超声预处理时间对金枪鱼皮酶解过程ACE抑制肽释放的影响

以水解度、ACE抑制率为指标,并通过电泳、HPLC、红外光谱(FTIR)、热稳定性分析(DSC)研究不同超声预处理时间对金枪鱼皮酶解过程ACE抑制肽释放的影响。结果表明,酶解5 min后,超声预处理组酶解液的水解度与未处理组呈现显著性差异(p<0.05),并且ACE抑制率均高于未处理组,说明超声预处理可改变金枪鱼皮胶原酶解模式,加快短时酶解过程中ACE抑制肽的快速释放。电泳和HPLC分析表明,随着酶解过程的进行,10 kDa以下小分子组分含量呈现往复增减变化,超声预处理会加速该过程进行,从而提高其释放效率。FTIR和DSC分析可知,超声处理会破坏鱼皮胶原蛋白内部氢键的平衡,使其三螺旋结构松散,更多酶切位点暴露,说明超声处理能促进短时酶解过程ACE抑制肽的快速释放。

Effect of Ultrasonic Pretreatment Time on the Release of ACE Inhibitory Peptides Derived from Tuna Skin during Enzymatic Hydrolysis

The effect of different ultrasonic pretreatment time on the release of tuna skin-derived ACE inhibition peptides during enzymatic hydrolysis was investigated using hydrolysis degree and ACE inhibition rate by electrophoresis,HPLC,fourier transform infrared spectroscopy(FTIR)and differential scanning calorimetry(DSC). Results showed that the hydrolysis degree of the hydrolyzate in the ultrasonic pretreatment group was significantly different from that in the untreated group(p<0.05)after hydrolyzed for 5 min,and the ACE inhibition rate was higher than that of untreated group,indicating that the mode of tuna skin collagen hydrolysis was changed by ultrasonic pretreatment to promote the rapid release of collagen ACE inhibition peptides during short-term hydrolysis. Electrophoresis and HPLC results showed that the content of small molecular components below 10 kDa varied with the enzymatic hydrolysis process,which was accelerated by ultrasound pretreatment. FTIR and DSC showed that the internal hydrogen bonds and the triple helix structure of tuna skin collagen could be destroyed by ultrasound pretreatment,which was contributed to the expose of restriction site of triple-helix region and accelerated the release of ACE inhibition peptides during short-term hydrolysis.