鲍内脏多糖的抗氧化活性

为研究鲍内脏多糖的抗氧化活性,采用体外抗氧化实验,评价不同化学组成的鲍内脏多糖对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和·OH的清除作用,并以人体肝细胞LO2建立过氧化氢损伤模型,探讨鲍内脏多糖在细胞水平的抗氧化能力。结果表明:鲍内脏多糖CAVP、AVP1、AVP2具有良好的清除体外自由基能力。多糖CAVP、AVP1、AVP2清除DPPH自由基的半抑制率浓度(half maximal inhibitory concentration,IC50)分别为1.46、1.74、1.55 mg/m L。其清除·OH的IC50分别为7.14、15.27、8.11 mg/m L。另外,细胞模型法评价结果显示,鲍内脏多糖CAVP、AVP1、AVP2在质量浓度0.5~4.0 mg/m L条件下对肝细胞LO2的H2O2氧化损伤有保护作用,3种多糖样品均能显著提高LO2细胞存活率;CAVP(4.0 mg/m L)、AVP1(0.5 mg/m L)和AVP2(0.5 mg/m L)能极显著降低氧化损伤时乳酸脱氢酶的释放;CAVP能极显著提高LO2细胞内谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)(4.0 mg/m L)、过氧化氢酶(catalase,CAT)(0.5 mg/m L)、超氧化物歧化酶(superoxide dismutase,SOD)(0.5 mg/m L)活力;AVP1质量浓度为4.0 mg/m L时,能极显著提高LO2细胞内GSH-Px、SOD活力,显著提高CAT活力;AVP2分别在质量浓度0.5、4.0 mg/m L时极显著提高LO2细胞内CAT活力;在质量浓度为4.0 mg/m L时,3种多糖样品对降低细胞氧化损伤产生的丙二醛(malondialdehyde,MDA)均有显著作用。因此,鲍内脏多糖是一类潜在的抗氧化物,可用于此类功能食品的开发。

Antioxidant Activity of Polysaccharides from Abalone Viscera

The antioxidant capacity of polysaccharides extracted from abalone viscera was studied by measuring their 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical scavenging capacity and their ability to protect human liver LO2 cells against H2O2-induced oxidative damage. The results demonstrated that the crude polysaccharide (CAVP) and two purified fractions (AVP1 and AVP2) all had apparent free radical scavenging capacity with a half maximal inhibitory concentrations (IC50) of DPPH radical scavenging activity of 1.46, 1.74 and 1.55 mg/mL, respectively, and an IC50 of hydroxyl radical scavenging activity of 7.14, 15.27 and 8.11 mg/mL, respectively. In addition, all three polysaccharides in the concentration range from 0.5 to 4.0 mg/mL could protect LO2 cells against H2O2-induced oxidative damaged as indicated by significantly increased survival rate and CAVP at 4.0 mg/mL, AVP1 at 0.5 mg/mL and AVP2 at 0.5 mg/mL decreased the activity of lactic dehydrogenase (LDH) in cell culture supernatant. CAVP significantly increased the intracellular activities of glutathione peroxidase (GSH-Px) at 4.0 mg/mL, catalase (CAT) at 0.5 mg/mL and superoxide dismutase (SOD) at 0.5 mg/mL. AVP1 at 4.0 mg/mL resulted in a significant elevation in CAT activity and a highly significant increase in GSH-Px and SOD activities. AVP2 at both 0.5 and 4.0 mg/mL could highly significantly increase CAT activity. All three polysaccharides at 4.0 mg/mL could significantly reduce the content of malondialdehyde (MDA) as a lipid peroxidation product. Therefore, abalone visceral polysaccharides could be used as potential antioxidant ingredients in functional foods.