Displaying publications 61 - 80 of 211 in total

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  1. Plasma vitamin C and tocotrienols changes in response to dietary supplementation among young male adults
    Zahara AM, Lee CC, Fatimah IS, Poh BK, Khairul O, Das S, et al.
    Clin Ter, 2010;161(2):121-4.
    PMID: 20499024
    Intake of the antioxidant vitamins C and E lowers the oxidative stress. The study aimed to determine plasma concentrations of vitamin C and tocotrienols after supplementation of both vitamins in young male adults.
    Matched MeSH terms: Ascorbic Acid/blood*
  2. Fulltext Copper nanoparticles mediated by chitosan: synthesis and characterization via chemical methods
    Usman MS, Ibrahim NA, Shameli K, Zainuddin N, Yunus WM
    Molecules, 2012 Dec 14;17(12):14928-36.
    PMID: 23242252 DOI: 10.3390/molecules171214928
    Herein we report a synthesis of copper nanoparticles (Cu-NPs) in chitosan (Cts) media via a chemical reaction method. The nanoparticles were synthesized in an aqueous solution in the presence of Cts as stabilizer and CuSO(4)·5H(2)O precursor. The synthesis proceeded with addition of NaOH as pH moderator, ascorbic acid as antioxidant and hydrazine( )as the reducing agent. The characterization of the prepared NPs was done using ultraviolet-visible spectroscopy, which showed a 593 nm copper band. The Field Emission Scanning Electron Microscope (FESEM) images were also observed, and found to be in agreement with the UV-Vis result, confirming the formation of metallic Cu-NPs. The mean size of the Cu-NPs was estimated to be in the range of 35-75 nm using X-ray diffraction. XRD was also used in analysis of the crystal structure of the NPs. The interaction between the chitosan and the synthesized NPs was studied using Fourier transform infrared (FT-IR) spectroscopy, which showed the capping of the NPs by Cts.
    Matched MeSH terms: Ascorbic Acid/chemistry
  3. Sensitive voltammetric determination of paracetamol by poly (4-vinylpyridine)/multiwalled carbon nanotubes modified glassy carbon electrode
    Ghadimi H, Tehrani RM, Ali AS, Mohamed N, Ab Ghani S
    Anal Chim Acta, 2013 Feb 26;765:70-6.
    PMID: 23410628 DOI: 10.1016/j.aca.2012.12.039
    A novel glassy carbon electrode (GCE) modified with a composite film of poly (4-vinylpyridine) (P4VP) and multiwalled carbon nanotubes (P4VP/MWCNT GCE) was used for the voltammetric determination of paracetamol (PCT). This novel electrode displayed a combined effect of P4VP and MWCNT on the electro-oxidation of PCT in a solution of phosphate buffer at pH 7. Hence, conducting properties of P4VP along with the remarkable physical properties of MWCNTs might have combined effects in enhancing the kinetics of PCT oxidation. The P4VP/MWCNT GCE has also demonstrated excellent electrochemical activity toward PCT oxidation compared to that with bare GCE and MWCNT GCE. The anodic peak currents of PCT on the P4VP/MWCNT GCE were about 300 fold higher than that of the non-modified electrodes. By applying differential pulse voltammetry technique under optimized experimental conditions, a good linear ratio of oxidation peak currents and concentrations of PCT over the range of 0.02-450 μM with a limit of detection of 1.69 nM were achieved. This novel electrode was stable for more than 60 days and reproducible responses were obtained at 99% of the initial current of PCT without any influence of physiologically common interferences such as ascorbic acid and uric acid. The application of this electrode to determine PCT in tablets and urine samples was proposed.
    Matched MeSH terms: Ascorbic Acid/chemistry
  4. A unique "turn-on" fluorescence signalling strategy for highly specific detection of ascorbic acid using carbon dots as sensing probe
    Fong JFY, Chin SF, Ng SM
    Biosens Bioelectron, 2016 Nov 15;85:844-852.
