钙的生物利用度与多肽螯合钙研究进展

钙是人体内十分重要的营养元素，对维持人体健康起到了至关重要的作用。小肠是钙吸收的主要部位，食物中的钙经胃酸溶解为离子形式后在微碱性的肠道环境内可能会形成沉淀，导致钙的吸收下降和生物利用度降低。而长期钙摄入不足则会导致佝偻病、骨质疏松症等一系列骨代谢疾病。因此，选择能够提供高可溶性和生物利用度的钙的食物或补充剂十分重要。部分有机钙盐如葡萄糖酸钙、柠檬酸钙等可以在肠道中形成过饱和溶液从而增强钙的吸收。此外，多肽螯合钙也被证实有非常好的钙吸收率和生物利用度，可以作为新型的钙补充剂。本文综述了食物基质成分对钙吸收和生物利用度的影响，并对部分有机钙盐和多肽螯合钙的促钙吸收机理进行了总结，旨在为钙的吸收与钙补充剂的研发提供新的思路。

Preparation of cattle bone collagen peptides-calcium chelate and its structural characterization and stability

Calcium is an essential nutrient for human health and plays a crucial role in various physiological processes such as bone formation, muscle contraction, nerve transmission, and blood clotting. Calcium absorption mainly occurs in the small intestine where the calcium enters the enterocytes through active transport or passive diffusion. However, the free calcium ions dissolved in gastric acid may form insoluble precipitates with other dietary components (such as phytate, oxalate, fiber) in the slightly alkaline intestinal environment, leading to decreased calcium absorption and bioavailability. Decreased calcium absorption can result in a range of bone metabolic diseases, such as rickets and osteoporosis. Therefore, it is important to choose foods or supplements that can provide highly soluble and bioavailable forms of calcium. Some organic calcium salts such as calcium gluconate and calcium citrate have been shown to form supersaturated solutions in the intestinal tract, which can enhance calcium absorption by increasing the concentration gradient across the intestinal epithelium. Furthermore, calcium-peptide complexes are proven to be very effective for improving calcium absorption without causing any side effects. Calcium-peptide complexes can serve as a novel calcium supplement. In this paper, the effects of food components on calcium absorption and bioavailability are reviewd, and the mechanisms underlying the enhancement of calcium absorption by some organic salts (such as calcium gluconate and calcium citrate) and peptides are summarized. And the potential applications of calcium-peptide complexes in human nutrition are also discussed, aiming to provide new insights that can aid in the development of safe and effective calcium supplements