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Effects of enzymatic and non-enzymatic antioxidants in diluents on cryopreserved bull epididymal sperm
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作者 Hasan Sakhdary Abbas Farshad +2 位作者 Jalal Rostamzadeh Fateme Bahri Binabaj Keyvan Sobhani 《Asian pacific Journal of Reproduction》 2022年第1期44-50,共7页
Objective:To evaluate the supplementation effects of vitamin E,vitamin C,superoxide dismutase(SOD),and catalase to diluents on bull cryopreserved epididymal sperm.Methods:Sperm were retrieved from 20 bull testes and w... Objective:To evaluate the supplementation effects of vitamin E,vitamin C,superoxide dismutase(SOD),and catalase to diluents on bull cryopreserved epididymal sperm.Methods:Sperm were retrieved from 20 bull testes and were then supplemented with 0.1 mM vitamin E,5.0 mM vitamin C,100.0 IU/mL SOD,and 100.0μg/mL catalase alone,or in a combination.The control treatment contained no addition.After supplementation,samples were frozen and stored in liquid nitrogen.The sperm parameters including motility,progressive motility,viability,acrosome integrity,plasma membrane integrity,kinematics and DNA damage were evaluated following the thawing process.Results:Vitamin E alone significantly increased the parameters of acrosome and membrane integrity compared to the control treatment(P<0.05).While compared to the control treatment,vitamin C had no improvement effect on sperm characteristics except for membrane integrity.Treatment of vitamin E+vitamin C had a significant improvement in total motility,progressive motility,viability,membrane and acrosome integrity compared to the control and other treatments(P<0.05).Compared to the control treatment,addition of SOD or catalase alone significantly improved the percentages of total motility,progressive motility,viability,membrane and acrosome integrity(P<0.05).Furthermore,SOD+catalase significantly increased total motility,progressive motility,viability,acrosome and membrane integrity characteristics compared to the catalase treatment(P<0.05).Vitamin E alone,vitamin E+vitamin C,and SOD in diluents decreased DNA damages and thereby improved the rate of intact sperm heads.Conclusions:Addition of 100.0 IU/mL SOD alone and 0.1 mM vitamin E+5.0 mM vitamin C,and also 5.0 mM vitamin C+100μg/mL catalase in a combination improves the quality of cryopreserved bull epididymal sperm and could be used for cryopreservation. 展开更多
关键词 antioxidant CRYOPRESERVATION Spermatological characteristics DNA damage BULL Vitamin E Vitamin C Superoxide dismutase CATALASE Oxidative stress
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Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants 被引量:1
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作者 Su Shuo Long Jun +2 位作者 Duan Qinghua Zhou Han Zhao Yi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期135-145,共11页
To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular me... To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular simulations.Calculation results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen peroxide.Based on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur atoms.Experimental results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions. 展开更多
关键词 lubricating oil antioxidANT molecular mechanism molecular design antioxidant performance
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Response of enzymatic and non-enzymatic antioxidant defense systems of Polygonum hydropiper to Mn stress 被引量:2
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作者 杨贤均 邓冬梅 +1 位作者 刘可慧 于方明 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第4期793-797,共5页
The response of enzyme and non-enzymatic antioxidants of Mn hyperaccumuator, Polygonum hydropiper (P. hydropiper), to Mn stress was studied using hydroponics culture experiments to explore the mechanism of Mn tolera... The response of enzyme and non-enzymatic antioxidants of Mn hyperaccumuator, Polygonum hydropiper (P. hydropiper), to Mn stress was studied using hydroponics culture experiments to explore the mechanism of Mn tolerance in this species. Results showed that both chlorophyll and carotenoid contents significantly (p〈0.05) decreased with increasing Mn treatment levels (0, 0.5, 1, 2, 4, and 8 mg/L) in hydroponics. The concentrations of malondialdehyde (MDA) and hydrogen peroxide (H202) in the root and shoot of P hydropiper were accumulated under Mn stress. Meanwhile, the anti-oxidative functions of several important enzymes, including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) in plants were stimulated by Mn spike in leaves and roots, especially at low Mn stress; while sulfhydryl group (--SH) and glutathion (GSH) were likely involved in Mn detoxification ofP. hydropiper under high Mn stress. 展开更多
