山楂果胶的抗氧化活性

目的：研究山楂果胶的体内外抗氧化活性。方法：离体条件测定山楂果胶对O2-·、DPPH自由基和·OH的清除能力;利用高脂小鼠模型考察山楂果胶在生物体内的总抗氧化能力。结果：山楂果胶离体条件对O2-·、DPPH自由基和·OH表现出显著的清除作用。山楂果胶能显著提高小鼠肝脏谷胱甘肽（glutathione,GSH）的含量和抗氧化酶类谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）、超氧化物歧化酶（superoxide dismutase,SOD）和过氧化氢酶（catalase,CAT）的活性,并可显著降低小鼠肝脏丙二醛（malondialdehyde,MDA）的含量。结论：山楂果胶具有显著的体内外抗氧化活性,在功能食品等领域具有良好的应用前景。     

鮟鱇鱼皮胶原蛋白肽的抗氧化活性

选取铁离子还原体系和3 种自由基体系为指标,研究鮟鱇鱼皮胶原蛋白肽体外清除自由基效果和抗氧化作用。采用超滤膜分离鮟鱇鱼皮胶原蛋白肽组分,筛选出体外清除•OH活性最好的组分,再建立小鼠衰老模型,将分离得到活性最好的组分采用灌胃法,测定小鼠皮肤中超氧化物歧化酶（superoxide dismutase,SOD）、过氧化氢酶（catalase,CAT）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）及丙二醛（malondialdehyde,MDA）和羟脯氨酸（hydroxyproline,Hyp）的含量,研究鮟鱇鱼皮胶原蛋白肽体内抗氧化和清除自由基作用。结果表明：鮟鱇鱼皮胶原蛋白肽具有较强的还原能力且对O－2•、DPPH自由基、•OH具有清除效果,质量浓度为10 mg/mL时对•OH、DPPH自由基、O－2•的清除率和对Fe3+ 的还原能力分别为70.48%、68.78%、42.53%和0.676;分子质量小于2 000 D的鮟鱇皮胶原蛋白肽组分对•OH具有较好的清除效果,IC50为15.7 mg/mL;剂量为100 mg/（kg•d）时,显著提高了皮肤中SOD、GSH-Px、CAT的活性,较模型组分别增加20.9%、41.3%和58.1%,且显著抑制MDA的形成。     

仿刺参精酶解工艺的优化及酶解液的抗氧化活性

作为性腺的仿刺参精富含蛋白质、多糖和多种活性物质,被单独收集并酶解,用于开发新型的海洋活性多肽。选用木瓜蛋白酶水解仿刺参精,以水解度(DH)为评价标准,通过单因素实验和响应面法确定最佳水解条件。当木瓜蛋白酶与底物质量比为4.4%时,在70 ℃条件下反应4 h,水解度最高可达到43.18%。随后,采用Pall Minimate超滤系统从酶解液中分离梯度肽,得到分子质量范围分别为<1 ku、1~5 ku和5~10 ku的多肽,测定它们对超氧自由基(·O₂-)和羟基自由基(·OH)的清除效率。抗氧化试验结果显示,分子质量<1 ku的多肽对·O₂-的清除能力最强,表明该肽段具有较好的抗氧化活性。仿刺参精的水解产物作为一种具有抗氧化活性的海洋多肽,有望用于保健品、医药和化妆品行业。     

