摘要:
以珍珠龙胆石斑鱼为研究对象,采用静态体外消化模型模拟胃肠道消化,研究硒代蛋氨酸对珍珠龙胆石斑鱼肌原纤维蛋白体外消化特性的影响。结果表明:经模拟胃、肠消化后,高水平硒代蛋氨酸组(Y2组)的硒含量(0.130 mg/kg、0.072 mg/kg)显著高于对照组(C组)和低水平硒代蛋氨酸组(Y1组)(P<0.05),而羰基含量(2.02 nmol/mg、2.59 nmol/mg)、二聚酪氨酸含量(3962 a.u、4062 a.u、硫代巴比妥酸(TBA)值(0.31 mg/kg、0.32 mg/kg)和粒径(365 nm、357 nm)显著低于C组和Y1组(P<0.05),且其紫外吸收峰值和内源荧光强度更高,说明高水平硒代蛋氨酸延缓了肌原纤维蛋白的氧化变性过程,更好地维持了肌原纤维蛋白消化过程中的结构稳定性。Y1组的体外消化率(62.19%、67.25%)和水解度(0.31 mmol/g、0.34mmol/g)显著高于C组和Y2组(P<0.05)。因此,硒代蛋氨酸的添加不仅能显著提升珍珠龙胆石斑鱼肌原纤维蛋白的抗氧化能力,还可有效改善其体外消化特性,即硒代蛋氨酸在提高鱼类蛋白营养品质和稳定性方面具有潜在的应用价值。
Abstract:
In this study, the effects of selenomethionine on the in vitro digestibility of myofibrillar protein (MP) of pearl gentian grouper were studied by using a static in vitro digestion model to simulate gastric and intestinal digestion. The results showed as follows: after simulated gastric and intestinal digestion, the selenium content of high-level selenomethionine group (Y2 group) (0.130 mg/kg, 0.072 mg/kg) was significantly higher than that of control group (C group) and low-level selenomethionine group (Y1 group) (P < 0.05). However, the carbonyl content (2.02 nmol/mg, 2.59 nmol/mg), dityrosine content (3962 a. u. , 4062 a. u.), thiobarbituric acid (TBA) value (0.31 mg/kg, 0.32 mg/kg), and particle size (365 nm, 357 nm) of Y2 group were significantly lower than those in C group and Y1 group (P < 0.05). Besides, the UV absorption peaks and endogenous fluorescence intensities of the Y2 group were higher. The results showed that high-level selenomethionine delayed MP′s oxidation and denaturation process,and better maintained the structure of MP during digestion. The in vitro digestibility (62.19%, 67.25%) and the degree of hydrolysis (0.31 mmol/g, 0.34 mmol/g)of the Y1 group were significantly higher than those of the C group and Y2 group (P < 0.05). In conclusion, the supplementation of selenomethionine not only improves the antioxidant capacity of MP but also improves its in vitro digestibility, indicating that selenomethionine has potential application in improving the nutritional quality and stability of fish protein.