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Fulltext Effective jam preparations from watermelon waste

Souad, A.M., Jamal, P., Olorunnisola, K.S.

International Food Research Journal, 2012;19(4):1545-1549.
MyJurnal

Watermelon waste materials remained one of the important food grade agro-wastes generated by most hospitality industries in Southeast Asia and particularly in Malaysia. Jam was prepared from watermelon rind with different flavours (vanilla, pineapple, strawberry, lemon and no flavour). Five different samples were prepared at various compositions T₁ (50-50), T₂ (80-20), T₃ (60-40), T₄ (40-60) and T₅ (20-80) of rind and sugar. T₁ (50-50) gave the best jam set. Ten man panel (trained) evaluated the jam for its sensory characteristics and physicochemical analysis. Sensory evaluation conducted among five flavours was significantly different at (p>0.05). Chemical analysis showed that ascorbic acid reduced greatly among all treatments during three month storage. Soluble sugar and pH also decreased gradually for T₁ (from 4.96 to 4.40), T₂ (from 4.92 to 4.21), T₃ (from 4.74 to 4.11), T₄ (from 4.62 to 4.51) and T₅ (from 4.52 to 4.25) upon storage. Strawberry flavoured jam was most acceptable by the panel.

Matched MeSH terms: Ascorbic Acid
Fulltext Effect of heat and thermosonication on kinetics of peroxidase inactivation and vitamin C degradation in seedless guava (Psidium guajava L.)

Ali, G., Russly, A.R., Jamilah, B., Azizah, O., Mandana, B.

International Food Research Journal, 2011;18(4):1289-1294.
MyJurnal

This study aims to evaluate the effect of heat and the simultaneous application of heat (80-95°C) and ultrasonic waves (thermosonication) on the inactivation kinetic of peroxidase and vitamin C degradation in seedless guava. Ultrasonic wave’s amplitudes except 25 and 100% had significant (P 0.98). In the heat blanching process, the peroxidase inactivation rate constant increased from 1.1×10-2 to 4.6×10-2 s-1. However, the inactivation rate of peroxidase was increased by 1.5–3 times in the temperature range 80–95ºC, with the 50 and 75% ultrasonic wave amplitudes, respectively. Decreases in vitamin C contents due to blanching treatments were found. Blanching processes at high temperature and short time resulted in higher vitamin C retention. It was found that thermosonication treatment inactivates seedless guava peroxidase at less severe blanching conditions and consequently retains vitamin C content at higher levels. The present findings will help to design the blanching conditions in order to reduce the severity of conventional thermal treatments and, therefore, improving the quality of the thermally treated product.

Matched MeSH terms: Ascorbic Acid
Fulltext Extending ‘Kampuchea’ guava shelf-life at 27oC using 1-methylcyclopropene

Phebe, D., Ong, P.T.

International Food Research Journal, 2010;17(1):63-69.
MyJurnal

‘Kampuchea’ guavas were treated with 300, 600 and 900 nL L‾¹ 1-methylcyclopropene (1-MCP) for 0,
3 and 6 h, and stored at 27˚C with 70% relative humidity. The C* values, soluble solids concentration, titratable acidity and pH of these fruits were not affected by both the 1-MCP concentrations and exposure duration while h˚ values and flesh firmness were affected by these treatments. The L* values, vitamin C content and weight loss were affected by the concentrations of 1-MCP, but not by the exposure duration. Less weight loss and disease incidence in fruit treated with 600 and 900 nL L-1 1-MCP. Fruit exposed to 6 h 1-MCP showed lowest disease incidence compared to other exposure duration in 5 days of storage. Treating Kampuchea guava fruit with 600 nL L‾¹ 1-MCP and exposure duration of 6 h was able to retain fruit colour, flesh firmness and delayed disease development for 5 days.

Matched MeSH terms: Ascorbic Acid
Fulltext Inhibitory effect of onion extract on cassava leaf (Manihot esculenta Crantz) polyphenol oxidase

Wong, C. W., Angel Lee, P. L.

