Background Weaning causes redox dyshomeostasis in piglets,which leads to hepatic oxidative damage.Microbederived antioxidants(MA)have great potential for anti-oxidat ion.This study aimed to investigate changes in hepa...Background Weaning causes redox dyshomeostasis in piglets,which leads to hepatic oxidative damage.Microbederived antioxidants(MA)have great potential for anti-oxidat ion.This study aimed to investigate changes in hepatic redox system,mitochondrial function and apoptosis after weaning,and effects of MA on growth performance and liver health in weaning piglets.Methods This study consisted of 2 experimets.In the both experiments,piglets were weaned at 21 days of age.In Exp.1,at 21(W0),22(W1),25(W4),28(W7),and 35(W14)days of age,6 piglets were slaughtered at each timepoint.In Exp.2,piglets were divided into 2 groups:one received MA gavage(MA)and the other received saline gavage(CON).At 25 days of age,6 piglets from each group were sacrificed.Results In Exp.1,weaning caused growth inhibition and liver developmental retardation from W0 to W4.The mRNA sequencing between W0 and W4 revealed that pathways related to"regulation of apoptotic process"and"reactive oxygen species metabolic process"were enriched.Further study showed that weaning led to higher hepatic content of reactive oxygen species(ROS),H_(2)O_(2) and O_(2)~-.Weaning enhanced mitochondrial fission and suppressed their fusion,activated mitophagy,thus triggering cell apoptosis.In Exp.2,MA improved growth performance of piglets with higher average daily gain(ADG)and average daily feed intake(ADFI).The hepatic ROS,as well as products of oxidative damage malonaldehyde(MDA)and 8-hydroxy-2'-deoxyguanosine(8-OHdG)in the MA group decreased significantly than that of the CON group.The MA elevated mitochondrial membrane potential,increased activity of mitochondrial respiratory chain complexes(MRC)ⅠandⅣ,enhanced mitochondrial fusion and reduced mitophagy thus decreasing cell apoptosis.Conclusions The present study showed that MA improved the growth performance of weaning piglets and reversed weaning-induced oxidative damage,mitochondrial dysfunction,and apoptosis.Our results suggested that MA had promising prospects for maintaining liver health in weaning piglets and provided a reference for studies of liver diseases in humans.展开更多
Background Heat stress has severe negative consequences on performance and health of pigs,leading to significant economic losses.The objective of this study was to investigate the effects of supplemental vitamin E and...Background Heat stress has severe negative consequences on performance and health of pigs,leading to significant economic losses.The objective of this study was to investigate the effects of supplemental vitamin E and a botanical extract in feed or drinking water on growth performance,intestinal health,and oxidative and immune status in grow-ing pigs housed under heat stress conditions.Methods Duplicate experiments were conducted,each using 64 crossbred pigs with an initial body weight of 50.7±3.8 and 43.9±3.6 kg and age of 13-week and 12-week,respectively.Pigs(n=128)were housed individually and assigned within weight blocks and sex to a 2×4 factorial arrangement consisting of 2 environments(thermo-neutral(21.2℃)or heat-stressed(30.9℃))and 4 supplementation treatments(control diet;control+100 IU/L of D-α-tocopherol in water;control+200 IU/kg of DL-α-tocopheryl-acetate in feed;or control+400 mg/kg of a botanical extract in feed).Results Heat stress for 28 d reduced(P≤0.001)final body weight,average daily gain,and average daily feed intake(-7.4 kg,-26.7%,and-25.4%,respectively)but no effects of supplementation were detected(P>0.05).Serum vitamin E increased(P<0.001)with vitamin E supplementation in water and in feed(1.64 vs.3.59 and 1.64 vs.3.24),but not for the botanical extract(1.64 vs.1.67 mg/kg)and was greater when supplemented in water vs.feed(P=0.002).Liver vitamin E increased(P<0.001)with vitamin E supplementations in water(3.9 vs.31.8)and feed(3.9 vs.18.0),but not with the botanical extract(3.9 vs.4.9 mg/kg).Serum malondialdehyde was reduced with heat stress on d 2,but increased on d 28(interaction,P<0.001),and was greater(P<0.05)for antioxidant supplementation compared to control.Cellular proliferation was reduced(P=0.037)in the jejunum under heat stress,but increased in the ileum when vitamin E was supplemented in feed and water under heat stress(interaction,P=0.04).Tumor necrosis factor-αin jejunum and ileum mucosa decreased by heat stress(P<0.05)and was reduced by vitamin E sup-plementations under heat stress(interaction,P<0.001).Conclusions The addition of the antioxidants in feed or in drinking water did not alleviate the negative impact of heat stress on feed intake and growth rate of growing pigs.展开更多
Groundwater contamination near landfills is commonly caused by leachate leakage,and permeable reactive barriers(PRBs)are widely used for groundwater remediation.However,the deactivation and blockage of the reactive me...Groundwater contamination near landfills is commonly caused by leachate leakage,and permeable reactive barriers(PRBs)are widely used for groundwater remediation.However,the deactivation and blockage of the reactive medium in PRBs limit their long-term effectiveness.In the current study,a new methodology was proposed for the in situ regeneration of PRB to remediate leachate-contaminated groundwater.CO_(2)coupled with oxidants was applied for the dispersion and regeneration of the fillers;by injecting CO_(2)to disperse the fillers,the permeability of the PRB was increased and the oxidants could flow evenly into the PRB.The results indicate that the optimumfiller proportion was zero-valent iron(ZVI)/zeolites/activated carbon(AC)=3:8:10 and the optimum oxidant proportion was COD/Na_(2)S_(2)O_(8)/H_(2)O_(2)/Fe^(2+)=1:5:6:5;the oxidation system of Fe^(2+)/H_(2)O_(2)/S_(2)O_(8)^(2−)has a high oxidation efficiency and persistence.The average regeneration rate of zeolites was 72.71%,and the average regeneration rate of AC was 68.40%;the permeability of PRB also increased.This technology is effective for the remediation of landfills in China that have large contaminated areas,an uneven pollutant concentration distribution,and a long pollution duration.The purification mode of long-term adsorption and short-time in situ oxidation can be applied to the remediation of long-term high-concentration organically polluted groundwater,where pollution sources are difficult to cut off.展开更多
