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A high-quality genome of Actinidia eriantha provides new insight into ascorbic acid regulation
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作者 LIAO Guang-lian HUANG Chun-hui +4 位作者 JIA Dong-feng ZHONG Min TAO Jun-jie QU Xue-yan XU Xiao-biao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第11期3244-3255,共12页
Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecula... Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics,metabolomics and transcriptomics.We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps.The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb.Among them,24 of the pseudochromosomes were obtained directly from telomere-to-telomere.The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively.Subsequently, 61 metabolites and 2 092genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively.AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development,suggesting its crucial role in the regulation of AsA.Furthermore,the AsA contents are highly associated with ascorbate peroxidase genes.The genome obtained in this study provides genomic resources for the genetic and breeding research ofA. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit. 展开更多
关键词 Actinidia eriantha ascorbic acid non-targeted metabolome gapless genome TRANSCRIPTOME
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Appraisal of Improvement in Physiological and Metabolic Processes by Exogenously Applied Natural and Synthetic Ascorbic Acid in Okra(Abelmoschus esculentus L.)Fruit Subjected to Water Deficit Stress
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作者 Muhammad Younis Nudrat Aisha Akram +1 位作者 Arafat Abdel Hamed Abdel Latef Muhammad Ashraf 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第10期2761-2784,共24页
To counteract the effects of drought stress,scientists have adopted several approaches including the use of different chemicals both inorganic and organic,which is contemplated as a highly efficient and cost-effective... To counteract the effects of drought stress,scientists have adopted several approaches including the use of different chemicals both inorganic and organic,which is contemplated as a highly efficient and cost-effective shot-gun approach.Ascorbic acid(AsA)is a potential organic substance,which widely occurs in plants,and is considered to be an effective antioxidant to counteract reactive oxygen species(ROS).Thus,a pot experiment was performed to assess the relative mitigating impacts of synthetic AsA and naturally occurring AsA in the form of lemon juice(LJ)and orange juice(OJ)on two cultivars of okra(Abelmoschus esculentus L.)namely Sabz Pari and Bhindi Sanwali under varying water deficit conditions.After 30 days of seed germination,okra seedlings were subjected to different irrigation regimes,i.e.,water deficit stress[(65%and 50%F.C.)and control conditions(100%F.C.)].Different levels of AsA[control(no spray),14 mg L^(−1)LJ,24 mg L^(−1)OJ and 150 mg L^(−1)AsA]obtained from different sources were applied as a foliar spray to control and water-stressed plants.Drought stress prominently reduced plant growth and yield attributes of the okra cultivars.Water-deficit conditions(65%and 50%F.C.)substantially decreased the fruit chlorophyll(a,b)pigments and the activity of superoxide dismutase(SOD)enzyme,while an increase was observed in the contents of fruit’s hydrogen peroxide(H_(2)O_(2)),malondialdehyde(MDA),total phenolics,total soluble sugars,AsA,and total soluble proteins.Drought stress also increased the activities of antioxidant enzymes like peroxidase(POD)and catalase(CAT).However,plant growth and yield attributes,fruit chlorophyll pigments,total phenolics,total soluble sugars,total free amino acids,total soluble proteins,AsA,GB,H_(2)O_(2),and the activities of antioxidant enzymes(POD and CAT)were increased by the AsA exogenous treatment in both okra cultivars under water deficit and control conditions.Overall,LJ and OJ were more effective than the synthetic AsA in upregulating the physiological and metabolic processes of okra plants.So,cost-effective as well as multi-nutrient natural sources of AsA could be suggested for alleviating the harmful effects of water deficit stress on plants. 展开更多
关键词 OKRA ascorbic acid lemon juice orange juice drought tolerance
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VOLTAMMETRIC BEHAVIOR OF ASCORBIC ACID AT α-CYCLODEXTRIN INCORPORATED CARBON NANOTUBES-COATED ELECTRODE 被引量:2
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作者 肖素芳 王宗花 +1 位作者 王义明 罗国安 《青岛大学学报(自然科学版)》 CAS 2002年第4期1-6,共6页