International Food Research Journal, 2014;21(2):755-758.
MyJurnal

The inhibitory effect of onion extract on cassava leaf polyphenol oxidase was investigated. The polyphenol oxidase from cassava leaves was strongly inhibited by various anti-browning agents such as L-ascorbic acid and L-cysteine. The percentage of inhibition increased with the increased of anti-browning agents concentrations. The addition of heated onion extract exhibited a stronger inhibitory effect on cassava leaf polyphenol oxidase than the fresh onion extract. The highest percentage of inhibition was exhibited with heated onion extract in the presence of glucose and glycine, which was 87.18%. The onion extract inhibited the cassava leaf polyphenol oxidase non-competitively.

Matched MeSH terms: Ascorbic Acid
The effect of ultraviolet treatment on enzymatic activity and total phenolic content of minimally processed potato slices

Teoh LS, Lasekan O, Adzahan NM, Hashim N

J Food Sci Technol, 2016 Jul;53(7):3035-3042.
PMID: 27765974

In this work, potato slices were exposed to different doses of UV-C irradiation (i.e. 2.28, 6.84, 11.41, and 13.68 kJ m(-2)) with or without pretreatment [i.e. ascorbic acid and calcium chloride (AACCl) dip] and stored at 4 ± 1 °C. Changes in enzymatic activities of polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonia lyase (PAL), as well as total phenolic content (TPC) were investigated after 0, 3, 7 and 10 days of storage. Results showed that untreated and UV-C treated potato slices at 13.68 kJ m(-2) dosage level showed significantly higher PPO, POD and PAL activities. Conversely, untreated potato slices showed the lowest TPC during storage period. Potato slices subjected to AACCl dip plus UV-C at 6.84 kJ m(-2) produced lower PPO, POD and PAL activities, as well as maintained a high TPC during storage.

Matched MeSH terms: Ascorbic Acid
Formation of high-density crystalline-shape gold nanoparticles on indium tin oxide surfaces: effects of alcohothermal seeding

Umar AA, Salleh MM, Majlis BY, Oyama M

J Nanosci Nanotechnol, 2011 Jun;11(6):4974-80.
PMID: 21770130

We found that the gold nanoparticles with high-density and crystalline-shape, such as nanocubes, nanobricks, pentahedral nanorods, etc., can be realized on the surface by using a seed-mediated growth method with a unique seeding process, namely alcohothermal. By using a conventional growth solution that contains HAuCl4, cetyltrimethylammonium bromide, NaOH and ascorbic acid, gold nanoparticles with crystalline-morphology (gold nanocrystals) of yield up to ca. 95%, can be prepared. An alcohothermal seeding was carried out by a thermal reduction of gold ions from an alcoholic solution of gold salt on the surface through an annealing process at a moderate temperature, namely 250 degrees C. It is believed that the unique initial characteristic (presumably the structures) of the gold nanoseeds particles as the result of peculiar nanoseeds formation process, prepared using this approach, instead of a simple thermal restructuring of the as prepared nanoseeds as confirmed by the results of annealing treatment on the nanoseed prepared using the normal and in-situ reduction seeding, was as the driving factor for the projected growth of crystalline-shape gold nanoparticles on the surface. The crystalline-shape gold nanoparticles modified-surface should find a potential application in catalysis, sensors and SERS.

Matched MeSH terms: Ascorbic Acid
Seedless okra pod, chlorophyll, vitamin C and mineral content development using plant growth regulator in vitro and in vivo culture

Hossain AS, Alenazi MMA, Ahmed ASA, Alrudayni HA, Haouala F, Al-Hashimi A, et al.

