Delaney Bryan, Nicolosi Robert J, Wilson Thomas A, Carlson Ting, Frazer Scott, Zheng Guo-Hua, Hess Richard, Ostergren Karen, Haworth James, Knutson Nathan
Cargill Health and Food Technologies, Wayzata, MN 55391, USA.
J Nutr. 2003 Feb;133(2):468-75. doi: 10.1093/jn/133.2.468.
The cholesterol-lowering activities of oats and barley are commonly attributed to the beta-glucan fractions. Although beta-glucan is present in both grains and appears to be chemically similar, the effect of source on cholesterol-lowering activity has not been evaluated. In the present study, the antiatherogenic properties of beta-glucan concentrates from oats and barley were evaluated in Syrian golden F(1)B hamsters consuming a semipurified hypercholesterolemic diet (HCD) containing cholesterol (0.15 g/100 g), hydrogenated coconut oil (20 g/100 g) and cellulose (15 g/100 g). After a 2-wk lead-in period, control hamsters were fed the HCD, whereas experimental hamsters consumed HCD formulated to include beta-glucan (2, 4, or 8 g/100 g) by addition of beta-glucan concentrate prepared from oats or barley at the expense of cellulose. Compared with control hamsters, dose-dependent decreases that were similar in magnitude in plasma total and LDL cholesterol concentrations were observed in hamsters fed beta-glucan from either source at wk 3, 6 and 9. Compared with controls, liver cholesterol concentrations were also reduced (P < 0.05) in hamsters consuming 8 g/100 g oat or barley beta-glucan. In agreement with previously proposed mechanisms, total fecal neutral sterol concentrations were significantly increased (P < 0.05) in hamsters consuming 8 g/100 g barley or oat beta-glucan. Aortic cholesterol ester concentrations were significantly reduced (P < 0.05) in hamsters fed 8 g/100 g beta-glucan from barley or oats. Although aortic total cholesterol and cholesterol ester concentrations were significantly correlated with LDL cholesterol (r = 0.565, P < 0.004 and r = 0.706, P < 0.0001, respectively), this association could explain only half of the variability. This study demonstrated that the cholesterol-lowering potency of beta-glucan is approximately identical whether its origin was oats or barley.
燕麦和大麦的降胆固醇活性通常归因于β-葡聚糖部分。虽然β-葡聚糖在这两种谷物中都存在,并且在化学性质上似乎相似,但尚未评估其来源对降胆固醇活性的影响。在本研究中,对叙利亚金黄F(1)B仓鼠食用含胆固醇(0.15 g/100 g)、氢化椰子油(20 g/100 g)和纤维素(15 g/100 g)的半纯化高胆固醇饮食(HCD)时,燕麦和大麦β-葡聚糖浓缩物的抗动脉粥样硬化特性进行了评估。经过2周的导入期后,对照仓鼠喂食HCD,而实验仓鼠食用通过添加由燕麦或大麦制备的β-葡聚糖浓缩物(2、4或8 g/100 g)以替代纤维素而配制的HCD。与对照仓鼠相比,在第3、6和9周时,喂食来自任何一种来源β-葡聚糖的仓鼠血浆总胆固醇和低密度脂蛋白胆固醇浓度出现了剂量依赖性下降,且下降幅度相似。与对照组相比,食用8 g/100 g燕麦或大麦β-葡聚糖的仓鼠肝脏胆固醇浓度也降低了(P < 0.05)。与先前提出的机制一致,食用8 g/100 g大麦或燕麦β-葡聚糖的仓鼠粪便中性固醇总浓度显著增加(P < 0.05)。喂食8 g/100 g来自大麦或燕麦β-葡聚糖的仓鼠主动脉胆固醇酯浓度显著降低(P < 0.05)。虽然主动脉总胆固醇和胆固醇酯浓度与低密度脂蛋白胆固醇显著相关(分别为r = 0.565,P < 0.004和r = 0.706,P < 0.0001),但这种关联仅能解释一半的变异性。这项研究表明,无论β-葡聚糖的来源是燕麦还是大麦,其降胆固醇效力大致相同。