• 【(S,S)-和 (R,R)-甲磺酸钠二葡糖苷 (SDGs) 的合成及抗氧化评价。】 复制标题 收藏 收藏
    DOI:10.1016/j.bmcl.2013.07.062 复制DOI
    作者列表:Mishra OP,Simmons N,Tyagi S,Pietrofesa R,Shuvaev VV,Valiulin RA,Heretsch P,Nicolaou KC,Christofidou-Solomidou M
    BACKGROUND & AIMS: :Secoisolariciresinol diglucosides (SDGs) (S,S)-SDG-1 (major isomer in flaxseed) and (R,R)-SDG-2 (minor isomer in flaxseed) were synthesized from vanillin via secoisolariciresinol (6) and glucosyl donor 7 through a concise route that involved chromatographic separation of diastereomeric diglucoside derivatives (S,S)-8 and (R,R)-9. Synthetic (S,S)-SDG-1 and (R,R)-SDG-2 exhibited potent antioxidant properties (EC50=292.17±27.71 μM and 331.94±21.21 μM, respectively), which compared well with that of natural (S,S)-SDG-1 (EC50=275.24±13.15 μM). These values are significantly lower than those of ascorbic acid (EC50=1129.32±88.79 μM) and α-tocopherol (EC50=944.62±148.00 μM). Compounds (S,S)-SDG-1 and (R,R)-SDG-2 also demonstrated powerful scavenging activities against hydroxyl [natural (S,S)-SDG-1: 3.68±0.27; synthetic (S,S)-SDG-1: 2.09±0.16; synthetic (R,R)-SDG-2: 1.96±0.27], peroxyl [natural (S,S)-SDG-1: 2.55±0.11; synthetic (S,S)-SDG-1: 2.20±0.10; synthetic (R,R)-SDG-2: 3.03±0.04] and DPPH [natural (S,S)-SDG-1: EC50=83.94±2.80 μM; synthetic (S,S)-SDG-1: EC50=157.54±21.30 μM; synthetic (R,R)-SDG-2: EC50=123.63±8.67 μM] radicals. These results confirm previous studies with naturally occurring (S,S)-SDG-1 and establish both (S,S)-SDG-1 and (R,R)-SDG-2 as potent antioxidants and free radical scavengers for potential in vivo use.
    背景与目标: : secoisolicistrisulinol二葡糖苷 (SDGs) (S,S)-SDG-1 (亚麻籽中的主要异构体) 和 (R,R)-SDG-2 (亚麻籽中的次要异构体) 由香草醛经由secoisolaricyresinol (6) 和葡萄糖基供体7通过涉及非对映异构体二葡萄糖苷衍生物 (S,S)-8和 (R,R)-9的色谱分离的简洁途径合成。合成的 (S,S)-SDG-1和 (R,R)-SDG-2表现出有效的抗氧化性能 (分别为EC50 = 292.17 ± 27.71微米和331.94 ± 21.21微米),与天然 (S,S)-SDG-1 (EC50 = 275.24 ± 13.15微米) 相比。这些值明显低于抗坏血酸 (EC50 = 1129.32 ± 88.79微米) 和 α-生育酚 (EC50 = 944.62 ± 148.00微米) 的值。化合物 (S,S)-SDG-1和 (R,R)-SDG-2也显示出强大的清除羟基活性 [天然 (S,S)-SDG-1: 3.68 ± 0.27; 合成 (S,S)-SDG-1: 2.09 ± 0.16; 合成 (R,R)-SDG-2: 1.96 ± 0.27],过氧 [天然 (S,S)-SDG-1: 2.55 ± 0.11; 合成 (S,S)-SDG-1: 2.20 ± 0.10; 合成 (R,R)-SDG-2: 3.03 ± 0.04] 和DPPH [天然 (S,S)-SDG-1: EC50 = 83.94 ± 2.80微米; 合成 (S,S)-SDG-1: EC50 = 157.54 ± 21.30微米; 合成 (R,R)-SDG-2: EC50 = 123.63 ± 8.67微米] 自由基。这些结果证实了先前对天然存在的 (S,S)-SDG-1的研究,并确立了 (S,S)-SDG-1和 (R,R)-SDG-2作为潜在的体内使用的有效抗氧化剂和自由基清除剂。
  • 【蜂蜜甜型腰果苹果花蜜的抗氧化和诱变活性评价。】 复制标题 收藏 收藏
    DOI:10.1016/j.fct.2013.08.026 复制DOI
    作者列表:da Silva RA,Dihl RR,Nascimento e Santos D,de Abreu BR,de Lima A,de Andrade HH,Lehmann M
    BACKGROUND & AIMS: :In vitro chemical properties and antioxidant potential and in vivo mutagenic activity of honey-sweetened cashew apple nectar (HSCAN), a beverage produced from the cashew pseudo-fruit (Anacardium occidentale L.) and of its constituents were assessed. Analytical procedures were carried out to investigate the honey used in the HSCAN preparation, and the results observed are in accordance with Brazilian legal regulations, except for diastase number. HSCAN and pulp were investigated for ascorbic acid, carotenoid, anthocyanin and total phenolic contents, and both showed high acid ascorbic concentrations. Antioxidant capacity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and/or β-carotene/linoleic acid systems were applied and demonstrated a weak antioxidant capacity of honey and HSCAN, but cashew apple pulp demonstrated high antioxidant capacity. A weakly positive mutagenic effect of cashew pulp 20% was observed using the somatic mutation and recombination test (SMART) in Drosophila melanogaster only in the high-bioactivation (HB) cross. On the contrary, HSCAN was not mutagenic in both standard and high bioactivation crosses. HSCAN exhibited slight antioxidant activity, which could be associated with the high amount of ascorbic acid found in the samples evaluated. The beverage prepared did not induce DNA damage in somatic cells of D. melanogaster, which means that it is neither mutagenic nor recombinagenic in this test system.
