桑叶粉中钙的含量测定及生物利用

目的:以四川大竹县所产桑叶为研究材料,对桑叶粉中钙含量进行测定,并对生物利用性进行探究。方法:对桑叶粉中总钙含量及氨基酸种类和含量进行测定,并对不同形态的钙含量进行测定;通过模拟胃部及肠道消化法研究桑叶粉的生物利用性。结果:样品中含钙量达到1614.85 mg/100 g,其水溶性钙、果胶钙和碳酸钙接近钙总含量的60%;桑叶粉可在胃酸作用下缓慢释放钙离子,与碳酸钙和葡萄糖酸钙相比,可减轻对胃的刺激,在肠道中其钙透过率显著(p<0.05)高于碳酸钙和葡萄糖酸钙;桑叶粉中氨基酸种类丰富,比例适当,EAA/TAA=40.79%,EAA/NEAA=68.88%,接近FAO/WHO标准模式。结论:桑叶粉中含有多种形态的钙且总钙量丰富,桑叶粉中的钙质更易被人体吸收。

Determination of calcium in mulberry leaf powder and its bioavailability

Objective:To study the content of calcium in mulberry leaf powder by using mulberry leaves produced in Dazhu County,Sichuan Province,and to explore the bioavailability.Methods:The total calcium content and amino acid categories and content of mulberry leaf powder were determined,and the calcium content of different forms was measured.The bioavailability of mulberry leaf powder was studied by simulating gastric and intestinal digestion. Results:The calcium content in the samples reached 1614.85 mg/100 g,the water-soluble calcium,pectin calcium and calcium carbonate were close to 60% of the total calcium content.The mulberry leaf powder could slowly release calcium under the action of gastric acid Ion,which can reduce the stimulation of the stomach compared to calcium carbonate and calcium gluconate. And the calcium permeability in the intestine was significantly higher than that of calcium carbonate and calcium gluconate (p<0.05). Mulberry leaf powder contains a wide variety of amino acids with appropriate proportion,EAA/TAA=40.79%,EAA/NEAA=68.88%,which was close to the FAO/WHO standard model. Conclusion:Mulberry leaf powder contains a variety of calcium forms, and the total calcium content is rich,and the calcium in mulberry leaves powder is more easily absorbed by the human body.