Cell Mol Biol (Noisy-le-grand), 2023 Dec 10;69(13):53-58.
PMID: 38158689 DOI: 10.14715/cmb/2023.69.13.8

Vegetables are rich in vitamins, minerals and dietary fiber that keep a significant role in the functioning of the human body to refrain human health benefits. The experiment was carried out to investigate the effect of different concentrations of IAA on the seedless pod, chlorophyll, vitamin and mineral content of okra as human health benefits. The innovative seed soaking method of application using 0, 25, 50, 100 & 200 mg/l of IAA concentrations was used in okra before germination and cultured in vitro and in vivo. The lower concentrations (25 and 50 mg/l) of IAA significantly increased the pod setting compared to the higher concentration (100 and 200 mg/l). The higher concentration (100 and 200 mg/l) had lower fruit settings than the lower concentration (25 &50) had higher fruit settings. The higher pod size was obtained in the concentration of 100 & 200 mg/l of IAA (34.18 cm²) as compared to the control and other concentrations. In addition, the highest soluble solid content was obtained by 100 and 200 mg/l of IAA concentration as compared to the other concentrations. The maximum vitamin C was found in the concentration of 100 mg/l of IAA as compared to the control and other concentrations. Moreover, higher mineral contents like K, Ca, Mg, Na and Fe were found in 100 & 200 mg/l of IAA. The higher concentrations (100 and 200 mg/l) of IAA greatly increased the seedless okra percentage as compared to the lower concentration. It seemed that 100 and 200 mg/l concentration IAA was a better concentration for mineral content and seedless okra production as compared to the other concentrations.

Matched MeSH terms: Ascorbic Acid
Fulltext Simultaneous time-temperature-thickness superposition theoretical and statistical modelling of convective drying of guava

Kek SP, Chin NL, Yusof YA

J Food Sci Technol, 2014 Dec;51(12):3609-22.
PMID: 25477628 DOI: 10.1007/s13197-013-0923-0

Modelling studies of guava drying and quality are presented using theoretical and statistical models by varying temperature from 55 to 75 °C and slice thickness from 3 to 9 mm. The quality of dried fruit was measured for its water activity, colour, vitamin C, and texture. The superposition technique with Midilli-Kucuk model showed efficiency in modelling the drying process with R (2) = 0.9991. The second-order polynomial equations adequately described the quality of dried guava with regression coefficient, R (2) > 0.7. Drying time was a good function of temperature and thickness (P

Matched MeSH terms: Ascorbic Acid
Fulltext Callus cell proliferation from broccoli leaf slice using IBA and BAP in vitro culture: Its biochemical and antioxidant properties

Sharif Hossain AB, Haq I, Ibrahim NA, Aleissa MS

Data Brief, 2016 Mar;6:214-20.
PMID: 26862562 DOI: 10.1016/j.dib.2015.11.061

Plant tissue or cell culture keeps a significant role in micro-propagation in the plant production industry. Combination of 6-Benzylaminopurine (BAP) and other plant growth regulators like 1-Naphthaleneacetic acid (NAA) or Indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) was used in the most of the research in tissue culture. The study was carried out to investigate the optimization of the concentration of IBA and BAP combination (0, 0.25, 0.50, 1.0, 1.50, 2.0, 2.5, 3.0 and 3.5 mg/l) for the root, callus and leaf proliferation from the leaf cutting slice. The highest number (6.75) of root proliferation was observed in the concentration of 2.0 mg/l IBA+0.25 mg/l BAP combination. The callus initiation was found in the concentration of IBA 1.0-3.5 mg/l+BAP 1.0-2.0 mg/l. However, the highest callus weight was observed at the concentration of IBA 1.5 mg/l+BAP 1.0 mg/l combination than other combination of concentrations. Positively leaf initiation and formation was better in the concentration of IBA 1-3.5 mg/l+BAP 1.0-2.0 mg/l combination. In addition, the 2,2-diphenyl-2-picrylhydarzyl (DPPH) free radical scavenging potential was higher (70.1%) in leaves extract than in callus extracts (46.3%) at the concentration of 10 mg/ml though both extracts had lower DPPH free radical scavenging activity compared to the positive control, vitamin C and BHT. Theresults conclude that the optimum concentration was IBA 1.5 mg/l+BAP 1.0 mg/l combination to produce callus cell proliferation and concentration of 2.0 mg/l IBA+0.25 mg/l BAP combination was the optimum for root proliferation of broccoli in vitro.

