Artigos de revistas: "Vitamin C loss"

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Zhu, Ling-Ling, Jay Cao, Merry Sun, Tony Yuen, Raymond Zhou, Jianhua Li, Yuanzhen Peng et al. "Vitamin C Prevents Hypogonadal Bone Loss". PLoS ONE 7, n.º 10 (8 de outubro de 2012): e47058. http://dx.doi.org/10.1371/journal.pone.0047058.

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Curhan, Sharon G., Konstantina M. Stankovic, Roland D. Eavey, Molin Wang, Meir J. Stampfer e Gary C. Curhan. "Carotenoids, vitamin A, vitamin C, vitamin E, and folate and risk of self-reported hearing loss in women". American Journal of Clinical Nutrition 102, n.º 5 (9 de setembro de 2015): 1167–75. http://dx.doi.org/10.3945/ajcn.115.109314.

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ABSTRACT Background: Higher intake of certain vitamins may protect against cochlear damage from vascular compromise and oxidative stress, thereby reducing risk of acquired hearing loss, but data are limited. Objective: We prospectively examined the relation between carotenoids, vitamin A, vitamin C, vitamin E, and folate intake and risk of self-reported hearing loss in women. Design: This prospective cohort study followed 65,521 women in the Nurses’ Health Study II from 1991 to 2009. Baseline and updated information obtained from validated biennial questionnaires was used in Cox proportional hazards regression models to examine independent associations between nutrient intake and self-reported hearing loss. Results: After 1,084,598 person-years of follow-up, 12,789 cases of incident hearing loss were reported. After multivariable adjustment, we observed modest but statistically significant inverse associations between higher intake of β-carotene and β-cryptoxanthin and risk of hearing loss. In comparison with women in the lowest quintile of intake, the multivariable-adjusted RR of hearing loss among women in the highest quintile was 0.88 (95% CI: 0.81, 0.94; P-trend < 0.001) for β-carotene and 0.90 (95% CI: 0.84, 0.96; P-trend < 0.001) for β-cryptoxanthin. In comparison with women with folate intake 200–399 μg/d, very low folate intake (<200 μg/d) was associated with higher risk (RR: 1.19; 95% CI: 1.01, 1.41), and higher intake tended to be associated with lower risk (P-trend = 0.04). No significant associations were observed for intakes of other carotenoids or vitamin A. Higher vitamin C intake was associated with higher risk; in comparison with women with intake <75 mg/d, the RR among women with vitamin C intake ≥1000 mg/d (mainly supplemental) was 1.22 (95% CI: 1.06, 1.42; P-trend = 0.02). There was no significant trend between intake of vitamin E intake and risk. Conclusion: Higher intakes of β-carotene, β-cryptoxanthin, and folate, whether total or from diet, are associated with lower risk of hearing loss, whereas higher vitamin C intake is associated with higher risk.

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Drouin, Guy, Jean-Remi Godin e Benoit Page. "The Genetics of Vitamin C Loss in Vertebrates". Current Genomics 12, n.º 5 (1 de agosto de 2011): 371–78. http://dx.doi.org/10.2174/138920211796429736.

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Afolabi, Ayobami Oladele, Olaolu Opeyemi Olotu e Isiaka Abdullateef Alagbonsi. "Vitamins E and C Alleviate the Germ Cell Loss and Oxidative Stress in Cryptorchidism When Administered Separately but Not When Combined in Rats". ISRN Pharmacology 2012 (30 de outubro de 2012): 1–8. http://dx.doi.org/10.5402/2012/843569.

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The antioxidant effects of vitamins C and E on cryptorchidism-induced oxidative stress were investigated in male Sprague-Dawley rats. Forty rats (200–250 g) were randomly divided in a blinded fashion into five groups (). Group 1 was sham operated and treated with vehicle (corn-oil, 10 mL/kg). Groups 2, 3, 4, and 5 were rendered unilaterally cryptorchid and treated with vehicle (10 mL/kg), vitamin E solution (75 mg/kg), vitamin C solution (1.25 g/kg), and combination of vitamin E (75 mg/kg) and vitamin C (1.25 g/kg) solutions, respectively. Germ cell count, superoxide dismutase (SOD), total protein (TP), and testicular weight (TW) were lower, but malondialdhyde (MDA) was higher in the cryptorchid rats than the sham-operated rats. When administered separately, vitamins C and E increased germ cell count, SOD, TP, and TW but did not reduce MDA in the cryptorchid rats when compared to the vehicle-treated cryptorchid rats. However, there was no significant difference in these parameters between vehicle-treated and combined vitamins C- and E-treated rats. This suggests that vitamins E and C alleviate the germ cell loss and oxidative stress in cryptorchidism when administered separately but not when combined in rats.

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Cui, Jie, Xinpu Yuan, Lina Wang, Gareth Jones e Shuyi Zhang. "Recent Loss of Vitamin C Biosynthesis Ability in Bats". PLoS ONE 6, n.º 11 (1 de novembro de 2011): e27114. http://dx.doi.org/10.1371/journal.pone.0027114.

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May, James M., Zhi-chao Qu, Huan Qiao e Mark J. Koury. "Maturational loss of the vitamin C transporter in erythrocytes". Biochemical and Biophysical Research Communications 360, n.º 1 (agosto de 2007): 295–98. http://dx.doi.org/10.1016/j.bbrc.2007.06.072.

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Halpner, Andrew D., Garry J. Handelman, Jason M. Harris, Cheryl A. Belmont e Jeffrey B. Blumberg. "Protection by Vitamin C of Loss of Vitamin E in Cultured Rat Hepatocytes". Archives of Biochemistry and Biophysics 359, n.º 2 (novembro de 1998): 305–9. http://dx.doi.org/10.1006/abbi.1998.0914.

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Cvetkovic, Biljana, e Marija Jokanovic. "Effect of preservation method and storage condition on ascorbic acid loss in beverages". Acta Periodica Technologica, n.º 40 (2009): 1–7. http://dx.doi.org/10.2298/apt0940001c.

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Global market is flooded with vitamin-enriched foods, mainly beverages. Major vitamins for enriching beverages are the antioxidant vitamins A, C and E. Ascorbic acid is readily oxidized and lost during storage of the beverages, at rates depending on the conditions of storage. This fact is of great importance for the consumer who must know how to store beverages and when to consume them in order to get the maximum benefit of added vitamin C. The objective of this paper was to determine the amount of ascorbic acid lost in beverages applying different preservation methods and storage condition. Beverage was made in laboratory conditions with synthetic L-ascorbic acid added according to the national legislations. After 30 days of storage at 4-8oC ascorbic acid overall loss was from 81.01% to 90.27% in thermally pasteurized samples and from 97.83 % to almost complete loss in samples preserved with sodium benzoate.

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Busso, Dolores, Andrea David, Reyna Penailillo, Guadalupe Echeverría, Attilio Rigotti, Irina Kovalskys, Georgina Gómez et al. "Intake of Vitamin E and C in Women of Reproductive Age: Results from the Latin American Study of Nutrition and Health (ELANS)". Nutrients 13, n.º 6 (7 de junho de 2021): 1954. http://dx.doi.org/10.3390/nu13061954.