    背景与目标: : 评估了用腰果假果 (Anacardium occidentale L.) 生产的饮料蜂蜜甜味腰果苹果花蜜 (HSCAN) 的体外化学特性,抗氧化潜力和体内诱变活性及其成分。进行了分析程序以调查HSCAN制剂中使用的蜂蜜,观察到的结果符合巴西法律法规,但淀粉酶编号除外。研究了HSCAN和纸浆中的抗坏血酸,类胡萝卜素,花青素和总酚含量,两者均显示出较高的抗坏血酸浓度。使用2,2-二苯基-1-微肼基自由基 (DPPH) 和/或 β-胡萝卜素/亚油酸体系进行了抗氧化能力,表明蜂蜜和HSCAN的抗氧化能力较弱,但腰果苹果浆具有较高的抗氧化能力。仅在高生物活化 (HB) 杂交中,使用果蝇的体细胞突变和重组试验 (SMART) 观察到腰果果肉20% 的弱阳性诱变作用。相反,HSCAN在标准和高生物活化杂交中均没有诱变。HSCAN表现出轻微的抗氧化活性,这可能与评估样品中发现的大量抗坏血酸有关。制备的饮料不会诱导黑腹大白鼠体细胞的DNA损伤,这意味着它在该测试系统中既没有诱变性也没有重组性。
  • 【运动训练和慢性乙醇摄入对大鼠肝脏和血浆抗氧化系统的相互作用。】 复制标题 收藏 收藏
    DOI:10.1002/(sici)1099-1263(199705)17:3<189::aid-jat43 复制DOI
    作者列表:Husain K,Somani SM
    BACKGROUND & AIMS: This study was undertaken in order to investigate the interactive effects of exercise training and chronic ethanol consumption on the antioxidant system in rat liver and plasma. Fisher-344 rats were treated in separate groups as followssedentary control (SC); exercise training (ET) for 6.5 weeks; ethanol 20% (2.0 g kg-1, p.o.) for 6.5 weeks; and ET and ethanol administration. In liver, ET significantly decreased the malondialdehyde (MDA) level (73% of SC). Chronic ethanol significantly increased catalase (CAT) activity and MDA levels (126% and 135% of SC), respectively, and also depleted the reduced glutathione (GSH) level and the reduced to oxidized glutathione (GSH/GSSG) ratio (81% and 38% of SC), respectively. Exercise training plus ethanol significantly increased CAT and glutathione reductase (GR) activity (126% and 118% of SC), respectively, and decreased the MDA level (67% of SC). In plasma, ethanol significantly enhanced CAT activity and MDA levels (173% and 221% of SC), respectively. Ethanol ingestion also increased the CAT/superoxide dismutase (SOD) ratio (216% of SC) in plasma. Training plus ethanol ingestion significantly increased CAT activity and MDA levels (208% and 148% of SC), respectively, and increased CAT/SOD and glutathione peroxidase (GSH-Px)/SOD ratios (279% and 142% of SC), respectively. The data indicate that the combination of exercise and ethanol ingestion resulted in an enhanced hepatic CAT and GR activity to eliminate H2O2 and to maintain endogenous GSH levels. Thus, training ameliorated the ethanol-induced oxidative injury in the liver. The ratio of CAT/SOD in plasma increased twofold due to chronic ethanol intake and threefold due to the combination, which may be used as an index of oxidative stress.

    背景与目标: 进行这项研究是为了研究运动训练和慢性乙醇消耗对大鼠肝脏和血浆抗氧化系统的相互作用。将Fisher-344的大鼠分为不同的组作为以下对照 (SC); 运动训练 (ET) 6.5周; 乙醇20% (2.0g kg-1,p.o.) 6.5周; 和ET和乙醇给药。在肝脏中,ET显着降低了丙二醛 (MDA) 水平 (SC的73%)。慢性乙醇分别显著增加过氧化氢酶 (CAT) 活性和MDA水平 (SC的126% 和135%),并且还分别耗尽还原型谷胱甘肽 (GSH) 水平和还原型谷胱甘肽 (GSH/GSSG) 比 (SC的81% 和38%)。运动训练加乙醇分别显着增加CAT和谷胱甘肽还原酶 (GR) 活性 (SC的126% 和118%),并降低MDA水平 (SC的67%)。在血浆中,乙醇分别显着提高CAT活性和MDA水平 (SC的173% 和221%)。乙醇摄入也增加了血浆中的CAT/超氧化物歧化酶 (SOD) 比 (SC的216%)。训练加乙醇摄入分别显着增加CAT活性和MDA水平 (SC的208% 和148%),并分别增加CAT/SOD和谷胱甘肽过氧化物酶 (gsh-px)/SOD比率 (SC的279% 和142%)。数据表明,运动和乙醇摄入的结合导致肝CAT和GR活性增强,以消除H2O2并维持内源性GSH水平。因此,训练改善了乙醇诱导的肝脏氧化损伤。血浆中CAT/SOD的比例由于长期摄入乙醇而增加了两倍,由于该组合而增加了三倍,这可能用作氧化应激的指标。
  • 【Γ 辐射对棉铃虫酚氧化酶途径,抗氧化防御机制的影响 (鳞翅目: 夜蛾科) 及其对遗传不育对害虫抑制的影响。】 复制标题 收藏 收藏
    DOI:10.3109/09553002.2013.835500 复制DOI
    作者列表:Sachdev B,Zarin M,Khan Z,Malhotra P,Seth RK,Bhatnagar RK
    BACKGROUND & AIMS: PURPOSE:To investigate age-correlated radiosensitivity in highly radioresistant lepidopteran pest, Helicoverpa armigera, upon exposure to ionizing radiation and to examine the irradiation impact on stress-molecular responses in F1 (first-filial) progeny of irradiated (100 Gy) male moths in relation to its reproductive behavior. MATERIALS AND METHODS:Efficacy of sub-lethal gamma radiation was evaluated on two markedly apart ontogenic stages, neonates and adult moths. Differential growth, reproductive behavior and stress-indicating molecular responses were examined upto F1 progeny of sub-sterilized moths. Free-radical scavenging enzymes, superoxide dismutase (SOD), catalase (CAT) and Phenoloxidase cascade enzymes, pro-phenoloxidase (PPO), its activating enzyme (PPAE) were studied in irradiated and irradiated plus microbial challenge regimen (dual-stress) by Real-time RT-PCR (reverse-transcription-polymerase-chain-reaction). RESULTS:An inverse correlation of radiosensitivity with developmental age of insect was observed. F1 sterility was higher than parent sterility. F1 progeny exhibited protraction in development and decreased survival upon irradiation. Sex ratio in F1 progeny was skewed towards males. PPO, PPAE, SOD and CAT transcripts were downregulated upon neonate irradiation resulting in enhanced vulnerability of larvae to incidental microbial challenge. These transcripts were upregulated in F1 progeny of sub-sterilized male moths (100 Gy) upon dual-stress. CONCLUSIONS:Irradiation impact on stress-indicating molecular responses in F1 progeny is correlated with its reproductive performance. These observations will permit defining regimen having pragmatic viability of 'F1 sterility technique' for pest suppression. Gamma dose of 100 Gy would ensure balance between induced sterility of males and their field competitiveness. These parameters would facilitate integration of biocontrol strategy with parabiological 'Sterile Insect Release Technique'.