关键词 Polygonum hydropiper HYPERACCUMULATION enzymatic antioxidative defense non-enzymatic antioxidative defense
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Effect of antioxidants on the efficiency of jet milling and the powder characteristics of Sm2Co17 permanent magnets
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作者 Da-Shuai Xu Lei Liu +6 位作者 Jian-Hui Yuan Bo Zhou Chuang-Hui Dong Feng-Qing Wang Yong Ding Ying-Li Sun A-Ru Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期615-620,共6页
This study investigated the effect of antioxidants on the grinding efficiency,magnetic powder characteristics,microstructure,and magnetic properties of 2:17 type SmCo permanent magnet materials.The results show that a... This study investigated the effect of antioxidants on the grinding efficiency,magnetic powder characteristics,microstructure,and magnetic properties of 2:17 type SmCo permanent magnet materials.The results show that adding antioxidants helps improve the dispersion among magnetic powders,leading to a 33.3%decrease in jet milling time and a 15.8%increase in magnet powder production yield.Additionally,adding antioxidants enhances the oxidation resistance of the magnetic powders.After being stored in a constant temperature air environment at 25C for 48 h,the O content in the powder decreased by 33%compared to samples without antioxidants.While in the magnet body,the O content decreased from 0.21 wt.%to 0.14 wt.%,which helps increase the effective Sm content and domain wall pinning uniformity in the magnet.Excellent magnetic properties were obtained in the magnet with added antioxidants:B_(r)=11.6 kGs,SF=79.6%,H_(cj)=16.8 kOe,and(BH)_(max)=32.5 MGOe. 展开更多
关键词 antioxidANT SmCo permanent magnet oxidation resistance grinding efficiency
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Distribution of antioxidants and phenolic compounds in flour milling fractions from hard red winter wheat
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作者 Lauren Renee Brewer Jittawan Kubola +1 位作者 Sirithon Siriamornpun Yong-Cheng Shi 《Grain & Oil Science and Technology》 CAS 2024年第2期71-78,共8页
Mature wheat kernels contain three main parts:endosperm,bran,and germ.Flour milling results in multiple streams that are chemically different;however,the distribution of antioxidants and phenolic compounds has not bee... Mature wheat kernels contain three main parts:endosperm,bran,and germ.Flour milling results in multiple streams that are chemically different;however,the distribution of antioxidants and phenolic compounds has not been well documented in terms of conventional milling by-product streams.In this study,multiple analytical methods were used to investigate antioxidant activity and phenolic compound compositions of hard red winter wheat(whole ground wheat),the parts of a wheat kernel(bran,flour,germ),and wheat by-product streams(mill feed,red dog,shorts)for the first time.For each mill stream,phenolic compounds(total,flavonoid,and anthocyanin contents)were determined and antioxidant activities were evaluated with 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical-scavenging activity,ferric reducing/antioxidant power(FRAP),and total antioxidant capacity assays.Significant differences(P<0.05)were observed in phenolic concentrations among fractions of bran,flour,and germ milled from the same kernels and noted that germ accounts for the majority of antioxidant properties,whereas bran contains a substantial portion of phenolic compounds and anthocyanins.Mill feed was high in phenolic content(5.29 mg FAE/g),total antioxidant capacity(866 mg/g),and antioxidant activity(up to 75% DPPH inhibition and 20.26μmol FeSO_(4)/g).The comprehensive information on distribution of antioxidants and phenolic compounds provides insights for future human consumption of commonly produced co-products from flour milling,and for selecting and using different milling fractions to make foods with improved nutritional properties. 展开更多
关键词 Wheat Milling streams antioxidants Phenolic acids Flavonoid ANTHOCYANIN
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Lead induced overactivation of phagocytes and variation in enzymatic and non-enzymatic antioxidant defenses in intestinal macrophages of <i>Channa punctatus</i> 被引量:1
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作者 Nilantika Paul Mahuya Sengupta 《Modern Research in Inflammation》 2013年第2期28-35,共8页