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Vitamin E was identified as a lipophilic compound essential to maintain rat pregnancy. Low vitamin E intake during early pregnancy associates with congenital malformations and embryonic loss in animals and with miscarriage and intrauterine growth restriction in humans. Vitamin E protects cell membranes from lipoperoxidation and exerts non-antioxidant activities. Its function can be restored by vitamin C; thus, intake and circulating levels of both micronutrients are frequently analyzed together. Although substantial vitamin E inadequacy was reported worldwide, its consumption in Latin America (LatAm) is mostly unknown. Using data from the Latin American Study of Nutrition and Health (Estudio Latinoamericano de Nutrición y Salud, ELANS), we evaluated vitamin E and C intake in women of reproductive age (WRA) from eight LatAm countries and identified their main food sources. Two non-consecutive 24-h dietary recalls in 3704 women aged from 15 to 49 years and living in urban locations showed low average intake of vitamin E (7.9 mg/day vs. estimated average requirement (EAR) of 12 mg/day) and adequate overall vitamin C consumption (95.5 mg/day vs. EAR of 60 mg/day). The mean regional inadequacy was 89.6% for vitamin E and 36.3% for vitamin C. The primary food sources of vitamin E were fats and oils, as well as vegetables. Vitamin C intake was explained mainly by the consumption of fruit juices, fruits, and vegetables. Combined deficient intake of both vitamins was observed in 33.7% of LatAm women. Although the implications of low antioxidant vitamins’ consumption in WRA are still unclear, the combined deficient intake of both vitamins observed in one-third of ELANS participants underscores the need for further research on this topic.

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Deyhim, Farzad, Kimberly Strong, Niaz Deyhim, Sarvenaz Vandyousefi, Alexis Stamatikos e Bahram Faraji. "Vitamin C reverses bone loss in an osteopenic rat model of osteoporosis". International Journal for Vitamin and Nutrition Research 88, n.º 1-2 (1 de fevereiro de 2018): 58–64. http://dx.doi.org/10.1024/0300-9831/a000486.

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Abstract. Fruits and vegetables are rich in vitamin C with antioxidant properties which are known to influence bone quality. This study evaluated whether vitamin C (1000 mg/L) added to drinking water reverses the bone loss in ovariectomized rats. Ninety-day-old female Sprague-Dawley rats were randomly assigned to either sham (n = 14) or ovariecotmized groups (n = 28). Sixty days after ovariectomy, the treatments were sham, ovariectomy (OVX), OVX + vitamin C (22 mg oral intake daily) for 60 days. Urine was collected for deoxypyridinoline (DPD) evaluation, rats were sacrificed, and antioxidant capacity, osteopontin, alkaline phosphatase (ALP), and bone specific tartrate resistant acid phosphatase (TRAP) were evaluated in the plasma. Right femur and 5th lumbar were evaluated for bone density, strength, ash, Ca, and Mg concentrations. Antioxidant capacity, ALP activity, osteopontin decreased (p-value < 0.05), while TRAP and urinary DPD increased (p-value < 0.05) with ovariectomy. In contrast, vitamin C increased (p-value < 0.05) antioxidant capacity, ALP activity, osteopontin concentration and reduced (p-value < 0.05) TRAP and urinary DPD excretion, respectively. Ovariectomy reduced (p-value < 0.05) bone quality, bone ash, Ca and Mg concentrations. Vitamin C increased (p-value < 0.05) femoral density without affecting (p-value > 0.1) femoral strength, ash, or Ca, and Mg concentrations, while it increased (p-value < 0.05) the 5th lumbar density, ash, and Ca and Mg concentrations. In conclusion, vitamin C increased bone quality and antioxidant capacity in ovariectomized rats.

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Halpner, Andrew D., Garry J. Handelman, Cheryl A. Belmont, Jason M. Harris e Jeffrey B. Blumberg. "Protection by vitamin C of oxidant-induced loss of vitamin E in rat hepatocytes". Journal of Nutritional Biochemistry 9, n.º 6 (junho de 1998): 355–59. http://dx.doi.org/10.1016/s0955-2863(98)00019-9.

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Hatano, Miyako, Naoki Uramoto, Yozo Okabe, Mitsuru Furukawa e >Makoto Ito. "Vitamin E and vitamin C in the treatment of idiopathic sudden sensorineural hearing loss". Acta Oto-Laryngologica 128, n.º 2 (janeiro de 2008): 116–21. http://dx.doi.org/10.1080/00016480701387132.

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Hornung, Tabea C., e Hans-Konrad Biesalski. "Glut-1 explains the evolutionary advantage of the loss of endogenous vitamin C-synthesis". Evolution, Medicine, and Public Health 2019, n.º 1 (1 de janeiro de 2019): 221–31. http://dx.doi.org/10.1093/emph/eoz024.

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Abstract Introduction During evolution, some species including humans, monkeys and fruit bats lost the ability for ascorbic acid (AA) biosynthesis due to inactivation of the enzyme l-gulono-lactone oxidase (GLO) and subsequently became dependent on dietary vitamin C. There are four current hypotheses in relation to the benefit of vitamin C dependence in the context of adaptation and reproduction. Here we advance and test a new ‘electron transfer hypothesis’, which focusses on the role of the expression of glucose transporter 1 (Glut-1) in red blood cells (RBCs) in recycling vitamin C, thereby increasing the efficiency of micronutrient uptake. Methods To evaluate the benefit of Glut-1 expression, we determined vitamin C uptake into RBCs and potential release from two different species, humans with l-Gulono-lactone-oxidase (GLO-loss) and pigs with functional GLO. Results The oxidized form of vitamin C (dehydroascorbate, DHA) was transported into human RBCs via Glut-1. There was no transport of either the reduced (AA) or the oxidized vitamin in pig erythrocytes. Conclusion We propose that the transport of vitamin C increases an intracellular electron pool, which transfers electrons from intracellular ascorbate to extracellular substances like ascorbyl free radical or DHA, resulting in 100-fold smaller daily requirement of this essential redox sensitive micronutrient. This would be an advantage during seasonal changes of the availability from food and may be the key for the survival of individuals without vitamin C biosynthesis. Lay Summary 40 million years ago some individuals lost the ability to synthesize vitamin C. Why did they survive such as humans until now? Individuals with a specific glucose transporter Glut-1 on their erythrocytes which transports vitamin C need less and are protected from scarcity due to seasons and food competitors.

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Takahashi, Fuyuko, Yoshitaka Hashimoto, Ayumi Kaji, Ryosuke Sakai, Yuka Kawate, Takuro Okamura, Yuriko Kondo et al. "Vitamin Intake and Loss of Muscle Mass in Older People with Type 2 Diabetes: A Prospective Study of the KAMOGAWA-DM Cohort". Nutrients 13, n.º 7 (8 de julho de 2021): 2335. http://dx.doi.org/10.3390/nu13072335.

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The aim of this prospective cohort study was to examine the relationships between the intakes of various vitamins and the loss of muscle mass in older people with type 2 diabetes (T2DM). The change in skeletal muscle mass index (SMI, kg/m2) (kg/m2/year) was defined as follows: (SMI at baseline (kg/m2) − SMI at follow-up (kg/m2))/follow-up period (year). The rate of SMI reduction (%) was calculated as follows (the change in SMI (kg/m2/year)/SMI at baseline (kg/m2)) × 100. The rate of SMI reduction ≥ 1.2% was considered as the loss of muscle mass. Among 197 people with T2DM, 47.2% of them experienced the loss of muscle mass at the 13.7 ± 5.2 month follow-up. Vitamin B1 (0.8 ± 0.3 vs. 0.8 ± 0.3 mg/day, p = 0.031), vitamin B12 (11.2 ± 8.3 vs. 13.4 ± 7.5 μg/day, p = 0.049), and vitamin D (16.5 ± 12.2 vs. 21.6 ± 13.0 μg/day, p = 0.004) intakes in people with the loss of muscle mass were significantly lower than those without. Vitamin D intake was related to the loss of muscle mass after adjusting for sex, age, exercise, alcohol, smoking, body mass index, SMI, glucagon-like peptide-1 agonist, sodium glucose cotransporter-2 inhibitor, insulin, HbA1c, creatinine, energy intake, and protein intake (adjusted odds ratio 0.93, 95% confidence interval: 0.88–0.97, p = 0.003). This study showed that vitamin D intake was related to the loss of muscle mass in older people with T2DM. Vitamin B12 intake tended to be related to the loss of muscle mass, although vitamin A, vitamin B2, vitamin B6, vitamin C, and vitamin E intake were not related.

