Calcium supplements and structure–activity relationship of peptide-calcium chelates: a review

Casein phosphopeptide calcium chelation: preparation optimization, in vitro gastrointestinal simulated digestion, and peptide fragment exploration

“…The CPP-Ca, calcium gluconate, and calcium L-aspartate, after gastric digestion, were dissociated in an acidic environment but re-chelated in the intestinal tract because the weak alkaline environment of the intestinal tract makes calcium ions more easily re-conjugate with peptides. These results were consistent with a previous study performed by Zhang et al 5 Furthermore, with the increase in digestion time, compared with other calcium preparations, CPP-Ca always had the highest proportion of chelated calcium, indicating that it could protect calcium under alkaline conditions and prolong the absorption time of calcium. Obvious precipitation was also observed for calcium gluconate and calcium L-aspartate, whereas no obvious precipitation was observed for calcium casein phosphopeptide (Fig.…”

“…All other reagents and chemicals used were analytical grade from commercial suppliers Preparation of CPP-Ca Casein phosphopeptide was dissolved in deionized water to prepare solutions of different peptide concentrations (1-11 g kg −1 ), and then CaCl 2 was added in different mass ratios (2:1-22:1). The mixtures were incubated for 40 min in a water bath at different temperatures (10-60 °C) and pH (5)(6)(7)(8)(9)(10)(11). After adding two to three drops of calcium indicator to the reaction solution, a 0.015 M Ethylene Diamine Tetraacetic Acid (EDTA) solution was added slowly from a burette until the color changed from purple to blue, and the EDTA consumption was recorded as the volume of total calcium.…”

“…Furthermore, the most significant disadvantage of organic calcium is its low calcium content. Peptide‐chelated calcium has therefore attracted much attention as an excellent calcium supplement 4,5 …”

“…Peptide-chelated calcium has therefore attracted much attention as an excellent calcium supplement. 4,5 Casein phosphopeptide (CPP) is a biologically active peptide derived from cow's milk with a highly acidified active center (-SerP-SerP-SerP-Glu-Glu-) in the amino acid sequence. 6,7 It has important physiological functions such as promoting the absorption and utilization of mineral elements, 8,9 preventing dental caries, 10 antioxidation, 11 and enhancing immunity.…”

Structural characterization and calcium absorption‐promoting effect of sucrose‐calcium chelate in Caco‐2 monolayer cells and mice

“…These include inorganic calcium (such as CaCO 3 and CaCl 2 ), organic calcium (such as calcium gluconate and calcium lactate), and amino acid calcium (such as calcium glycinate and calcium aspartate) (Wu et al., 2019; Yang et al., 2021). However, it is worth noting that inorganic calcium has low bioavailability as it tends to form insoluble precipitates in the intestine (Zhang & Liu, 2022). Besides, intake of inorganic calcium often results in adverse side effects such as constipation and flatulence (Naciu et al., 2022).…”