鯖魚鹽溶性蛋白質酵素水解物之抗氧化性研究

Studies on Antioxidative Activity of Mackerel salt-soluble Protein Enzymatic Hydrolysates

本研究以鯖魚肉之鹽溶性蛋白質為原料，經加熱處理後進行水解，探討酵素水解物胜肽類之生成及其抗氧化性。二種鯖魚肉水解物之總游離胺基酸含量隨著水解時間增長而增加，而Protease N的水解效果較自家消化者為佳；雙胜肽類之甲肌肽及肌肽在自家消化水解物中未發現，但經Protease N水解後，則略有增加之趨勢。胜肽類之複合胺基酸總量經0.5~4小時水解後急遽增加，爾後隨時間之增長有減少的現象，Protease N水解物之複合胺基酸含量較自家消化水解物多。可容性蛋白質含量亦隨水解時間的延長而逐漸減少。二種酵素水解物在抗氧化能力方面，皆以Protease N之抗氧化效果優於白家消化，其中又以水解4小時之抗氧化效果較佳。統計分析顯示鯖魚肉水解物抗氧化能力之強弱與胜肽類之複合胺基酸含量有關。

The objectives of this research were to study the peptides from the enzymatic hydrolysates of mackerel salt-soluble protein via theremal treatment and their antioxidant activity. The total free amino acids of two hydrolysates increased with the hydrolysis time. The increase rate of Protease N was higher than that autolysis. The histidine-related dipeptides, anserine and carnosine were found in the Protease N hydrolysates and increased with the hydrolysis time, but were not detected in autolysates. The total combined amino acids of hydrolysates increased significantly during 0.5~4 hr hydrolysis and thereafter decreased. The increase rate of Protease N was higher than that of autolysis. The soluble protein decreased with the hydrolysis time. In the antioxidative activity, the Protease N hydrolysates had stronger antioxidative activity than that by autolysis and 4 hr hydrolysis had the highest ability. The positive correlation between the antioxidative activity and levels of combined amino acids of the hydrolys sate indicated that small peptide might be an important factor influencing the antioxidative activity.