Changes of the Content and Antioxidant Activity of Natural Peptides in Germinated Soybeans

[Objective]This study aimed to investigate the content and antioxidant activity of natural peptides in various soybean sprouts during the germination process. [Method]By using black soybean sprouts,yellow soybean sprouts and green soybean sprouts as raw materials,the content,DPPH· clearance rate,OH· clearance rate and reduction capacity of natural peptides in various soybean sprouts at different germination time were determined,to evaluate the antioxidant capacity of natural peptides and compare it with that of VC. [Result]The results showed that the contents of natural peptides in black soybean sprouts,yellow soybean sprouts and green soybean sprouts varied at different germination time. To be specific,the content of natural peptides in black soybean sprouts reached the maximum of 0. 194 mg /g at 2 d post-germination; the content of natural peptides in yellow soybean sprouts reached the maximum of 0. 231 mg /g at 2 d post-germination; the content of natural peptides in green soybean sprouts exhibited a negative correlation with the germination time,which reached the maximum of 0. 164 mg /g at 1 d post-germination. [Conclusion]According to the determination of DPPH· clearance rate,OH· clearance rate and reduction capacity of natural peptides in three varieties of soybean sprouts,natural peptides in yellow soybean sprouts possess the highest antioxidant activity,followed by those in black soybean sprouts.