    PMID: 27290666 DOI: 10.1016/j.bios.2016.05.087
    Carbon dots (CDs) that showed strong blue fluorescence were successfully synthesised from sodium alginate via furnace pyrolysis. The single step pyrolytic synthesis was simple to perform while yielded CDs with high photostability, good water solubility and minimum by-products. In order to design the probe with "turn-on" sensing capability, the CDs were screened against a series of metal cations to first "turn-off" the fluorescence. It was found that ferric ions (Fe(3+)) were most responsive and effective in quenching the fluorescence of CDs. Based on this observation, the conditioning of the probe was performed to ensure the fluorescence was completely quenched, while not overloading the system with Fe(3+). At the optimised condition, the CDs-Fe(3+) mixture served as a highly specific detection probe for ascorbic acid (AA). The analytical potential of the probe was evaluated and showed a good linear range of response for AA concentration of 24-40μg/mL. The selectivity study against other possible co-existing species was carried out and proved that our unique "turn-on" fluorescence signalling strategy was highly effective and selective towards AA as the target analyte. The probe was demonstrated for quantification of AA in real samples, which was the commercially available vitamin C supplement. The result showed good accuracy with minimum deviation from standard method adopted for validation purpose.
    Matched MeSH terms: Ascorbic Acid/analysis*
  5. Fulltext Diet and cancer
    Med J Malaysia, 1988 Dec;43(4):348-9.
    PMID: 2853823
    Matched MeSH terms: Ascorbic Acid/adverse effects
  6. Obesity, cardiovascular disease, and role of vitamin C on inflammation: a review of facts and underlying mechanisms
    Ellulu MS
    Inflammopharmacology, 2017 Jun;25(3):313-328.
    PMID: 28168552 DOI: 10.1007/s10787-017-0314-7
    Obesity means the accumulation of excessive fat that may interfere with the maintenance of optimal state of health. Obesity causes cardiac and vascular disease through well-known mediators such as hypertension, type-2 diabetes mellitus, and dyslipidemia, but there are evidences for other mediators such as chronic inflammation, oxidative stress, and thrombosis. The decreased levels of antioxidants factors and nitric oxide predispose to further cardiovascular adverse events. To reduce the risks, antioxidants can help by neutralizing the free radicals and protecting from damage by donating electrons. Having the capacity, vitamin C protects from oxidative stress, prevention of non-enzymatic glycosylation of proteins, and enhances arterial dilation through its effect on nitric oxide release. It also decreases lipid peroxidation, and alleviates inflammation. The anti-inflammatory property of vitamin C could be attributed to ability to modulate the NF-kB DNA binding activity and down-regulation in the hepatic mRNA expression for the interleukins and tumor factors.
    Matched MeSH terms: Ascorbic Acid/pharmacology*
  7. Fulltext Vitamin C: A Review on its Role in the Management of Metabolic Syndrome
    Wong SK, Chin KY, Ima-Nirwana S
    Int J Med Sci, 2020;17(11):1625-1638.
    PMID: 32669965 DOI: 10.7150/ijms.47103
    Oxidative stress and inflammation are two interlinked events that exist simultaneously in metabolic syndrome (MetS) and its related complications. These pathophysiological processes can be easily triggered by each other. This review summarizes the current evidence from animal and human studies on the effects of vitamin C in managing MetS. In vivo studies showed promising effects of vitamin C, but most of the interventions used were in combination with other compounds. The direct effects of vitamin C remain to be elucidated. In humans, the current state of evidence revealed that lower vitamin C intake and circulating concentration were found in MetS subjects. A negative relationship was observed between vitamin C intake / concentration and the risk of MetS. Oral supplementation of vitamin C also improved MetS conditions. It has been postulated that the positive outcomes of vitamin C may be in part mediated through its anti-oxidative and anti-inflammatory properties. These observations suggest the importance of MetS patients to have an adequate intake of vitamin C through food, beverages or supplements in order to maintain its concentration in the systemic circulation and potentially reverse MetS.