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
Cyclops of zooplankton propagates prolifically in eutrophic waterbody and it cannot be exterminated by conventional disinfection process. The mutagenicity of Mesocyclops leukarti and its extermination with oxidants in...Cyclops of zooplankton propagates prolifically in eutrophic waterbody and it cannot be exterminated by conventional disinfection process. The mutagenicity of Mesocyclops leukarti and its extermination with oxidants in a drinking waterworks in China were studied. Among five oxidants for use in bench-scale, chlorine dioxide is the most effective and the potassium per-manganate is the weakest against Mesocyclops leukarti under the same conditions. Full-scale results showed that Mesocyclops leukarti could be effectively removed from water by 1.0 mg/L chlorine dioxide preoxidation combined with conventional removal physical process. After filtration, chlorite, a by-product of prechlorine dioxide, is stable at 0.45 mg/L, which is lower than the critical value of the USEPA. GC-MS examination and Ames test further showed that the quantity of organic substance and the mutagenicity in water treated by chlorine dioxide preoxidation are obviously less than those of prechlorination.展开更多
The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different o...The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different oxidants(e.g.,persulfate(PS),peroxymonosulfate(PMS),and ozone(O3)),including EAOPs-PS systems,EAOPs-PMS systems,EAOPs-peroxone systems,and photoelectro-oxidants systems,for the organic compounds degradation.The coupling system of EAOPs with oxidants is an effective way to improve the generated free radicals(e.g.,HO^·and SO4^·-) concentration and to accelerate pollutant degradation.In this review,we make a summary of the homogeneous and heterogeneous EAOPs-oxidant processes.The reaction mechanisms of EAOPs combined with different oxidants are elucidated in detail,as well as the synergistic effect for improving the degradation and mineralization efficiency.展开更多
The degradation capacity of advanced oxidants generated from oxygen reduction was investigated in model effluent containing chlorobenzene, aniline and benzene through the advanced oxidation processes(AOPs). Intermedia...The degradation capacity of advanced oxidants generated from oxygen reduction was investigated in model effluent containing chlorobenzene, aniline and benzene through the advanced oxidation processes(AOPs). Intermediate products of the degradation process were determined by GC–MS, and they contributed to specify the degradation pathways of monoaromatic compounds. The study particularly focused on the influence of the dosage of the oxidant, pH and the initial concentration of organic compounds on the degradation effectiveness.When the dosage of oxidant was 4 wt% and the pH was 7, the maximum degradation rates of 74.83% chlorobenzene, 70.32% aniline and 37.69% benzene were achieved. Furthermore, microwave was applied to intensify the oxidation process under optimal operation conditions, and the degradation rates were increased to 87.85% chlorobenzene, 89.11% aniline and 39.03% benzene, respectively.展开更多
Itch（pruritus） is one of the most disabling syndromes in patients suffering from skin, liver, or kidney diseases. Our previous study highlighted a key role of oxidative stress in acute itch. Here, we evaluated the e...Itch（pruritus） is one of the most disabling syndromes in patients suffering from skin, liver, or kidney diseases. Our previous study highlighted a key role of oxidative stress in acute itch. Here, we evaluated the effects of antioxidants in mouse models of acute and chronic itch and explored the potential mechanisms. The effects of systemic administration of the antioxidants N-acetyl-Lcysteine（NAC） and N-tert-butyl-a-phenylnitrone（PBN）were determined by behavioral tests in mouse models of acute itch induced by compound 48/80 or chloroquine, and chronic itch by treatment with a mixture of acetonediethyl-ether-water. We found that systemic administration of NAC or PBN significantly alleviated compound 48/80-and chloroquine-induced acute itch in a dose-dependent manner, attenuated dry skin-induced chronic itch, and suppressed oxidative stress in the affected skin.Antioxidants significantly decreased the accumulation of intracellular reactive oxygen species directly induced by compound 48/80 and chloroquine in the cultured dorsal root ganglia-derived cell line ND7-23. Finally, the antioxidants remarkably inhibited the compound 48/80-induced phosphorylation of extracellular signal-regulated kinase in the spinal cord. These results indicated that oxidative stress plays a critical role in acute and chronic itch in the periphery and spinal cord and antioxidant treatment may be a promising strategy for anti-itch therapy.展开更多
Ischemia as a serious neurodegenerative disorder causes together with reperfusion injury many changes in nervous tissue. Most of the neuronal damage is caused by complex of biochemical reactions and substantial proces...Ischemia as a serious neurodegenerative disorder causes together with reperfusion injury many changes in nervous tissue. Most of the neuronal damage is caused by complex of biochemical reactions and substantial processes, such as protein agregation, reactions of free radicals, insufficient blood supply, glutamate excitotoxicity, and oxidative stress. The result of these processes can be apoptotic or necrotic cell death and it can lead to an irreversible damage. Therefore, neuroprotection and prevention of the neurodegeneration are highly important topics to study. There are several approaches to prevent the ischemic damage. Use of many modern therapeutical methods and the incorporation of several substances into the diet of patients is possible to stimulate the endogenous protective mechanisms and improve the life quality.展开更多
