Fabrication of snapper fish scales protein hydrolysate-calcium complex and the promotion in calcium cellular uptake

It has become a hot topic to find natural food substances which can effectively promote calcium absorption in human body. Given this, protein hydrolysate with calcium-binding capacity was prepared from fish scales (FSPH) and its promotion in calcium cellular uptake was investigated in this study. The binding of calcium to the amino nitrogen atoms and the carbonyl oxygen atoms of FSPH led to the structural folding and aggregation. The calcium cellular uptake efficiency in Caco-2 cells population model was significantly increased in the form of FSPH-calcium complex. Furthermore, FSPH-Ca could effectively resist the inhibitory effect of dietary inhibitors on calcium cellular uptake. The mRNA expression of transient receptor potential vanilloid 6 (TRPV6) in Caco-2 cells was remarkably elevated with FSPH-Ca treatment. The results improved the understanding of the interaction mode of protein hydrolysate and calcium, and provided a basis for developing FSPH-Ca as functional foods to improve calcium absorption.