the degradation of LF, and, despite impaired effect on osteoblast growth, LF hydrolysates from intestinal digestion stage presented stronger effect of boosting osteoblast differentiation independent of p38 and vitamin D receptor. [Display omitted] • 72 °C/15 s is optimal to retain structure and osteogenic activity of lactoferrin. • 85 °C/10 min and 95 °C/10 min severely impair osteogenic activity of lactoferrin. • Lactoferrin loses effect of promoting osteoblast proliferation with degradation. • Gastrointestinal digests of lactoferrin stimulate osteoblast differentiation. [ABSTRACT FROM AUTHOR]