    Matched MeSH terms: Ascorbic Acid/therapeutic use*
  8. Anthraquinones production, hydrogen peroxide level and antioxidant vitamins in Morinda elliptica cell suspension cultures from intermediary and production medium strategies
    Chong TM, Abdullah MA, Fadzillah NM, Lai OM, Lajis NH
    Plant Cell Rep, 2004 Jul;22(12):951-8.
    PMID: 15067428
    The effects of medium strategies [maintenance (M), intermediary (G), and production (P) medium] on cell growth, anthraquinone (AQ) production, hydrogen peroxide (H2O2) level, lipid peroxidation, and antioxidant vitamins in Morinda elliptica cell suspension cultures were investigated. These were compared with third-stage leaf and 1-month-old callus culture. With P medium strategy, cell growth at 49 g l(-1), intracellular AQ content at 42 mg g(-1) DW, and H2O2 level at 9 micromol g(-1) FW medium were the highest as compared to the others. However, the extent of lipid peroxidation at 40.4 nmol g(-1) FW and total carotenoids at 13.3 mg g(-1) FW for cultures in P medium were comparable to that in the leaf, which had registered sevenfold lower AQ and 2.2-fold lower H2O2 levels. Vitamin C content at 30-120 microg g(-1) FW in all culture systems was almost half the leaf content. On the other hand, vitamin E content was around 400-500 microg g(-1) FW in 7-day-old cultures from all medium strategies and reduced to 50-150 microg g(-1) FW on day 14 and 21; as compared to 60 microg g(-1) FW in callus and 200 microg g(-1) FW in the leaf. This study suggests that medium strategies and cell growth phase in cell culture could influence the competition between primary and secondary metabolism, oxidative stresses and antioxidative measures. When compared with the leaf metabolism, these activities are dynamic depending on the types and availability of antioxidants.
    Matched MeSH terms: Ascorbic Acid/metabolism*
  9. Fabrication of low-cost sustainable electrocatalyst: a diagnostic tool for multifunctional disorders in human fluids
    Sinduja B, Gowthaman NSK, John SA
    J Mater Chem B, 2020 10 28;8(41):9502-9511.
    PMID: 32996975 DOI: 10.1039/d0tb01681k
    In purine metabolism, the xanthine oxidoreductase enzyme converts hypoxanthine (HXN) to xanthine (XN) and XN to uric acid (UA). This leads to the deposition of UA crystals in several parts of the body and the serum UA level might be associated with various multifunctional disorders. The dietary intake of caffeine (CF) and ascorbic acid (AA) decreases the UA level in the serum, which leads to cellular damage. Hence, it is highly needed to monitor the UA level in the presence of AA, XN, HXN, and CF and vice versa. Considering this sequence of complications, the present paper reports the fabrication of an electrochemical sensor using low-cost N-doped carbon dots (CDs) for the selective and simultaneous determination of UA in the presence of AA, XN, HXN, and CF at the physiological pH. The colloidal solution of CDs was prepared by the pyrolysis of asparagine and fabricated on a GC electrode by cycling the potential from -0.20 to +1.2 V in a solution containing CDs and 0.01 M H2SO4. Here, the surface -NH2 functionalities of CDs were used to make a thin film of CDs on the GC electrode. FT-IR spectroscopy confirmed the involvement of the -NH2 group in the formation of the CD film. HR-TEM analysis depicts that the formed CDs showed spherical particles with a size of 1.67 nm and SEM analysis exhibits the 89 nm CD film on the GC electrode surface. The fabricated CD film was successfully used for the sensitive and selective determination of UA. The determination of UA was achieved selectively in a mixture consisting of AA, XN, HXN, and CF with 50-fold high concentration. The CDs-film fabricated electrode has several benefits over the bare electrode: (i) well-resolved oxidation peaks for five analytes, (ii) boosted sensitivity, (iii) shifted oxidation as well as on-set potentials toward less positive potentials, and (iv) high stability. The practical utility of the present sensor was tested by simultaneously determining the multifactorial disorders-causing agents in human fluids. The electrocatalyst developed in the present study is sustainable and can be used for multiple analyses; besides, the electrochemical method used for the fabrication of the CD film is environmentally benign.