Meat color is an intrinsic property that plays a major role in consumer’s perception. Lipid oxidation by-products as well as free iron can adversely affect meat color. This study was to compare the effect of Type I (...Meat color is an intrinsic property that plays a major role in consumer’s perception. Lipid oxidation by-products as well as free iron can adversely affect meat color. This study was to compare the effect of Type I (radical quenching) antioxidants eugenol and rosmarinic acid (RA) to that of Type II (metal chelating) antioxidants milk mineral (MM), phytate, and sodium tri-polyphosphate (STPP) in raw ground chicken patties packed with a single layer of polyvinylchloride (PVC) overwrap. Packaged patties were stored at 4℃ and analyzed on 0, 1, 4, 7, and 10 days for pH, surface color, extent of lipid oxidation, oxymyoglobin content, and microbial load. Color stability was measured using Hunter MiniScan calorimeter (L*, a*, b* values). An effect was observed in L* values (P < 0.05) of meat color between treatments due to the type of antioxidant. Lightness values for STPP and phytate were low and differed (P < 0.05) from eugenol and rosmarinic acid. Milk mineral effectively preserved fresh color and slowed lipid oxidation in chicken patties by day 10. Aerobic plate counts increased over the entire testing period while values for lightness, redness, yellowness and chroma decreased indicating an increase in pH favored microbial spoilage of the meat or vice versa. By day 10, eugenol and MM were more effective and significantly different (P < 0.05) than STPP in controlling lipid oxidation measured as thiobarbituric acid reactive substances (0.198 mg/kg, 0.198 mg/kg, and 0.268 mg/kg, respectively). A positive correlation (r = 0.24, P < 0.005) between lipid oxidation and color saturation was observed indicating that poultry color darkened with increasing lipid oxidation levels.展开更多
This review focuses on the roles antioxidants and prooxidants in colorectal cancer(CRC).Considerable evidence suggests that environmental factors play key roles in the incidence of sporadic CRC.If pro-oxidant factors ...This review focuses on the roles antioxidants and prooxidants in colorectal cancer(CRC).Considerable evidence suggests that environmental factors play key roles in the incidence of sporadic CRC.If pro-oxidant factors play an etiological role in CRC it is reasonable to expect causal interconnections between the wellcharacterized risk factors for CRC,oxidative stress and genotoxicity.Cigarette smoking,a high dietary consumption of n-6 polyunsaturated fatty acids and alcohol intake are all associated with increased CRC risk.These risk factors are all pro-oxidant stressors and their connections to oxidative stress,the intestinal microbiome,intestinal microfold cells,cyclooxygenase-2 and CRCare detailed in this review.While a strong case can be made for pro-oxidant stressors in causing CRC,the role of food antioxidants in preventing CRC is less certain.It is clear that not every micronutrient with antioxidant activity can prevent CRC.It is plausible,however,that the optimal food antioxidants for preventing CRC have not yet been critically evaluated.Increasing evidence suggests that RRR-gamma-tocopherol(the primary dietary form of vitamin E)or other"non-alpha-tocopherol"forms of vitamin E(e.g.,tocotrienols)might be effective.Aspirin is an antioxidant and its consumption is linked to a decreased risk of CRC.展开更多
Numerous studies have implicated oxidative stress in the development of complications of diabetes.During hyperglycemia,production of oxidant agents such as reactive oxygen species and reactive nitrogen species increas...Numerous studies have implicated oxidative stress in the development of complications of diabetes.During hyperglycemia,production of oxidant agents such as reactive oxygen species and reactive nitrogen species increases.This process,along with a decrease in the activity of antioxidant enzymes,induces oxidative stress in the body.This redox imbalance causes damage to vital biomolecules such as proteins,lipids and DNA and results in the generation of harmful products for the body.Mechanisms associated with the creation of oxidative stress conditions and subsequently complications of diabetes are explained through several pathways such as flux through the polyol pathway,intracellular production of advanced glycation end products precursors,protein kinase-C activation,and increased activities of the hexosamine pathway.On the other hand,the study of polymorphism in the antioxidant enzymes genes indicates that some of the gene polymorphisms reduce the antioxidant power of the enzymes.This article aims to review various studies to demonstrate the effect of oxidative stress on the pathogenesis of diabetes and the positive role of antioxidants on diabetic complications.展开更多
Reactive oxygen species are the intermediates that are formed during the normal metabolic process which are effectively neutralized by the antioxidant system of the body.Any imbalance in this neutralization process ca...Reactive oxygen species are the intermediates that are formed during the normal metabolic process which are effectively neutralized by the antioxidant system of the body.Any imbalance in this neutralization process causes oxidative stress which has been implicated as one of the cause in diseases such as Alzheimer's disease, cardiovascular disorders, cancer etc. Research has enabled the use of antioxidants as therapeutic agents in the treatment of various diseases. Literature also puts forth the negative effects of using antioxidants in the treatment of diseases. This review is a compilation of both the beneficial and detrimental effects of use of antioxidants in the treatment of diseases such as cancer, cardiovascular diseases, diabetes and oral diseases.展开更多
