ANTIMUTAGENIC STUDIES WITH L-ASCORBIC ACID AND GREEN TEA EXTRACT BY MEANS OF THE AMES TEST

PONTORIERO, A.; HURE, E.; MONTI, L.; MOSCONI, N.; RIZZOTTO, M.

BIOCELL

INST HISTOL EMBRIOL-CONICET

Lugar: Mendoza; Año: 2010 vol. 34 p. 79 - 79

0327-9545

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES-AR;} a:link, span.MsoHyperlink {color:blue; text-decoration:underline; text-underline:single;} a:visited, span.MsoHyperlinkFollowed {color:purple; text-decoration:underline; text-underline:single;} @page Section1 {size:595.3pt 841.9pt; margin:6.0cm 184.3pt 331.7pt 6.0cm; mso-header-margin:35.45pt; mso-footer-margin:35.45pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> ANTIMUTAGENIC STUDIES WITH L-ASCORBIC ACID AND GREEN TEA EXTRACT BY MEANS OF THE AMES TEST Pontoriero, Ana; Hure, Estela; Monti, Laura; Mosconi, Natalia; Rizzotto, Marcela* Área Inorgánica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Suipacha 531, 2000 Rosario  E-mail: rizzotto@iquir-conicet.gov.ar   N-nitroso compounds are a class of widely distribute mutagens. They can be formed in vivo due to the reaction between amides and amines and nitrite. L-ascorbic acid (Asc.) and green tea polyphenols can react with nitrite diminishing or removing the nitrosation risk. According to the Ames test a compound would be a mutagen if the reversion coefficient, R.C. (R.C.: revertant number per tested plate/revertant number per control plate) is ≥ 2. In the present work we proved the chemopreventive action of L-ascorbic acid and green tea aqueous extracts as antimutagens (AM) on the mutagenicity of a constant dose of a reaction mixture (RM) formed by sodium sulfathiazole and nitrite. Variable doses of L-ascorbic acid were tested (580-5800 nmol/plate and 5.8-58 nmol/plate). The % of inhibition was calculated with the following equation: % inh. = [(CRwithout AM - CRwith AM)/ (CRwithout AM - 1)] ·100. Working with TA98 strain it was obtained a 34% of inhibition in the minor range and 100% of inhibition in the major range of Asc. Also, five doses of green tea were tested (between 10 and 100 µL/plate) and it was found 100% of inhibition in all of them. Previous experiences of antimutagenic effect of L-ascorbic acid against 4-Nitro-o-phenylenediamine (4-NOPD) was deepen, founding that it would be a 100% of inhibition if [L-ascorbic acid]0/ [4-NOPD]0 = 8. The excess of Asc. required for RC = 1 probably would be due to an incomplete displacement of reaction.