制备了α -环糊精掺杂纳米碳管涂层电极并应用于抗坏血酸的电催化氧化 ,结果表明 ,氧化电位降低了 2 80mV ,电流响应明显增加。我们首次结合两种物质的特性 :纳米碳管的导电性及催化性能、α -环糊精的分子认知能力 ,对电极表面进行修... 制备了α -环糊精掺杂纳米碳管涂层电极并应用于抗坏血酸的电催化氧化 ,结果表明 ,氧化电位降低了 2 80mV ,电流响应明显增加。我们首次结合两种物质的特性 :纳米碳管的导电性及催化性能、α -环糊精的分子认知能力 ,对电极表面进行修饰。实验了抗坏血酸与α -环糊精超分子络合物的特性。差示脉冲技术用于定量分析抗坏血酸 ,线性范围为 2 .5× 10 -6~ 1.0× 10 展开更多
关键词 伏安行为 Α-环糊精 纳米碳管涂层电级 超分子络 抗坏血酸 电催化氧化
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Protective effect of ascorbic acid on cyclophosphamide induced testicular gametogenic and androgenic disorders in male rats 被引量:27
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作者 Ujjal Baran Das Mousumi Mallick +1 位作者 Jogendra Mohan Debnath Debidas Ghosh 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第3期201-207,共7页
Aim: To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate t... Aim: To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate the protective effect of ascorbic acid. Methods: The testicular △~5, 3β-hydroxysteroid dehydrogenase (HSD), 17β-HSD, peroxidase and catalase activities along with the levels of malondialdehyde (MDA) and conjugated dienes in testicular tissue were measured for the evaluation of testicular oxidative stress. The plasma testosterone (T) level was measured by immunoassay. Various germ cells at stage Ⅶ of spermatogenic cycle were quantified from testicular stained sections. Results: Cyclophosphamide treatment results in a significant inhibition in the testicular △~5, 3β-HSD and 17β-HSD activities, a decrease in plasma T level and a diminution in the counts of various germ cells. Moreover, this treatment was also associated with a significant inhibition of the peroxidase and catalase activities along with high levels of MDA and conjugated dienes in the testis. All these changes were reversed by ascorbic acid co-administration. Conclusion: Cyclophosphamide treatment at the dosage used caused testicular gametogenic and androgenic disorders as well as induced testicular oxidative stress that can be reversed by ascorbic acid co-administration. 展开更多
关键词 CYCLOPHOSPHAMIDE ANDROGENESIS GAMETOGENESIS oxidative stress free radicals ascorbic acid CATALASE PEROXIDASE testosterone
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Effect of Ascorbic Acid and Silicium on Photosynthesis, Antioxidant Enzyme Activity, and Fatty Acid Contents in Canola Exposure to Salt Stress 被引量:9
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作者 Ahmad Bybordi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第10期1610-1620,共11页
The effects of exogenous ascorbic acid and silicium on leaf fresh weigh, seed yield, photosynthesis, changes of the activities of major antioxidant enzymes, nitrate reductase activity, proline accumulation, chlorophyl... The effects of exogenous ascorbic acid and silicium on leaf fresh weigh, seed yield, photosynthesis, changes of the activities of major antioxidant enzymes, nitrate reductase activity, proline accumulation, chlorophyll content, and fatty acid composition were investigated in salt-stressed canola. A hydroponic pot experiment was conducted based on randomized complete block design, factorial arrangement was used with 16 combinations of salinity stress (0, 100, 200, and 300 mmol L-1 NaC1), ascorbic acid (0 and 30 mmol L-1), and silicium (2 and 4 mmol L-1 from potassium silicate) with three replicates. The results showed that salinity significantly decreased leaf area and leaf fresh weight, seed yield, photosynthesis, nitrate reductase activity, chlorophyll content, and seed protein percentage. Conversely, respiration, antioxidant enzymes activity, proline accumulation, and linolenic acid percentage increased due to salt stress. Ascorbic acid application improved photosynthesis and seed yield and mitigated antioxidant enzyme activity. In addition, nitrate reductase activity and chlorophyll a and b were positively affected by ascorbic acid. Regarding silicium application, that was found that leaf area, leaf fresh weight, seed yield and photosynthesis, ascorbate peroxidase activity, nitrate reductase activity, and chlorophyll content increased, while respiration decreased. Furthermore, silicium had not significant effect on antioxidant enzyme activity. In general, ascorbic acid and silicium were involved in the defensive mechanisms against salinity stress and it can be suggested that, ascorbic acid and silicium application had positive effect on canola growth under conditions of salt stress. 展开更多
关键词 ascorbic acid salt stress CANOLA SILICIUM
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Role of dissolved oxygen reduction in improvement inhibition performance of ascorbic acid during copper corrosion in 0.50 mol/L sulphuric acid 被引量:5
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作者 Mohammed A.Amin 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期341-345,共5页
