美拉德反应对鱼蛋白酶解物抗氧化活性的影响

文章以鱼糜漂洗液回收蛋白酶解物为原料,分别与葡萄糖、D-果糖、蔗糖、乳糖反应制备美拉德反应产物,探讨美拉德反应对酶解物抗氧化活性的影响。以DPPH自由基清除率为指标,选出葡萄糖作为美拉德反应的最适糖,通过响应面优化试验得出最佳反应条件:加热温度为126.92℃、反应初始pH为10.39、反应时间为3.89h、葡萄糖浓度为3g/dL。在此条件下,羟基自由基清除能力从34.83%增加到61.82%,DPPH自由基清除能力、ABTS自由基清除能力和还原力也有所提高。因此,美拉德反应可以提高鱼糜漂洗液回收蛋白酶解物的抗氧化能力。     

酪蛋白与还原糖美拉德反应产物抗氧化性的研究

采用酪蛋白同还原糖（葡萄糖∶乳糖=1∶1）发生美拉德反应,研究其美拉德反应产物（MRPs）的抗氧化活性,测定了MRPs的还原力和对DPPH自由基的清除率。根据单因素及正交实验结果表明,酪蛋白与还原糖反应得到的美拉德反应产物的抗氧化活性同反应物浓度、反应温度、反应时间、反应起始pH存在一定的量效关系,并且确定酪蛋白浓度为3%、反应温度为100℃、反应时间为6h、反应起始pH10时是最佳美拉德反应模式,此时MRPs的抗氧化活性较强,DPPH·清除率可达72.87%。     

大豆肽的制备及其美拉德反应产物特性研究

本文以高温大豆粕为原材料,模拟酱油制曲工艺,通过发酵和酶解技术制备大豆肽,研究大豆肽及其美拉德反应产物的特性。通过比较其蛋白质回收率、DPPH自由基清除率等抗氧化指标、褐变程度及其肽分子量分布情况,深入研究了发酵酶解工艺和酶解时间对大豆肽及其美拉德产物抗氧化特性的影响。研究发现,发酵和酶解处理均可显著提升高温大豆粕的蛋白质回收率和抗氧化活性,在酶解时间为24 h时大豆粕的回收率达到最大值77.21%,此时大豆粕酶解产物的DPPH自由基IC50值和还原力(A700)分别为0.77 mg/m L和0.16。而美拉德反应则可以进一步提升大豆粕酶解产物的抗氧化活性。另外美拉德反应过程中分子质量较大的组分热降解反应比较剧烈,而小分子寡肽则比大分子多肽具有更高的美拉德反应活性。     

鲢鱼肽美拉德反应产物超滤组分的抗氧化活性研究

鲢鱼肽美拉德反应产物(MRPs)经5 k Da、1 k Da超滤膜分离、然后再经溶剂分级后,获得了不同组分,分析其抗氧化活性与理化特性。通过对不同组分的DPPH自由基清除活性、金属离子螯合活性和总抗氧化能力的测定可以看出,水溶性组分中的高分子量化合物比低分子量化合物具有较高抗氧化活性,而醇溶性组分中高分子量的抗氧化活性比低分子量的低。MRPs中水溶性组分F-3(5 k Da)对DPPH自由基清除活性、对金属离子的螯合活性和总抗氧化力最高;水溶性组分中F-3和F-2(1 k Da~5 k Da)的褐变程度较高,F-3的荧光强度最高;FI-IR分析发现,F-2和F-3在860.01 cm-1和948.61 cm-1处有强烈的吸收峰,这表明肽因美拉德反应发生了结构的变化。因此,鲢鱼肽MRPs中起主要抗氧化作用的为水溶性物质,且其中相对高分子量的有色水溶性产物抗氧化活性较强。     