    Matched MeSH terms: Ascorbic Acid/blood*
  10. Fulltext Effects of cysteine and ascorbic acid in freezing extender on sperm characteristics and level of enzymes in post-thawed stallion semen
    Alamaary MS, Haron AW, Hiew MWH, Ali M
    Vet Med Sci, 2020 11;6(4):666-672.
    PMID: 32602662 DOI: 10.1002/vms3.315
    Present study aimed to investigate the effect of adding antioxidants, cysteine and ascorbic acid on the levels of glutamic oxaloacetic transaminase (GOT), glutamic-pyruvate (GPT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and γ-glutamyl transpeptidase (GGT) enzymes of post-thawed stallion sperm. Ten ejaculates were collected each from four healthy stallions and cryopreserved using HF-20 freezing extender containing either 0 mg/ml cysteine or ascorbic acid, 0.5 mg/ml cysteine and 0.5 mg/ml ascorbic acid. All samples in freezing extender containing cysteine or ascorbic acid or none of them were assessed for sperm motility, viability, plasma membrane integrity, morphology and enzymes concentration. The ALP, LDH and GGT were significantly higher in 0-group compared with cysteine and ascorbic acid groups. The sperm motility of frozen-thawed semen with 0-group was significantly better compared with cysteine and ascorbic acid groups. The variation on viability, sperm membrane integrity and morphology were insignificant between all treated groups. Therefore, these enzymes were reduced when using antioxidants in the freezing extender. Results of the present study suggest that concentration of ALP, LDH and GGT enzymes could be used as parameters for prediction of frozen-thawed stallion semen.
    Matched MeSH terms: Ascorbic Acid/pharmacology*
  11. The ameliorative effect of ascorbic acid on the oxidative status, live weight and recovery rate in road transport stressed goats in a hot humid tropical environment
    Nwunuji TP, Mayowa OO, Yusoff SM, Bejo SK, Salisi S, Mohd EA
    Anim Sci J, 2014 May;85(5):611-6.
    PMID: 24612236 DOI: 10.1111/asj.12174
    The ameliorative effect of ascorbic acid (AA) on live weight following transportation is vital in animal husbandry. This study investigated the influence of AA on live weight, rectal temperature (rt), and oxidative status of transport stressed goats in a hot humid tropical environment. Twenty-four goats were divided into four groups, A, B, C and D of six animals each. Group A were administered AA 100 mg/kg intramuscularly 30 min prior to 3.5 h transportation. Group B was administered AA following transportation. Group C were transported but not administered AA as positive controls while group D were not transported but were administered normal saline as negative controls. Live weight, rt and blood samples were collected before, immediately post-transport (pt), 24 h, 3 days, 7 days and 10 days pt. Plasma was used for malondialdehyde (MDA) analysis while hemolysates were used for superoxide dismutase (SOD) analysis. There was minimal live weight loss in group A compared to groups B and C. Group A recorded reduced MDA activities and increased SOD activities compared to groups B and C which recorded significantly high MDA activities. This study revealed that AA administration ameliorated the stress responses induced by transportation in animals in hot humid tropical environments. The administration of AA to goats prior to transportation could ameliorate stress and enhance productivity.
    Matched MeSH terms: Ascorbic Acid/pharmacology*
  12. Simultaneous determination of ascorbic acid, dopamine and uric acid by a novel electrochemical sensor based on N2/Ar RF plasma assisted graphene nanosheets/graphene nanoribbons
    Jothi L, Neogi S, Jaganathan SK, Nageswaran G
    Biosens Bioelectron, 2018 May 15;105:236-242.