The kinetics of dissolved O_2 reduction and hydrogen evolution reactions on copper surface was studied in naturally aerated and air and O_2-saturated 0.50 mol/L H_2SO_4 solutions using polarization measurements combin... The kinetics of dissolved O_2 reduction and hydrogen evolution reactions on copper surface was studied in naturally aerated and air and O_2-saturated 0.50 mol/L H_2SO_4 solutions using polarization measurements combined with the rotating disc electrode (RDE).The Koutecky-Levich plot indicated that the dissolved O_2 reduction at the copper electrode was an apparent four-electron process.A correlation between the presence of dissolved O_2 and the formation of Cu_2O,confirmed from XRD,was discussed. Ascorbic a... 展开更多
关键词 COPPER Sulphuric acid solutions Corrosion inhibition ascorbic acid RDE O_2 reduction
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The Protective Effect of Ascorbic Acid and Thiamine Supplementation against Damage Caused by Lead in the Testes of Mice 被引量:6
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作者 陕光 唐甜 张孝斌 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第1期68-72,共5页
Lead is a ubiquitous environmental and industrial pollutant that may have toxic effects on the male. Vitamins may protect against toxic effects of lead in the liver and reproductive system, which is confirmed by our i... Lead is a ubiquitous environmental and industrial pollutant that may have toxic effects on the male. Vitamins may protect against toxic effects of lead in the liver and reproductive system, which is confirmed by our initial research. The aim of this study was to further investigate the protective effects of vitamins (ascorbic acid combined with thiamine) on lead acetate (Pb)-induced reproductive toxicities in mice and study the possible mechanisms underlying these effects. Forty-five male mice were randomly divided into 3 groups, 15 mice in each and received daily intragastric administration with control, Pb (20 mg/kg), and Pb+vitamins (ascorbic acid of 420 mg/kg+thiamine of 30 mg/kg) for 6 weeks, respectively. The Pb-treated animals showed significant decreases in the epididymal sperm count and motility compared to the control group, while the Pb+vitamins group had significant increases for these variables. Moreover, an increasing apoptosis of germinal cells induced by Pb was reduced by vitamin treatment. Pb induced the activation of Caspase-3, Fas/Fas-L and Bcl-2 with elevated levels, and the adaptor protein primarily regulated signaling through Fas and required for Fas-induced apoptosis. In conclusion, ascorbic acid combined with thiamine exhibited protective effect on reproductive system by inhibiting Pb-induced excessive cell apoptosis. 展开更多
关键词 LEAD ascorbic acid THIAMINE reproductive toxicity apoptosis
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Mechanism of Ascorbic Acid-induced Reversion Against Malignant Phenotype in Human Gastric Cancer Cells 被引量:5
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作者 YA-XUAN SUN QIU-SHENG ZHENC +2 位作者 GANG LI DE-AN GUO ZI-REN WANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2006年第5期385-391,共7页
Objective To find out the mechanisms of redifferentiation and reversion of malignant human gastric cancer cells induced by ascorbic acid. Methods Human gastric cancer cells grown in the laboratory were used. The Trypa... Objective To find out the mechanisms of redifferentiation and reversion of malignant human gastric cancer cells induced by ascorbic acid. Methods Human gastric cancer cells grown in the laboratory were used. The Trypan blue dye exclusion method was used to determine the cell doubling time. The electrophoresis rate and colonogenic potential were the indices used to measure the rate of redifferentiation. The content of malondialdehyde (MDA) was measured using the thiobarbituric acid (TBA) method. The activities of superoxide dismutase (SOD), catalase (CAT) and the content of H2O2 were evaluated by spectrophotography. Results Six mmol/L ascorbic acid was used as a positive control. Human gastric cancer cells were treated with 75 μm hydrogen peroxide, which alleviated many of the malignant characteristics. For example, the cell surface charge obviously decreased and the electrophoresis rate dropped from 2.21 to 1.10 pm·s^-1·cm^-1 The colonogenic potential, a measure of cell differentiation, decreased 90.2%. After treatment with ascorbic acid, there was a concentration- and time-dependent increase in hydrogen peroxide (H2O2) and the activity of superoxide dismutase (SOD). However, the activity of catalase (CAT) resulted in a concentration- and time-dependent decrease. SOD and 3-amino- 1,2,4-triazole (AT) exhibited some effects, but there were statistically significant differences between the SOD and AT group and the H2O2 group, Conclusions Ascurbic acid induces growth inhibition and redifferentiation of human gastric cancer cells through the production of hydrogen peroxide. 展开更多