The aim of this study is to assess the adverse effects of lead, a well-documented non-essential element that occurs naturally in the environment, on Channa punctatus, in relation with ROS production and oxidative stre... The aim of this study is to assess the adverse effects of lead, a well-documented non-essential element that occurs naturally in the environment, on Channa punctatus, in relation with ROS production and oxidative stress. Fishes were sampled, acclimatized and kept treated or untreated with lead (9.43 mg/L) under observation for 4 days. At day 4, respiratory burst activity, lipid peroxidation activity and superoxide dismutase level increased significantly in treated group as compared to the control. On the contrary, catalase, glutathione S-transferase, glutathione peroxidase, glutathione reductase and reduced glutathione activity decreased on treatment with lead. These results suggest that heavy metal like lead induces oxidative stress, influences the antioxidant defense system and may lead to physiological disorders rendering the health and survival of exposed fish to a compromised state. 展开更多
关键词 LEAD Channa PUNCTATUS antioxidant Oxidative Stress Lipid Peroxidation Respiratory Burst Glutathione Bioaccumulation
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Non-enzymatic methods for isolation of stromal vascular fraction and adipose-derived stem cells:A systematic review
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作者 Vamsi Krishna Mundluru MJ Naidu +4 位作者 Ravi Teja Mundluru Naveen Jeyaraman Sathish Muthu Swaminathan Ramasubramanian Madhan Jeyaraman 《World Journal of Methodology》 2024年第2期134-144,共11页
BACKGROUND Adipose-derived stem cells(ADSCs)and the stromal vascular fraction(SVF)have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions.Traditional enzy... BACKGROUND Adipose-derived stem cells(ADSCs)and the stromal vascular fraction(SVF)have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions.Traditional enzymatic methods for isolating these cells face challenges such as high costs,lengthy processing time,and regulatory complexities.AIM This systematic review aimed to assess the efficacy and practicality of nonenzymatic,mechanical methods for isolating SVF and ADSCs,comparing these to conventional enzymatic approaches.METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,a comprehensive literature search was conducted across multiple databases.Studies were selected based on inclusion criteria focused on non-enzymatic isolation methods for SVF and ADSCs from adipose tissue.The risk of bias was assessed,and a qualitative synthesis of findings was performed due to the methodological heterogeneity of the included studies.RESULTS Nineteen studies met the inclusion criteria,highlighting various mechanical techniques such as centrifugation,vortexing,and ultrasonic cavitation.The review identified significant variability in cell yield and viability,and the integrity of isolated cells across different non-enzymatic methods compared to enzymatic procedures.Despite some advantages of mechanical methods,including reduced processing time and avoidance of enzymatic reagents,the evidence suggests a need for optimization to match the cell quality and therapeutic efficacy achievable with enzymatic isolation.CONCLUSION Non-enzymatic,mechanical methods offer a promising alternative to enzymatic isolation of SVF and ADSCs,potentially simplifying the isolation process and reducing regulatory hurdles.However,further research is necessary to standardize these techniques and ensure consistent,high-quality cell yields for clinical applications.The development of efficient,safe,and reproducible non-enzymatic isolation methods could significantly advance the field of regenerative medicine. 展开更多
关键词 Adipose-derived stem cells Stromal vascular fraction Regenerative medicine non-enzymatic isolation Mechanical separation techniques
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Physicochemical,rheological and antioxidant profiling of yogurt prepared from non-enzymatically and enzymatically hydrolyzed potato powder under refrigeration 被引量:1
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作者 Ishtiaq Ahmad Zhouyi Xiong +7 位作者 Hanguo Xiong Rana Muhammad Aadil Nauman Khalid Allah Bakash Jvaid Lakhoo Zia-ud-din Asad Nawaz Noman Walayat Rao Sanaullah Khan 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期69-78,共10页
Evidences show that the storage period greatly affects the quality of yogurt.In this study,three types of yogurt:control yogurt(CY),non-hydrolyzed potato powder yogurt(PPY)and enzymatically hydrolyzed potato powder yo... Evidences show that the storage period greatly affects the quality of yogurt.In this study,three types of yogurt:control yogurt(CY),non-hydrolyzed potato powder yogurt(PPY)and enzymatically hydrolyzed potato powder yogurt(EHPPY)were prepared at 42℃ for 5 h and stored for 28 days at 4℃.The yogurts were evaluated for quality characteristics at different storage periods.Negligible differences in pH values,titratable acidities and viable counts were detected in all three types of yogurt during storage.However,compared to other yogurts,EHPPY exhibited desirable water holding capacity,throughout the storage period.Apart from this,sensory properties and antioxidant activities(2-diphenyl-1-picryl-hydrazyl(DPPH)free radical scavenging activity and ferric reducing antioxidant power(FRAP))of EHPPY were also significantly improved during the storage period.Furthermore,the storage(G’)and loss(G”)modulus of PPY,EHPPY were lower than CY at 4℃ while a hysteresis loop was shown by all yogurts at the temperature range of 4-50℃ indicating higher G’(elasticity)than G”(viscosity).Based on our findings,EHPP could be an important functional ingredient in improving the quality and storage stability of yogurt for its production at an industrial level. 展开更多
