Effect of ascorbic acid with lipid bilayer of egg-PC (egg yolk phosphatidylcholine).

F. CORRALES CHAHAR; S. B. DIAZ; A. BEN ALTABEF.; C. GERVASI; P. E. ÁLVAREZ

S. M. de Tucumán

Congreso; SAB2012; 2012

SAB

Vitamin C (ascorbic acid) is an essential co-factor for some enzymes, such as those which play a major role in the collagen biosynthesis. Besides, it provides alternative ways to control tumour progressions, infections and inflammation. EggPC liposomes were prepared at 25 ºC (crystalline liquid state) in solutions of ascorbic acid at different concentrations, in order to study the involvement of the main functional groups concerned in the lipid bilayer membrane-solution interaction. Fourier Transformed Infrared (FTIR) and Raman spectroscopy techniques were used. Spectra obtained were analyzed comparatively studying the spectral bands corresponding to the hydrophobic and the interphase regions of the lipid bilayer. The PO2− symmetric and antisymmetric stretching band in eggPC-ascorbic acid systems displayed a similar behaviour to that of eggPC liposomes as shown by FTIR. Moreover, it could be noticed that the two populations of the carbonyl group shows a significant displacement towards higher frequencies as the concentration of ascorbic acid increases. This result suggests that both populations of the carbonyl group lose water without forming H bonds. As shown by FTIR and Raman, the frequency variations of the methyl and methylene groups were not significant.