    背景与目标:
  • 【由酸面团分离物Weissella cibaria med17产生的 α-D-葡聚糖的结构和理化特性及抗氧化活性。】 复制标题 收藏 收藏
    DOI:10.1016/j.ijbiomac.2020.06.030 复制DOI
    作者列表:Aburas H,İspirli H,Taylan O,Yilmaz MT,Dertli E
    BACKGROUND & AIMS: :An exopolysaccharide (EPS) producer slimy-mucoid type colony was isolated from sourdough and identified as Weissella cibaria MED17. The 1H and 13C NMR spectra of EPS MED17 demonstrated that this EPS was a dextran type glucan ((1 → 6)-linked α-D-glucose core structure) containing (1 → 3)-linked α-D-glucose branches and proportion of (1 → 6)-linked α-D-glucose units to (1 → 3)-linked α-D-glucose units was 94.3:5.7%. The FTIR analysis also confirmed the (1 → 6)-linked α-D-glucose linkage. A high level of thermal stability was observed for glucan MED17 as no degradation up to 300 °C was observed by TGA and DSC analysis. The XRD analysis of glucan MED17 showed its semi- crystalline nature and its compact sheet-like morphology was observed by SEM analysis. Finally, antioxidant characteristics of glucan MED17 were determined by ABTS and DPPH radical scavenging activity tests that revealed a moderate antioxidant activity of glucan MED17. These findings show potential techno-functional characteristics of glucan MED17.
    背景与目标: : 从酸面团中分离出胞外多糖 (EPS) 生产者粘液粘液型菌落,并鉴定为Weissella cibaria med17。EPS MED17的1h和13C NMR光谱表明,该EPS是葡聚糖型葡聚糖 ((1 → 6)-连接的 α-D-葡萄糖核心结构),包含 (1 → 3)-连接的 α-D-葡萄糖分支和 (1 → 6)-连接的 α 的比例-D-葡萄糖单位与 (1 → 3)-连接的 α-D-葡萄糖单位94.3:5.7%。FTIR分析还证实了 (1 → 6) 连接的 α-D-葡萄糖连接。对于葡聚糖MED17观察到高水平的热稳定性,因为通过TGA和DSC分析未观察到高达300 °C的降解。葡聚糖MED17的XRD分析表明其半结晶性质,并通过SEM分析观察到其致密的片状形态。最后,通过ABTS和DPPH自由基清除活性测试确定了葡聚糖MED17的抗氧化特性,表明葡聚糖MED17具有中等的抗氧化活性。这些发现显示了葡聚糖med17的潜在技术功能特征。
  • 【深入了解海洋真菌天然化合物的抗氧化和光保护特性。】 复制标题 收藏 收藏
    DOI:10.1021/acs.jcim.9b00964 复制DOI
    作者列表:Dao DQ,Phan TTT,Nguyen TLA,Trinh PTH,Tran TTV,Lee JS,Shin HJ,Choi BK
    BACKGROUND & AIMS: :This computational and experimental work aims to elucidate physicochemical and photophysical natures of free radical scavenging and ultraviolet radiation (UVR) filtering activities of five terpenoids available in the extract of marine fungus. The antioxidant activities of ochraceopone F (C1), aspertetranone D (C2), cycloechinulin (C3), wasabidienone E (C4), and mactanamide (C5) are evaluated by using density functional theory (DFT) at the M05-2X/6-311++G(d,p) level of theory in the gas phase, water, and pentyl ethanoate (PEA). Double antioxidant mechanisms allowing the second (H+/e-) donation such as double hydrogen atom transfer (dHAT), double single electron transfer-proton transfer (dSET-PT), and double sequential proton loss-electron transfer (dSPL-ET) are considered. Reaction enthalpies (ΔrH0), standard Gibbs free energies (ΔrG0) and potential energy surfaces of reactions toward HOO• radical are then established to evaluate the hydrogen transfer (HT) and radical adduct formation (RAF) mechanisms. The computational results are supported by DPPH• and ABTS•+ antioxidant essays. Results show that all compounds C1-C5 are able to scavenge two free radicals via dHAT, dSET-PT, and dSPL-ET mechanisms. Among the compounds, C3 and C4 represent the most potential antioxidants, especially via HAT and RAF mechanisms in all the reaction media. Their rate constants for both HAT and RAF reactions are remarkably higher than that of Trolox and ascorbic acid. The kinetic calculations on activation Gibbs free energies (ΔG⧧) and rate constants (kTST) based on conventional transition state theory (TST) reveal that HAT and RAF processes are in competition in solvents. Photophysical processes occurring during UVR exposure are investigated using the time dependent density functional theory (TD-DFT) combined with UV-vis experiments. The obtained results highlight the promising activities of C1-C5 in UVR absorption in the ranges of UVA and UVB. Among them, C3 and C4 also show better UV absorption properties with the easiest excitations (band gaps equal to 4.06 and 3.65 eV). This study suggests the natural candidates possibly used in organic sunscreen.