鲍内脏多糖体内抗氧化及增强小鼠免疫活性

为研究鲍内脏多糖（abalone visceral polysaccharides,AVP）体内抗氧化及增强小鼠免疫活性作用,采用 乙醇氧化损伤模型动物实验设计和正常小鼠增强小鼠免疫力实验设计,通过测定实验小鼠肝脏超氧化物歧化酶 （superoxide dismutase,SOD）活力,谷胱甘肽（glutathione,GSH）、丙二醛（malondialdehyde,MDA）和蛋白 质羰基含量综合评价AVP的体内抗氧化能力;通过测定正常实验小鼠免疫器官指数、足跖增厚、溶血素抗体水平、 吞噬指数α,从免疫器官指数、细胞免疫、体液免疫以及非特异性免疫方面综合评价AVP增强小鼠免疫活性能力。 结果表明：AVP显著提高氧化损伤模型小鼠肝脏SOD活力和GSH含量（P＜0.05）,显著降低小鼠肝脏MDA含量和 蛋白质羰基含量（P＜0.05）,表现出良好的体内抗氧化能力;AVP能极显著提高正常小鼠脾脏指数和胸腺指数、 足跖增厚和血清溶血素水平（P＜0.01）,显著提升小鼠吞噬指数（P＜0.05）,在免疫器官指数、细胞免疫、体液 免疫以及非特异性免疫4 个方面均表现出较好的增强小鼠免疫活性效果;另外,数据表明AVP体内抗氧化及增强小 鼠免疫活性作用与其剂量呈正相关性。鲍内脏多糖是一种具有良好的抗氧化和增强免疫活性的物质,为鲍内脏的精 深加工与产业化开发提供了理论依据。     

清酱肉多肽的抗氧化活性和氨基酸分析

以清酱肉为研究对象,提取并通过超滤分离得到清酱肉多肽（分子质量＜10 kDa）,测定不同质量浓度多肽液对1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基、羟自由基（·OH）的清除效果、Fe2＋螯合能力和还原能力,分析清酱肉多肽的氨基酸组成。结果表明：当清酱肉多肽液的质量浓度为5 mg/mL时,其对·OH和DPPH自由基的清除率分别可达51.49%和57.50%,与相同质量浓度的谷胱甘肽（glutathione,GSH）相比差异显著（P＜0.05）;清酱肉多肽的Fe2＋螯合能力随其质量浓度的增加而显著提高,当质量浓度为5 mg/mL时,其对Fe2＋的螯合率可达50.97%;清酱肉多肽还具有一定的还原性。此外,清酱肉多肽液的氨基酸组成较为丰富,其中必需氨基酸含量为29.14%;与抗氧化活性相关的碱性、酸性及疏水性氨基酸的总量达到87.75%。综上所述,清酱肉多肽液具有一定的抗氧化能力及营养价值。     

冬虫夏草对氧化损伤小鼠抗氧化作用研究

研究冬虫夏草对氧化损伤模型小鼠体内抗氧化能力的影响及作用机制。将60只小鼠随机分为空白组、模型组、维生素E阳性组、冬虫夏草高、中、低组,采用D-半乳糖连续背部注射建立小鼠氧化损伤模型。连续给各受试样品4周后,测定小鼠血清及肝、脑组织中丙二醛(malondialdehyde,MDA)、蛋白羰基、还原型谷胱甘肽(glutathione,GSH)含量,超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性及总抗氧化能力(total antioxidant activity,T-AOC);实时定量聚合酶链式反应法测定小鼠肝脏组织中SOD、GSH-Px mRNA表达水平。与模型组比较,冬虫夏草可明显降低小鼠血清中MDA、蛋白羰基含量,升高血清中GSH含量及SOD、GSH-Px、T-AOC活性;明显降低小鼠肝脏及脑组织中MDA含量,升高SOD、GSH-Px活性;明显升高小鼠肝脏组织中SOD、GSH-Px mRNA表达水平。冬虫夏草能明显提高氧化损伤小鼠的体内抗氧化能力,其机制可能与调节抗氧化酶基因表达有关。     

