枸杞多肽的制备及其抗氧化活性研究

Study on preparation and antioxidant activity of the Lycium barbarum polypeptide

研究了中性蛋白酶和木瓜蛋白酶复合水解制备枸杞活性肽的工艺条件,并采用离子交换层析和凝胶柱层析对酶解产物进行纯化,以制备具有较高抗氧化活力的枸杞多肽.以DPPH·清除率为指标,通过响应面优化得到最佳酶解工艺条件:酶解温度51℃,中性蛋白酶与木瓜蛋白酶质量比1∶2.65,酶解时间4.3 h,p H=7.0.此条件下得到的枸杞多肽对DPPH·清除率为(23.32±0.47)%.分别采用DEAE阴离子交换层析和Sephadex G-25凝胶柱层析对枸杞多肽进行分离,最终获得DPPH·和OH·清除率分别为(72.65±1.84)%和(58.72±1.88)%的A-1组分,该组分的DPPH·清除能力、ABTS+·清除能力和OH·清除能力均随浓度的增大而提高.

Enzymatic preparation conditions of Lycium barbarum bioactive peptides which were derived from hydrolyzation by compound of neutral protease and papain were studied. And then enzymatic hydrolysate was purified by ion-exchange column chromatography and gel filtration chromatography in order to prepare antioxidative bioactive peptides. Based on the DPPH · radical scavenging rate,the preparation method was optimized by response surface methodology. The optimal temperature,composite enzyme quality ratio,time and p H were 51 ℃,1∶2. 65,4. 3 h and 7. 0,which resulted in a DPPH· radical scavenging rate of（ 23. 32 ±0. 47） %. Then the enzymatic hydrolysate flowed through anion-exchange chromatography and sephdex G-25 gel chromatography in order to get purified polypeptide. Component A-1 was acquired which had the DPPH·and OH· removal rate of（ 72. 65 ± 1. 84） % and（ 58. 72 ± 1. 88） % respectively. DPPH·,ABTS ＋ · and OH· radical scavenging activity of protein peptide A-1 increased with the increase of concentration.