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Cui, Jie, Yi-Hsuan Pan, Yijian Zhang, Gareth Jones e Shuyi Zhang. "Progressive Pseudogenization: Vitamin C Synthesis and Its Loss in Bats". Molecular Biology and Evolution 28, n.º 2 (29 de outubro de 2010): 1025–31. http://dx.doi.org/10.1093/molbev/msq286.

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Carlson, Beth L., e Mary H. Tabacchi. "Loss of vitamin C in vegetables during the foodservice cycle". Journal of the American Dietetic Association 88, n.º 1 (janeiro de 1988): 65–67. http://dx.doi.org/10.1016/s0002-8223(21)01917-9.

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Kholis, Nur, Ujang Suryadi e Faturrahman Roni. "Pengaruh Suplementasi Vitamin C dan Jarak Transportasi Terhadap Penyusutan Bobot Badan Broiler". Jurnal Ilmu Peternakan Terapan 2, n.º 1 (28 de dezembro de 2018): 27–33. http://dx.doi.org/10.25047/jipt.v2i1.1166.

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The purpose of this study was to know the effect of vitamin C supplementation and distance transportation on broiler weight loss. The method used in this study using 128 days of unisexing broiler. The experimental design used a Factorial Completely Randomized Design. The experimental factor consisted of 2 factors, such as the distance factor with 2 levels, 24 km (a1) and 48 km (a2), and the sumplemetation factor of vitamin C with 4 levels such as 0 mg/L (b1), 250 mg/L (b2), 500 mg/L (b3), and 750 mg/L (b4). The experiment was 4 times replication. If obtained significantly result, continued by Least Significant Difference test (LSD). Vitamin C supplementation was significant to weight loss, heart rate, glucose, and mortality in broilers during transportation. The transportation mileage was significant to weight loss and heart rate in broilers. Supplementation of vitamin C and transportation mileage provided a significant interaction weight loss, heart rate, glucose, and mortality in broilers.

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Samsel, Konrad, e Abizar Meghani. "The Effects of Commercial Freezing on Vitamin Concentrations in Spinach (Spinacia oleracea)". Journal of Undergraduate Life Sciences 15, n.º 1 (23 de julho de 2021): 9. http://dx.doi.org/10.33137/juls.v15i1.37032.

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Commercial food processing has had a significant impact on reducing food spoilage and increasing accessibility to nutrient-dense vegetables. The commercial freezing process, in particular, has given producers the ability to store vegetables with minimized risk of microbial and enzymatic spoilage. Despite the effectiveness of freezing as a preservation method, there is evidence that pre-freezing procedures and prolonged storage can reduce the concentration of vitamins present within certain vegetables. Spinach, one of the most widely produced and consumed vegetables, is particularly susceptible to nutrient loss during the commercial freezing process due to its large surface area and high mineral content. This review summarizes the known effects of the freezing process on hydrophilic and lipophilic vitamins including vitamin C, thiamin, riboflavin, β-carotene, and α-tocopherol. There are two key mechanisms that lead to decreased vitamin concentrations, with the first being attributed to pre-freezing processes including washing and blanching which favours the leaching of hydrophilic vitamins. The second mechanism of vitamin loss is attributed to residual enzymatic activity during storage, where the degree of residual activity can be partially attributed to differences in blanching protocols and freezing practices. Understanding the mechanisms and extent of vitamin loss that the commercial freezing process imparts on leafy green vegetables can help inform future research on improved food processing methods that minimize nutrient loss. Implementing procedures that maintain nutrient retention in frozen vegetables has the potential to assist individuals in achieving their recommended daily intakes of micronutrients.

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Lahučký, R., IBahelka, K. Novotná e K. Vašíčková. "Effects of dietary vitamin E and vitamin C supplementation on the level of α-tocopherol and L-ascorbic acid in muscle and on the antioxidative status and meat quality of pigs". Czech Journal of Animal Science 50, No. 4 (6 de dezembro de 2011): 175–84. http://dx.doi.org/10.17221/4012-cjas.

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In total thirty pigs (Slovak Meaty) defined by DNA based test as not susceptible to malignant hyperthermia (non-mutant on RYR1) were used in the experiment. Treatment consisted in supplementation of vitamin E (500 mg α-tocopherol/kg diet as α-tocopherol acetate) (group E) and the same doses of vitamin E plus vitamin C (200 mg L-ascorbic acid/kg diet) (group E + C) to finishing pigs for the last 30 days before slaughter. The higher dietary vitamin E level resulted in higher levels of α-tocopherol in fresh (24 h), chill-stored (5 days, 4°C), chill-stored and cooked (80°C) and frozen meat (3 months, –25°C), (P < 0.05). Higher dietary vitamin C resulted in higher levels L-ascorbic acid in fresh and chill-stored meat (P < 0.05) but no significant differences vs. control pigs were observed in cooked and frozen meats. Supplementation with vitamins E and C (group E + C) had positive effects on pH (45 min) (P = 0.06) and on drip loss (P < 0.05) values as compared to control group. The rate of oxidation (malondialdehyde-MDA production) by stimulation with Fe<sup>2+</sup>/ascorbate (incubation of muscle LD for 0 and 30 min) was higher in control group as compared to both experimental groups (P < 0.05). Positive effects of vitamin E on oxidative stability measured as thiobarbituric acid reactive substances (TBARS, MDA) were observed mainly in chill-stored meat (P < 0.05). Using TBARS method, no additional effect of vitamin C on oxidative stability of fresh, chill-stored, cooked and frozen meat was found. In conclusion, supplementation of the combination of vitamin E (500 mg α-tocopherol/kg diet) and vitamin C (200 mg L-ascorbic acid/kg diet) for 30 days before slaughter improved meat quality values (drip loss, pH), however, it seems to depend on the genetic background of animals (occurrence of mutation on RYR1). Oxidative stability of meat lipids measured as TBARS value can be improved by vitamin E supplementation to feed.  

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FELLMAN, ROSE L., PAUL S. DIMICK e RUTH HOLLENDER. "Photooxidative Stability of Vitamin A Fortified 2% Lowfat Milk and Skim Milk". Journal of Food Protection 54, n.º 2 (1 de fevereiro de 1991): 113–16. http://dx.doi.org/10.4315/0362-028x-54.2.113.

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Lowfat milk and skim milk were fortified with either oil- or aqueous-based carrier blends of vitamins A and D, in 1-gal poly-ethylene containers, and illuminated up to 72 h with 1080 1× (100 ft-c) at 5°C in a commercial display case. Vitamin A measurments and sensory analyses showed that vitamin A was more stable in 2% lowfat milk than in skim milk regardless of the carrier. The aqueous-based carrier provided more stability in lowfat milk while the oil-based carrier gave more stability in skim milk. Skim milk fortified with the aqueous-based vitamin A had 69% loss, while the unexposed control exhibited only 15% loss of the vitamin. Off-flavors were evident after 6 h in light-exposed 2% lowfat milk with the oil-based vitamin A, but the same milk with aqueous-based vitamin A did not exhibit off-flavors until after 12 h. Both 2% lowfat and skim milk samples exposed to light received similar lowered preference scores compared to nonexposed control samples. When both fortified and nonfortified 2% lowfat and skim milk samples were tasted after exposure to light, the flavor was not significantly different, but were in the unacceptable range.

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Lavoie, Jean-Claude, Philippe Chessex, Thérèse Rouleau, Diane Migneault e Blandine Comte. "Light-Induced Byproducts of Vitamin C in Multivitamin Solutions". Clinical Chemistry 50, n.º 1 (1 de janeiro de 2004): 135–40. http://dx.doi.org/10.1373/clinchem.2003.025338.