紫苏油在乙醇诱导氧化损伤模型小鼠体内的抗氧化作用

探索紫苏油作为抗氧化功能性食品的潜力,研究紫苏油在小鼠体内的抗氧化作用。给昆明小鼠每日灌胃不同剂量的紫苏油,饲养30 d后,除空白对照组外,其他实验组灌胃乙醇造成小鼠氧化损伤模型,并对小鼠肝脏丙二醛（malondialdehyde,MDA）、谷胱甘肽（glutathione,GSH）、蛋白质羰基（protein carbonyl,PC）含量和血清超氧化物歧化酶（superoxide dismutase,SOD）活力进行测定。结果表明：与模型组比较,空白对照组,100、200、400 mg/（kg•d）紫苏油剂量组小鼠肝脏的MDA含量分别降低了46.08%（P＜0.01）、17.28%（P＜0.05）、25.12%（P＜0.05）、48.16%（P＜0.01）;100 mg/（kg•d）紫苏油剂量组小鼠血清的SOD活力极显著增强（P＜0.01）;100、200 mg/（ k g • d）紫苏油剂量组小鼠肝脏的GSH含量极显著升高（P＜0.01）;100 mg/（kg•d）紫苏油剂量组小鼠肝脏的PC含量显著降低（P＜0.05）。因此,紫苏油在乙醇诱导氧化损伤模型小鼠的体内具有抗氧化作用,其通过降低小鼠肝脏内MDA、PC含量,提高GSH含量,升高血清SOD活力发挥作用,其中100 mg/（kg•d）为紫苏油推荐剂量,应进一步对其进行研究。     

植物乳杆菌NDC75017抗氧化活性研究

目的：研究酸奶中所筛选的植物乳杆菌（Lactobacillus plantarum）NDC75017在不同体系中的抗氧化作用模式。方法：测定了活细胞、无细胞提取物、胞外分泌物及菌体灭活物质的自由基清除能力、总抗氧化能力（totalantioxidant capacity,T-AOC）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）、总超氧化物歧化酶（total superoxide dismutase,T-SOD）活性、还原能力和金属离子螯合能力。结果：株菌能够耐受一定浓度的过氧化氢（H2O2）,无细胞提取物的超氧阴离子自由基（O2－•）和DPPH自由基清除能力最强,胞外分泌物的羟自由基（•OH）清除作用最好。无细胞提取物和胞外分泌物的T-AOC效果最佳,与另外两组差异显著（P＜0.05）。胞外分泌物的GSH-Px和T-SOD酶活性最高,明显比无细胞提取物和菌体灭活组效果好（P＜0.05）。4 组样品都具有还原能力和金属离子螯合能力,但Cu2+螯合能力不如Fe2+螯合能力效果好。结论：菌株具有抗氧化活性,其抗氧化本质可能与其具有金属离子螯合能力、提供电子和清除自由基等作用模式有关。     

南极磷虾油改善衰老小鼠抗氧化能力的作用研究

研究南极磷虾油对衰老小鼠抗氧化能力的改善作用。以雄性ICR 小鼠为研究对象,采用皮下注射D-半乳糖（500 mg/kg bw）方法建立小鼠衰老模型,正常组注射等体积生理盐水,造模6 周后,衰老模型小鼠根据血清丙二醛（malondialdehyde,MDA）水平分为模型组、不同剂量南极磷虾油组（50、150、300 mg/kg bw）,各南极磷虾油剂量组每日灌胃给予相应剂量南极磷虾油,正常组和模型组灌胃等体积大豆油,连续灌胃30 d 后,测定小鼠血清MDA 含量、超氧化物歧化酶（superoxide dismutase,SOD）活力、蛋白质羰基含量及全血还原型谷胱甘肽（reduced glutathione,GSH）含量。结果表明,模型组小鼠较正常组血清MDA 和蛋白质羰基含量显著升高（P＜0.05）、血清SOD 活力和全血GSH 水平显著降低（P＜0.01）。与模型组小鼠相比,南极磷虾油各剂量组均能提高血清SOD 活力和全血GSH 水平、降低血清MDA 和蛋白质羰基含量,且中、高剂量组效果显著（P＜0.05）。南极磷虾油可保护D-半乳糖所致衰老小鼠的氧化损伤,提高其抗氧化能力,起到延缓衰老的作用。     