The alpha class glutathione s-transferase (GST) isozyme GSTA4-4 (EC2.5.1.18) exhibits high catalytic efficiency towards 4-hydroxynon-2-enal (4-HNE), a major end product of oxidative stress induced lipid peroxidation. ...The alpha class glutathione s-transferase (GST) isozyme GSTA4-4 (EC2.5.1.18) exhibits high catalytic efficiency towards 4-hydroxynon-2-enal (4-HNE), a major end product of oxidative stress induced lipid peroxidation. Exposure of cells and tissues to heat, radiation, and chemicals has been shown to induce oxidative stress resulting in elevated concentrations of 4-HNE that can be detrimental to cell survival. Alternatively, at physiological levels 4-HNE acts as a signaling molecule conveying the occurrence of oxidative events initiating the activation of adaptive pathways. To examine the impact of oxidative/electrophilic stress in a model with impaired 4-HNE metabolizing capability, we disrupted the Gsta4 gene that encodes GSTA4-4 inmice. The effect of electrophile and oxidants on embryonic fibroblasts (MEF) isolated from wild type (WT) and Gsta4 null mice were examined. Results indicate that in the absence of GSTA4-4, oxidant-induced toxicity is potentiated and correlates with elevated accumulation of 4-HNE adducts and DNA damage. Treatment of Gsta4 null MEF with 1,1,4-tris(acetyloxy)-2(E)-nonene [4-HNE(Ac)3], a pro-drug form of 4-HNE, resulted in the activation and phosphorylation of the c-jun-N-terminal kinase (JNK), extracellular-signal-regulated kinases (ERK 1/2) and p38 mitogen activated protein kinases (p38 MAPK) accompanied by enhanced cleavage of caspase-3. Interestingly, when recombinant mammalian or invertebrate GSTs were delivered to Gsta4 null MEF, activation of stress-related kinases in 4-HNE(Ac)3 treated Gsta4 null MEF were inversely correlated with the catalytic efficiency of delivered GSTs towards 4-HNE. Our data suggest that GSTA4-4 plays a major role in protecting cells from the toxic effects of oxidant chemicals by attenuating the accumulation of 4-HNE.展开更多
A comparative study of two kinds of oxidants（H2O and O3） with the combination of two metal precursors（TMA and La（～iPrCp）3） for atomic layer deposition（ALD） La2O3/Al2O3 nanolaminates is carried out. The effect...A comparative study of two kinds of oxidants（H2O and O3） with the combination of two metal precursors（TMA and La（～iPrCp）3） for atomic layer deposition（ALD） La2O3/Al2O3 nanolaminates is carried out. The effects of different oxidants on the physical properties and electrical characteristics of La2O3/Al2O3 nanolaminates are studied. Initial testing results indicate that La2O3/Al2O3 nanolaminates could avoid moisture absorption in the air after thermal annealing. However, moisture absorption occurs in H2O-based La2O3/Al2O3 nanolaminates due to the residue hydroxyl/hydrogen groups during annealing. As a result, roughness enhancement, band offset variation, low dielectric constant and poor electrical characteristics are measured because the properties of H2O-based La2O3/Al2O3 nanolaminates are deteriorated. Addition thermal annealing effects on the properties of O3-based La2O3/Al2O3 nanolaminates indicate that O3 is a more appropriate oxidant to deposit La2O3/Al2O3 nanolaminates for electron devices application.展开更多
Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidativ...Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA】BHT】DTBP】Q】GT-M】PH-M】GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP】BHT】GA】GT-C】GT-M】Q】PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.展开更多
Context: In case of diabetes, persistent and chronic hyperglycaemia may generate free radicals and reactive oxygen species (ROS), which trigger an oxidative stress. Garlic (Allium sativum) is a rich source of bioactiv...Context: In case of diabetes, persistent and chronic hyperglycaemia may generate free radicals and reactive oxygen species (ROS), which trigger an oxidative stress. Garlic (Allium sativum) is a rich source of bioactive compounds and is used in folk medicine for the treatment of various diseases, including diabetes. Besides, α-tocopherol and magnesium have been shown to possess antioxidative properties. Objective: Protective effects of either a garlic aqueous extract or an association of α-tocopherol and magnesium association upon oxidative stress and dysfunctions in kidney and brain of alloxan-diabetic rats were investigated. Results: Both garlic extract and the combination of α-tocopherol and magnesium were found to normalize many parameters which were shifted to pathological values as a consequence of the alloxan-induced diabetes: plasma creatinine and urea levels were decreased, protein leakage in urine was reduced and cortisol level was brought back to control value. In addition, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities, which were lowered in kidney and brain of diabetic animals, were restored by both treatments and, consequently, level of lipids peroxidation was reduced in these organs, as compared to diabetic animals. Conclusion: Both garlic extract and α-tocopherol + magnesium association display beneficial effects upon nephropathy and oxidative stress in alloxan-diabetic rats. The protective effect of garlic is mainly attributed to antioxidant properties and the presence of phenolic acids and flavonoids.展开更多
Asthma is an allergic disease, characterized as a recurrent airflow limitation, airway hyperreactivity, and chronic inflammation, involving a variety of cells and cytokines. Reactive oxygen species have been proven to...Asthma is an allergic disease, characterized as a recurrent airflow limitation, airway hyperreactivity, and chronic inflammation, involving a variety of cells and cytokines. Reactive oxygen species have been proven to play an important role in asthma. The pathogenesis of oxidative stress in asthma involves an imbalance between oxidant and antioxidant systems that is caused by environment pollutants or endogenous reactive oxygen species from inflammation cells. There is growing evidence that antioxidant treatments that include vitamins and food supplements have been shown to ameliorate this oxidative stress while improving the symptoms and decreasing the severity of asthma. In this review, we summarize recent studies that are related to the mechanisms and biomarkers of oxidative stress, antioxidant treatments in asthma.展开更多