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Abstract Background: When solutions of multivitamin preparations (MVPs) are exposed to light, H2O2 as well as organic peroxides are generated and the concentration of vitamin C decreases. The aim of this study was to determine, using mass spectrometry, whether the generation of oxidative byproducts of vitamin C, such as dehydroascorbate (DHA) and 2,3-diketogulonic acid (DKG), accounted for the reported decrease in ascorbic acid in MVPs exposed to light. Methods: Mass spectrometry was used to document the formation of byproducts of ascorbic acid in solutions containing a MVP, vitamin C + riboflavin, and vitamin C + H2O2 + Fe2+. The involvement of ascorbic acid and H2O2 in the formation of organic peroxides was tested by measuring peroxide concentrations in solutions containing H2O2 with or without ascorbic acid and with or without Fe2+ before and after addition of catalase. Results: The loss of ascorbic acid in photo-exposed MVPs was associated with the concomitant generation of byproducts different from DHA and DKG. Among them, one mass fingerprint was particularly observed with solutions of vitamin C + riboflavin exposed to ambient light as well as with the solution of vitamin C + H2O2 + Fe2+, suggesting a Fenton-like reaction. This fingerprint was associated with the formation of catalase-resistant peroxides. Conclusion: Exposure of MVPs to light leads to the rapid loss of ascorbic acid and generation of specific byproducts that differ from DHA and DKG. The conversion of vitamin C into byproducts could be of biological importance in accounting for the decrease in ascorbic acid concentrations and the generation of organic peroxides in light-exposed MVPs.

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Nejatinamini, Sara, Brock Debenham, Robin Clugston, Asifa Mawani, Matthew Parliament, Wendy Wismer e Vera Mazurak. "Poor Vitamin Status is Associated with Skeletal Muscle Loss and Mucositis in Head and Neck Cancer Patients". Nutrients 10, n.º 9 (5 de setembro de 2018): 1236. http://dx.doi.org/10.3390/nu10091236.

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Mucositis and muscle wasting are two common toxicity effects of cancer treatment in head and neck cancer (HNC). There is limited data evaluating cancer treatment toxicities in relation to vitamin status. This study aimed to assess changes in vitamin status during HNC treatment in relation to body composition, inflammation and mucositis. In this prospective cohort study, dietary intakes (3-day food record), plasma levels of vitamins and C-reactive protein (CRP) were assessed at baseline (at diagnosis) and post-treatment (after 6–8 weeks of radiation therapy with or without chemotherapy). Computed tomography images were used to quantify body composition. Mucositis information was collected from health records of patients. Twenty-eight HNC patients (age 60 ± 10 years) completed both study time points. Patients who developed mucositis had significantly lower dietary intake of vitamins and plasma 25-hydroxy vitamin D (25-OHD) and all-trans retinol levels (p < 0.02). Patients lost a considerable amount of muscle mass (3.4 kg) and fat mass (3.6 kg) over the course of treatment. There was a trend toward greater muscle loss in patients with 25-OHD < 50 nmol/L compared to patients with 25-OHD ≥ 50 nmol/L (p = 0.07). A significant negative correlation was found between plasma all-trans retinol and CRP level at the end of treatment (p = 0.03). Poor vitamin status could be a contributing factor in developing treatment-induced toxicities.

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Yavuz, Turhan, Irfan Altuntas, Namik Delibas, Bekir Yildirim, Ozden Candir, Ahmet Corâ, Nermin Karahan, Erdogan Ibrisim e Ali Kutsal. "Cardiotoxicity in rats induced by methidathion and ameliorating effect of vitamins E and C". Human & Experimental Toxicology 23, n.º 7 (julho de 2004): 323–29. http://dx.doi.org/10.1191/0960327104ht456oa.

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We have examined the effect of subchronic methidathion (MD) administration on heart damage, and have evaluated possible ameliorating effects of a combination of vitamins E and C against MD toxicity. The experimental groups were: control group, rats treated with 5 mg/kg MD and rats treated with 5 mg/kg body weight MD plus vitamin E and vitamin C (MD+Vit). The groups were given MD by gavage 5 days a week for four weeks at a dose level of 5 mg/kg/day (MD and MD+Vit) by using corn oil as the vehicle. Vitamin E and vitamin C were injected at doses of 50 mg/kg i.m. and 20 mg/kg i.p., respectively, after the treatment with MD in the MD+Vit group. The levels of malondialdehyde (MDA) were determined in the heart tissue, and the levels of cardiac troponin I (TnI) in serum. An autoanalyser was used to determine the serum activities of cholinesterase (ChE). Histopathological examination was carried out in the heart tissue. MDA significantly increased in the MD group as compared to controls (P <0.01). When MD was given concurrently with vitamins E and C, the increase in MDA was significantly less (P <0.01). ChE activity significantly decreased in the MD group as compared to controls (P <-0.01). When MD was given concurrently with vitamins E and C, the decrease in ChE activity was significantly higher (P <-0.05). The serum TnI levels significantly increased in the MD group as compared to controls (P <-0.01). When MD was given concurrently with vitamins E and C, the increase in the serum TnI was significantly less (P <-0.01). MD caused the diffuse loss of striation and myocytolysis of the cardiomyocytes, whereas the combination of vitamins E and C caused a significant decrease in these effects of MD. In conclusion, subchronic MD administration caused heart damage and, in addition, treatment with a combination of vitamins E and C after the administration of MD reduced heart damage caused by MD.

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Ramezanipour, Masoud, Mahmood Jalali, Haleh Sadrzade-Yeganeh, Seyed Ali Keshavarz, Mohammad Reza Eshraghian, Minoo Bagheri e Sara Seyed Emami. "The effect of weight reduction on antioxidant enzymes and their association with dietary intake of vitamins A, C and E". Arquivos Brasileiros de Endocrinologia & Metabologia 58, n.º 7 (outubro de 2014): 744–49. http://dx.doi.org/10.1590/0004-2730000003206.

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Objective Our goal was to assess the effects of weight loss on antioxidant enzymes of red blood cells and it’s relation with vitamins A, E and C intake in 30 obese women. Subjects and methods General information, anthropometric measurements, 3-day food recall, and fasting blood samples were collected from 30 obese women at the beginning of the study and after 3 months intervention. Weight loss was set at about 10% of their weight before the intervention. Results Glutathione reductase and catalase activities showed a significant increase (P < 0.01) after weight reduction, but no significant changes were seen in the superoxide dismutase and glutathione peroxidase activities. There was a positive linear correlation between daily vitamin C intake with superoxide dismutase enzyme after intervention (P = 0.004, r = 0.507). There was a negative linear correlation between vitamin E intake and glutathione peroxidase activity before intervention (P = 0.005, r = -0.5). A negative correlation was found between daily vitamin A intake and glutathione reductase enzyme before and after intervention (r = -0.385, r = -0.397, P < 0.05) respectively. No significant correlation was observed between vitamins A, C, E amounts and catalase activity. Conclusions Ten percent weight reduction can have a significant role in increasing antioxidant enzymes activities, especially glutathione reductase, and catalase enzymes in obese women. However, it is important to take into consideration a balanced amount of certain nutrients while administering a diet with limited energy.

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Belbase, Rupesh Jung, Amrut Diwakar Raje e Anchal Singh. "A review on the role of macro and micro nutrients in bone health". International Journal of Research in Orthopaedics 5, n.º 5 (26 de agosto de 2019): 995. http://dx.doi.org/10.18203/issn.2455-4510.intjresorthop20193851.

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<p class="abstract">Osteoporosis is a major public health problem, affecting many individuals. The aging population will require problem related prevention, education, and treatment to maintain bone density and reduce the bone fractures and falls. Inadequate intake of nutrients increases the risk for bone loss and subsequent osteoporosis. Protein, calcium and vitamin D are vital nutrients for optimal bone health. Adequate calcium is essential for bone maintenance. There are several other vitamin and mineral needed for metabolic processes related to good bone health, including manganese, copper, iron, zinc, vitamin A, vitamin K, vitamin C and the B vitamins. Related macro- and micronutrients play an important role in bone mass integrity and quality. Adequate nutrition for older adults needs to be encouraged to promote and maintain bone health.</p>

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Paciolla, Costantino, Stefania Fortunato, Nunzio Dipierro, Annalisa Paradiso, Silvana De Leonardis, Linda Mastropasqua e Maria Concetta de Pinto. "Vitamin C in Plants: From Functions to Biofortification". Antioxidants 8, n.º 11 (29 de outubro de 2019): 519. http://dx.doi.org/10.3390/antiox8110519.