    背景与目标: : 这项计算和实验工作旨在阐明海洋真菌提取物中五种萜类化合物的自由基清除和光物理性质和紫外线辐射 (UVR) 过滤活性。利用密度泛函理论 (DFT) 在M05-2X/6-311G (D,p) 气相,水和戊基乙酸酯 (PEA) 的理论水平。允许第二次 (H/e-) 捐赠的双重抗氧化剂机制,例如双氢原子转移 (dHAT),双单电子转移-质子转移 (dSET-PT) 和双顺序质子损失-电子转移 (dspl-et) 被考虑。然后建立反应焓 (ΔrH0),标准吉布斯自由能 (ΔrG0) 和向HOO • 自由基反应的势能面,以评估氢转移 (HT) 和自由基加合物形成 (RAF) 机理。计算结果得到DPPH·和ABTS·+ 抗氧化论文的支持。结果表明,C1-C5的所有化合物都能够通过dHAT,dSET-PT和dspl-et机制清除两个自由基。在这些化合物中,C3和C4代表了最有潜力的抗氧化剂,尤其是在所有反应介质中通过HAT和RAF机理。HAT和RAF反应的速率常数均显着高于Trolox和抗坏血酸。基于常规过渡态理论 (TST) 的活化吉布斯自由能 (Δ g ⧧) 和速率常数 (kTST) 的动力学计算表明,HAT和RAF过程在溶剂中竞争。使用时间相关的密度泛函理论 (td-dft) 结合UV-vis实验研究了UVR暴露过程中发生的光物理过程。获得的结果突出了在UVA和UVB范围内C1-C5在UVR吸收中的有希望的活性。其中,C3和C4还在最容易激发 (带隙等于4.06和3.65 eV) 的情况下显示出更好的UV吸收性能。这项研究表明,可能用于有机防晒霜的天然候选物。
  • 【Nrf2-induced抗氧化保护: 对抗ROS介导的神经退行性疾病损伤的有希望的靶标?】 复制标题 收藏 收藏
    DOI:10.1016/j.freeradbiomed.2008.09.001 复制DOI
    作者列表:de Vries HE,Witte M,Hondius D,Rozemuller AJ,Drukarch B,Hoozemans J,van Horssen J
    BACKGROUND & AIMS: :Neurodegenerative diseases share various pathological features, such as accumulation of aberrant protein aggregates, microglial activation, and mitochondrial dysfunction. These pathological processes are associated with generation of reactive oxygen species (ROS), which cause oxidative stress and subsequent damage to essential molecules, such as lipids, proteins, and DNA. Hence, enhanced ROS production and oxidative injury play a cardinal role in the onset and progression of neurodegenerative disorders. To maintain a proper redox balance, the central nervous system is endowed with an antioxidant defense mechanism consisting of endogenous antioxidant enzymes. Expression of most antioxidant enzymes is tightly controlled by the antioxidant response element (ARE) and is activated by nuclear factor E2-related factor 2 (Nrf2). In past years reports have highlighted the protective effects of Nrf2 activation in reducing oxidative stress in both in vitro and in vivo models of neurodegenerative disorders. Here we provide an overview of the involvement of ROS-induced oxidative damage in Alzheimer's disease, Parkinson's disease, and Huntington's disease and we discuss the potential therapeutic effects of antioxidant enzymes and compounds that activate the Nrf2-ARE pathway.