The present study aimed to investigate the effectiveness of the use of some antioxidants-<i>α</i>-tocopherol, n-octyl gallate, L-ascorbic acid 6-palmitate and matcha extract (green tea) as inhibitors of g...The present study aimed to investigate the effectiveness of the use of some antioxidants-<i>α</i>-tocopherol, n-octyl gallate, L-ascorbic acid 6-palmitate and matcha extract (green tea) as inhibitors of grape seeds, walnuts and corn germ oils oxidation. The oxidation was studied in a forced regime during 700 h, by the addition of hydrogen peroxide and Cu<sup>2+</sup> ions. The optimal conditions of the accelerated oxidation process in the analysed systems were established. The progress of lipid oxidation was evaluated by measuring the peroxide value (PV) and conjugated dienes and trienes (CD, CT). A series of secondary products of the lipid oxidation were identified: hexanal, octanal and hydroxy-nonadienal. The intensity of the formation of these compounds during oxidation was monitored. The results of this study showed that the oil samples with the addition of antioxidants showed considerably lower oxidation values compared to the control sample. More effective was the action of L-ascorbic acid 6-palmitate and n-octyl gallate, the optimum concentration <span>was 0.1%. An inhibitory effect of the oxidation process was noted for <i>α</i>-</span>tocopherol and matcha extract, the optimal addition concentration was 1%.展开更多
Two new reagents. dimethylammonium chlorochromale adsrbed on alumina and silicagel are describe as convenient reagents for efficient oxidation of a variety of primary and secondaryalcohols. These two reagents are very...Two new reagents. dimethylammonium chlorochromale adsrbed on alumina and silicagel are describe as convenient reagents for efficient oxidation of a variety of primary and secondaryalcohols. These two reagents are very stable and call be safely used for the oxidation of alcoholscontaining double bond.展开更多
基金supported by the National Natural Science Foundation of China(Gant no.32272903)。
文摘Background Weaning causes redox dyshomeostasis in piglets,which leads to hepatic oxidative damage.Microbederived antioxidants(MA)have great potential for anti-oxidat ion.This study aimed to investigate changes in hepatic redox system,mitochondrial function and apoptosis after weaning,and effects of MA on growth performance and liver health in weaning piglets.Methods This study consisted of 2 experimets.In the both experiments,piglets were weaned at 21 days of age.In Exp.1,at 21(W0),22(W1),25(W4),28(W7),and 35(W14)days of age,6 piglets were slaughtered at each timepoint.In Exp.2,piglets were divided into 2 groups:one received MA gavage(MA)and the other received saline gavage(CON).At 25 days of age,6 piglets from each group were sacrificed.Results In Exp.1,weaning caused growth inhibition and liver developmental retardation from W0 to W4.The mRNA sequencing between W0 and W4 revealed that pathways related to"regulation of apoptotic process"and"reactive oxygen species metabolic process"were enriched.Further study showed that weaning led to higher hepatic content of reactive oxygen species(ROS),H_(2)O_(2) and O_(2)~-.Weaning enhanced mitochondrial fission and suppressed their fusion,activated mitophagy,thus triggering cell apoptosis.In Exp.2,MA improved growth performance of piglets with higher average daily gain(ADG)and average daily feed intake(ADFI).The hepatic ROS,as well as products of oxidative damage malonaldehyde(MDA)and 8-hydroxy-2'-deoxyguanosine(8-OHdG)in the MA group decreased significantly than that of the CON group.The MA elevated mitochondrial membrane potential,increased activity of mitochondrial respiratory chain complexes(MRC)ⅠandⅣ,enhanced mitochondrial fusion and reduced mitophagy thus decreasing cell apoptosis.Conclusions The present study showed that MA improved the growth performance of weaning piglets and reversed weaning-induced oxidative damage,mitochondrial dysfunction,and apoptosis.Our results suggested that MA had promising prospects for maintaining liver health in weaning piglets and provided a reference for studies of liver diseases in humans.
基金YVSG was funded by a doctoral scholarship provided by the Peruvian National Fund,for Scientific,Technological,and Technological Innovation Development(FONDECYT)the funding branch of the National Council for Science,Technological,and Technological Innovation Development(CONCYTEC),Peru(grant contract No 233-2015-FONDECYT).
文摘Background Heat stress has severe negative consequences on performance and health of pigs,leading to significant economic losses.The objective of this study was to investigate the effects of supplemental vitamin E and a botanical extract in feed or drinking water on growth performance,intestinal health,and oxidative and immune status in grow-ing pigs housed under heat stress conditions.Methods Duplicate experiments were conducted,each using 64 crossbred pigs with an initial body weight of 50.7±3.8 and 43.9±3.6 kg and age of 13-week and 12-week,respectively.Pigs(n=128)were housed individually and assigned within weight blocks and sex to a 2×4 factorial arrangement consisting of 2 environments(thermo-neutral(21.2℃)or heat-stressed(30.9℃))and 4 supplementation treatments(control diet;control+100 IU/L of D-α-tocopherol in water;control+200 IU/kg of DL-α-tocopheryl-acetate in feed;or control+400 mg/kg of a botanical extract in feed).Results Heat stress for 28 d reduced(P≤0.001)final body weight,average daily gain,and average daily feed intake(-7.4 kg,-26.7%,and-25.4%,respectively)but no effects of supplementation were detected(P>0.05).Serum vitamin E increased(P<0.001)with vitamin E supplementation in water and in feed(1.64 vs.3.59 and 1.64 vs.3.24),but not for the botanical extract(1.64 vs.1.67 mg/kg)and was greater when supplemented in water vs.feed(P=0.002).Liver vitamin E increased(P<0.001)with vitamin E supplementations in water(3.9 vs.31.8)and feed(3.9 vs.18.0),but not with the botanical extract(3.9 vs.4.9 mg/kg).Serum malondialdehyde was reduced with heat stress on d 2,but increased on d 28(interaction,P<0.001),and was greater(P<0.05)for antioxidant supplementation compared to control.Cellular proliferation was reduced(P=0.037)in the jejunum under heat stress,but increased in the ileum when vitamin E was supplemented in feed and water under heat stress(interaction,P=0.04).Tumor necrosis factor-αin jejunum and ileum mucosa decreased by heat stress(P<0.05)and was reduced by vitamin E sup-plementations under heat stress(interaction,P<0.001).Conclusions The addition of the antioxidants in feed or in drinking water did not alleviate the negative impact of heat stress on feed intake and growth rate of growing pigs.