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Vitamin C (l-ascorbic acid) is an excellent free radical scavenger, not only for its capability to donate reducing equivalents but also for the relative stability of the derived monodehydroascorbate radical. However, vitamin C is not only an antioxidant, since it is also a cofactor for numerous enzymes involved in plant and human metabolism. In humans, vitamin C takes part in various physiological processes, such as iron absorption, collagen synthesis, immune stimulation, and epigenetic regulation. Due to the functional loss of the gene coding for l-gulonolactone oxidase, humans cannot synthesize vitamin C; thus, they principally utilize plant-based foods for their needs. For this reason, increasing the vitamin C content of crops could have helpful effects on human health. To achieve this objective, exhaustive knowledge of the metabolism and functions of vitamin C in plants is needed. In this review, the multiple roles of vitamin C in plant physiology as well as the regulation of its content, through biosynthetic or recycling pathways, are analyzed. Finally, attention is paid to the strategies that have been used to increase the content of vitamin C in crops, emphasizing not only the improvement of nutritional value of the crops but also the acquisition of plant stress resistance.

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Ibrahim, Iman, Anthony Zeitouni e Sabrina Daniela da Silva. "Effect of Antioxidant Vitamins as Adjuvant Therapy for Sudden Sensorineural Hearing Loss: Systematic Review Study". Audiology and Neurotology 23, n.º 1 (2018): 1–7. http://dx.doi.org/10.1159/000486274.

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Importance: Sudden sensorineural hearing loss (SSNHL) is an otological emergency of unknown etiology. Recent reports showed that antioxidant drugs can benefit patients with SSNHL. This study attempted to evaluate the effect of adding antioxidant vitamins as an adjuvant therapy alongside with corticosteroids. Objective: To evaluate the effects of the 3 major antioxidant vitamins (A, C, and E) as an adjuvant therapy, administered with corticosteroids, for the treatment of SSNHL in adult patients (≥18 years). Data Sources: MEDLINE, EMBASE, PubMed, Web of Science and Cochrane electronic databases from January 1, 1995, through September 25, 2017. Study Selection: Published studies of adult patients who received antioxidant vitamins (A, C, E, or any combination of these vitamins) as an adjuvant therapy in addition to the regular treatment (corticosteroids) for SSNHL. Quality assessment was performed using the Cochrane Collaboration Tool for Assessing Risk of Bias. Data Extraction: Each study had a control group (conventional treatment + placebo) and a trial group (antioxidant vitamin(s) + conventional treatment). Results: From 446 manuscripts identified in the literature, 3 studies were included in the review with 279 patients. The most common vitamins used to treat SSNHL were the 3 major antioxidant vitamins A, C, and E, combined sometimes with other antioxidants such as selenium. Conclusions and Relevance: The success of the treatment is increased in patients who received antioxidant vitamins in combination with conventional therapy.

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Johnston, Carol S. "Strategies for Healthy Weight Loss: From Vitamin C to the Glycemic Response". Journal of the American College of Nutrition 24, n.º 3 (junho de 2005): 158–65. http://dx.doi.org/10.1080/07315724.2005.10719460.

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Wills, R. B. H., e Jansen Silalahi. "Effect of storage temperature on loss of vitamin C in potato crisps". Journal of the Science of Food and Agriculture 53, n.º 2 (1990): 275–78. http://dx.doi.org/10.1002/jsfa.2740530216.

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Hu, Jinwei, O’neil Guthrie, Subburaman Mohan e Timothy T. K. Jung. "Vitamin C Deficiency–Induced Hearing Loss and Ossicular Defect in Transgenic Mice". Otolaryngology–Head and Neck Surgery 149, n.º 2_suppl (23 de agosto de 2013): P239. http://dx.doi.org/10.1177/0194599813496044a296.

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McFadden, Sandra L., Jenifer M. Woo, Nathan Michalak e Dalian Ding. "Dietary vitamin C supplementation reduces noise-induced hearing loss in guinea pigs". Hearing Research 202, n.º 1-2 (abril de 2005): 200–208. http://dx.doi.org/10.1016/j.heares.2004.10.011.

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Maidhah, Andi, e Shinta Tri Kismanti. "VITAMIN C SEBAGAI INHIBITOR KOROSI BAJA API 5L GRADE B DENGAN VARIASI ALIRAN DI LINGKUNGAN ASAM LEMAH PH 5". INOVTEK POLBENG 9, n.º 1 (3 de julho de 2019): 103. http://dx.doi.org/10.35314/ip.v9i1.963.

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Senyawa organik yang aman pemakaiannya pada lingkungan dan tersedia secara komersial menjadi alasan pemakaian vitamin C sebagai inhibitor korosi untuk baja API 5L grade B. Penghambatan korosi pada baja API 5L grade B di lingkungan asam pH 5 oleh vitamin C dilakukan dengan metode weight loss, polarisasi linear, foto makro, dan FTIR. Nilai laju korosi baja API 5L grade B dan efisiensi inhibitor didapatkan dari uji weight loss selama 30 hari perendaman dengan variasi konsentrasi inhibitor vitamin C mulai dari 0- 250 ppm dilingkungan asam pH 5. Lingkungan logam diberi variasi putaran dari 200 dan 400 rpm. Penambahan inhibitor 250 ppm dengan laju putaran 400 rpm mampu menurunkan laju korosi baja API 5L grade B dengan efisiensi inhibitor mencapai 71.68% dihari ke-30 perendaman. Uji foto makro dan FTIR membuktikan adanya pembentukan lapisan pelindung pada permukaan baja API 5L grade B yang telah diberi penambahan inhibitor vitamin C. `

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Ebrahem, Kais S., Daryl G. Richardson e Richard M. Tetley. "274 EFFECTS OF STORAGE TEMPERATURE, KERNEL INTACTNESS, AND ROASTING TEMPERATURE ON VITAMIN E, FATTY ACIDS AND PEROXIDE VALUE OF HAZELNUTS". HortScience 29, n.º 5 (maio de 1994): 469c—469. http://dx.doi.org/10.21273/hortsci.29.5.469c.

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Kernels in the shell were compared to bare kernels with pellicles, half nuts, blanched nuts, finely chopped nuts, and roasted nuts. Whole nuts and whole kernels were stable for up to two years of storage provided they had not been exposed to high temperatures. Nuts stored at low temperatures (0 and 5°C) did not lose significant amounts of vitamin E. Increasing surface area by dividing nuts or finely chopping them, increased the loss of vitamin E. Samples that had lower surface areas did not lose much vitamin E and peroxide value was low. Higher roasting temperatures caused losses in vitamin E and increased peroxide values at the beginning and during storage, even when stored at 0°C. Intact nuts and low storage temperatures did not show changes in fatty acid composition. High temperature treatments changed fatty acid composition, mainly decreasing linoleic initially and finally oleic acids.

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Welch, Ailsa A. "Nutritional influences on age-related skeletal muscle loss". Proceedings of the Nutrition Society 73, n.º 1 (12 de novembro de 2013): 16–33. http://dx.doi.org/10.1017/s0029665113003698.

