Institute of Animal Science, Department of Nutrition Physiology and Products Quality, Přátelství 815, Prague 22, 104 00, Czech Republic; Czech University of Life Sciences, Faculty of Agrobiology, Food and Natural Resources, Department of Microbiology, Nutrition and Dietetics, Kamýcká 129, Prague 6, 165 21, Czech Republic.
Institute of Animal Science, Department of Nutrition Physiology and Products Quality, Přátelství 815, Prague 22, 104 00, Czech Republic.
Int J Biol Macromol. 2017 Dec;105(Pt 1):620-624. doi: 10.1016/j.ijbiomac.2017.07.077. Epub 2017 Jul 20.
Alginate is a copolymer of β-d-mannuronate and α-l-guluronate, which are present in the cell wall of brown algae. The hypocholesterolemic and hypolipidemic activities of alginate and its derivative, which is prepared by a reaction with octadecylamine, were compared in rats fed diets containing cholesterol and palm fat at 10 and 50g/kg, respectively. Amidated alginate at 20g/kg significantly decreased serum cholesterol from 2.93 to 2.00μmol/mL, serum triacylglycerols from 1.66 to 0.92μmol/mL, hepatic cholesterol from 17.5 to 5.9μmol/g, and total hepatic lipids from 67.4 to 51.7mg/g. Alginate at 20g/kg significantly reduced hepatic cholesterol to 13.1μmol/g, but did not influence serum cholesterol, triacylglycerols, and total hepatic lipids. Amidated alginate significantly increased the faecal concentrations of neutral sterols from 98.7 to 122.4μmol/g DM, but decreased faecal concentration of bile acids from 19.4 to 14.0μmol/g DM. In samples of intestinal contents, taurine-conjugated bile acids dominated glycine conjugates. The supplementation of diets with cholesterol significantly increased the expression of hepatic cholesterol 7α-hydroxylase, especially in rats that received cholesterol without alginate or amidated alginate. In conclusion, amidated alginate is an effective hypocholesterolemic agent that is more efficient than its parent polysaccharide.
藻酸盐是β-d-甘露糖醛酸和α-l-古洛糖醛酸的共聚物，存在于褐藻细胞壁中。在分别以胆固醇和棕榈油作为饲料的 10 和 50g/kg 的大鼠中，比较了藻酸盐及其与十八烷基胺反应制备的衍生物的降胆固醇和降血脂活性。20g/kg 的酰胺化藻酸盐可显著降低血清胆固醇水平，从 2.93μmol/ml 降至 2.00μmol/ml，血清三酰甘油水平从 1.66μmol/ml 降至 0.92μmol/ml，肝胆固醇从 17.5μmol/g 降至 5.9μmol/g，总肝脂质从 67.4mg/g 降至 51.7mg/g。20g/kg 的藻酸盐可显著降低肝胆固醇至 13.1μmol/g，但对血清胆固醇、三酰甘油和总肝脂质无影响。酰胺化藻酸盐可显著增加中性固醇在粪便中的浓度，从 98.7μmol/g DM 增至 122.4μmol/g DM，而降低胆汁酸在粪便中的浓度，从 19.4μmol/g DM 降至 14.0μmol/g DM。在肠内容物样本中，牛磺酸结合的胆汁酸占甘氨酸结合胆汁酸的主导地位。在添加胆固醇的饮食中，肝胆固醇 7α-羟化酶的表达显著增加，特别是在未添加藻酸盐或酰胺化藻酸盐的大鼠中。综上所述，酰胺化藻酸盐是一种有效的降胆固醇剂，其效果优于其母体多糖。