    PMID: 29412948 DOI: 10.1016/j.bios.2018.01.040
    A novel nitrogen/argon (N2/Ar) radio frequency (RF) plasma functionalized graphene nanosheet/graphene nanoribbon (GS/GNR) hybrid material (N2/Ar/GS/GNR) was developed for simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Various nitrogen mites introduced into GS/GNR hybrid structure was evidenced by a detailed microscopic, spectroscopic and surface area analysis. Owing to the unique structure and properties originating from the enhanced surface area, nitrogen functional groups and defects introduced on both the basal and edges, N2/Ar/GS/GNR/GCE showed high electrocatalytic activity for the electrochemical oxidations of AA, DA, and UA with the respective lowest detection limits of 5.3, 2.5 and 5.7 nM and peak-to-peak separation potential (ΔEP) (vs Ag/AgCl) in DPV of 220, 152 and 372 mV for AA/DA, DA/UA and AA/UA respectively. Moreover, the selectivity, stability, repeatability and excellent performance in real time application of the fabricated N2/Ar/GS/GNR/GCE electrode suggests that it can be considered as a potential electrode material for simultaneous detection of AA, DA, and UA.
    Matched MeSH terms: Ascorbic Acid/blood*
  13. IV Vitamin C in Critically Ill Patients: A Systematic Review and Meta-Analysis
    Patel JJ, Ortiz-Reyes A, Dhaliwal R, Clarke J, Hill A, Stoppe C, et al.
    Crit Care Med, 2022 Mar 01;50(3):e304-e312.
    PMID: 34637420 DOI: 10.1097/CCM.0000000000005320
    OBJECTIVES: To conduct a systematic review and meta-analysis to evaluate the impact of IV vitamin C on outcomes in critically ill patients.

    DATA SOURCES: Systematic search of MEDLINE, EMBASE, CINAHL, and the Cochrane Register of Controlled Trials.

    STUDY SELECTION: Randomized controlled trials testing IV vitamin C in critically ill patients.

    DATA ABSTRACTION: Two independent reviewers abstracted patient characteristics, treatment details, and clinical outcomes.

    DATA SYNTHESIS: Fifteen studies involving 2,490 patients were identified. Compared with placebo, IV vitamin C administration is associated with a trend toward reduced overall mortality (relative risk, 0.87; 95% CI, 0.75-1.00; p = 0.06; test for heterogeneity I2 = 6%). High-dose IV vitamin C was associated with a significant reduction in overall mortality (relative risk, 0.70; 95% CI, 0.52-0.96; p = 0.03), whereas low-dose IV vitamin C had no effect (relative risk, 0.94; 95% CI, 0.79-1.07; p = 0.46; test for subgroup differences, p = 0.14). IV vitamin C monotherapy was associated with a significant reduction in overall mortality (relative risk, 0.64; 95% CI, 0.49-0.83; p = 0.006), whereas there was no effect with IV vitamin C combined therapy. No trial reported an increase in adverse events related to IV vitamin C.

    CONCLUSIONS: IV vitamin C administration appears safe and may be associated with a trend toward reduction in overall mortality. High-dose IV vitamin C monotherapy may be associated with improved overall mortality, and further randomized controlled trials are warranted.

    Matched MeSH terms: Ascorbic Acid/therapeutic use*
  14. Fulltext Compositional variation in sugars and organic acids at different maturity stages in selected small fruits from pakistan
    Mahmood T, Anwar F, Abbas M, Boyce MC, Saari N
    Int J Mol Sci, 2012;13(2):1380-1392.
    PMID: 22408396 DOI: 10.3390/ijms13021380
    Selected soluble sugars and organic acids were analyzed in strawberry, sweet cherry, and mulberry fruits at different ripening stages by HPLC. The amounts of fructose, glucose and sucrose were found to be: strawberry (1.79-2.86, 1.79-2.25 and 0.01-0.25 g/100 g FW), sweet cherry (0.76-2.35, 0.22-3.39 and 0.03-0.13 g/100 g) and mulberry (3.07-9.41, 1.53-4.95 and 0.01-0.25 g/100 g) at un-ripened to fully-ripened stages, respectively. The strawberry, sweet cherry and mulberry mainly contained tartaric, citric and ascorbic acids in the range of 16-55, 70-1934 and 11-132 mg/100 g; 2-8, 2-10 and 10-17 mg/100 g; 2-118, 139-987 and 2-305 mg/100 g at un-ripened to fully-ripened stages, respectively. Fructose and glucose were established to be the major sugars in all the tested fruit while citric and ascorbic acid were the predominant organic acids in strawberry and mulberry while tartaric acid was mainly present in sweet cherry. The tested fruits mostly showed an increase in the concentration of sugars and organic acids with ripening.