裸燕麦球蛋白源多肽对D-半乳糖致衰老小鼠抗氧化能力的影响

研究裸燕麦球蛋白源多肽（peptide from naked oat globulin,PNOG）对D-半乳糖（D-galactose,D-gal）致衰老小鼠抗氧化能力的影响。采取连续6 周颈背部皮下注射D-gal 120 mg/（kg mb·d）建立小鼠亚急性衰老模型。将60 只小鼠随机分为正常对照组,衰老模型组,PNOG低、中、高剂量治疗组（200、600、1 000 mg/（kg mb·d））以及VC阳性对照组（100 mg/（kg mb·d））,皮下注射同时灌胃给药,每天1 次,连续6 周。6 周后测定小鼠体质量增量、肝及脑的脏器指数;血清中超氧化物歧化酶（superoxide dismutase,SOD）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）及过氧化氢酶（catalase,CAT）活力;肝、脑组织中GSH-Px、单胺氧化酶-B（monoamine oxidase B,MAO-B）活力及丙二醛（malondialdehyde,MDA）含量。结果表明：与正常对照组相比,衰老模型组小鼠体质量增加缓慢,脏器指数降低;血清中SOD、GSH-Px及CAT活力均显著降低（P＜0.05）;肝、脑组织中GSH-Px活力显著降低（P＜0.05）,MAO-B活性及MDA含量极显著升高（P＜0.01）。灌胃中、高剂量PNOG后,可使衰老小鼠体质量显著提高,脏器指数增大;与衰老模型组相比,可显著提高血清中SOD、GSH-Px及CAT活力及肝、脑组织中GSH-Px活力,极显著降低MAO-B活力以及MDA含量（P＜0.01）。表明PNOG能有效清除机体内产生的过量自由基,显著提高D-gal致衰老小鼠的抗氧化能力,具有量效关系。     

Purification and identification of antioxidant peptides from grass carp muscle hydrolysates by consecutive chromatography and electrospray ionization-mass spectrometry

Grass carp muscles were hydrolyzed with various proteases (papain, bovine pancreatin 6.0, bromelain, neutrase 1.5MG and alcalase 2.4L) to extract antioxidant peptides. The hydrolysates were assessed using methods of hydroxyl radical scavenging ability and lipid peroxidation inhibition activity. Hydrolysate prepared with alcalase 2.4L was found to have the highest antioxidant activity. It was purified using ultrafiltration and consecutive chromatographic methods including ion-exchange chromatography, multilayer coil high-speed counter-current chromatography, and gel filtration chromatography. The purified peptide, as a potent antioxidant, was identified as Pro-Ser-Lys-Tyr-Glu-Pro-Phe-Val (966.3 Da) using RP-HPLC connected on-line to an electrospray ionization mass spectrometry. As well, it was found that basic peptides had greater capacity to scavenge hydroxyl radical than acidic or neutral peptides and that hydrophobic peptides contributed more to the antioxidant activities of hydrolysates than the hydrophilic peptides. In addition, the amino acid sequence of the peptide might play an important role on its antioxidant activity.     

Flaxseed protein-derived peptide fractions: Antioxidant properties and inhibition of lipopolysaccharide-induced nitric oxide production in murine macrophages

A protein isolate was produced from cellulase-treated defatted flaxseed meal followed by hydrolysis with seven proteases and evaluation of the hydrolysates for antioxidant and anti-inflammatory properties. The flaxseed protein hydrolysates (FPH) were processed by ultrafiltration and ion-exchange chromatography to isolate low molecular weight (LMW) and cationic peptide fractions, respectively. The peptides showed antioxidant properties in scavenging 2,2-diphenyl-1-picrylhydrazyl radical, superoxide anion radical, electron-spin resonance-detected hydroxyl radical and nitric oxide. In addition, all peptide fractions inhibited semicarbazide-sensitive amine oxidase activity. Antioxidant activities of these peptides were dependent on the specificity of proteases and size of the resulting peptides. The LMW fractions from pepsin, ficin and papain FPH also inhibited lipopolysaccharide-induced nitric oxide productions in RAW 264.7 macrophages without apparent cytotoxicity; thus, these peptides may act as anti-inflammatory agents. Thus, flaxseed protein hydrolysates may serve as potential ingredients for the formulation of therapeutic products.     