关键词 Aminotriazole ascorbic acid CATALASE Gastric cancer Hydrogen peroxide REDIFFERENTIATION Superoxide dismutase
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Electroanalysis and simultaneous determination of dopamine and epinephrine at poly(isonicotinic acid)-modified carbon paste electrode in the presence of ascorbic acid 被引量:4
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作者 Yuan Zhen Zhou Li Juan Zhang +2 位作者 Shuang Li Chen She Ying Dong Xiao Hui Zheng 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期217-220,共4页
A carbon paste electrode modified with electropolymerized fills of isonicotinic acid was developed. The modified electrode shows excellent electrocatalytic activity toward the oxidation of both dopamine (DA) and epi... A carbon paste electrode modified with electropolymerized fills of isonicotinic acid was developed. The modified electrode shows excellent electrocatalytic activity toward the oxidation of both dopamine (DA) and epinephrine (EP). Separation of the reduction peak potentials for dopamine and epinephrine was about 357 mV in pH 5.3 phosphate buffer solution (PBS) and the character was used for the detection DA and EP simultaneously. The peak currents increase linearly with DA and EP concentration over the range of 8.0×10^-5 to 7.0×10^-4 mol/L and 5.0×10^-6 to 1.0×10^-4 mol/L with detection limits of 2×10^-5 and 1×10^-6 mol/L, respectively. The interference studies showed that the modified electrode exhibits excellent selectivity in the presence of large excess of ascorbic acid (AA). 展开更多
关键词 DOPAMINE EPINEPHRINE Isonicotinic acid ascorbic acid Simultaneous determination
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A Multiwall Carbon Nanotube-chitosan Modified Electrode for Selective Detection of Dopamine in the Presence of Ascorbic Acid 被引量:6
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作者 LingYanJIANG ChuanYinLIU LiPingJIANG GuangHanLU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期229-232,共4页
关键词 Nanotube-chitosan modified electrode DOPAMINE ascorbic acid.
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Perioperative topical ascorbic acid for the prevention of phacoemulsification-related corneal endothelial damage:Two case reports and review of literature 被引量:5
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作者 Chia-Yi Lee Hung-Ta Chen +5 位作者 Yi-Jen Hsueh Hung-Chi Chen Chieh-Cheng Huang Yaa-Jyuhn James Meir Chao-Min Cheng Wei-Chi Wu 《World Journal of Clinical Cases》 SCIE 2019年第5期642-649,共8页
BACKGROUND The current case report describes successful phacoemulsification with the aid of perioperative topical ascorbic acid(AA) in two patients with corneal endothelial disorders to prevent postoperative corneal e... BACKGROUND The current case report describes successful phacoemulsification with the aid of perioperative topical ascorbic acid(AA) in two patients with corneal endothelial disorders to prevent postoperative corneal endothelial decompensation.CASE SUMMARY Two eyes of two patients underwent phacoemulsification with pre-existing corneal endothelial disorders including Fuchs corneal endothelial dystrophy(Patient 1) and endotheliitis(Patient 2). Topical AA was applied to both patients at least one month before and after with a frequency of four times per day. After the surgery, both eyes improved best-corrected visual acuity(BCVA) and there was limited human corneal endothelial cell loss without signs of corneal endothelial decompensation, such as deteriorated BCVA or persistent corneal edema during the follow-up of at least two years.CONCLUSION Perioperative administration of topical AA may be an alternative therapy to the triple procedure in patients expecting to undergo cataract surgery. 展开更多
关键词 ascorbic acid Fuchs CORNEAL ENDOTHELIAL DYSTROPHY Endotheliitis Human CORNEAL ENDOTHELIAL cell PHACOEMULSIFICATION Case report
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Efficacy of 1.2L polyethylene glycol plus ascorbic acid for bowel preparations 被引量:4
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作者 Hiroyuki Tamaki Teruyo Noda +5 位作者 Masahiro Morita Akina Omura Atsushi Kubo Chikara Ogawa Toshihiro Matsunaka Mitsushige Shibatoge 《World Journal of Clinical Cases》 SCIE 2019年第4期452-465,共14页
