65271-60-5Relevant academic research and scientific papers
Gallic acid induced dose dependent inhibition of lysozyme fibrillation
Konar, Mouli,Bag, Sudipta,Roy, Pritam,Dasgupta, Swagata
, p. 1224 - 1231 (2017/06/13)
Amyloidosis is primarily characterized by the deposition of misfolded protein aggregates. Although the natural polyphenols have long been known as effective amyloid inhibitors, the mechanistic details of their inhibitory actions still remain unclear. Our present study explores the inhibition mechanism of polyphenols by studying the anti-amyloidogenic property of gallic acid (GA), the smallest structural unit of tea polyphenols, on hen egg white lysozyme (HEWL) at physiological pH. Using various spectroscopic techniques such as UV-vis, fluorescence, circular dichroism and dynamic light scattering, and microscopic techniques such as TEM and FESEM, it has been shown that GA potentially inhibits the self-aggregation process in a concentration dependent manner. Gel electrophoresis studies suggest that the o-dihydroxy moiety of GA is oxidized into the quinone moiety and H2O2 in the system under the experimental conditions. The quinone binds near the hydrophobic region of HEWL and restricts hydrophobic exposure. Cyclic voltammetry studies reveal that the Met residues of HEWL are oxidized by H2O2 to highly polar sulfoxide-modified side chains. The partially unfolded intermediates formed under the denaturing conditions employed remain in contact with the solvent thus preventing further aggregation.
Temperature Oscillations in Bromate-Gallic Acid System: A Calorimetric Study
Mukherjee, Kallol,Moulik, S. P.,Mukherjee, D. C.
, p. 561 - 568 (2007/10/02)
The oscillatory reaction between potassium bromate and gallic acid in sulfuric acid medium has been studied calorimetrically with and without ferroin indicator.Enthalpy changes during oscillations have increased with increasing bromate concentration in presence and absence of the indicator.Prominent catalytic activity of the indicator has been observed.An initial large enthalpy change has been observed in both uncatalyzed and catalyzed conditions prior to the starting of oscillation.Attempts have been made to correlate the main thermal events with the proposed mechanism of the reaction.
Kinetic Study of the Initial Phase of the Uncatalised Oscillatory Reaction of Potassium Bromate and Gallic Acid
Jwo, Jing-Jer,Chang, Eng-Fen
, p. 2388 - 2392 (2007/10/02)
Under suitable conditions, the uncatalyzed oxidation of gallic acid(GA) by bromate ion can exhibit damped oscillations in bromide ion concentration and color.The characteristic of oscillations depend on the concentrations of gallic acid, bromate ion, and sulfuric acid as well as on temperature.Extensitive study is made for obtaining the scope of this oscillating reaction.The observed rate law obtained with GA in great excess is d->/dt=k+>2-> with k=(3.17+/-0.19)E-2 M-3 s-1 at 25 deg C for 0=(0.400-2.00)M.The activation parameters ΔH* and ΔS* are 64.4+/-1.0 kJ/mol and -57.6+/-0.8 J/(mol K), respectively.Product analysis shows that bromination and decarboxylation reactions also take place during oscillations.
