Extraction Of Anthocyanins In Red Purple Tea Leaves And Biological Functions Of Anthocyanins

Anti-tumor, anti-aging, radioresistance and other functions of anthocyanins have been confirmed by recent studies. Presently, extraction and separation of anthocyanins and biological function of anthocyanins has attracted much attention. In this thesis, separation and purification of anthocyanins in red purple tea have been studied. Anti-radical activities of the gradient elution components from effluents of polimide comlumn were measured. The bonding mechanism of pelargonidin, cyanidin-3-O-glucoside to HSA was studied by spectroscopy, respectively. Interaction of pelargonidin, cyaniding-3-O-glucoside with DNA was also investigated.1. Anthocyanin was separated and purified using solvent extraction, column and thin layer chromatography and recrystalization or lead salt precipitation. Anti-hydroxyl radical and anti-superoxide anion radical activities of crude anthocyanin product and the components of other effluents were measured, it showed good activities by them. Averages radical clearance of the five components against two free radicals were 1.4 and 4.5 times of the values for catechin, among which anthocyanin showed a better anti-radical property. Two kinds of high purity of anthocyanin, delphinium-3-O-galactoside, cyanidin-3-O- galactoside,were obtained.2. The interaction of pelargonidin with HSA was studied by fluorescence spectroscopy, UV absorption spectroscopy and synchronous fluorescence spectroscopy. The results showed that pelargonidin could induce an endogenous fluorescence quenching of HSA under a mechanism of static quenching. The quenching rate constants at 25℃, 30℃and 37℃were determined to be 3.36×10⁴,4.29×10⁴ and 4.86×10⁴ L·mol^-1, respectively; the binding constants 3.24×10⁴,4.02×10⁴ and 4.89×10⁴ L·mol^-1, respectively. The number of binding site of the static quenching was calculated. According to the theory of F(?)rster nonradiative energy transfer the interacting distance of pelargonidin and HSA was estimated to be 3.44 nm with an efficiency of 0.0955. By analysis of thermodynamic parameters, the binding of pelargonidin with HSA was mainly attributed to the hydrophobic interaction. The pelargonidin had only slight influence on the HSA conformation by the synchronous fluorescence spectroscopy.3. The interaction of cyaniding-3-O-glucoside with HSA was studied. The results showed that Cy-3-O-Glu could induce an endogenous fluorescence quenching of HSA under a mechanism of static quenching. The quenching rate constants at 25℃and 30℃were determined to be 3.74×10⁴,4.06×10⁴ L·mol^-1, respectively; the binding constants 1.07×105,1.52×10⁵ L·mol^-1, respectively. The number of binding site of the static quenching was calculated. According to the theory of F?rster nonradiative energy transfer the interacting distance of Cy-3-O-Glu and HSA was estimated to be 5.62nm nm with an efficiency of 0.0851. By analysis of thermodynamic parameters, the binding of Cy-3-O-Glu with HSA was mainly attributed to the hydrophobic interaction. The Cy-3-O-Glu had only a slight influence on the HSA conformation by the fluorescence spectra.4. Interaction of pelargonidin and cyaniding-3-O-glucoside with DNA was studied. The binding constants were determined to be 1.54×10⁶,1.16×10⁶ L·mol^-1, respectively.