罗非鱼鱼皮胶原肽-葡萄糖美拉德反应产物的制备及其抗氧化活性

制备了不同葡萄糖浓度条件下罗非鱼鱼皮胶原肽-葡萄糖美拉德反应体系,评价了不同体系中美拉德反应产物(MRPs)的特征和抗氧化活性。结果表明:加热1 h内反应体系的pH值均显著降低(P<0.05);MRPs在294nm处的吸光值和褐变强度的增加与游离氨基基团含量的降低一致;MRPs的荧光强度随加热时间的增加而显著增加(P<0.05)。相比较于胶原肽,MRPs对DPPH·和ABTS+·清除活性以及还原能力随加热时间的延长而迅速增强,但羟自由基清除活性无显著变化,这可能与MRPs的金属螯合活性相关。胶原肽氨基与葡萄糖羰基摩尔比为1∶2体系中的MRPs具有最高的自由基清除活性以及还原能力。     

葡萄糖-牡蛎酶解液美拉德反应体系的抗氧化活性

以牡蛎酶解液与葡萄糖建立美拉德反应体系,以1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl, DPPH）自由基清除率、金属离子螯合能力和还原能力为指标,通过葡萄糖质量分数、反应温度、pH值以及反应时 间4 个因素的单因素试验和正交试验优化得到具有强抗氧化活性的美拉德反应产物适宜反应条件。结果表明,葡萄 糖-牡蛎酶解液美拉德反应产物具有较强抗氧化活性的反应条件为葡萄糖质量分数4%、反应温度120 ℃、pH 7.0、 反应时间120 min。在此组合条件下,牡蛎酶解液美拉德反应得到的反应液的DPPH自由基清除率为93.2%,金属离 子螯合能力为22.5%,还原能力为1.436。     

紫苏粕抗氧化活性肽的制备及其糖基化修饰的研究

以紫苏粕为原料经石油醚脱脂,碱溶酸沉法提取蛋白,超声波复合酶法制备蛋白肽,美拉德反应进行糖基化修饰,以DPPH自由基清除率为考察指标,采用单因素试验优化紫苏蛋白肽的制备工艺,响应面分析试验优化糖基化产物制备的最佳工艺条件。结果表明,超声波3 min,功率500 W,辅助木瓜蛋白酶水解3 h,制得蛋白肽的DPPH自由基清除率达到96.70%;选取葡萄糖和蛋白肽的质量比值为1、pH 9.0、100℃下反应4 h,反应后的糖基化产物DPPH自由基清除率可达59.32%;以葡萄糖和蛋白肽的质量比值为1.25、90℃下反应4 h, DPPH自由基清除率达85.55%,为糖基化产物的最佳工艺条件。紫苏蛋白制备的抗氧化活性肽和糖基化产物均具有较高的抗氧化活性,蛋白肽经糖基化修饰后抗氧化活性显著提高。     

虾夷扇贝裙边酶解物美拉德反应产物的自由基清除活性

以虾夷扇贝裙边为原料,利用中性蛋白酶制备其酶解物及美拉德反应产物。扇贝裙边蛋白的条带主要分布在200,97 ku和42 ku。其经中性蛋白酶酶解3 h后,水解度达28.95％。将酶解物与核糖反应制备美拉德反应产物,并分析其抗氧化活性和风味物质组成。结果表明:美拉德反应生成较多的中间产物和褐色物质。经美拉德反应后,酶解物生成较多挥发性成分,尤其是杂环化合物种类增加。此外,酶解物的羟基和ABTS自由基清除能力仅分别为42.7％和31.64％,且未表现出明显的DPPH自由基清除能力。然而,经12 h的美拉德反应后,酶解物的羟自由基、DPPH和ABTS自由基清除能均力得到显著提高,表明扇贝裙边酶解物-核糖美拉德反应产物具有良好的抗氧化能力,可作为抗氧化剂应用于食品工业中。     

糖基化反应条件对鲢鱼鱼肉碱性蛋白酶解产物清除DPPH自由基的影响

为提高鲢鱼鱼肉蛋白酶解产物抗氧化活性,本研究将葡萄糖和低聚异麦芽糖通过糖基化反应分别引入到鲢鱼鱼肉蛋白碱性蛋白酶酶解产物中,利用分光光度计测定其清除DPPH自由基能力。研究结果表明碱性蛋白酶酶解产物与葡萄糖比例为2:1,在60℃时反应得到的产物清除DPPH能力显著高于50℃条件下的反应产物。鲢鱼鱼肉蛋白的碱性蛋白酶酶解物在一定条件下与葡萄糖反应可以提高其清除DPPH自由基能力。     