    Matched MeSH terms: Ascorbic Acid/analysis*
  15. Fulltext Coumarins as Potential Antioxidant Agents Complemented with Suggested Mechanisms and Approved by Molecular Modeling Studies
    Al-Majedy YK, Al-Duhaidahawi DL, Al-Azawi KF, Al-Amiery AA, Kadhum AA, Mohamad AB
    Molecules, 2016 Jan 23;21(2):135.
    PMID: 26805811 DOI: 10.3390/molecules21020135
    Syntheses of coumarins, which are a structurally interesting antioxidant activity, was done in this article. The modification of 7-hydroxycoumarin by different reaction steps was done to yield target compounds. Molecular structures were characterized by different spectroscopical techniques (Fourier transformation infrared and nuclear magnetic resonance). Antioxidant activities were performed by using various in vitro spectrophometric assays against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydrogen peroxide (H2O2). All compounds exhibited high efficiency as antioxidants compared to ascorbic acid. The highest efficiency scavenging activity was found for compound 3 (91.0 ± 5.0), followed by compounds 2 and 4 (88.0 ± 2.00; and 87.0 ± 3.00). Ascorbic acid C was used as a standard drug with a percentage inhibition of 91.00 ± 1.5. The mechanism of the synthesized compounds as antioxidants was also studied. Hartree-Fock-based quantum chemical studies have been carried out with the basis set to 3-21G, in order to obtain information about the three-dimensional (3D) geometries, electronic structure, molecular modeling, and electronic levels, namely HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital), to understand the antioxidant activity for the synthesized compounds.
    Matched MeSH terms: Ascorbic Acid/pharmacology
  16. Effect of type and concentration of antioxidant on sperm motility, viability, and DNA integrity of climbing perch Anabas testudineus Bloch, 1792 (Pisces: Anabantidae) post-cryopreservation
    Maulida S, Eriani K, Fadli N, Siti-Azizah MN, Kocabas FK, Kocabas M, et al.
    Cryobiology, 2024 Mar;114:104851.
    PMID: 38237749 DOI: 10.1016/j.cryobiol.2024.104851
    Sperm quality is preserved through the crucial involvement of antioxidants, which play a vital role in minimizing the occurrence of reactive oxygen species (ROS) during the cryopreservation process. The suitability of the type and concentration of antioxidants are species-dependent, and this study is crucial in order to improve the quality of the climbing perch sperm post-cryopreservation. Therefore, this study aimed to determine the best type and concentration of antioxidants for cryopreservation of climbing perch Anabas testudineus sperm. To achieve this, 6 types of antioxidants, namely, ascorbic acid, beta-carotene, glutathione, butylated hydroxytoluene (BHT), myo-inositol, and alpha-tocopherol, with inclusion of a control were tested in 3 replications at three concentration levels of 0 mg/L (control), 20 mg/L, 40 mg/L, and 60 mg/L. Sperm was diluted in a glucose-base extender at a ratio of 1:60 (sperm: glucose base), then 10 % DMSO and 5 % egg yolk was added before cryopreservation for two weeks. The results showed that the type and concentration of antioxidants had a significant effect on the motility and viability of cryopreserved climbing perch sperm (P acid, beta-carotene, glutathione, myo-inositol, and alpha-tocopherol were obtained at a concentration of 60 mg/L, while BHT was at a concentration of 20 mg/L. The best results for glutathione, myo-inositol, and alpha-tocopherol were significantly different from other treatments, while the best results for ascorbic acid and beta-carotene (60 mg/L) were not significantly different from the 40 mg/L concentration, while the best results for BHT were not significantly different from the control treatments. Therefore, the best concentration of glutathione, myo-inositol, and alpha-tocopherol was 60 mg/L, while for ascorbic acid and beta-carotene it was 40 mg/L, and BHT was not recommended. DNA integrity analysis indicated the absence of fragmentation in all samples, including fresh, control, and treated sperm. Based on practical and economic considerations, myo-inositol at 60 mg/L was recommended for cryopreservation of climbing perch A. testudineus sperm.