文摘Groundwater contamination near landfills is commonly caused by leachate leakage,and permeable reactive barriers(PRBs)are widely used for groundwater remediation.However,the deactivation and blockage of the reactive medium in PRBs limit their long-term effectiveness.In the current study,a new methodology was proposed for the in situ regeneration of PRB to remediate leachate-contaminated groundwater.CO_(2)coupled with oxidants was applied for the dispersion and regeneration of the fillers;by injecting CO_(2)to disperse the fillers,the permeability of the PRB was increased and the oxidants could flow evenly into the PRB.The results indicate that the optimumfiller proportion was zero-valent iron(ZVI)/zeolites/activated carbon(AC)=3:8:10 and the optimum oxidant proportion was COD/Na_(2)S_(2)O_(8)/H_(2)O_(2)/Fe^(2+)=1:5:6:5;the oxidation system of Fe^(2+)/H_(2)O_(2)/S_(2)O_(8)^(2−)has a high oxidation efficiency and persistence.The average regeneration rate of zeolites was 72.71%,and the average regeneration rate of AC was 68.40%;the permeability of PRB also increased.This technology is effective for the remediation of landfills in China that have large contaminated areas,an uneven pollutant concentration distribution,and a long pollution duration.The purification mode of long-term adsorption and short-time in situ oxidation can be applied to the remediation of long-term high-concentration organically polluted groundwater,where pollution sources are difficult to cut off.
基金the National Key R&D Program of China(Grant No.2021YFB3803003)the Youth Innova-tion Promotion Association of Chinese Academy of Sciences(Grant No.2023311)+1 种基金Zhejiang Public Welfare Technology Application Research Project(Grant No.LGG22E010013)Class III Peak Discipline of Shanghai-Materials Science and Engineering(High-Energy Beam Intelligent Processing and Green Manufacturing).
文摘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.
基金Project (No. 2003AA601120) supported by the Hi-Tech Researchand Development Program (863) of China
文摘Cyclops of zooplankton propagates prolifically in eutrophic waterbody and it cannot be exterminated by conventional disinfection process. The mutagenicity of Mesocyclops leukarti and its extermination with oxidants in a drinking waterworks in China were studied. Among five oxidants for use in bench-scale, chlorine dioxide is the most effective and the potassium per-manganate is the weakest against Mesocyclops leukarti under the same conditions. Full-scale results showed that Mesocyclops leukarti could be effectively removed from water by 1.0 mg/L chlorine dioxide preoxidation combined with conventional removal physical process. After filtration, chlorite, a by-product of prechlorine dioxide, is stable at 0.45 mg/L, which is lower than the critical value of the USEPA. GC-MS examination and Ames test further showed that the quantity of organic substance and the mutagenicity in water treated by chlorine dioxide preoxidation are obviously less than those of prechlorination.
基金the financial support from the National Natural Science Foundation of China(No. 51878423)Graduate Student’s Research and Innovation Fund of Sichuan University(No.2018YJSY075)
文摘The electrochemical advanced oxidation processes(EAOPs) have been extensively applied in the treatment of organic pollutants degradation.Herein,the mini review provides the coupling systems about EAOPs and different oxidants(e.g.,persulfate(PS),peroxymonosulfate(PMS),and ozone(O3)),including EAOPs-PS systems,EAOPs-PMS systems,EAOPs-peroxone systems,and photoelectro-oxidants systems,for the organic compounds degradation.The coupling system of EAOPs with oxidants is an effective way to improve the generated free radicals(e.g.,HO^·and SO4^·-) concentration and to accelerate pollutant degradation.In this review,we make a summary of the homogeneous and heterogeneous EAOPs-oxidant processes.The reaction mechanisms of EAOPs combined with different oxidants are elucidated in detail,as well as the synergistic effect for improving the degradation and mineralization efficiency.
基金Supported by the Key Technologies R&D Program of China(2011BAE111300)
文摘The degradation capacity of advanced oxidants generated from oxygen reduction was investigated in model effluent containing chlorobenzene, aniline and benzene through the advanced oxidation processes(AOPs). Intermediate products of the degradation process were determined by GC–MS, and they contributed to specify the degradation pathways of monoaromatic compounds. The study particularly focused on the influence of the dosage of the oxidant, pH and the initial concentration of organic compounds on the degradation effectiveness.When the dosage of oxidant was 4 wt% and the pH was 7, the maximum degradation rates of 74.83% chlorobenzene, 70.32% aniline and 37.69% benzene were achieved. Furthermore, microwave was applied to intensify the oxidation process under optimal operation conditions, and the degradation rates were increased to 87.85% chlorobenzene, 89.11% aniline and 39.03% benzene, respectively.
基金supported by grants from the National Natural Science Foundation of China(31371179 and 81300968)the Natural Science Foundation of Jiangsu Province,China(BK20140372)+3 种基金supported by funding from Jiangsu Province,China(2015-JY-029)supported by a grant from Jiangsu Province,China(201310285096X)subject to the second affiliated hospital of Soochow University Preponderant Clinic Discipline Group Project Funding(XKQ2015007)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Itch（pruritus） is one of the most disabling syndromes in patients suffering from skin, liver, or kidney diseases. Our previous study highlighted a key role of oxidative stress in acute itch. Here, we evaluated the effects of antioxidants in mouse models of acute and chronic itch and explored the potential mechanisms. The effects of systemic administration of the antioxidants N-acetyl-Lcysteine（NAC） and N-tert-butyl-a-phenylnitrone（PBN）were determined by behavioral tests in mouse models of acute itch induced by compound 48/80 or chloroquine, and chronic itch by treatment with a mixture of acetonediethyl-ether-water. We found that systemic administration of NAC or PBN significantly alleviated compound 48/80-and chloroquine-induced acute itch in a dose-dependent manner, attenuated dry skin-induced chronic itch, and suppressed oxidative stress in the affected skin.Antioxidants significantly decreased the accumulation of intracellular reactive oxygen species directly induced by compound 48/80 and chloroquine in the cultured dorsal root ganglia-derived cell line ND7-23. Finally, the antioxidants remarkably inhibited the compound 48/80-induced phosphorylation of extracellular signal-regulated kinase in the spinal cord. These results indicated that oxidative stress plays a critical role in acute and chronic itch in the periphery and spinal cord and antioxidant treatment may be a promising strategy for anti-itch therapy.