不同条件下美拉德反应产物抗氧化活性的研究综述

美拉德反应产物不仅在许多种类食品的颜色、风味、稳定性和货架期等方面发挥着重要作用,且具有多种多样的生物活性如抗氧化、抗诱变、抗病毒、抗增殖、降血压等,其中某些产物的抗氧化活性甚至可与常用的食品抗氧化剂相媲美。目前对美拉德反应产物抗氧化活性的研究已经成为热点。综述了在实际体系、模拟体系下不同反应底物、溶剂、加工技术等条件下美拉德反应产物的抗氧化活性,分别通过自由基(DPPH自由基、羟基自由基、ABTS自由基、超氧阴离子自由基)清除能力、还原能力、金属离子(Fe2+,Cu2+)螯合能力等考察其抗氧化活性。并且指出深入研究美拉德反应产物具有抗氧化活性的关键物质是什么?其作用机制如何?是研究美拉德反应产物抗氧化性的未来发展方向。     

酪蛋白-木糖体系美拉德反应产物的抗氧化活性

研究评价了由酪蛋白-木糖模拟体系产生的美拉德反应产物的抗氧化活性,考察了反应过程中体系的pH、褐变和中间产物的变化,并测定了美拉德反应产物对金属离子(Cu2+和Fe2+)的螯合能力、自由基清除能力(.OH、DPPH.和ABTS.)以及其还原能力。结果表明,模拟体系的酸度和褐变均随反映的进行而逐渐增加,中间产物在反应初期大量形成;美拉德反应产物对Fe2+的螯合能力要明显强于对Cu2+的螯合能力;美拉德反应产物对DPPH.和ABTS.具有较强的清除作用,而对.OH的清除作用较弱;美拉德反应产物的还原能力随反应时间的延长而逐渐增大。     

Effect of substrate ratios and temperatures on development of Maillard reaction and antioxidant activity of silver carp (Hypophthalmichthys molitrix) protein hydrolysate–glucose system

The study of antioxidant activity of the hydrolysates is necessary during its processing in which Maillard reaction would often occur. To understand the effect of Maillard reaction on antioxidant activity of silver carp protein hydrolysates (SPH), the Maillard reaction products (MRPs) were prepared at different ratios between SPH and glucose by Maillard reaction in powdered state, respectively. MRPs possessed a strong 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity and reducing power (P < 0.05). The hydrolysate and glucose heated with the ratio of 2:1 at 60 °C showed high browning intensity and good antioxidant properties (P < 0.05). According to the correlation coefficients of variables included in the hydrolysate–glucose system, good correlations were observed among the antioxidant activities, the absorbance at 294 nm and the loss of free amino groups. The results suggested that Maillard reaction has a good potential to improve the antioxidant activity of SPH.     

Antioxidant activity of Maillard reaction products derived from aqueous glucose/glycine,diglycine, and triglycine model systems as a function of heating time

The purpose of this study was to evaluate the antioxidant activity of Maillard reaction products (MRPs) derived from aqueous glucose/glycine, diglycine, and triglycine model systems as a function of heating time. The pH of MRPs derived from the Glu-G model system decreased markedly as the heating time increased, while MRPs derived from the Glu-Di model system showed the highest increase in absorbance at 420 nm. MRPs derived from the Glu-G model system showed the highest cupric ion chelating ability, while MRPs derived from the Glu-Di model system had the highest ferrous ion chelating activity. MRPs derived from the Glu-Di model system were found to be effective antioxidants in different in vitro assays with regard to the 2,2′-azinobis(3-ethylbenothiazoline-6-sulphonic acid) diammonium salt (ABTS) and 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activities and ferric reducing/antioxidant power (FRAP).     