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Age-related muscle loss impacts on whole-body metabolism and leads to frailty and sarcopenia, which are risk factors for fractures and mortality. Although nutrients are integral to muscle metabolism the relationship between nutrition and muscle loss has only been extensively investigated for protein and amino acids. The objective of the present paper is to describe other aspects of nutrition and their association with skeletal muscle mass. Mechanisms for muscle loss relate to imbalance in protein turnover with a number of anabolic pathways of which the mechanistic TOR pathway and the IGF-1–Akt–FoxO pathways are the most characterised. In terms of catabolism the ubiquitin proteasome system, apoptosis, autophagy, inflammation, oxidation and insulin resistance are among the major mechanisms proposed. The limited research associating vitamin D, alcohol, dietary acid–base load, dietary fat and anti-oxidant nutrients with age-related muscle loss is described. Vitamin D may be protective for muscle loss; a more alkalinogenic diet and diets higher in the anti-oxidant nutrients vitamin C and vitamin E may also prevent muscle loss. Although present recommendations for prevention of sarcopenia focus on protein, and to some extent on vitamin D, other aspects of the diet including fruits and vegetables should be considered. Clearly, more research into other aspects of nutrition and their role in prevention of muscle loss is required.

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Agarwal, Ankita, David N. Hager e Jonathan E. Sevransky. "Any Role of High-Dose Vitamin C for Septic Shock in 2021?" Seminars in Respiratory and Critical Care Medicine 42, n.º 05 (20 de setembro de 2021): 672–82. http://dx.doi.org/10.1055/s-0041-1733986.

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AbstractWhile the use of vitamin C as a therapeutic agent has been investigated since the 1950s, there has been substantial recent interest in the role of vitamin C supplementation in critical illness and particularly, sepsis and septic shock. Humans cannot synthesize vitamin C and rely on exogenous intake to maintain a plasma concentration of approximately 70 to 80 μmol/L. Vitamin C, in healthy humans, is involved with antioxidant function, wound healing, endothelial function, and catecholamine synthesis. Its function in the human body informs the theoretical basis for why vitamin C supplementation may be beneficial in sepsis/septic shock.Critically ill patients can be vitamin C deficient due to low dietary intake, increased metabolic demands, inefficient recycling of vitamin C metabolites, and loss due to renal replacement therapy. Intravenous supplementation is required to achieve supraphysiologic serum levels of vitamin C. While some clinical studies of intravenous vitamin C supplementation in sepsis have shown improvements in secondary outcome measures, none of the randomized clinical trials have shown differences between vitamin C supplementation and standard of care and/or placebo in the primary outcome measures of the trials. There are some ongoing studies of high-dose vitamin C administration in patients with sepsis and coronavirus disease 2019; the majority of evidence so far does not support the routine supplementation of vitamin C in patients with sepsis or septic shock.

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Berrocal, M. C., e A. Abeger. "Note. Shelf life of a saturated vitamin E carrier system for use in the food industry / Nota. Vida útil de un sistema de microencapsulación de vitamina E para alimentos". Food Science and Technology International 5, n.º 6 (dezembro de 1999): 509–13. http://dx.doi.org/10.1177/108201329900500609.

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Dimyristoylphosphatidylcholine liposomes containing different concentrations of vitamin E (0, 5, 15 and 25%) were prepared by extrusion through 100 nm pore size filters, and stored at 5 °C in the dark under an oxygen atmosphere. The physico-chemical characteristics chosen as shelf life indicators for this vitamin E-carrier system were vitamin E fluorescence, mean diameter of the system, products of phospholipid oxidation and total products of lipid degradation. Encapsulated vitamins underwent an exponential degradation process (first order kinetics). The complete alteration of the system was confirmed by thin layer chromatography on the 150th day of storage (16% remaining vitamin) al though this did not affect the macroscopic appearance of the suspension. Physical stability was con firmed by the mean diameter which ranged from 85.1 ±5.2 nm to 69.7±5.1 nm without the loss of the monodisperse nature of the liposome suspension.

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Byarushengo, Denice, Rwaichi Minja e Abraham Temu. "Lemongrass and Cinnamon Essential Oils as Vitamin C Preservatives and Flavour Enhancers in Jam". Tanzania Journal of Engineering and Technology 35, n.º 1 (30 de junho de 2014): 46–53. http://dx.doi.org/10.52339/tjet.v35i1.468.

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Lemongrass and cinnamon essential oils (LEO and CEO) are natural oils with high anti-oxidation capacity, pleasant flavour, and various health benefits. Their ability to preservevitamin C and flavour in jam have not been tested. In this study the performance of twoessential oils (EOs) in preserving vitamin C and improving jam flavour were investigated.The EOs were produced by hydro-steam distillation of fresh lemongrasses and cinnamonleaves using a Clevenger apparatus. Jam samples were dosed with various concentrationsof either single or mixed EOs and then stored at either room or refrigeration temperature.Samples were analysed for changes in vitamin C content and flavour, after every 10 daysfor 60 days. Vitamin C content was determined using 2,6 dichlorophenol indophenol visualtitration method, whereas sensory analysis was done by five semi trained panellists. It wasrevealed that both LEO and CEO have high potential to reduce loss of vitamin C andimpart better flavour in pineapple jam. The improved quality of the jam is due to anti-microbial and anti-oxidant effects of the essential oils as reported in literature. Mixing theEOs had synergistic effect which maximizes their potential to reduce vitamin C loss withlower dose than when used individually. Mixed EOs doses also enhanced the jam flavour.

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Reis, Luzia Caroline Ramos dos, Ester Alice Ferreira, Heloisa Helena Siqueira Elias, Eduardo Valerio Vilas Boas e Alessandro De Oliveira Rios. "Postharvest conservation of fresh and minimally processed ‘Dekopon’ tangerine in different temperatures and storage times". Brazilian Journal of Food Research 9, n.º 1 (1 de janeiro de 2018): 112. http://dx.doi.org/10.3895/rebrapa.v9n1.5348.

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This study aimed to evaluate the effect of refrigeration and the storage time of fresh and minimally processed tangerine 'Dekopon' seeking to increase its useful life for marketing. In experiment 1, the harvested fruit were stored in temperatures of 4, 8 and 12 °C and analyzed in 0, 5 and 10 days. In experiment 2, the fruit were minimally processed and storage at temperatures of 4, 8 and 12 °C and analyzed 0, 3, 6, 9 and 12 days. The analysis of the evaluated data were weight loss, pH, total soluble solids (TSS), titratable acidity (TA), ratio TSS:TA, Vitamin C and color parameters. The results for experiment 1 showed that in general, day 0 presented higher values of physicochemical parameters and day 5 at 8 °C presented higher concentration of vitamin C. For experiment 2, in the minimally processed fruit, day 3 demonstrated more retention of physicochemical parameters, except for mass loss and day 12 at 4 °C resulted in a higher content of vitamin C.

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Liu, An Jun, Jing Guo, Ying Chen, Zi Jian Wang e An Guo Teng. "Protective Effects of Processing Condition and Antioxidant on Vitamin A in Chicken Liver Sausage". Advanced Materials Research 864-867 (dezembro de 2013): 541–44. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.541.

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In this study, the protective effects of processing conditions and antioxidants on vitamin A in chicken liver sausage were investigated. The optimal cooking conditions were determined: 80°C 30min. Under this condition, vitamin A loss rate was lowest. Different types of antioxidants vitamin C (ascorbic acid)EDTA-2Na (ethylenediaminetetraacetic acid disodium salt)BHT (2,4-di-tert.-butyl hydroxytoluene) were added to protect vitamin A. The results indicated the added antioxidants have obvious protective effects on vitamin A, and the protection effect of BHT is better than the others.

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Yue, Xiaojing, e Anjana Rao. "TET family dioxygenases and the TET activator vitamin C in immune responses and cancer". Blood 136, n.º 12 (17 de setembro de 2020): 1394–401. http://dx.doi.org/10.1182/blood.2019004158.