关键词 Storage stability Potato powder YOGURT Rheology MICROBIOLOGY antioxidant activity
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The Non-Enzymatic Antioxidant and Level of Oxidative Stress of Tuberculosis Patients in Selected Treatment Center in Addis Ababa Ethiopia
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作者 Gebrehiwot Gebretsadik Daniel Seifu +1 位作者 Getnet Yimer M. K. C. Menon 《Journal of Tuberculosis Research》 2015年第3期63-71,共9页
Introduction: Non-enzymatic antioxidants are good scavengers of free radicals preventing their overproduction there by reducing the level of oxidative stress. This work was undertaken at Saint Peter TB specialized hos... Introduction: Non-enzymatic antioxidants are good scavengers of free radicals preventing their overproduction there by reducing the level of oxidative stress. This work was undertaken at Saint Peter TB specialized hospital and TekleHaimanot health center from March 2012 to May 2013.Aim: To determine changes in Non-Enzymatic Antioxidants and level of oxidative stress of tuberculosis Patients before and after taking anti tuberculosis treatment.Materials and Methods: In this comparative cross sectional study, a total of 210 individuals including: newly diagnosed TB patients as group-I (n = 70), TB patients who completed treatment as group-II (n = 70), and healthy volunteers as group-III (n = 70) were enrolled. Different methods were used to determine the parameters;vit-C (HPLC method), lipid peroxidation (thiobarbuituric acid method), and bilirubin (Colorimetric assay). Results: Vitamin-C (Vit-C) and of group-I showed a significant reduction (p < 0.001) as compared with both group-II and group-III whereas Malondialdehyde (MDA) level was increased. However, the total and direct bilirubin was not different among the groups. In group-III, there was a positive correlation between BMI and serum Vit-C (r = -0.305, p = 0.010). Vit-C showed a negative correlation with serum MDA in all the groups with values (r = -0.265, p = 0.027), (r = -0.389, p = 0.001) and (r = -0.375, p = 0.001) for group-I, group-II and group-III respectively. In addition to this Vit-C was negatively correlated with serum UA (r = -0.285, p = 0.017) in group-I. Conclusion: The findings of the current study suggest that the amount of Vit-C in the newly diagnosed TB patients and those who finished their treatment is much lower than the healthy volunteers. In contrast to this, the MDA value was significantly higher both in the newly diagnosed TB patients and TB patients who completed treatment than in healthy volunteers suggesting higher degree of oxidative stress. 展开更多
关键词 TUBERCULOSIS non-enzymatic antioxidants OXIDATIVE Stress
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Antioxidant and lipoxygenase inhibitory properties of a novel flavonoid from Pistacia chinensis Bunge and its molecular docking analysis
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作者 Abdur Rauf Zuneera Akram +6 位作者 Naveed Muhammad Najla AlMasoud Taghrid Saad Alomar Saima Naz Abdul Wadood Chandni Hayat Marcello Iriti 《Traditional Medicine Research》 2025年第2期30-36,共7页
Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and ... Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and anti-lipoxygenase(LOX)properties of the isolated compound 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-one from Pistacia chinensis.Methods:LOX assay and antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl(DPPH)assay were performed.Molecular docking studies were conducted using a molecular operating environment.Results:The LOX assay revealed significant inhibitory effects at 0.2µM concentration,with an IC50 value of 37.80µM.The antioxidant effect demonstrated dose-dependency across 5 to 100µg/mL concentrations,reaching 93.09%at 100µg/mL,comparable to ascorbic acid’s 95.43%effect.Molecular docking studies highlighted strong interactions with the lipoxygenase enzyme,presenting an excellent docking score of-10.98 kcal/mol.Conclusion:These findings provide valuable insights into Pistacia chinensis’chemical components and biological effects,reinforcing its traditional medicinal applications. 展开更多
关键词 Pistacia chinensis Bunge antioxidANT DPPH assay antilipoxygenase docking analysis