    背景与目标: : 神经退行性疾病具有多种病理特征,例如异常蛋白聚集体的积累,小胶质细胞激活和线粒体功能障碍。这些病理过程与活性氧 (ROS) 的产生有关,活性氧 (ROS) 会导致氧化应激并随后对必需分子 (例如脂质,蛋白质和DNA) 造成损害。因此,增强的ROS产生和氧化损伤在神经退行性疾病的发生和发展中起主要作用。为了保持适当的氧化还原平衡,中枢神经系统具有由内源性抗氧化酶组成的抗氧化防御机制。大多数抗氧化酶的表达由抗氧化反应元件 (ARE) 严格控制,并由核因子E2-related因子2 (Nrf2) 激活。在过去的几年中,报告强调了Nrf2激活在减少神经退行性疾病的体外和体内模型中的氧化应激中的保护作用。在这里,我们概述了ROS诱导的氧化损伤在阿尔茨海默氏病,帕金森氏病和亨廷顿氏病中的作用,并讨论了激活Nrf2-ARE途径的抗氧化酶和化合物的潜在治疗作用。
  • 【尿素对镉诱导的Cabomba caroliniana的植物毒性的调节涉及光合代谢和抗氧化状态。】 复制标题 收藏 收藏
    DOI:10.1016/j.ecoenv.2017.06.003 复制DOI
    作者列表:Huang W,Shao H,Zhou S,Zhou Q,Li W,Xing W
    BACKGROUND & AIMS: :Urea is a widespread organic pollutant, which can be a nitrogen source, playing different roles in the growth of submerged macrophytes depending on concentrations, while high cadmium (Cd) concentrations are often toxic to macrophytes. In order to evaluate the combined effect of urea and Cd on a submerged macrophyte, Cabomba caroliniana, the morphological and physiological responses of C. caroliniana in the presence of urea and Cd were studied. The results showed that high concentrations of urea (400mgL-1) and Cd (500µmolL-1) had negative effects on C. caroliniana. There were strong visible symptoms of toxicity after 4 days of exposure under Cd-alone, 400mgL-1 urea, and Cd+400mgL-1 urea treatments. In addition, 400mgL-1 urea and Cd had adverse effects on C. caroliniana's pigment system. Significant losses in chlorophyll fluorescence and photosynthetic rates, as well as Rubisco activity were also observed under Cd-alone, 400mgL-1 urea, and Cd+400mgL-1 urea treatments. 400mgL-1 urea markedly enhanced Cd toxicity in C. caroliniana, reflected by a sharp decrease in photosynthetic activity and more visible toxicity symptoms. The results of thiobarbituric acid reactive substances (TBARS) pointed to extreme oxidative stress in C. caroliniana induced under Cd or 400mgL-1 urea exposure. Exogenous ascorbate (AsA) protected C. caroliniana from adverse damage in 400mgL-1 urea, which further corroborated the oxidative stress claim under 400mgL-1 urea. However, results also demonstrated that lower urea concentration (10mgL-1) alleviated Cd-induced phytotoxicity by stimulating chlorophyll synthesis and photosynthetic activity, as well as activating the activity of catalase (CAT) and glutathione-S-transferase (GST), which may explain the alleviating effect of urea on C. caroliniana under Cd stress.
    背景与目标: : 尿素是一种广泛存在的有机污染物,可能是氮源,根据浓度的不同,在淹没的大型植物的生长中起不同的作用,而高浓度的镉 (Cd) 通常对大型植物有毒。为了评估尿素和Cd对淹没的大型植物Cabomba caroliniana的综合作用,研究了在尿素和Cd存在下caroliniana的形态和生理响应。结果表明,高浓度的尿素 (400mgL-1) 和Cd (500µmolL-1) 对C. caroliniana有负面影响。在单独的Cd,400mgL-1尿素和Cd 400mgL-1尿素处理下暴露4天后,出现了强烈的可见毒性症状。此外,400mgL-1尿素和Cd对C. caroliniana的色素系统也有不利影响。在单独的Cd,400mgL-1尿素和Cd 400mgL-1尿素处理下,还观察到叶绿素荧光和光合速率以及Rubisco活性的显着损失。400mgL-1尿素显着增强了C. caroliniana的Cd毒性,这反映在光合作用活性急剧下降和更明显的毒性症状上。硫代巴比妥酸反应性物质 (TBARS) 的结果表明,在Cd或400mgL-1尿素暴露下,caroliniana会引起极端的氧化应激。外源性抗坏血酸 (AsA) 保护了caroliniana免受400mgL-1尿素的不利损害,这进一步证实了400mgL-1尿素下的氧化应激要求。然而,结果还表明,较低的尿素浓度 (10mgL-1) 通过刺激叶绿素合成和光合活性以及激活过氧化氢酶 (CAT) 和谷胱甘肽S-转移酶 (GST) 的活性来减轻Cd诱导的植物毒性,这可以解释尿素在Cd胁迫下对C. caroliniana的缓解作用。
  • 【Mucuna不同种质的膳食抗氧化活性。】 复制标题 收藏 收藏
    DOI:10.1089/jmf.2012.2697 复制DOI
    作者列表:Uma S,Gurumoorthi P
    BACKGROUND & AIMS: :Mucuna pruriens, an underutilized native legume of South India has been reported to have high levels of L-Dopa, and used in the treatment of Parkinson's disease. Cellular damage arising from reactive oxygen and nitrogen species is said to cause neurodegenerative disorders. Antioxidants could assuage this oxidative damage of tissue directly and/or indirectly by enhancing natural defenses and also scavenging the free radicals. In this context, the antioxidative potential of different germplasm of Mucuna species was analyzed. Assays were performed to evaluate the enzymatic and nonenzymatic antioxidants in the extracts. Methanolic extracts of Mucuna (black germplasm) yielded high levels dietary antioxidants viz., flavonoids, alkaloids, saponins, steroids and phlobotannins qualitatively. Tannins, total phenols, flavanoids, and steroids accounted for 13.60±1.8 tannic acid equivalents, 58.47±3.19 gallic acid equivalents, 23.7±3.12 quercetin equivalents, and 20.3±1.0 mg per 100 mg β-sitosterol equivalents, respectively. Percentage of scavenging activity against hydroxyl, superoxide anion, nitric oxide, and hydrogen peroxide radicals were 39.12%; 57.1%; 41.26%, and 25.68%, respectively. Reducing capacity (17.74%) was seen to concurrently increase with extract concentration. Catalase, glutathione reductase, and polyphenol oxidase activities were found to be 30.15; 26.6 and 42.5 μmol/mg of protein, respectively. The methanolic extract yielded the most potent levels of dietary antioxidants and exhibited high free-radical-scavenging activity.
