Effect of ascorbic acid on incidence of spontaneous mammary tumors and UV-light-induced skin tumors in mice

1991 ◽  
Vol 54 (6) ◽  
pp. 1252S-1255S ◽  
Author(s):  
L Pauling
2020 ◽  
Vol 90 (5-6) ◽  
pp. 439-447 ◽  
Author(s):  
Andrew Hadinata Lie ◽  
Maria V Chandra-Hioe ◽  
Jayashree Arcot

Abstract. The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%–26% and 48%–76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.


2007 ◽  
Vol 84 (3) ◽  
pp. 537-543 ◽  
Author(s):  
Kazuhiro Tokuda ◽  
Charles F. Zorumski ◽  
Yukitoshi Izumi

1985 ◽  
Vol 48 (2) ◽  
pp. 112-117 ◽  
Author(s):  
ANTHONY J. FANELLI ◽  
JOAN V. BURLEW ◽  
MINA K. GABRIEL

The effectiveness of visible and UV light screens, compounded in polyethylene dairy resin to protect vitamins in milk from photodegradation, was investigated. Three pigments and three UV absorbers were chosen for testing on the basis of their commercial availability, FDA approval for contact with food, and advertised compatibility with polyolefins. In this study, vitamin decomposition was accelerated over what would be experienced in a commercial milk container in order to expedite the testing program and exaggerate differences in effectiveness of the various light screens. Good protection of vitamin A and riboflavin was provided by 0.3 wt % FD&C yellow #5. Protection of ascorbic acid was marginal. Two of the UV absorbers, Cyasorb 531 and Tinuvin 326, afforded protection of vitamin A, but not riboflavin or ascorbic acid. Visible and UV spectra are presented for the vitamins and light screens used in this work.


Genes ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 238 ◽  
Author(s):  
Junko Maeda ◽  
Allison J. Allum ◽  
Jacob T. Mussallem ◽  
Coral E. Froning ◽  
Alexis H. Haskins ◽  
...  

Ascorbic acid 2-glucoside (AA2G), glucosylated ascorbic acid (AA), has superior properties for bioavailability and stability compared to AA. Although AA2G has shown radioprotective properties similar to AA, effects for UV light, especially UVC and UVB, are not studied. AA2G was tested for cytotoxicity and protective effects against ionizing radiation, UVC, and broadband and narrowband UVB in Chinese hamster ovary (CHO) cells and compared to AA and dimethyl sulfoxide (DMSO). Pretreatment with DMSO, AA, and AA2G showed comparative protective effects in CHO wild type and radiosensitive xrs5 cells for cell death against ionizing radiation with reducing the number of radiation-induced DNA damages. Pretreatment with AA and AA2G protected CHO wild type and UV sensitive UV135 cells from UVC and broadband UV, but not from narrowband UVB. DMSO showed no protective effects against tested UV. The UV filtration effects of AA and AA2G were analyzed with a spectrometer and spectroradiometer. AA and AA2G blocked UVC and reduced short wavelengths of UVB, but had no effect on wavelengths above 300 nm. These results suggest that AA2G protects cells from radiation by acting as a radical scavenger to reduce initial DNA damage, as well as protecting cells from certain UVB wavelengths by filtration.


2014 ◽  
Vol 77 (6) ◽  
pp. 963-971 ◽  
Author(s):  
YAN ZHU ◽  
TATIANA KOUTCHMA ◽  
KEITH WARRINER ◽  
TING ZHOU

This study evaluated three UVC wavelengths (222, 254, and 282 nm) to degrade patulin introduced into apple juice or apple cider. The average UV fluences of 19.6, 84.3, 55.0, and 36.6 mJ·cm−2 achieved through exposure to UV lamps at 222-, 254-, and 282-nm wavelengths and the combination of these wavelengths, respectively, resulted in 90% reduction of patulin in apple juice. Therefore, the order of efficiency of the three wavelength lamps was as follows: far UVC (222 nm) &gt; far UVC plus (282 nm) &gt; UVC (254 nm). In terms of color, treatment of apple juice with 222 nm resulted in an increase in the L* (lightness) value but decreases in a* (redness) and b* (yellowness) values, although the changes were insignificantly different from the values for nontreated controls based on a sensory evaluation. The ascorbic acid loss in juice treated at 222 nm to support 90% reduction of patulin was 36.5%, compared with ascorbic acid losses of 45.3 and 36.1% in samples treated at 254 and 282 nm, respectively. The current work demonstrated that the 222-nm wavelength possesses the highest efficiency for patulin reduction in apple juice when compared with the reductions by 254 and 282 nm, with no benefit gained from using a combination of wavelengths.


2005 ◽  
Vol 7 (3) ◽  
Author(s):  
M Waheed Roomi ◽  
Nusrath W Roomi ◽  
Vadim Ivanov ◽  
Tatiana Kalinovsky ◽  
Aleksandra Niedzwiecki ◽  
...  

Author(s):  
Geovanni Dantas Cassali ◽  
Cecília Bonolo de Campos ◽  
Angélica Cavalheiro Bertagnolli ◽  
Alessandra Estrela-Lima ◽  
Gleidice Eunice Lavalle ◽  
...  

Mammary neoplasms are described as the third most common type of feline tumor, after haematopoietic and skin tumors, and present a challenge for clinicians because the prognosis for feline mammary tumors ranges from guarded to poor. Thus, it is necessary to define new therapeutic approaches and establish more in-depth knowledge about this disease in felines. The main aspects of the diagnosis, prognosis and treatment of feline mammary neoplasia were discussed, aiming to standardize the criteria and to serve as a guide for pathologists and veterinary clinicians.


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