Effect of degree of hydrolysis on the antioxidant activity of loach (Misgurnus anguillicaudatus) protein hydrolysates

Loach (Misgurnus anguillicaudatus) proteins were hydrolysed by papain and Protamex, the antioxidant activity of loach protein hydrolysates (LPH) was investigated. The results demonstrated that extensive hydrolysis by papain and Protamex led to the browning of the hydrolysates. When the degree of hydrolysis (DH) was 23%, hydrolysates prepared by papain (HA) exhibited the strongest antioxidant activity. The maximum values of the hydroxyl, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activities and the reducing power were 56.1%, 95.5%, 2.80 mM and 1.46, respectively. The hydrolysates prepared by Protamex (HB) showed the strongest hydroxyl radical scavenging activity (55.0%) at DH 28%, DPPH radical scavenging activity (92.2%) and ABTS radical scavenging activity (2.81 mM) at DH 23%, and the reducing power (1.17) at DH 33%. At the same DH value, there were significant (p < 0.05) differences between HA and HB. Several antioxidant amino acid residues, especially Trp and His, contributed significantly to the antioxidant activity of the hydrolysates. An increase of peptides with molecular weight below 500 Da was observed as the DH increased for all LPH. The above results indicated that DH and protease greatly influenced the molecular weight and amino acid residue composition of LPH, and further influenced the antioxidant activity.Industrial relevanceLoach has long been employed as a traditional Chinese medicine for the treatment of many kinds of diseases. From our previous work, loach was determined to be a good source of protein (accounts for approximately 17% (w/w) of the body weight). In this work, loach proteins were hydrolyzed by papain and Protamex to specific extent. The effect of DH on the antioxidant activities of hydrolysates was investigated. The results indicated that loach protein hydrolysates were potent antioxidants which were significantly affected by DH. This research is helpful for extensive development of loach product.     

波纹巴非蛤蛋白酶解产物的抗氧活性及分子量分布研究

以波纹巴非蛤为原料,分离得到肌浆蛋白、肌原纤维蛋白、基质蛋白3种蛋白组分,分别研究其氨基酸组成及其胰蛋白酶酶解产物的体外抗氧化活性及分子量分布。结果表明该三种蛋白质中必需氨基酸、碱性氨基酸、疏水性氨基酸和支链氨基酸含量较高。抗氧化实验结果显示,三种蛋白对DPPH自由基、羟基自由基和超氧阴离子自由基均有一定的清除效果,且清除率与酶解液浓度存在一定的量效关系。与其它两种蛋白酶解产物相比,肌浆蛋白酶解液中小分子肽含量最高,分子量小于1500 u占42.55±0.27%,其对自由基清除效果也明显高于其它两种蛋白酶解液,对DPPH自由基、羟基自由基和超氧阴离子自由清除活性的IC50值分别为4.82、4.70和3.75 mg/mL。肌浆蛋白和肌原纤维蛋白酶解产物的还原能力相当,浓度为10 mg/mL时,其OD700分别为0.58和0.57,基质蛋白酶解产物的还原能力较弱。     

罗非鱼肌浆蛋白源抗氧化肽的制备、分离纯化及其体外抗氧化活性

采用木瓜蛋白酶对罗非鱼肌肉蛋白组分(肌浆蛋白、肌原纤维蛋白、基质蛋白)进行酶解,研究罗非鱼不同蛋白组分酶解产物的抗氧化活性,并通过超滤、凝胶过滤色谱、反相高效液相色谱对高活性肌浆蛋白组分抗氧化肽进行分离纯化,同时对纯化后的抗氧化肽氨基酸组成予以分析.结果表明:罗非鱼肌浆蛋白酶解物(tilapia sarcoplasmi...     