    背景与目标: : Mucuna pruriens是印度南部未充分利用的本地豆类,据报道其L-多巴含量很高,可用于治疗帕金森氏病。活性氧和氮引起的细胞损伤据说会导致神经退行性疾病。抗氧化剂可以通过增强自然防御能力并清除自由基来直接和/或间接缓解组织的这种氧化损伤。在这种情况下,分析了Mucuna物种不同种质的抗氧化潜力。进行测定以评估提取物中的酶和非酶抗氧化剂。Mucuna (黑色种质) 的甲醇提取物定性地产生了高水平的饮食抗氧化剂,即类黄酮,生物碱,皂苷,类固醇和phlobotanins。单宁,总酚,类黄酮和类固醇分别占13.60 ± 1.8鞣酸当量,58.47 ± 3.19没食子酸当量,23.7 ± 3.12槲皮素当量和20.3 ± 1.0 mg/100 mg β-谷甾醇当量。对羟基、超氧阴离子、一氧化氮和过氧化氢自由基的清除活性百分比分别39.12%; 57.1%; 41.26% 和25.68%。可见还原能力 (17.74%) 随着提取物浓度的增加而同时增加。发现过氧化氢酶,谷胱甘肽还原酶和多酚氧化酶活性30.15; 分别为26.6和42.5 μ mol/mg蛋白质。甲醇提取物可产生最有效的膳食抗氧化剂,并具有很高的自由基清除活性。
  • 【自蚀刻粘合剂与正常和涂片层脱蛋白牙本质的粘合耐久性: 还原剂和植物提取物抗氧化剂的作用。】 复制标题 收藏 收藏
    DOI:10.3290/j.jad.a38409 复制DOI
    作者列表:Prasansuttiporn T,Thanatvarakorn O,Tagami J,Foxton RM,Nakajima M
    BACKGROUND & AIMS: PURPOSE:To evaluate the effect of a reducing agent and plant-extract antioxidant on the bonding durability of a self-etch adhesive to normal and NaOCl-treated, smear-layer-deproteinized dentin. MATERIALS AND METHODS:Flat smear-layer-covered dentin surfaces from 60 extracted human molars were prepared by removing the occlusal enamel. The teeth were divided into two groups with or without NaOCl-deproteinizing treatment for 30 s, and further divided into three subgroups as follows: no application of antioxidant, application of Accel (p-toluenesulfinic acid sodium salt solution) for 5 s, or application of rosmarinic acid solution for 5 s. All treated dentin surfaces were bonded with a two-step self-etch adhesive (Clearfil SE Bond) and restored with composite (Clearfil AP-X). The bonded teeth were sectioned into a hourglass-shaped sticks with a composite-dentin bonded interface area of 1.0 mm2. After storage in artificial saliva for 24 h or 1 year, the specimens were subjected to the microtensile bond strength test (n = 15). Data were statistically analyzed with three-way ANOVA, Tukey's post-hoc test, and the t-test (p < 0.05). RESULTS:Without an antioxidant, 1-year storage significantly reduced the bond strengths of the self-etch adhesive to normal and smear-layer-deproteinized dentin compared with those after 24-h storage (p < 0.05). Application of Accel and rosmarinic acid restored the compromised initial bond strengths to smear-layer-deproteinized dentin (p < 0.05), and prevented long-term deterioration of bond strengths to both normal and smear-layer-deproteinized dentin (p > 0.05). CONCLUSION:Application of Accel and rosmarinic acid improved bonding durability of the self-etch adhesive to both normal and smear-layer-deproteinized dentin.
    背景与目标:
  • 【实验性革兰氏阴性脓毒症期间大鼠的氧化DNA损伤和总抗氧化状态。】 复制标题 收藏 收藏
    DOI:10.1177/0960327108088972 复制DOI
    作者列表:Kaymak C,Kadioglu E,Ozcagli E,Osmanoglu G,Izdes S,Agalar C,Basar H,Sardas S
    BACKGROUND & AIMS: :Sepsis and septic shock remains as leading cause of death in adult intensive care units. It is widely accepted that gram-negative bacteria and their endotoxins cause sepsis and septic shock, predominantly. Enhanced generation of reactive oxygen species may be responsible for tissue injury in septic shock and endotoxemia. The aim of this study was to assess oxidative DNA damage and the total antioxidant status (TAS) in peripheral lymphocytes of rats during different intraperitoneal gram-negative sepsis stages. Adult male Sprague-Dawley rats were divided randomly into four groups. Control group was intraperitoneally inoculated with 2 mL of pyrogene-free saline (Group I, n = 6), and the other rats received an intraperitoneal inoculum with 2 mL of saline containing 2 x 10(8) CFU of Escherichia coli. The animals were killed at time zero (Group I, n = 6), at 6th (Group II, n = 7), 12th (Group III, n = 7), and 24th (Group IV, n = 7) hour after the E. coli inoculation. Oxidative DNA damage in peripheral lymphocytes of rats was evaluated by modified comet assay (single-cell gel electrophoresis). Formamidopyrimidine DNA glycosylase (Fpg) and Endonuclease III (Endo III) were used to detect oxidized purines and pyrimidines, respectively. Total antioxidant quantification was carried out using ABTS+ (2,2'-Azino-di-[3 ethylbenzthiazoline sulphonate]) radical formation kinetics (Randox kit) in serum samples. Significant elevations of basal levels of strand breaks (SB) in Group IV were observed as compared with Group I, II, and III. There was a significant increase in Fpg sites in Group III as compared with Group I and II. However, there was no significant difference in terms of Endo III sites in any of the groups. Although the TAS was decreased with the stages of sepsis, this moderate decrease was significant in only Group IV as compared with Group I. There was no statistically significant correlation between DNA damage and TAS for any of the groups.