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Exogenous melatonin enhances heat stress tolerance in sweetpotato by modulating antioxidant defense system,osmotic homeostasis and stomatal traits
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作者 Sunjeet Kumar Rui Yu +5 位作者 Yang Liu Yi Liu Mohammad Nauman Khan Yonghua Liu Mengzhao Wang Guopeng Zhu 《Horticultural Plant Journal》 2025年第1期431-445,共15页
Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairme... Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairments is essential for the long-term production of sweetpotatoes.Melatonin has been recognised for its capacity to assist plants in dealing with abiotic stress conditions.This research aimed to investigate how different doses of exogenous melatonin influence heat damage in sweetpotato plants.Heat stress drastically affected shoot and root fresh weight by 31.8 and 44.5%,respectively.This reduction resulted in oxidative stress characterised by increased formation of hydrogen peroxide(H_(2)O_(2))by 804.4%,superoxide ion(O_(2)^(·-))by 211.5%and malondialdehyde(MDA)by 234.2%.Heat stress also reduced chlorophyll concentration,photosystemⅡefficiency(F_v/F_m)by 15.3%and gaseous exchange.However,pre-treatment with 100μmol L^(-1)melatonin increased growth and reduced oxidative damage to sweetpotato plants under heat stress.In particular,melatonin decreased H_(2)O_(2),O_(2)^(·-)and MDA by 64.8%,42.7%and 38.2%,respectively.Melatonin also mitigated the decline in chlorophyll levels and improved stomatal traits,gaseous exchange and F_(v)/F_(m)(13%).Results suggested that the favorable outcomes of melatonin treatment can be associated with elevated antioxidant enzyme activity and an increase in non-enzymatic antioxidants and osmo-protectants.Overall,these findings indicate that exogenous melatonin can improve heat stress tolerance in sweetpotatoes.This stu dy will assist re searchers in further investigating how melatonin makes sweetpotatoes more resistant to heat stress. 展开更多
关键词 SWEETPOTATO Heat stress MELATONIN Oxidative damage antioxidant defense system Stomatal traits
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PHENOLIC ANTIOXIDANTS DETERMINATION IN FOOD ITEMS USING REVERSED-PHASE HPLC 被引量:1
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作者 陈锡进 张志才 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期218-223,共6页
The determination of synthetic phenolic antioxidants (SPAs) including propyl gallate (PG), tertiary butyl hydroquinone (TI3HQ), butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in food items... The determination of synthetic phenolic antioxidants (SPAs) including propyl gallate (PG), tertiary butyl hydroquinone (TI3HQ), butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in food items is reported using high performance liquid chromatography (HPLC). A Cls column is used as the stationary phase, acetonltrile and water:Acetic acid (1%) is used as the mobile phase of gradient elution and the UV detec- tor is set at 280 nm. Under the above conditions, four antioxidents is completely separated within 8 rain. The limit of detection, linear range, and reproducibility of HPLC are evaluated. Isolation parameters of SPAs from different types of food items (cooking oil, margarine and butter, and cheese) are optimized. SPAs are extracted from food items through extraction with methanol/acetonitrile (1 : 1, in volume), vortex, ultrasonic treatment and precipitation in a freezer (2 h). For cooking oil margarine, butter and cheese at 50 and 200 rag/L, recoveries of SPAs are 93.3%0--108.3% (PG), 85.3~^--108.3~~ (TBHQ), 96.7~^--101.2~/6 (BHA), and 73.9^-- 94.6% (BHT). The method is applied to the determination of SPAs in 38 food items (16 cooking oils, 8 mar- garine, 6 butter and 6 cheese samples). The levels of SPAs in positive samples are all below the legal limits of China. 展开更多
关键词 phenolic antioxidants (PAs) high performance liquid chromatography (HPLC) gradient elutionfood
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DFT Study on Molecular Structures and ROS Scavenging Mechanisms of Novel Antioxidants from Lespedeza Virgata
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作者 李敏杰 张良苗 +1 位作者 刘卫霞 陆文聪 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期173-180,I0003,共9页
