Reiter Russel J, Manchester L C, Tan Dun-xian
Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, Texas, USA.
Nutrition. 2005 Sep;21(9):920-4. doi: 10.1016/j.nut.2005.02.005.
We investigated whether melatonin is present in walnuts (Juglans regia L.) and, if so, tested whether eating walnuts influences melatonin levels and the total antioxidant status of the blood.
Melatonin was extracted from walnuts and quantified by high-performance liquid chromatography. After feeding walnuts to rats, serum melatonin concentrations were measured using a radioimmunoassay and the "total antioxidant power" of the serum was estimated by using the trolox equivalent antioxidant capacity and ferric-reducing ability of serum methods.
Mean +/- standard error melatonin concentrations were 3.5 +/- 1.0 ng/g of walnut. After food restriction of rats and then feeding them regular chow or walnuts, blood melatonin concentrations in the animals that ate walnuts were increased over those in the rats fed the control diet. Increases in blood melatonin were also accompanied by increases in trolox equivalent antioxidant capacity and ferric-reducing ability of serum values.
Melatonin is present in walnuts and, when eaten, increase blood melatonin concentrations. The increase in blood melatonin levels correlates with an increased antioxidative capacity of this fluid as reflected by augmentation of trolox equivalent antioxidant capacity and ferric-reducing ability of serum values.
我们研究了核桃（胡桃）中是否存在褪黑素，如果存在，测试食用核桃是否会影响血液中的褪黑素水平和总抗氧化状态。
从核桃中提取褪黑素，并通过高效液相色谱法定量。给大鼠喂食核桃后，使用放射免疫分析法测量血清褪黑素浓度，并使用血清的Trolox等效抗氧化能力和铁还原能力方法估算血清的“总抗氧化能力”。
核桃中褪黑素的平均浓度为3.5±1.0纳克/克。对大鼠进行食物限制后，再给它们喂食普通食物或核桃，食用核桃的动物血液中的褪黑素浓度高于喂食对照饮食的大鼠。血液中褪黑素的增加还伴随着血清Trolox等效抗氧化能力和铁还原能力值的增加。
核桃中存在褪黑素，食用后会增加血液中的褪黑素浓度。血液中褪黑素水平的增加与该液体抗氧化能力的增加相关，这通过血清Trolox等效抗氧化能力和铁还原能力值的增加得以体现。