BACKGROUND A low-volume polyethylene glycol(PEG) solution that combines ascorbic acid with PEG-based electrolyte solution(PEG-ASC) is gaining mainstream acceptance for bowel preparation due to reduced volume and impro... BACKGROUND A low-volume polyethylene glycol(PEG) solution that combines ascorbic acid with PEG-based electrolyte solution(PEG-ASC) is gaining mainstream acceptance for bowel preparation due to reduced volume and improved taste.Although several reports showed that bowel preparation with PEG-ASC volume lower than 2.0 L with laxative agents could be an alternative to traditional preparation regimen, the cleansing protocols have not been fully investigated.AIM To evaluate the cleansing efficacy of 1.2 L PEG-ASC solution comparing with 2.0 L PEG electrolyte(PEG-ELS) for bowel preparations.METHODS A randomized, single-blinded, open-label, single-center, non-inferiority study was conducted. In total, 312 Japanese adult patients(aged > 18 years) who underwent colonoscopy were enrolled. Patients were randomly allocated to bowel lavage with either 1.2 L of PEG-ASC solution with at least 0.6 L of an additional clear fluid(1.2 L PEG-ASC group) or 2.0 L of PEG-ELS(PEG-ELS group). Then, 48 mg of sennoside was administered at bedtime on the day before colonoscopy, and the designated drug solution was administered at the hospital on the day of colonoscopy. Bowel cleansing was evaluated using the Boston Bowel Preparation Scale(BBPS). The volume of fluid intake and required time for bowel preparation were evaluated. Furthermore, compliance, patient tolerance,and overall acceptability were evaluated using a patient questionnaire, which was assessed using a visual analog scale.RESULTS In total, 291 patients(1.2 L PEG-ASC group, 148; PEG-ELS group, 143) completed the study. There was no significant difference in successful cleansing, defined as a BBPS score ≥ 2 in each segment, between the two groups(1.2 L PEG-ASC group, 91.9%; PEG-ELS group, 90.2%; 95%CI:-0.03-0.09). The required time for bowel preparation was significantly shorter(164.95 min ± 68.95 min vs 202.16 min± 68.69 min, P < 0.001) and the total fluid intake volume was significantly lower(2.23 L ± 0.55 L vs 2.47 L ± 0.56 L, P < 0.001) in the 1.2 L PEG-ASC group than in the PEG-ELS group. Palatability, acceptability of the volume of solution, and overall acceptability evaluated using a patient questionnaire, which was assessed by the visual analog scale, were significantly better in the 1.2 L PEG-ASC group than in the PEG-ELS group(7.70 cm ± 2.57 cm vs 5.80 cm ± 3.24 cm, P < 0.001). No severe adverse event was observed in each group.CONCLUSION The 1.2 L PEG-ASC solution was non-inferior to the 2.0 L PEG-ELS solution in terms of cleansing efficacy and had better acceptability among Japanese patients. 展开更多
关键词 ascorbic acid BOWEL preparation COLONOSCOPY EFFICACY POLYETHYLENE GLYCOL TOLERABILITY
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Ascorbic acid synthesis and transportation capacity in old laying hens and the effects of dietary supplementation with ascorbic acid 被引量:3
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作者 Liping Gan Hao Fan +1 位作者 Wei Nie Yuming Guo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第1期128-139,共12页
Background: Laying hens over 75 weeks of age commonly show great declines in immunity and production performance.It is unclear whether these declines can be relieved by supplementing with ascorbic acid(AA) in feed.Two... Background: Laying hens over 75 weeks of age commonly show great declines in immunity and production performance.It is unclear whether these declines can be relieved by supplementing with ascorbic acid(AA) in feed.Two trials were conducted to investigate the synthesis and metabolism of AA in layers of different ages and the effects of dietary supplemental AA on the performance and the immune and antioxidant statuses of 78 weeks old hens.Methods: In Exp.1,equal numbers(24 hens) of 35 weeks old(Young) and 75 weeks old(Old) layers were fed the same diet without AA supplementation for 4 weeks.In Exp.2,360 healthy 78 weeks old laying hens were randomly assigned to 4 treatments(basal diet supplemented with 0,0.25,0.5,or 1 g AA/kg diet) in an 8-week feeding trial.Results: The old hens tended to have decreased L-gulonolactone oxidase(GLO) synthase activity in the kidney and liver than that of the young hens(P = 0.07 and P = 0.05,respectively).Compared with the young hens,the old hens had lower hepatic antioxidant capacity allowing for the lower thioredoxin(TXN),thioredoxin reductase(TXNR) and cytochrome b5 reductase(CYB5 R) gene expression(P < 0.05),whereas increased sodium-dependent vitamin C transporter(SVCT) 1 expression levels in the ileum and kidney and enhanced splenic and hepatic AA concentrations(P < 0.05).Dietary supplementation with AA significantly decreased GLO enzyme activity but increased splenic AA concentration and anti-bovine serum albumin IgG levels(P < 0.05) and tended to increase CD4+T lymphocyte numbers(P = 0.06) in serum.Supplementation of 0.25 g AA/kg diet significantly increased hepatic total antioxidant capacity(T-AOC,P < 0.05) relative to the control group.Conclusions: Laying hens could synthesize AA in both the kidney and the liver,though the GLO enzyme activities were 100 times greater in kidneys than in livers.The old laying hens had greater absorption and reabsorption capacity and higher AA retention in some tissues that did the young hens.Dietary supplementation of AA can improve the health of old layers by enhancing immunity and antioxidant capacity. 展开更多