    背景与目标: : 脓毒症和脓毒休克仍然是成人重症监护病房死亡的主要原因。人们普遍认为,革兰氏阴性菌及其内毒素主要引起败血症和败血性休克。活性氧的产生增加可能是败血性休克和内毒素血症中组织损伤的原因。这项研究的目的是评估不同腹膜内革兰氏阴性脓毒症阶段大鼠外周淋巴细胞的氧化DNA损伤和总抗氧化状态 (TAS)。成年雄性Sprague-Dawley大鼠随机分为四组。对照组腹腔接种2毫升不含焦原的生理盐水 (I组,n = 6),其余大鼠腹腔接种2毫升含大肠杆菌2 × 10(8) CFU的生理盐水。在接种大肠杆菌后第6小时 (第I组,n = 6) 、第12小时 (第III组,n = 7) 、第12小时 (第III组,n = 7) 和第24小时 (第IV组,n = 7) 处死动物。通过改良的彗星试验 (单细胞凝胶电泳) 评估大鼠外周淋巴细胞的氧化DNA损伤。甲酰胺嘧啶DNA糖基化酶 (Fpg) 和核酸内切酶III (Endo III) 分别用于检测氧化的嘌呤和嘧啶。使用血清样品中的ABTS + (2,2 '-叠氮基-二-[3乙基苯并噻唑啉磺酸盐]) 自由基形成动力学 (randoxkit) 进行总抗氧化剂定量。与I,II和III组相比,IV组中链断裂 (SB) 的基础水平显着升高。与I组和II组相比,III组的Fpg位点显着增加。但是,在任何一组中,Endo III位点均无显着差异。尽管TAS随着脓毒症的阶段而降低,但与I组相比,仅IV组的这种中度降低是显着的。在任何组中,DNA损伤与TAS之间都没有统计学上的显着相关性。
  • 【机械因素调节了mdx肌肉对偏心强度损失的敏感性及其通过抗氧化剂和钙调节剂的保护。】 复制标题 收藏 收藏
    DOI:10.1186/s13395-020-0221-2 复制DOI
    作者列表:Lindsay A,Baumann CW,Rebbeck RT,Yuen SL,Southern WM,Hodges JS,Cornea RL,Thomas DD,Ervasti JM,Lowe DA
    BACKGROUND & AIMS: BACKGROUND:Dystrophin deficiency sensitizes skeletal muscle of mice to eccentric contraction (ECC)-induced strength loss. ECC protocols distinguish dystrophin-deficient from healthy, wild type muscle, and test the efficacy of therapeutics for Duchenne muscular dystrophy (DMD). However, given the large lab-to-lab variability in ECC-induced strength loss of dystrophin-deficient mouse skeletal muscle (10-95%), mechanical factors of the contraction likely impact the degree of loss. Therefore, the purpose of this study was to evaluate the extent to which mechanical variables impact sensitivity of dystrophin-deficient mouse skeletal muscle to ECC. METHODS:We completed ex vivo and in vivo muscle preparations of the dystrophin-deficient mdx mouse and designed ECC protocols within physiological ranges of contractile parameters (length change, velocity, contraction duration, and stimulation frequencies). To determine whether these contractile parameters affected known factors associated with ECC-induced strength loss, we measured sarcolemmal damage after ECC as well as strength loss in the presence of the antioxidant N-acetylcysteine (NAC) and small molecule calcium modulators that increase SERCA activity (DS-11966966 and CDN1163) or lower calcium leak from the ryanodine receptor (Chloroxine and Myricetin). RESULTS:The magnitude of length change, work, and stimulation duration ex vivo and in vivo of an ECC were the most important determinants of strength loss in mdx muscle. Passive lengthening and submaximal stimulations did not induce strength loss. We further showed that sarcolemmal permeability was associated with muscle length change, but it only accounted for a minimal fraction (21%) of the total strength loss (70%). The magnitude of length change also significantly influenced the degree to which NAC and small molecule calcium modulators protected against ECC-induced strength loss. CONCLUSIONS:These results indicate that ECC-induced strength loss of mdx skeletal muscle is dependent on the mechanical properties of the contraction and that mdx muscle is insensitive to ECC at submaximal stimulation frequencies. Rigorous design of ECC protocols is critical for effective use of strength loss as a readout in evaluating potential therapeutics for muscular dystrophy.
    背景与目标:
  • 【巴马汀抗氧化和抗乙酰胆碱酯酶活性: 临床前评估。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Chaves SKM,Afzal MI,Islam MT,Hameed A,Da Mata AMOF,Da Silva Araújo L,Ali SW,Rolim HML,De Medeiros MDGF,Costa EV,Salehi B,Martins N,Arif AM,Imran M,Sharifi-Rad J,Melo-Cavalcante AAC,Feitosa CM
    BACKGROUND & AIMS: :There is evidence that palmatine (PA), an alkaloid isolated from the Guatteria friesiana plant, has some important biological activities, including anti-inflammatory and antidepressant effects. In this study, the antioxidant and anti-acetylcholinesterase (AChE) effects of PA were assessed. The antioxidant capacity was evaluated in vitro and in vivo through 7 distinct assays, and the anti-AChE activity was determined in vitro. The standards, trolox and ascorbic acid were used for the in vitro antioxidant test, while hydrogen peroxide was selected as a stressor for the Saccharomyces cerevisiae test. Additionally, PA was also combined with trolox and ascorbic acid to determine the likelihood of synergistic effects occurrence to what concerns to antioxidant potential. PA exhibited a potent and concentration-dependent antioxidant potential, although a stronger antioxidant activity was stated using the PA + trolox combination. PA was also found to inhibit AChE activity when compared to the negative control. Thus, PA may be viewed as a promissory phytotherapeutic agent to manage oxidative stress-mediated neurological diseases, especially the Alzheimer's and Parkinson's diseases.