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Abstract Vitamin C serves as a cofactor for Fe(II) and 2-oxoglutarate–dependent dioxygenases including TET family enzymes, which catalyze the oxidation of 5-methylcytosine into 5-hydroxymethylcytosine and further oxidize methylcytosines. Loss-of-function mutations in epigenetic regulators such as TET genes are prevalent in hematopoietic malignancies. Vitamin C deficiency is frequently observed in cancer patients. In this review, we discuss the role of vitamin C and TET proteins in cancer, with a focus on hematopoietic malignancies, T regulatory cells, and other immune system cells.

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Lewis, Lucy N., Richard P. G. Hayhoe, Angela A. Mulligan, Robert N. Luben, Kay-Tee Khaw e Ailsa A. Welch. "Lower Dietary and Circulating Vitamin C in Middle- and Older-Aged Men and Women Are Associated with Lower Estimated Skeletal Muscle Mass". Journal of Nutrition 150, n.º 10 (27 de agosto de 2020): 2789–98. http://dx.doi.org/10.1093/jn/nxaa221.

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ABSTRACT Background Age-related loss of skeletal muscle mass contributes to poor outcomes including sarcopenia, physical disability, frailty, type 2 diabetes, and mortality. Vitamin C has physiological relevance to skeletal muscle and may protect it during aging, but few studies have investigated its importance in older populations. Objectives We aimed to investigate cross-sectional associations of dietary and plasma vitamin C with proxy measures of skeletal muscle mass in a large cohort of middle- and older-aged individuals. Methods We analyzed data from >13,000 men and women in the European Prospective Investigation into Cancer and Nutrition–Norfolk cohort, aged 42–82 y. Fat-free mass (FFM), as a proxy for skeletal muscle mass, was estimated using bioelectrical impedance analysis and expressed as a percentage of total mass (FFM%) or standardized by BMI (FFMBMI). Dietary vitamin C intakes were calculated from 7-d food diary data, and plasma vitamin C was measured in peripheral blood. Multivariable regression models, including relevant lifestyle, dietary, and biological covariates, were used to determine associations between FFM measures and quintiles of dietary vitamin C or insufficient compared with sufficient plasma vitamin C (<50 μmol/L and ≥50 μmol/L). Results Positive trends were found across quintiles of dietary vitamin C and FFM measures for both sexes, with interquintile differences in FFM% and FFMBMI of 1.0% and 2.3% for men and 1.9% and 2.9% for women, respectively (all P < 0.001). Similarly, FFM% and FFMBMI measures were higher in participants with sufficient than with insufficient plasma vitamin C: by 1.6% and 2.0% in men, and 3.4% and 3.9% in women, respectively (all P < 0.001). Associations were also evident in analyses stratified into <65-y and ≥65-y age groups. Conclusions Our findings of positive associations, of both dietary and circulating vitamin C with measures of skeletal muscle mass in middle- and older-aged men and women, suggest that dietary vitamin C intake may be useful for reducing age-related muscle loss.

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Varadharaj, Saradhadevi, Tonya Watkins, Arturo J. Cardounel, Joe G. N. Garcia, Jay L. Zweier, Periannan Kuppusamy, Viswanathan Natarajan e Narasimham L. Parinandi. "Vitamin C-Induced Loss of Redox-Dependent Viability in Lung Microvascular Endothelial Cells". Antioxidants & Redox Signaling 7, n.º 1-2 (janeiro de 2005): 287–300. http://dx.doi.org/10.1089/ars.2005.7.287.

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Kunes, Jacob P., Katie S. Cordero-Koning, Lionel H. Lee e Sean M. Lynch. "Vitamin C attenuates hypochlorite-mediated loss of paraoxonase-1 activity from human plasma". Nutrition Research 29, n.º 2 (fevereiro de 2009): 114–22. http://dx.doi.org/10.1016/j.nutres.2009.01.003.

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Marhiere Akpomie, Timothy, Musa Safiyanu Tanko e Umar Faruk Hassan. "Modeling the Rate of Vitamin C Loss in Five Different Fruits During Storage". Mathematical Modelling and Applications 5, n.º 4 (2020): 214. http://dx.doi.org/10.11648/j.mma.20200504.12.

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Munday, Molly-Rose, Rohan Rodricks, Michael Fitzpatrick, Victoria M. Flood e Jenny E. Gunton. "A Pilot Study Examining Vitamin C Levels in Periodontal Patients". Nutrients 12, n.º 8 (28 de julho de 2020): 2255. http://dx.doi.org/10.3390/nu12082255.

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Background: Periodontal disease is the leading cause of tooth loss worldwide. Current periodontal treatment is limited by its dependency on patients learning and maintaining good dental habits, and repeated visits to oral health physicians. Vitamin C’s role in collagen synthesis and immune function makes it important in wound healing and possibly periodontal healing. Therefore, if some patients are deficient, this may worsen patient outcomes. Methods: Patients were invited to participate following assessment and treatment at the Westmead Centre of Oral Health Periodontic Clinic, regardless of current disease stage or treatment. Adults were eligible if they gave informed consent and had current periodontal disease. Study involvement consisted of periodontal assessment and care followed by an interview and measurement of serum vitamin C and C-reactive protein (CRP). Results: A total of 6 out of 20 patients had vitamin C levels less than the institutional normal range, of whom 2 had levels <11.4 μmol/L and one <28 μmol/L. Low vitamin C was associated with higher periodontal disease stage (p = 0.03). Elevated CRP was found in 2/3 of people with low vitamin C and CRP was negatively correlated with vitamin C (p < 0.01). Vitamin C did not correlate with patient-reported fruit or vegetable consumption, but high processed meat intake was associated with lower vitamin C. Conclusion: Although a small study, this rate of vitamin C deficiency in the periodontal clinic is clinically important and correlations with disease severity and CRP suggests biological importance. This warrants further studies to assess vitamin C and whether supplementation improves periodontal outcomes, particularly in deficient subjects.

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Slamet, Riskiono. "PELAPISAN CABE MERAH DENGAN NANOPARTIKEL KITOSAN UNTUK MENGHAMBAT KEHILANGAN VITAMIN C DAN SUSUT BOBOT". JRSKT - Jurnal Riset Sains dan Kimia Terapan 1, n.º 1 (30 de junho de 2011): 1. http://dx.doi.org/10.21009/jrskt.011.01.

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In this research the possible use of chitosan nanoparticle coating on green peppers (Capsium annuum L) after harvesting and to determined the effect of chitosan nanoparticle coating formulation to control the barrier properties toward water and oxygen.was investigated. Manually green peppers were treated with a solution of 1% ,2% and 3% nanoparticle chitosan and then stored at 200C. The parameters of physcochemical properties such as weight loss and ascorbic acid concentrations, were monitored during storage 4 days until 16 days. Results indicated that the physicochemical properties of weight loss and ascorbic concentration did not show remarkable change during storage period. and the longest storage life 16 The best quality of greeen peppers days were obtained from the chitosan nanoparticle coating at 3% concentration.The results suggest that the biodegradable coating with higher water vapour permeability can be used to maintain the quality and sanitary conditions of freshly harvested green peppers in modified atmosphere packaging. Keywords :chitosan nanoparticle, green pepper, vitamin C, total weight Abstrak Penelitian ini bertujuan untuk menentukan pengaruh konsentrasi nanopartikel kitosan yang terhadap kandungan vitamin C dan susut bobot cabe merah. Cabe merah dilapis dengan larutan nanopartikel kitosan, disimpan pada suhu 200C, dan kandungan vitamin C serta susur bobot diukur setiap 4 hari sekali selama 16 hari. Hasil penelitian menunjukkan bahwa cabe merah yang dilapis dengan larutan yang mengandung nanopartikel kitosan 3%, kehilangan vitamin C sebesar 30% pada hari ke 12, sementara cabe merah yang tidak dilapis, kehilangan vitamin C sebesar 53,8%. Sementara kehilangan susut bobot juga menunjukkan pola yang sama dengan vitamin C. Hasil terbaik diperoleh jika cabe merah dilapis dengan larutan yang mengandung 3% nanopartikel kitosan. kata kunci : nanopartikel kitosan, cabe hijau, vitamin C, jumlah bobot

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Dawn, Indranil, Susmita Sarkar e Chinmoy De. "A comparative study between Antioxidant vitamin and KellgrenLawrence grading scale in knee osteoarthritis patients". Bangladesh Journal of Medical Science 13, n.º 1 (24 de dezembro de 2013): 30–35. http://dx.doi.org/10.3329/bjms.v13i1.14046.