文摘Ischemia as a serious neurodegenerative disorder causes together with reperfusion injury many changes in nervous tissue. Most of the neuronal damage is caused by complex of biochemical reactions and substantial processes, such as protein agregation, reactions of free radicals, insufficient blood supply, glutamate excitotoxicity, and oxidative stress. The result of these processes can be apoptotic or necrotic cell death and it can lead to an irreversible damage. Therefore, neuroprotection and prevention of the neurodegeneration are highly important topics to study. There are several approaches to prevent the ischemic damage. Use of many modern therapeutical methods and the incorporation of several substances into the diet of patients is possible to stimulate the endogenous protective mechanisms and improve the life quality.
文摘Meat color is an intrinsic property that plays a major role in consumer’s perception. Lipid oxidation by-products as well as free iron can adversely affect meat color. This study was to compare the effect of Type I (radical quenching) antioxidants eugenol and rosmarinic acid (RA) to that of Type II (metal chelating) antioxidants milk mineral (MM), phytate, and sodium tri-polyphosphate (STPP) in raw ground chicken patties packed with a single layer of polyvinylchloride (PVC) overwrap. Packaged patties were stored at 4℃ and analyzed on 0, 1, 4, 7, and 10 days for pH, surface color, extent of lipid oxidation, oxymyoglobin content, and microbial load. Color stability was measured using Hunter MiniScan calorimeter (L*, a*, b* values). An effect was observed in L* values (P < 0.05) of meat color between treatments due to the type of antioxidant. Lightness values for STPP and phytate were low and differed (P < 0.05) from eugenol and rosmarinic acid. Milk mineral effectively preserved fresh color and slowed lipid oxidation in chicken patties by day 10. Aerobic plate counts increased over the entire testing period while values for lightness, redness, yellowness and chroma decreased indicating an increase in pH favored microbial spoilage of the meat or vice versa. By day 10, eugenol and MM were more effective and significantly different (P < 0.05) than STPP in controlling lipid oxidation measured as thiobarbituric acid reactive substances (0.198 mg/kg, 0.198 mg/kg, and 0.268 mg/kg, respectively). A positive correlation (r = 0.24, P < 0.005) between lipid oxidation and color saturation was observed indicating that poultry color darkened with increasing lipid oxidation levels.
文摘This review focuses on the roles antioxidants and prooxidants in colorectal cancer(CRC).Considerable evidence suggests that environmental factors play key roles in the incidence of sporadic CRC.If pro-oxidant factors play an etiological role in CRC it is reasonable to expect causal interconnections between the wellcharacterized risk factors for CRC,oxidative stress and genotoxicity.Cigarette smoking,a high dietary consumption of n-6 polyunsaturated fatty acids and alcohol intake are all associated with increased CRC risk.These risk factors are all pro-oxidant stressors and their connections to oxidative stress,the intestinal microbiome,intestinal microfold cells,cyclooxygenase-2 and CRCare detailed in this review.While a strong case can be made for pro-oxidant stressors in causing CRC,the role of food antioxidants in preventing CRC is less certain.It is clear that not every micronutrient with antioxidant activity can prevent CRC.It is plausible,however,that the optimal food antioxidants for preventing CRC have not yet been critically evaluated.Increasing evidence suggests that RRR-gamma-tocopherol(the primary dietary form of vitamin E)or other"non-alpha-tocopherol"forms of vitamin E(e.g.,tocotrienols)might be effective.Aspirin is an antioxidant and its consumption is linked to a decreased risk of CRC.
文摘Numerous studies have implicated oxidative stress in the development of complications of diabetes.During hyperglycemia,production of oxidant agents such as reactive oxygen species and reactive nitrogen species increases.This process,along with a decrease in the activity of antioxidant enzymes,induces oxidative stress in the body.This redox imbalance causes damage to vital biomolecules such as proteins,lipids and DNA and results in the generation of harmful products for the body.Mechanisms associated with the creation of oxidative stress conditions and subsequently complications of diabetes are explained through several pathways such as flux through the polyol pathway,intracellular production of advanced glycation end products precursors,protein kinase-C activation,and increased activities of the hexosamine pathway.On the other hand,the study of polymorphism in the antioxidant enzymes genes indicates that some of the gene polymorphisms reduce the antioxidant power of the enzymes.This article aims to review various studies to demonstrate the effect of oxidative stress on the pathogenesis of diabetes and the positive role of antioxidants on diabetic complications.
文摘Reactive oxygen species are the intermediates that are formed during the normal metabolic process which are effectively neutralized by the antioxidant system of the body.Any imbalance in this neutralization process causes oxidative stress which has been implicated as one of the cause in diseases such as Alzheimer's disease, cardiovascular disorders, cancer etc. Research has enabled the use of antioxidants as therapeutic agents in the treatment of various diseases. Literature also puts forth the negative effects of using antioxidants in the treatment of diseases. This review is a compilation of both the beneficial and detrimental effects of use of antioxidants in the treatment of diseases such as cancer, cardiovascular diseases, diabetes and oral diseases.
