富硒双孢蘑菇硒形态分布及其营养品质和抗氧化特性

为了研究硒对双孢蘑菇子实体硒形态分布、营养品质和抗氧化酶活性的影响,通过在栽培实验中添加不同用量Na_2SeO_3的方式培养双孢蘑菇。采用原子荧光光谱法测定富硒双孢蘑菇子实体中的硒含量,分析硒在子实体中的分布情况,并以普通双孢蘑菇为对照,对富硒双孢蘑菇的主要营养成分及抗氧化酶活性进行测定。结果表明,双孢蘑菇子实体中的硒含量与培养料中硒用量呈正相关,蛋白硒含量占有机硒含量的比例约为77%~87%,蛋白质是双孢蘑菇的主要硒载体。硒用量为40 mg/kg时,可溶性蛋白和总糖含量较对照组显著增加;硒用量较高时,可溶性蛋白和总糖含量较对照组显著降低。随着硒用量的增加,总氨基酸含量和丙二醛含量增加,超氧化物歧化酶活性增强,而过氧化氢酶活性较低。本实验研究表明,适宜的硒用量可以提高双孢蘑菇子实体中硒含量,有助于改善其营养品质和生理特性。

Selenium Speciation Distribution,Nutritional Quality and Antioxidant Activity of Se-Enriched Agaricus bisporus

The objective of this study was to determine the selenium speciation distribution, nutritional quality and antioxidant enzyme activity of Agaricus bisporus growing on mushroom beds with different amounts of selenium salt (Na2SeO3). The selenium content and speciation distribution were analyzed by atomic fluorescence spectrometry (AFS). The soluble protein, total sugar and malondialdehyde (MDA) contents as well as the activities of superoxide dismutase (SOD) and hydrogen peroxidase (CAT) were measured using non-Se-enriched A. bisporus as the control. Results showed that the addition of Na2SeO3 led to a significant (P < 0.05) increase in selenium content in the fruit bodies of A. bisporus. Protein-bound selenium accounted for 77%–87% of the total organic selenium, demonstrating protein to be the main carrier of organic selenium. The addition of 40 mg/kg selenium to the compost resulted in an increase in the contents of soluble protein and total sugar compared to the control group, whereas a significant decrease in the two parameters was observed at higher concentration of selenium. With the increase in added selenium concentration, the contents of free amino acid and MDA and SOD activity were increased while CAT activity was reduced. These results showed that the optimal range of selenium concentration could enhance the selenium content of A. bisporus, thereby improving the nutritional quality and physiological properties.