关键词 ascorbic acid ANTIOXIDANT capacity IMMUNITY L-gulonolactone OXIDASE OLD LAYING HENS
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Redifferentiation of Human Gastric Cancer Cells Induced by Ascorbic Acid and Sodium Selenite 被引量:3
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作者 ZHENGQIU-SHENG SUNXI-LING 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第3期223-232,共10页
Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye... Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer. 展开更多
关键词 ascorbic acid Sodium selenite Gastric cancer MALONDIALDEHYDE CATALASE Superoxide dismutase
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Comparative Study of Ascorbic Acid and Tocopherol Concentrations in Hydroponic- and Soil-Grown Lettuces 被引量:4
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作者 Drew N. Buchanan Stanley T. Omaye 《Food and Nutrition Sciences》 2013年第10期1047-1053,共7页
Hydroponically-grown produce may be a way of helping to feed the world a variety of fruits and vegetables, regardless of soil quality, space availability or climate. The objective of this study was to determine whethe... Hydroponically-grown produce may be a way of helping to feed the world a variety of fruits and vegetables, regardless of soil quality, space availability or climate. The objective of this study was to determine whether hydroponicallygrown lettuce contains as much ascorbic acid and tocopherol as soil-grown lettuce. We analyzed four varieties of lettuce, including: Waldmann’s Dark Green, Red Lollo Antago, Red Romaine Annapolis, and Butterleaf. The tocopherol content of hydroponically-grown Waldmann’s Dark Green, Red Lollo Antago, and Red Romaine Annapolis was 229%, 497% and 492% higher, respectively, compared to their soil-grown counterpart. The ascorbic acid content of hydroponically-grown Waldmann’s Dark Green, Red Lollo Antago, and Red Romaine Annapolis was 93%, 171% and 216% higher, respectively, compared to their soil-grown counterparts. Hydroponically grown lettuce varieties are significantly higher in both ascorbic acid and tocopherol content than their soil-grown counterparts, and hydroponic gardening is a viable option for producing nutritious fruits and vegetables. 展开更多
关键词 HYDROPONIC LETTUCE ascorbic acid TOCOPHEROL LEAFY Vegetables
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Ascorbic acid accelerates Wallerian degeneration after peripheral nerve injury 被引量:6
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作者 Lixia Li Yizhou Xu +5 位作者 Xianghai Wang Jingmin Liu Xiaofang Hu Dandan Tan Zhenlin Li Jiasong Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第6期1078-1085,共8页
Wallerian degeneration occurs after peripheral nerve injury and provides a beneficial microenvironment for nerve regeneration.Our previous study demonstrated that ascorbic acid promotes peripheral nerve regeneration,p... Wallerian degeneration occurs after peripheral nerve injury and provides a beneficial microenvironment for nerve regeneration.Our previous study demonstrated that ascorbic acid promotes peripheral nerve regeneration,possibly through promoting Schwann cell proliferation and phagocytosis and enhancing macrophage proliferation,migration,and phagocytosis.Because Schwann cells and macrophages are the main cells involved in Wallerian degeneration,we speculated that ascorbic acid may accelerate this degenerative process.To test this hypothesis,400 mg/kg ascorbic acid was administered intragastrically immediately after sciatic nerve transection,and 200 mg/kg ascorbic acid was then administered intragastrically every day.In addition,rat sciatic nerve explants were treated with 200μM ascorbic acid.Ascorbic acid significantly accelerated the degradation of myelin basic protein-positive myelin and neurofilament 200-positive axons in both the transected nerves and nerve explants.Furthermore,ascorbic acid inhibited myelin-associated glycoprotein expression,increased c-Jun expression in Schwann cells,and increased both the number of macrophages and the amount of myelin fragments in the macrophages.These findings suggest that ascorbic acid accelerates Wallerian degeneration by accelerating the degeneration of axons and myelin in the injured nerve,promoting the dedifferentiation of Schwann cells,and enhancing macrophage recruitment and phagocytosis.The study was approved by the Southern Medical University Animal Care and Use Committee(approval No.SMU-L2015081)on October 15,2015. 展开更多