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Osteoarthritis (OA) is a strongly age-related joint disorder that is defined as a gradual loss of articular cartilage. Current concepts of the pathogenic mechanisms of OA suggest that there isa shift in the homeostatic balance between the destruction and synthesis of bone and cartilage,with a net progressive destruction of these tissues. Recent studies of the biology of chondrocytes show that these cells actively produce reactive oxygen species (ROS). ROS are capable of inducing apoptotic cell death in chondrocytes, but more important, they can result in the degradation of aggrecan and collagen. Micronutrient antioxidants such as alpha- Tocopherol (Vitamin E) and Vitamin C also act to reduce the effects of ROS. A hospital based case control study was conducted in Burdwan Medical College, West Bengal, India on 76 postmenopausal women aged 4570 years suffering from Osteoarthritis (OA) of the knee joint, which was diagnosed from symptoms, clinical examinations and radiographic findings. The 151 controls were selected from the healthy persons .plasma vitamin C and serum vitamin E ware measured.. Knee joint radiographs were evaluated with the KellgrenLawrence grading scale .Furthermore both were correlated with KellgrenLawrence grading scale to find out possible association between the antioxidant vitamins and the disease progression. Results showed that there was a significant decrease in antioxidant vitamin levels in patients with knee joint osteoarthritis as compared to the controls suggests that treatment with antioxidants in the initial stages of the disease may be useful as secondary therapy. Both antioxidant vitamins showed negative correlation with KellgrenLawrence grading. Both vitamins decreased with increasing KellgrenLawrence grade. So antioxidant vitamin can be use to assess the disease severity. DOI: http://dx.doi.org/10.3329/bjms.v13i1.14046 Bangladesh Journal of Medical Science Vol. 13 No. 01 January2014: 30-35

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CARR, Anitra C., Terry TIJERINA e Balz FREI. "Vitamin C protects against and reverses specific hypochlorous acid- and chloramine-dependent modifications of low-density lipoprotein". Biochemical Journal 346, n.º 2 (22 de fevereiro de 2000): 491–99. http://dx.doi.org/10.1042/bj3460491.

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Activated phagocytes produce the highly reactive oxidant hypochlorous acid (HOCl) via the myeloperoxidase-catalysed reaction of hydrogen peroxide with chloride ions. HOCl reacts readily with a number of susceptible targets on apolipoprotein B-100 of low-density lipoprotein (LDL), resulting in uncontrolled uptake of HOCl-modified LDL by macrophages. We have investigated the efects of vitamin C (ascorbate), an effective water-soluble antioxidant, on the HOCl- and chloramine-dependent modification of LDL. Co-incubation of vitamin C (25-200 μM) with LDL resulted in concentration-dependent protection against HOCl (25-200 μM)-mediated oxidation of tryptophan and lysine residues, formation of chloramines and increases in the relative electrophoretic mobility of LDL. Vitamin C also partially protected against oxidation of cysteine residues by HOCl, and fully protected against oxidation of these residues by the low-molecular-mass chloramines, Nα-acetyl-lysine chloramine and taurine chloramine, and to a lesser extent monochloramine (each at 25-200 μM). Further, we found that HOCl (25-200 μM)-dependent formation of chloramines on apolipoprotein B-100 was fully reversed by 200 μM vitamin C; however, the loss of lysine residues and increase in relative electrophoretic mobility of LDL were only partially reversed, and the loss of tryptophan and cysteine residues was not reversed. Time-course experiments showed that the reversal by vitamin C of HOCl-dependent modifications became less efficient as the LDL was incubated for up to 4 h at 37 °C. These data show that vitamin C not only protects against, but also reverses, specific HOCl- and chloramine-dependent modifications of LDL. As HOCl-mediated LDL modifications have been strongly implicated in the pathogenesis of atherosclerosis, our data indicate that vitamin C could contribute to the anti-atherogenic defence against HOCl.

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Zang, Qun, David L. Maass, Jean White e Jureta W. Horton. "Cardiac mitochondrial damage and loss of ROS defense after burn injury: the beneficial effects of antioxidant therapy". Journal of Applied Physiology 102, n.º 1 (janeiro de 2007): 103–12. http://dx.doi.org/10.1152/japplphysiol.00359.2006.

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Mechanisms of burn-related cardiac dysfunction may involve defects in mitochondria. This study determined 1) whether burn injury alters myocardial mitochondrial integrity and function; and 2) whether an antioxidant vitamin therapy prevented changes in cardiac mitochondrial function after burn. Sprague-Dawley rats were given a 3° burn over 40% total body surface area and fluid resuscitated. Antioxidant vitamins or vehicle were given to sham and burn rats. Mitochondrial and cytosolic fractions were prepared from heart tissues at several times postburn. In mitochondria, lipid peroxidation was measured to assess oxidative stress, mitochondrial outer membrane damage and cytochrome- c translocation were determined to estimate mitochondrial integrity, and activities of SOD and glutathione peroxidase were examined to evaluate mitochondrial antioxidant defense. Cardiac function was measured by Langendorff model in sham and burn rats given either vitamins or vehicle. Twenty-four hours postburn, mitochondrial outer membrane damage was progressively increased to ∼50%, and cytosolic cytochrome- c gradually accumulated to approximately three times more than that measured in shams, indicating impaired mitochondrial integrity. Maximal decrease of mitochondrial SOD activity occurred 8 h postburn (∼63.5% of shams), whereas maximal decrease in glutathione peroxidase activity persisted 2–24 h postburn (∼60% of shams). In burn animals, lipid peroxidation in cardiac mitochondria increased 30–50%, suggesting burn-induced oxidative stress. Antioxidant vitamin therapy prevented burn-related loss of membrane integrity and antioxidant defense in myocardial mitochondria and prevented cardiac dysfunction. These data suggest that burn-mediated mitochondrial dysfunction and loss of reactive oxygen species defense may play a role in postburn cardiac dysfunction.

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Rozana, Rozana, e Sunardi Sunardi. "MINIMALLY PROCESS PADA BUAH RAMBUTAN DAN PERUBAHAN KANDUNGAN VITAMIN C SELAMA PENYIMPANAN BEKU". Journal of Food Technology and Agroindustry 3, n.º 1 (23 de fevereiro de 2021): 36–44. http://dx.doi.org/10.24929/jfta.v3i1.1247.

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Fresh-cut rambutan products not only have to look fresh, but must have sensory properties (aroma, taste, texture, and visual appeal) similar to fresh products, they must also be safe, healthy and nutritious. So it is necessary to characterize the quality, especially vitamin C from fresh-cut rambutan products which are vacuum packed and stored at frozen temperatures. The purpose of this study was to determine the effect of frozen storage on changes in vitamin C in minimally processed rambutan. The material used in this study was fresh rambutan fruit, Si Kuning variety, obtained from rambutan collectors in Tengguli Village, Sajad District, Sambas Regency. The fruit used is fruit at the ripe stage. The level of vitamin C at the beginning of storage was 14.0772%. The observed peeled rambutan was stored at -15 oC for 20 days, vacuum packed and without vacuum. The results of testing for vitamin C levels were carried out on the 20th day of storage. The level of vitamin C of rambutan after 20 days of storage which was stored at -15 oC decreased drastically when compared to the vitamin C content on day 0. The percentage of loss of vitamin C reached 60% in vacuum packaged rambutan, and the proportion decreased by 70% in non-vacuum packed rambutan.

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