文摘The alpha class glutathione s-transferase (GST) isozyme GSTA4-4 (EC2.5.1.18) exhibits high catalytic efficiency towards 4-hydroxynon-2-enal (4-HNE), a major end product of oxidative stress induced lipid peroxidation. Exposure of cells and tissues to heat, radiation, and chemicals has been shown to induce oxidative stress resulting in elevated concentrations of 4-HNE that can be detrimental to cell survival. Alternatively, at physiological levels 4-HNE acts as a signaling molecule conveying the occurrence of oxidative events initiating the activation of adaptive pathways. To examine the impact of oxidative/electrophilic stress in a model with impaired 4-HNE metabolizing capability, we disrupted the Gsta4 gene that encodes GSTA4-4 inmice. The effect of electrophile and oxidants on embryonic fibroblasts (MEF) isolated from wild type (WT) and Gsta4 null mice were examined. Results indicate that in the absence of GSTA4-4, oxidant-induced toxicity is potentiated and correlates with elevated accumulation of 4-HNE adducts and DNA damage. Treatment of Gsta4 null MEF with 1,1,4-tris(acetyloxy)-2(E)-nonene [4-HNE(Ac)3], a pro-drug form of 4-HNE, resulted in the activation and phosphorylation of the c-jun-N-terminal kinase (JNK), extracellular-signal-regulated kinases (ERK 1/2) and p38 mitogen activated protein kinases (p38 MAPK) accompanied by enhanced cleavage of caspase-3. Interestingly, when recombinant mammalian or invertebrate GSTs were delivered to Gsta4 null MEF, activation of stress-related kinases in 4-HNE(Ac)3 treated Gsta4 null MEF were inversely correlated with the catalytic efficiency of delivered GSTs towards 4-HNE. Our data suggest that GSTA4-4 plays a major role in protecting cells from the toxic effects of oxidant chemicals by attenuating the accumulation of 4-HNE.
基金supported by the National Natural Science Foundation of China(Grant Nos.61604016 and 51501017)the Fundamental Research Funds for the Central Universities,China(Grant No.310831161003)
文摘A comparative study of two kinds of oxidants（H2O and O3） with the combination of two metal precursors（TMA and La（～iPrCp）3） for atomic layer deposition（ALD） La2O3/Al2O3 nanolaminates is carried out. The effects of different oxidants on the physical properties and electrical characteristics of La2O3/Al2O3 nanolaminates are studied. Initial testing results indicate that La2O3/Al2O3 nanolaminates could avoid moisture absorption in the air after thermal annealing. However, moisture absorption occurs in H2O-based La2O3/Al2O3 nanolaminates due to the residue hydroxyl/hydrogen groups during annealing. As a result, roughness enhancement, band offset variation, low dielectric constant and poor electrical characteristics are measured because the properties of H2O-based La2O3/Al2O3 nanolaminates are deteriorated. Addition thermal annealing effects on the properties of O3-based La2O3/Al2O3 nanolaminates indicate that O3 is a more appropriate oxidant to deposit La2O3/Al2O3 nanolaminates for electron devices application.
文摘Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA】BHT】DTBP】Q】GT-M】PH-M】GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP】BHT】GA】GT-C】GT-M】Q】PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.
文摘Context: In case of diabetes, persistent and chronic hyperglycaemia may generate free radicals and reactive oxygen species (ROS), which trigger an oxidative stress. Garlic (Allium sativum) is a rich source of bioactive compounds and is used in folk medicine for the treatment of various diseases, including diabetes. Besides, α-tocopherol and magnesium have been shown to possess antioxidative properties. Objective: Protective effects of either a garlic aqueous extract or an association of α-tocopherol and magnesium association upon oxidative stress and dysfunctions in kidney and brain of alloxan-diabetic rats were investigated. Results: Both garlic extract and the combination of α-tocopherol and magnesium were found to normalize many parameters which were shifted to pathological values as a consequence of the alloxan-induced diabetes: plasma creatinine and urea levels were decreased, protein leakage in urine was reduced and cortisol level was brought back to control value. In addition, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities, which were lowered in kidney and brain of diabetic animals, were restored by both treatments and, consequently, level of lipids peroxidation was reduced in these organs, as compared to diabetic animals. Conclusion: Both garlic extract and α-tocopherol + magnesium association display beneficial effects upon nephropathy and oxidative stress in alloxan-diabetic rats. The protective effect of garlic is mainly attributed to antioxidant properties and the presence of phenolic acids and flavonoids.
基金Supported by The National Natural Science Foundation of China,No.81402988
文摘Asthma is an allergic disease, characterized as a recurrent airflow limitation, airway hyperreactivity, and chronic inflammation, involving a variety of cells and cytokines. Reactive oxygen species have been proven to play an important role in asthma. The pathogenesis of oxidative stress in asthma involves an imbalance between oxidant and antioxidant systems that is caused by environment pollutants or endogenous reactive oxygen species from inflammation cells. There is growing evidence that antioxidant treatments that include vitamins and food supplements have been shown to ameliorate this oxidative stress while improving the symptoms and decreasing the severity of asthma. In this review, we summarize recent studies that are related to the mechanisms and biomarkers of oxidative stress, antioxidant treatments in asthma.
文摘The present study aimed to investigate the effectiveness of the use of some antioxidants-<i>α</i>-tocopherol, n-octyl gallate, L-ascorbic acid 6-palmitate and matcha extract (green tea) as inhibitors of grape seeds, walnuts and corn germ oils oxidation. The oxidation was studied in a forced regime during 700 h, by the addition of hydrogen peroxide and Cu<sup>2+</sup> ions. The optimal conditions of the accelerated oxidation process in the analysed systems were established. The progress of lipid oxidation was evaluated by measuring the peroxide value (PV) and conjugated dienes and trienes (CD, CT). A series of secondary products of the lipid oxidation were identified: hexanal, octanal and hydroxy-nonadienal. The intensity of the formation of these compounds during oxidation was monitored. The results of this study showed that the oil samples with the addition of antioxidants showed considerably lower oxidation values compared to the control sample. More effective was the action of L-ascorbic acid 6-palmitate and n-octyl gallate, the optimum concentration <span>was 0.1%. An inhibitory effect of the oxidation process was noted for <i>α</i>-</span>tocopherol and matcha extract, the optimal addition concentration was 1%.
文摘Two new reagents. dimethylammonium chlorochromale adsrbed on alumina and silicagel are describe as convenient reagents for efficient oxidation of a variety of primary and secondaryalcohols. These two reagents are very stable and call be safely used for the oxidation of alcoholscontaining double bond.