关键词 ascorbic acid AXON MACROPHAGE MYELIN peripheral nerve injury PHAGOCYTOSIS Schwann cell Wallerian degeneration
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Electro-oxidation of Ascorbic Acid on PVP-stabilized Graphene Electrode 被引量:2
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作者 HAN Dong-fang SHAN Chang-sheng +2 位作者 GUO Li-ping NIU Li HAN Dong-xue 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期287-290,共4页
Polyvinylpyrrolidone-stabilized graphene(PVP-graphene) was synthesized and investigated as a modifier for the determination of ascorbic acid(AA). With PVP acting as stabilizer and dispersant, the resulting PVP-gra... Polyvinylpyrrolidone-stabilized graphene(PVP-graphene) was synthesized and investigated as a modifier for the determination of ascorbic acid(AA). With PVP acting as stabilizer and dispersant, the resulting PVP-graphene material could disperse well into water. And the PVP-graphene modified glassy carbon electrode(PVP-graphene-GCE) showed an obvious electrocatalytical activity toward the oxidation of AA in a phosphate buffer solution(PBS, pH=7.0) with an oxidation potential of AA at 0.052 V vs. AglAgCl(sat. KCl). The calibration curve for APt was linear in a concentration range from 1.0×10^-5 to 5.0×10^-4 mol/L with a correlation coefficient of 0.9998. And the detection limit was found to be 1 μtmol/L. During the oxidation of AA, the π-π interaction of graphene plane with conjugated hexenoic aeid-lactone in AA molecules might play a key role. As a result, an obvious decrease of overpotential was achieved at such a PVP-graphene electrode through a possible adsorption/enrichment process, which will probably trigger potential applications for the electroanalysis of some aromatic and heterocyclic compounds. 展开更多
关键词 GRAPHENE POLYVINYLPYRROLIDONE Electro-oxidation ascorbic acid
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Formation of a cerium conversion coating on magnesium alloy using ascorbic acid as additive.Characterisation and anticorrosive properties of the formed films 被引量:7
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作者 A.P.Loperena I.L.Lehr S.B.Saidman 《Journal of Magnesium and Alloys》 SCIE EI CAS 2016年第4期278-285,共8页
Cerium-based conversion coatings were formed on AZ91D magnesium alloy by immersion of the substrate in solutions containing Ce(NO_(3))_(3),H_(2)O_(2) and ascorbic acid(HAsc).The characterisation of the films was perfo... Cerium-based conversion coatings were formed on AZ91D magnesium alloy by immersion of the substrate in solutions containing Ce(NO_(3))_(3),H_(2)O_(2) and ascorbic acid(HAsc).The characterisation of the films was performed by electrochemical and surface analysis techniques such as SEM,EDS,X-ray diffraction and X-ray photoelectron spectroscopy(XPS).The degree of corrosion protection achieved was evaluated in simulated physiological solution by the open circuit potential monitoring,polarisation techniques and electrochemical impedance spectroscopy(EIS).The presence of HAsc in the conversion solution causes changes in the morphology,adherence and anticorrosive performance of the films.The improvement in the corrosion resistance is closely associated with the corrosion inhibition properties of HAsc. 展开更多
关键词 Cerium coatings AZ91D alloy ascorbic acid Anticorrosive properties
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Prevalence of Iron Deficiency and Iron Deficiency Anemia in Infants and Children and Treatment with Microencapsulated Iron II Fumarate and Supplied Ascorbic Acid as “Sprinkles” 被引量:4
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作者 Abdullah Al-Mamari Mohammad A. Al-Hegami +7 位作者 Sadeq Al-Hag Mahmoud Al-Buryhi Safa Al-Amawi Leena Ahmed Lila Al-Awadi Sarah Al-Jamal Wafa Mohammad Yasmin Mohammad 《Pharmacology & Pharmacy》 2014年第7期716-724,共9页