The molecular structure and radical scavenging activity of three novel antioxidants from Lespedeza Virgata, lespedezavirgatol, lespedezavirgatal, and lespedezacoumestan, have been studied using density functional theo... The molecular structure and radical scavenging activity of three novel antioxidants from Lespedeza Virgata, lespedezavirgatol, lespedezavirgatal, and lespedezacoumestan, have been studied using density functional theory with the B3LYP and BhandHLYP methods. The optimized geometries of neutral, radical cation, radical and anion forms were obtained at the B3LYP/6-31G(d) level, in which it was found that all the most stable conformations contain intramolecular hydrogen bonds. The same results were obtained from the MP2 method. The homolytic O-H bond dissociation enthalpy and the adiabatic ionization potential of neutral and anion forms for the three new antioxidants and adiabatic electron affinity and H-atom affinity for hydroxyl radical, superoxide anion radical, and hydrogen peroxide radical were determined both in gas phase and in aqueous solution using IEF-PCM and CPCM model with UAHF or Bondi cavity. The antioxidant activities and reactive oxygen species scavenging mechanisms were then discussed, and the results obtained from different methods are consistent. Furthermore, the antioxidant activities are consistent with the experimental findings of the compounds under investigation. 展开更多
关键词 Molecular structure Reactive oxygen species scavenging mechanism Novel antioxidant Density functional theory
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Phytochemical analysis and antioxidants activities of aqueous stem bark extract of Schotia latifolia Jacq 被引量:15
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作者 Mbaebie BO Edeoga HO Afolayan AJ 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第2期118-124,共7页
Objective:To evaluate the phytochemical constituents and antioxidant activities of aqueous extract of Scholia latifolia(S.latifolia)bark locally used for the treatment of oxidative stress-induced ailments in South Afr... Objective:To evaluate the phytochemical constituents and antioxidant activities of aqueous extract of Scholia latifolia(S.latifolia)bark locally used for the treatment of oxidative stress-induced ailments in South Africa.Methods:The antioxidant and free radical scavenging activity of aqueous extract of the plant was assessed against 1,1-diphenyl-2-pierylhydrazyl(DPPH),nitric oxide(NO),2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt(ABTS)and the ferric reducing agent.Total phenolics,flavonoids,flavonols and proanthocyanidins were also determined to assess their corresponding effect on the antioxidant activity of this plant.Results:The activities of plant extract against DPPH,ABTS and NO radicals were concentration dependent with IC_(50)value of 0.06,0.05 and 0.05 mg/mL,respectively.The reducing power of the extract was greater than that of butylated hydroxyl toluene(BHT)and ascorbic acid which were used as standard drugs in a concentration dependent manner.The total phenolics content of the aqueous bark extract was(193.33±0.03 TE/g),followed by flavonoids(72.70±0.01 QE/g),proanthocyanidins|48.76±0.00 CE/g)and flavonols(47.76±0.21 QE/g).Phytochemical analysis revealed the presence of percentage tannin(11.40±0.02),alkaloid(9.80±0.01),steroids(18.20±0.01),glycosides(29.80±0.01)and saponins(6.80±0.00).The results exhibited a positive linear correlation between these polyphenols and the free radical scavenging activities.Conclusions:Our findings provide evidence that the crude aqueous extract of S.latifolia is a potential source of natural antioxidants and this justifies its uses in folkloric medicines. 展开更多
关键词 Schotia LATIFOLIA Free radicals PHYTOCHEMICAL antioxidANT ACTIVITY Oxidative stress Natural antioxidANT Reducing power Phenolics Flavonoids SCAVENGING ACTIVITY POLYPHENOL
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Relationships among alcoholic liver disease,antioxidants,and antioxidant enzymes 被引量:16
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作者 Kyu-Ho Han Naoto Hashimoto Michihiro Fukushima 《World Journal of Gastroenterology》 SCIE CAS 2016年第1期37-49,共13页
Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide.The metabolism of ethanol generates reactive oxygen species,which play a significant role in the deterio-ration of alcoholic l... Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide.The metabolism of ethanol generates reactive oxygen species,which play a significant role in the deterio-ration of alcoholic liver disease(ALD).Antioxidant phytochemicals,such as polyphenols,regulate the expression of ALD-associated proteins and peptides,namely,catalase,superoxide dismutase,glutathione,glutathione peroxidase,and glutathione reductase.These plant antioxidants have electrophilic activity and may induce antioxidant enzymes via the Kelch-like ECH-associated protein 1--NF--E2--related factor--2 pathway and antioxidant responsive elements.Furthermore,these antioxidants are reported to alleviate cell injury caused by oxidants or inflammatory cytokines.These phenomena are likely induced via the regulation of mitogen--activating protein kinase(MAPK)pathways by plant antioxidants,similar to preconditioning in ischemia-reperfusion models.Although the relationship between plant antioxidants and ALD has not been adequately investigated,plant antioxidants may be preventive for ALD because of their electrophilic and regulatory activities in the MAPK pathway. 展开更多