Characterisation of antioxidant peptides from enzymatic hydrolysate of golden melon seeds protein

The purpose of present research was to study novel antioxidant peptides from Golden melon seeds. Alkaline protease was used to hydrolyse the Golden melon seeds protein to obtain the hydrolysed peptides. These antioxidant peptides were purified and identified by ultrafiltration, gel filtration chromatography and RP-HPLC-ESI-MS/MS. Results showed that the peptide fraction (GMSHp3) with molecular weight (MW) <3 kDa obtained by ultrafiltration had the highest antioxidant capacity. This fraction was further purified via gel filtration chromatography into six sub-fractions, among which GMSHp3-3 exhibited the highest hydroxyl radical scavenging effect. Fraction GMSHp3-3 was further purified via RP-HPLC-ESI-MS/MS and sequenced as six potential antioxidant peptides with amino acids sequences of RMSFPVMCRN, LMRVLAQLG, ALAPLVALPAA, LVGKPAPD, LPAAHKA and AHAAGYGG, among which LMRVLAQLG, LPAAHKA and AHAAGYGG possessed effective ferric reducing power. These results indicated that novel antioxidant peptides from golden melon seeds protein hydrolysates might be potential antioxidant source of functional foods or nutraceutical supplements.     

仿刺参纵肌多糖的纯化及体外抗氧化

目的：以仿刺参纵肌多糖为对象,探讨其纯化方法,并对其抗氧化活性进行研究。方法：仿刺参纵肌经木瓜蛋白酶水解、三氯乙酸去蛋白、Sephacryl S-400凝胶柱层析,得到一种多糖,进行红外光谱、分子质量和硫酸基含量测定,并进行硫酸酯化及体外抗氧化实验。结果：红外光谱初步显示所得纯化多糖具有酸性糖胺聚糖结构,分子质量约为676kD,硫酸基含量为10.98%,取代度为0.285;硫酸酯化后硫酸基含量为17.43%,取代度为0.360;纯化多糖及酯化多糖都具有抗氧化活性。结论：仿刺参纵肌多糖随着硫酸基含量及取代度的提高,抗氧化活性逐渐增强。     

Preparation and in vitro antioxidant activity of enzymatic hydrolysates from oyster (Crassostrea talienwhannensis) meat

Oyster is an abundant resource from ocean, which contains high content of protein. In the present study, oyster (Crassostrea talienwhannensis) meat was digested with three proteases including papain, neutrase and alcalase respectively and the derived hydrolysates were fractionated using a series of ultrafiltration membranes (molecular weight cut‐offs of 10, 5, 3 and 1 kDa). The resultant peptide fractions were evaluated for antioxidant activity using 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assay and reducing power assay. Results indicated that oyster meat hydrolysates (OMHs) possessed DPPH radical scavenging capacity and reducing power in a dose‐dependent manner. The fractions below 1 kDa showed the strongest overall antioxidant activity. The present study demonstrated that the antioxidant potent of OMHs was strongly related to their concentration, size and amino acid composition.     

大豆生物活性肽的分离及其抗氧化活性研究

为制各具有抗氧化活性的大豆生物活性肽,本实验采用酶解处理大豆蛋白粉,对酶解产物进行葡聚糖Sephadex G-25凝胶柱层析分离,并对其各组分分子量分布及其抗氧化性进行了研究,对抗氧化活性最佳的肽段进行氨基酸组成分析。结果显示,大豆蛋白酶解物经Sephadex G-25分离后得到了六个肽片段,其中平均链长为4,即含有2～6个氨基酸残基的大豆功能短肽SPP4,对羟自由基具有最佳的清除作用,清除率达到80．13%,氨基酸组成分析发现该组分中缬氨酸、亮氨酸、苯丙氨酸、赖氨酸含量较高。结果表明,含2～6个氨基酸残基的大豆生理活性短肽具有较好的抗氧化活性。     

黄粉虫抗氧化活性肽的分离纯化研究

为制备具有抗氧化活性的黄粉虫生物活性肽,采用双酶水解黄粉虫蛋白粉,对酶解产物进行葡聚糖SephadexG-25 凝胶柱层析和阳阴离子交换柱层析分离纯化,并对其各组分分子量分布及其抗氧化性进行研究,对抗氧化活性最佳的肽段进行氨基酸组成分析。结果显示,纯化得到的抗氧化多肽对羟自由基和超氧阴离子自由基具有很强的清除作用,清除率可分别达到74.20% 和87.32%。