Background: Iron deficiency anemia (IDA) in children and infants is a common nutritional problem all over the world. Infants and young children have a high risk for developing iron deficiency (ID) because they have hi... Background: Iron deficiency anemia (IDA) in children and infants is a common nutritional problem all over the world. Infants and young children have a high risk for developing iron deficiency (ID) because they have high demand for iron during the period of rapid growth. This is aggravated by the insufficiency of iron in their diet. Iron supplementation programs using pediatric tablets or drops have not been successful in the control of anemia amongst infants and children in some countries. “Sprinkles” is an innovative multi-micronutrient home fortification strategy to control iron deficiency and anemia to be more useful. Objective: The objective was to estimate the prevalence ID and IDA in infants and children in Ibb City, Yemen Republic;evaluate the use of a new form of iron and determine the hematologic response to different doses and forms of iron in Sprinkles and iron drops. Design: Using a prospective, randomized, controlled design, we studied 337 randomly children aged 24 - 48 months and infants aged 6 - 24 months in Ibb City (hemoglobin: 70 - 99 g/L). One group received a daily sachet of microencapsulated ferrous fumarate (80 mg elemental Fe) in powder form plus ascorbic acid to be sprinkled onto any complementary food eaten (sprinkles group);a control group received ferrous sulfate drops 3 times/d for 2 months (total dose: 40 mg elemental Fe). Hemoglobin and serum ferritin concentrations were measured at baseline and at the end of treatment. Results: Successful treatment of anemia (hemoglobin > 100 g/L) occurred in 58% of the sprinkles group and in 56% of the drops group, with minimal side effects in both groups. Geometric mean ferritin concentrations increased significantly in each group from baseline to the end of treatment (P Conclusion: Use of ferrous sulfate drops or a single daily dose of microencapsulated ferrous fumarate sprinkles plus ascorbicacid resulted in a similar rate of successful treatment of anemia without side effects. To our knowledge, this is the first demonstration of the use of microencapsulated iron sprinkles to treat anemia in this area. Improved ease of use may favor the use of sprinkles to deliver iron. 展开更多
关键词 INFANTS Children ANEMIA Microencapsulated IRON ascorbic acid
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Low-volume plus ascorbic acid vs high-volume plus simethicone bowel preparation before colonoscopy 被引量:22
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作者 Stefano Pontone Rita Angelini +4 位作者 Monica Standoli Gregorio Patrizi Franco Culasso Paolo Pontone Adriano Redler 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第42期4689-4695,共7页
AIM:To investigate the effectiveness of low-volumeplus ascorbic acid [polyethylene glycol plus ascorbicacid(PEG + Asc) ] and high-volume plus simethicone[polyethylene glycol plus simethicone(PEG + Sim) ]bowel preparat... AIM:To investigate the effectiveness of low-volumeplus ascorbic acid [polyethylene glycol plus ascorbicacid(PEG + Asc) ] and high-volume plus simethicone[polyethylene glycol plus simethicone(PEG + Sim) ]bowel preparations.METHODS:A total of one hundred and forty-fourout patients(76 males) ,aged from 20 to 84 years(me-dian age 59.5 years) ,who attended our Department,were divided into two groups,age and sex matched,and underwent colonoscopy. Two questionnaires,onefor patients reporting acceptability and the other forendoscopists evaluating bowel cleansing effectivenes saccording to validated scales,were completed. Indications,timing of examination and endoscopical findings were recorded. Biopsy forceps were used as a measuring tool in order to determine polyp endoscopic sizeestimation. Difficulty in completing the preparation wasrated in a 5-point Likert scale(1 = easy to 5 = un-able) . Adverse experiences(fullness,cramps,nausea,vomiting,ab dominal pain,headache and insomnia) ,number of evacuations and types of activities performed during preparation(walking or resting in bed) were also investigated.RESULTS:Seventy-two patients were selected for eachgroup. The two groups were age and sex matched aswell as being comparable in terms of medical historyand drug therapies taken. Fourteen patients droppedout from the trial because they did not complete the preparation procedure. Ratings of global bowel cleansing examinations were considered to be adequate in91% of PEG + Asc and 88% of PEG + Sim patients.Residual Stool Score indicated similar levels of amountand consistency of residual stool;there was a significant difference in the percentage of bowel wall visuali-zation in favour of PEG + Sim patients. In the PEG +Sim group,12 adenomas ≤ 10 mm diameter(5/left co-lon + 7/right colon) vs 9(8/left colon + 1/right colon) in the PEG + Asc group were diagnosed. Visualization of small lesions seems to be one of the primary advantages of the PEG + Sim preparation.CONCLUSION:PEG + Asc is a good alternative solution as a bowel preparation but more improvements arenecessary in order to achieve the target of a perfect preparation. 展开更多
关键词 抗坏血酸 结肠镜 小批量 肠道 检查 聚乙二醇 平均年龄 音量
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