关键词 ELECTROPHILE Mitogen-activating PROTEINKINASE Plant antioxidants reactive oxygen species PRECONDITIONING
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The research and development on the antioxidants in prevention of diabetic complications 被引量:10
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作者 Mohammad Rahimi-Madiseh Afsaneh Malekpour-Tehrani +1 位作者 Mahmoud Bahmani Mahmud Rafieian-kopaei 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第9期801-808,共8页
Diabetes mellitus can damage the eyes,kidneys,nerves and heart.Microvascular and macrovascular disorders are the leading causes of morbidity and mortality in diabetic patients.Hyperglycemia can increase the indicators... Diabetes mellitus can damage the eyes,kidneys,nerves and heart.Microvascular and macrovascular disorders are the leading causes of morbidity and mortality in diabetic patients.Hyperglycemia can increase the indicators of lipid peroxidation and oxidative stress in which free radicals have the main role in the pathogenesis of these complications.Therefore,antioxidants which combat oxidative stress should be able to prevent and repair free radicals induced damages.Although free radicals contribute to kidney damage,atherosclerosis,diabetes,heart disease,nephrotoxicity and hepatotoxicity; however,clinical trials do not uniquely confirm a substantial impact on diabetic damage.It seems that antioxidants in vegetables,fruits and grains help preventing diabetes complications; however,there is little evidence that taking single antioxidants such as vitamin E or vitamin C protect these complications.The findings about combination antioxidants are also complicated and not entirely clear.In this review paper we tried to present the role of oxidative stress on microvascular complications of type2 diabetes mellitus.Other objective of this paper is to review the new findings about the role of various antioxidants on prevention and treatment of diabetes mellitus as well as its complications including retinopathy,nephropathy and neuropathy. 展开更多
关键词 DIABETIC NEPHROPATHY Natural antioxidants Diabetes COMPLICATIONS NEPHROPATHY NEUROPATHY RETINOPATHY
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Oxidative stress and antioxidants in hepatic pathogenesis 被引量:20
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作者 Hye-Lin Ha Hye-Jun Shin +1 位作者 Mark A Feitelson Dae-Yeul Yu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第48期6035-6043,共9页
Long term hepatitis B virus (HBV) infection is a major risk factor in pathogenesis of chronic liver diseases,including hepatocellular carcinoma (HCC). The HBV encod-ed proteins,hepatitis B virus X protein and preS,app... Long term hepatitis B virus (HBV) infection is a major risk factor in pathogenesis of chronic liver diseases,including hepatocellular carcinoma (HCC). The HBV encod-ed proteins,hepatitis B virus X protein and preS,appear to contribute importantly to the pathogenesis of HCC. Both are associated with oxidative stress,which can damage cellular molecules like lipids,proteins,and DNA during chronic infection. Chronic alcohol use is another important factor that contributes to oxidative stress in the liver. Previous studies reported that treatment with antioxidants,such as curcumin,silymarin,green tea,and vitamins C and E,can protect DNA from damage and regulate liver pathogenesis-related cascades by reducing reactive oxygen species. This review summarizes some of the relationships between oxidative stress and liver pathogenesis,focusing upon HBV and alcohol,and suggests antioxidant therapeutic approaches. 展开更多
关键词 HEPATITIS B VIRUS HEPATITIS B VIRUS X protein ALCOHOL Chronic liver disease Oxidative stress antioxidant
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Relationship of nocturnal concentrations of melatonin, gamma-aminobutyric acid and total antioxidants in peripheral blood with insomnia after stroke: study protocol for a prospective non-randomized controlled trial 被引量:50
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作者 Wei Zhang Fang Li Tong Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第8期1299-1307,共9页
Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective si... Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective single-center non-randomized controlled clinical trial performed in the China Rehabilitation Research Center, we analyzed the relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke. Patients during rehabilitation of stroke were recruited and assigned to the insomnia group or non-insomnia group. Simultaneously, persons without stroke or insomnia served as normal controls. Each group contained 25 cases. The primary outcome was nocturnal concentrations of melatonin, GABA and total antioxidants in peripheral blood. The secondary outcomes were Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Morningness-Eveningness Questionnaire(Chinese version), and National Institute of Health Stroke Scale. The relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke was analyzed and showed that they were lower in the insomnia group than in the non-insomnia group. The severity of stroke was higher in the insomnia group than in the non-insomnia group. Correlation analysis demonstrated that the nocturnal concentrations of melatonin and GABA were associated with insomnia after stroke. This trial was registered at Clinical Trials.gov, identifier: NCT03202121. 展开更多
关键词 nerve regeneration STROKE INSOMNIA MELATONIN γ-aminobutyric acid total antioxidants sleep-related scales National Institute ofHealth Stroke Scale neural regeneration
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Evaluation of anti-apoptotic activity of different dietary antioxidants in renal cell carcinoma against hydrogen peroxide 被引量:4
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作者 Garg Neeraj K Mangal Sharad +3 位作者 Sahu Tejram Mehta Abhinav Vyas Suresh P Tyagi Rajeev K 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第1期57-63,共7页
Objective:To evaluate the anti-apoptotic and radical scavenging activities of dietary phenolics, namely ascorbic acid,a-tocopherol acetate,citric acid,salicylic acid,and estimate H_2O_2induced apoptosis in renal cell ... Objective:To evaluate the anti-apoptotic and radical scavenging activities of dietary phenolics, namely ascorbic acid,a-tocopherol acetate,citric acid,salicylic acid,and estimate H_2O_2induced apoptosis in renal cell carcinoma cells.Methods:The intracellular antioxidant potency of antioxidants was investigated.H_2O-2-induced apoptosis in RCC-26 was assayed with the following parameters:cell viability(%apoptosis),nucleosomal damage and DNA fragmentation, bcl-2 levels and flow cytometery analysis(ROS production evaluation).Results:Ine anticancer properties of antioxidants such as ascorbic acid,a- tocopherol acetate,citric acid,salicylic acid with perdurable responses were investigated.It was observed that these antioxidants had protective effect(anti-apoptotic activity) against hydrogen peroxide(H_2O_2) in renal cell carcinoma(RCC-26) cell line.Conclusions:This study reveals and proves the anticancer properties.However,in cancer cell lines anti-apoptotic activity can indirectly reflect the cancer promoter activity through radicals scavenging,and significantly protect nucleus and bcl-2. 展开更多
关键词 antioxidants ANTICANCER Apoptosis ROS Hydrogen PEROXIDE RCC-26
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Effect of Commiphora mukul gum resin on hepatic marker enzymes,lipid peroxidation and antioxidants status in pancreas and heart of streptozotocin induced diabetic rats 被引量:3
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作者 Ramesh B Karuna R +4 位作者 Sreenivasa Reddy S Haritha K Sai Mangala D Sasi Bhusana Rao B Saralakumari D 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第11期895-900,共6页
Objective:To study the antioxidant efficacy of Commiphora mukul(C.mukul) gum resin ethanolic extract in streptozotocin(STZ) induced diabetic rats.Methods:The male Wistar albino rats were randomly divided into four gro... Objective:To study the antioxidant efficacy of Commiphora mukul(C.mukul) gum resin ethanolic extract in streptozotocin(STZ) induced diabetic rats.Methods:The male Wistar albino rats were randomly divided into four groups of eight animals each:Control group(C),CM-treated control group(C_+CMEE),Diabetic control group(D),CM- treated diabetic group(D_+CMEE).Diabetes was induced by intraperitoneal injection of STZ(55 mg/kg/ bwt).After being confirmed the diabetic rats were treated with C.mukul gum resin ethanolic extract(CMEE) for 60 days.The biochemical estimations like antioxidant,oxidative stress marker enzymes and hepatic marker enzymes of tissues were performed.Results:The diabetic rats showed increased level of enzymatic activities aspartate aminotransaminase(AST),alanine aminotransaminase(ALT) in liver and kidney and oxidative markers like lipid peroxidation(LPO) and protein oxidation(PO) in pancreas and heart. Antioxidant enzyme activities were significantly decreased in the pancreas and heart compared to control group.Administration of CMEE(200 mg/kg bw) to diabetic rats for 60 days significantly reversed the above parameters towards normalcy.Conclusions:In conclusion,our data indicate the preventive role of C.mukul against STZ-induced diabetic oxidative stress;hence this plant could be used as an adjuvant therapy for the prevention and/or management of diabetes and aggravated antioxidant status. 展开更多
关键词 COMMIPHORA mukul antioxidants Lipid PEROXIDATION STREPTOZOTOCIN
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