Matched MeSH terms: Ascorbic Acid
Fulltext Comparative Analysis of Antioxidant Compounds and Antioxidative Properties of Thai Indigenous Rice: Effects of Rice Variety and Processing Condition

Summpunn P, Panpipat W, Manurakchinakorn S, Bhoopong P, Cheong LZ, Chaijan M

Molecules, 2022 Aug 14;27(16).
PMID: 36014418 DOI: 10.3390/molecules27165180

Indigenous southern Thai non-glutinous rice varieties Kaab Dum, Khai Mod Rin, Yar Ko, Yoom Noon, and Look Lai made under four different processing conditions, white rice, brown rice, germinated brown rice, and rice grass, were assessed for antioxidant components and in vitro antioxidative activities. According to the findings, rice’s antioxidant components and antioxidant activity were considerably impacted by both variety and processing. High levels of total extractable phenolic compounds (164−314 mg gallic acid equivalent (GAE)/kg, dry weight (dw)) and carotenoid (0.92−8.65 mg/100 g, dw) were found in all rice varieties, especially in rice grass and germinated brown rice, indicating that milling to generate white rice had an adverse effect on those components. Additionally, after germination, a higher γ-oryzanol concentration (9−14 mg/100 g, dw) was found. All rice varieties had higher ascorbic acid, phenolic compound, and carotenoid contents after sprouting. Overall, Yoom Noon rice grass had the highest total extractable phenolic content (p < 0.05). The rice grass from Yoom Noon/Look Lai/Kaab Dum had the highest ascorbic acid content (p < 0.05). The total carotenoid concentration of Look Lai rice grass was the highest, and Yoom Noon’s germinated brown rice had the highest γ-oryzanol content (p < 0.05). All rice varieties’ aqueous extracts had remarkable ABTS free radical scavenging activity, with Khai Mod Rin reaching the highest maximum value of 42.56 mmol Trolox equivalent/kg dw. Other antioxidant mechanisms, however, were quite low. Compared to germinated brown rice, brown rice, and white rice, rice grass often tended to have stronger antioxidant activity. Yar Ko rice grass was found to have the highest DPPH free radical scavenging activity (3.8 mmol Trolox equivalent/kg dw) and ferric reducing antioxidant power (FRAP) (4.6 mmol Trolox equivalent/kg dw) (p < 0.05). Khai Mod Rice grass had the most pronounced metal chelation activity (1.14 mmol EDTA equivalent/kg dw) (p < 0.05). The rice variety and processing conditions, therefore, influenced the antioxidant compounds and antioxidative properties of Thai indigenous rice. The results can be used as a guide to select the optimal rice variety and primary processing in order to satisfy the needs of farmers who want to produce rice as a functional ingredient and to promote the consumption of indigenous rice by health-conscious consumers.

Matched MeSH terms: Ascorbic Acid
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*
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*
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*
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*
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*
Fulltext Diet and cancer

Med J Malaysia, 1988 Dec;43(4):348-9.
PMID: 2853823
Matched MeSH terms: Ascorbic Acid/adverse effects
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*
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*
Fulltext The influence of operational parameters and feed preparation in a convective batch ribbon powder mixer

Yeow ST, Shahar A, Abdul Aziz N, Anuar MS, Yusof YA, Taip FS

Drug Des Devel Ther, 2011;5:465-9.
PMID: 22162640 DOI: 10.2147/DDDT.S25047

To investigate the effect of feed preparation characteristics and operational parameters on mixing homogeneity in a convective batch ribbon mixer.

Matched MeSH terms: Ascorbic Acid/chemistry
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

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