Biological activities and physicochemical properties of Maillard reaction products in sugar–bovine casein peptide model systems

The purpose of this study was to evaluate the biological activities and physicochemical properties of Maillard reaction products (MRPs), derived from aqueous reducing sugar (ribose, galactose and lactose) and bovine casein peptide (BCP) model systems. The fluorescence intensity of ribose-BCP MRPs reached the maximum value within 1 h, while it took 3 h for galactose-BCP MRPs. Size exclusion chromatography of all the MRPs indicated molecular rearrangements and production of new smaller molecules, as a function of the heating time. The consumption of ribose and amino groups was the highest in the ribose-BCP MRPs. BCP lost its known angiotensin-I-converting enzyme (ACE) inhibitory activity by the Maillard reaction with reducing sugars. Ribose–BCP MRPs had the lowest ACE inhibitory activity, but they showed the highest 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity and ferrous reducing power among all the MRPs. Galactose-BCP MRPs inhibited, slightly the growth of Caco-2 cells, while ribose-BCPand lactose-BCP MRPs had no cytotoxicity.     

Characteristics and antioxidant activity of ultrafiltrated Maillard reaction products from a casein–glucose model system

Maillard reaction products (MRPs) were prepared from casein–glucose by refluxing for 130 min at 102 °C and initial pH 12.0 without pH control to investigate the characteristics of casein–glucose Maillard reaction and the antioxidant activity difference among different fractions of MRPs. Browning and intermediate products increased, however, the pH of the system decreased with increase in the heating time. Free amino group content decreased 78% during first 10 min and did not change nearly thereafter. Amino acid analysis indicated that lysine and arginine decreased significantly, and casein was partially hydrolysed to peptides or free amino acid. High molecular weight compounds were dominant in the MRPs, determined by high performance gel-filtration chromatography. After ultrafiltration, antioxidant activity of each MRPs fraction was investigated by DPPH radical-scavenging activity, reducing power, Fe²⁺ chelating activity and lecithin oxidation assay. MRPs of different molecular weight exhibited distinctly different antioxidant activities.     

The inhibition effects of reactive oxygen species by Maillard reaction products in Caco‐2 cells

Maillard reaction products (MRPs) were prepared by heating a mixture of rice starch with different dextrose equivalents (DE 10, 30, 50 and 70) and glycine. The glycine was added to the sample pastes at the same molar concentration as the sugar contained in each sample. As the dextrose equivalent of rice starch increased, the browning intensity and fluorescence of the MRPs increased. The antioxidant properties of the MRPs were investigated by DPPH radical scavenging activity, reducing power, and phenolic content in a chemical system, and were evaluated by measuring reactive oxygen species levels and antioxidant enzymes activities in Caco‐2 cells. The darkest MRPs, MRPs‐4, showed the highest antioxidant activity and phenolic content among the samples; in addition, it inhibited the cellular oxidative stress. The decrease of cell viability and antioxidant enzymes activities caused by reactive oxygen species and apoptosis were recovered by MRPs‐4. Actually, the addition of the MRPs suppressed apoptosis by decreasing the proportion of cells in the sub‐G1 phase. Therefore, these MRPs, as compounds formed by the Maillard reaction, are considered to possess an effective antioxidant activity against oxidizable substrates.     

花蟹肉酶解物美拉德反应产物的抗氧化性

为研究花蟹肉酶解物美拉德反应产物(MRPs)的理化性质和功能属性,用花蟹肉酶解物(P)分别与木糖(X)、葡萄糖(G)、乳糖(L)和果糖(F)进行模式美拉德反应,并测定MRPs的褐变程度和pH值变化,同时通过对MRPs进行DPPH自由基清除能力、还原能力、OH自由基清除能力和Fe2+螯合能力的测定,评价其抗氧化能力。结果表明,随着加热时间的延长,各MRPs的褐变程度增加,pH值下降,DPPH自由基清除能力、还原能力和OH自由基清除能力逐渐增加,但各MRPs的Fe2+螯合能力下降。还原糖种类不同,MRPs的抗氧化性不同,各MRPs的DPPH自由基清除能力、还原能力和OH自由基清除能力由强到弱依次为:木糖-花蟹肉酶解物(X-P)、果糖-花蟹肉酶解物(F-P)、葡萄糖-花蟹肉酶解物(G-P)、乳糖-花蟹肉酶解物(L-P)。