961 12 4130 3 11526 document 4130 20036425 application/xml cb20f6e22498debb0a061b80eca46c22 MD5 76348 2014-02-11 07:49:50 http://eprints.iliauni.edu.ge/961/1/20036425 961 1 1 application/xml text ge public

20036425

published archive 105 disk0/00/00/09/61 2014-02-11 08:33:47 2014-02-11 08:33:47 2014-02-11 08:33:47 article show Metreveli Nunu nunu_metreveli@iliauni.edu.ge Jariashvili Ketevan Namicheishvili Louisa Svintradzea David Chikvaidze Eduard Sionkowska Alina Skopinska Joanna pub QC QH301 ins14 public The influence of deleterious UV radiation on collagen molecules in the absence and presence of ascorbic acid using UV–vis and FT-IR spectroscopy has been studied. Intensity of UV–vis absorption spectrum of collagen with a maximum at 275 nm due to the aromatic residues (tyrosine and phenylalanine) increases with the increasing dose of UV radiation. This effect is significantly hindered in the presence of antioxidant ascorbic acid. Intensities of FT-IR bands (amide A, B, I and II) of collagen decrease with the increase of the UV radiation dosage. Intensities of bands are also decreased in the presence of ascorbic acid. Results suggest that increasing the concentration of ascorbic acid increases the photo-stability of collagen, and the collagen becomes less sensitive to UV radiation. It is possible that hydrogen bonds form between the groups N–H of collagen and C=O of ascorbic acid. It is believed that under UV radiation free radicals appear in acid soluble collagen and resulting in photodegradation of the macromolecule restore due to the ability of ascorbic acid donating one or two electrons. Increasing the dose of radiation causes more molecules of ascorbic acid to slow down, and their antioxidant effect is diminished accordingly. 2010-03 published Ecotoxicology and Environmental Safety 73 3 Elsevier 448-455 10.1016/j.ecoenv.2009.12.005 TRUE