    背景与目标: : 有证据表明,从Guatteria friesiana植物中分离出的生物碱palmatine (PA) 具有一些重要的生物学活性,包括抗炎和抗抑郁作用。在这项研究中,评估了PA的抗氧化剂和抗乙酰胆碱酯酶 (AChE) 的作用。通过7种不同的试验在体外和体内评估抗氧化能力,并在体外确定抗AChE活性。标准,trolox和抗坏血酸用于体外抗氧化测试,而过氧化氢被选为酿酒酵母测试的应激源。此外,PA还与trolox和抗坏血酸结合使用,以确定与抗氧化潜力有关的协同效应发生的可能性。尽管使用PA trolox组合表明了更强的抗氧化活性,但PA表现出有效且依赖浓度的抗氧化潜力。与阴性对照相比,PA还可抑制AChE活性。因此,PA可以被视为治疗氧化应激介导的神经系统疾病 (尤其是阿尔茨海默氏病和帕金森氏病) 的一种潜在的植物治疗剂。
  • 【由极端耐辐射的细菌Deinococcus radiodurans产生的胞外多糖 (DeinoPol) 的抗氧化活性。】 复制标题 收藏 收藏
    DOI:10.1038/s41598-019-56141-3 复制DOI
    作者列表:Lin SM,Baek CY,Jung JH,Kim WS,Song HY,Lee JH,Ji HJ,Zhi Y,Kang BS,Bahn YS,Seo HS,Lim S
    BACKGROUND & AIMS: :Deinococcus radiodurans shows extreme resistance to a range of remarkable environmental stresses. Deinococcal exopolysaccharide (DeinoPol) is a component of the cell wall, but its role in stress resistance has not yet been well-described. In this study, we isolated and characterized DeinoPol from Deinococcus radiodurans R1 strain and investigated its application as an antioxidant agent. Bioinformatic analysis indicated that dra0033, encoding an ExoP-like protein, was involved in DeinoPol biosynthesis, and dra0033 mutation significantly decreased survival rates in response to stresses. Purified DeinoPol consists of different monosaccharides and has a molecular weight of approximately 80 to 100 kDa. DeinoPol also demonstrates highly protective effects on human keratinocytes in response to stress-induced apoptosis by effectively scavenging ROS. Taken together, these findings indicate that DeinoPol is the first reported deinococcal exopolysaccharide that might be used in cosmetics and pharmaceuticals as a safe and attractive radical scavenger.
    背景与目标: : 放射性球菌对一系列显着的环境压力表现出极大的抵抗力。Deinococcal胞外多糖 (DeinoPol) 是细胞壁的组成部分,但其在抗逆性中的作用尚未得到很好的描述。在这项研究中,我们从放射性球菌R1菌株中分离并鉴定了去诺波尔,并研究了其作为抗氧化剂的应用。生物信息学分析表明,编码ExoP样蛋白的dra0033参与了DeinoPol的生物合成,dra0033突变显着降低了响应压力的存活率。纯化的DeinoPol由不同的单糖组成,分子量约为80至100  kDa。DeinoPol还通过有效清除ROS对人的角质形成细胞具有高度的保护作用,可响应应激诱导的细胞凋亡。总之,这些发现表明,DeinoPol是第一个报道的deinococcal胞外多糖,可能用于化妆品和药品中作为安全和有吸引力的自由基清除剂。
  • 【香菜提取物和组分的抗氧化活性。】 复制标题 收藏 收藏
    DOI:10.1016/j.biortech.2008.07.021 复制DOI
    作者列表:Li HY,Hao ZB,Wang XL,Huang L,Li JP
    BACKGROUND & AIMS: :The antioxidant activities of water extract, methanol extract, ethyl acetate, and n-BuOH fractions of methanol extract from Lysimachia foenum-graecum Hance were investigated in this study. Various methods, such as the total antioxidant capacity measured by phosphomolybdenum method, scavenging activities towards 1,1-diphenyl-2-picryhydrazyl (DPPH) radical, superoxide anion radical, and hydroxyl radical, were established in in vitro systems. The amounts of total phenolics and total flavonoids in the extracts and fractions were also determined by spectrophotometric methods. The results showed that all the extracts and fractions exhibited antioxidant and radical-scavenging activities at different magnitudes of potency. The decreasing order of antioxidant and radical-scavenging activities among the extracts assayed through all the four methods were found to be ethyl acetate fraction>n-BuOH fraction>methanol extract>water extract. This similar order of the amounts of total phenolics and total flavonoids shows that the extent of antioxidant and radical-scavenging activities is in accordance with the amounts of phenolics and flavonoids present in extracts and fractions. The extracts of L. foenum-graecum Hance might be valuable antioxidant natural sources and seemed to be applicable in both healthy medicine and food industry.
    背景与目标: : 在这项研究中,研究了水提取物,甲醇提取物,乙酸乙酯和甲醇提取物的n-BuOH馏分的抗氧化活性。在体外系统中建立了各种方法,例如通过磷钼法测量的总抗氧化能力,对1,1-二苯基-2-微肼基 (DPPH) 自由基,超氧阴离子自由基和羟基自由基的清除活性。还通过分光光度法测定了提取物和馏分中总酚和总黄酮的含量。结果表明,所有提取物和级分在不同的效价下均表现出抗氧化和自由基清除活性。通过所有四种方法测定的提取物中抗氧化剂和自由基清除活性的递减顺序为乙酸乙酯分数> n-BuOH分数> 甲醇提取物> 水提取物。总酚和总黄酮的量的这种相似顺序表明,抗氧化和自由基清除活性的程度与提取物和组分中存在的酚类和类黄酮的量一致。L. foenum-graecum Hance的提取物可能是有价值的抗氧化剂天然来源,并且似乎适用于健康医学和食品工业。

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