鲍内脏蛋白肽抗氧化和免疫调节活性

摘要

以鲍内脏为原料,通过碱性蛋白酶酶解,结合超滤方法,制备了鲍内脏蛋白肽样品.经高效液相色谱检测,分子质量主要分布在192～938 Da,占比76.3％.鲍内脏蛋白肽具有一定的体外自由基清除能力,对1,1-二苯基-2-三硝基苯肼自由基的最大清除率为32.7％,对羟自由基清除率的半抑制浓度为2.1 mg/mL,对自由基的清除效果远低于VC.鲍内脏蛋白肽具有较好的体内抗氧化活性,能极显著增强受伤小鼠体内超氧化物歧化酶(superoxide dismutase,SOD)活力和提高还原型谷胱甘肽(reduced glutathione,GSH)含量,明显降低丙二醛(malonaldehyde,MDA)和蛋白质羰基含量,鲍内脏蛋白肽中剂量组SOD活力和GSH含量分别提高了33.2％和1.3倍,MDA和蛋白质羰基含量分别降低43.9％和40.7％,其效果己接近或超过了阳性对照的水平,且呈现一定的剂量效应关系.免疫活性实验结果表明,与空白对照组相比,鲍内脏蛋白肽中剂量组小鼠足跖增厚提高了77.1％,抗体水平提高了28.0％,脾脏指数提高24.9％,胸腺指数提高了1.2倍,鲍内脏蛋白肽可以从细胞免疫、体液免疫、非特异性免疫、免疫器官4个方面增强小鼠免疫功能,且效果优于阳性对照.%Peptides were prepared by enzymatic hydrolysis of abalone visceral proteins with alcalase followed by ultrafiltration.The molecular weights of most peptides were in the range of 192-938 Da as measured by high performance liquid chromatography (HPLC),accounting for 76.3％ of the total.The peptides were able to scavenge free radicals in vitro but the activity was much weaker than that of vitamin C (VC).The maximum percentage of DPPH radical scavenging activity was 32.7％,and the half maximal inhibitory concentration (IC50) for hydroxyl radical scavenging was 2.1 mg/mL.Furthermore,the peptides exhibited significant antioxidant activity in vivo by increasing the activity of superoxide dismutase (SOD) and the content of glutathione (GSH) in injured mice,and reducing the contents of malonaldehyde (MDA) and protein carbonyl group content in a dose-dependent manner.The peptides augmented SOD activity and GSH content by 33.2％ and 130％,and decreased MDA and protein carbonyl group content by 43.9％ and 40.7％,respectively.The effect was close to or even better than that of the positive control.The immunomodulatory activity assay proved that the peptides increased voix pedis swelling by 77.1％,antibody level by 28.0％,splenic index by 24.9％ and spleen index by 120％.Accordingly,we concluded that the peptides derived from abalone visceral proteins could enhance immune function in mice with respect to cellular immunity,humoral immunity,nonspecific immunity and immune organs and the effect was better than that of the positive control.