    Matched MeSH terms: Ascorbic Acid/pharmacology
  17. Fulltext Effects of 1-methylcyclopropene and modified atmosphere packaging on the antioxidant capacity in pepper "Kulai" during low-temperature storage
    Tan CK, Ali ZM, Ismail I, Zainal Z
    ScientificWorldJournal, 2012;2012:474801.
    PMID: 22919322 DOI: 10.1100/2012/474801
    The objective of the present study was to simultaneously evaluate the effect of a postharvest treatment on the pepper's antioxidant content and its ability to retain its economical value during the postharvest period. The fruits were pretreated by modified atmosphere packaging (MAP) with or without treatment with 1-methylcyclopropene (1-MCP) before cold storage at 10°C. Changes in the levels of non-enzymatic antioxidants, including the total phenolic, ascorbic acid levels and the total glutathione level, as well as enzymatic antioxidants, including ascorbate peroxidase (APX), glutathione reductase (GR), and catalase (CAT), were determined. Both treatments successfully extended the shelf life of the fruit for up to 25 days, and a high level of antioxidant capacity was maintained throughout the storage period. However, 1-MCP treatment maintained the high antioxidant capacity for a longer period of time. The 1-MCP-treated peppers maintained high levels of phenolic content, a high reduced glutathione (GSH)/oxidised glutathione (GSSG) ratio, decreased levels of ascorbic acid and CAT activity, and increased levels of APX and GR compared with the peppers that were not treated with 1-MCP. The overall results suggested that a combination of 1-MCP and MAP was the most effective treatment for extending shelf life while retaining the nutritional benefits.
    Matched MeSH terms: Ascorbic Acid/metabolism
  18. Modified Hank's Balanced Salt Solution as a Storage Medium for Avulsed Teeth: In Vitro Assessment of Periodontal Fibroblast Viability
    Lee ZJ, Ng SL, Soo E, Abdullah D, Yazid F, Abdul Rahman M, et al.
    Dent Traumatol, 2025 Apr;41(2):194-202.
    PMID: 39578673 DOI: 10.1111/edt.13010
    BACKGROUND/AIM: The optimal storage medium for an avulsed tooth should preserve the viability of periodontal fibroblasts (PDLF) to the highest degree, facilitating the re-attachment of periodontal fibers and improving the prognosis of replantation. This study compared the effect of the PDLF viability in Hank's balanced salt solution (HBSS), supplemented culture medium, that is, Dulbecco's Modified Eagle Medium (DMEM), and four modified HBSS mixtures.

    MATERIAL AND METHODS: Periodontal tissues were obtained from extracted human teeth and processed for PDLF culture. The cells were then exposed to six experimental media: (i) HBSS, (ii) HBSS and ascorbic acid (HBSS + Vit C), (iii) HBSS and platelet-derived growth factor (HBSS + PDGF), (iv) a mixture of HBSS, PDGF, and Vit C (HBSS + PDGF + Vit C), (v) HBSS and platelet lysate (HBSS + PL), and (vi) DMEM for 3, 6, 12, and 24 h. A MTT assay was performed to determine the cell viability.

    RESULTS: Vitamin C-containing media maintained PDLF viability significantly better than HBSS + PDGF and HBSS + PL at 3, 6, 12, and 24 h (p HBSS+Vit C; HBSS+PDGF+Vit C>HBSS+PL>HBSS+PDGF; HBSS). Although DMEM had the highest cell proliferative effect, it is impractical to be used as a transport medium due to its cost, storage, and availability. The supplementation of Vit C yielded significant cell proliferative effects; hence, HBSS + Vit C can be a better alternative as a storage medium than HBSS.

    Matched MeSH terms: Ascorbic Acid/pharmacology
  19. Fulltext Involvement of nitrogen on flavonoids, glutathione, anthocyanin, ascorbic acid and antioxidant activities of Malaysian medicinal plant Labisia pumila Blume (Kacip Fatimah)
    Ibrahim MH, Jaafar HZ, Rahmat A, Rahman ZA
    Int J Mol Sci, 2012;13(1):393-408.
    PMID: 22312260 DOI: 10.3390/ijms13010393
    A split plot 3 by 4 experiment was designed to characterize the relationship between production of gluthatione (GSH), oxidized gluthatione (GSSG), total flavonoid, anthocyanin, ascorbic acid and antioxidant activities (FRAP and DPPH) in three varieties of Labisia pumila Blume, namely the varieties alata, pumila and lanceolata, under four levels of nitrogen fertilization (0, 90, 180 and 270 kg N/ha) for 15 weeks. The treatment effects were solely contributed by nitrogen application; there was neither varietal nor interaction effects observed. As the nitrogen levels decreased from 270 to 0 kg N/ha, the production of GSH and GSSG, anthocyanin, total flavonoid and ascorbic acid increased steadily. At the highest nitrogen treatment level, L. pumila exhibited significantly lower antioxidant activities (DPPH and FRAP) than those exposed to limited nitrogen growing conditions. Significant positive correlation was obtained between antioxidant activities (DPPH and FRAP), total flavonoid, GSH, GSSG, anthocyanin and ascorbic acid suggesting that an increase in the antioxidative activities in L. pumila under low nitrogen fertilization could be attributed to higher contents of these compounds. From this observation, it could be concluded that in order to avoid negative effects on the quality of L. pumila, it is advisable to avoid excessive application of nitrogen fertilizer when cultivating the herb for its medicinal use.
    Matched MeSH terms: Ascorbic Acid/analysis; Ascorbic Acid/chemistry*
  20. Fulltext What are the antioxidant status predictors' factors among male chronic obstructive pulmonary disease (COPD) patients?
    Pirabbasi E, Najafiyan M, Cheraghi M, Shahar S, Abdul Manaf Z, Rajab N, et al.
    Glob J Health Sci, 2013 Jan;5(1):70-8.
    PMID: 23283038 DOI: 10.5539/gjhs.v5n1p70
    Imbalance between antioxidant and oxidative stress is a major risk factor for pathogenesis of some chronic diseases such as chronic obstructive pulmonary disease (COPD). This study aimed to determine antioxidant and oxidative stress status, and also theirs association with respiratory function of male COPD patients to find the antioxidant predictors' factors. A total of 149 subjects were involved in a cross-sectional study. The study was conducted at two medical centers in Kuala Lumpur, Malaysia. Results of the study showed that plasma vitamin C was low in most of the subjects (86.6%). Total antioxidant capacity was the lowest in COPD stage IV compare to other stages (p < 0.05). Level of plasma vitamin A (p= 0.012) and vitamin C (p= 0.007) were low in malnourished subjects. The predictors for total antioxidant capacity were forced vital capacity (FVC) % predicted and intake of ?-carotene (R2= 0.104, p= 0.002). Number of cigarette (pack/ year) and smoking index (number/ year) were not associated with total antioxidant capacity of this COPD population. Plasma oxidative stress as assessed plasma lipid peroxidation (LPO) was only positively correlated with plasma glutathione (p= 0.002). It might be a need to evaluate antioxidant status especially in older COPD patients to treat antioxidant deficiency which is leading to prevent COPD progression.
    Study site: Outpatient clinics, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM) and Institute of Respiratory Medicine, Kuala Lumpur, Malaysia
    Matched MeSH terms: Ascorbic Acid/blood; Ascorbic Acid/physiology
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