The Flow Injection Chemiluminescence Analysis Of The Antioxidant Activity Of Flavonoids In The Natural Product

This thesis determined the total content and antioxidation of flavonoids in natural product . measured the total content of flavonoids by ultraviolet spectrometry photometry, at the same time, studied out new flow-injection chemiluminescence method of 1,10-phenanthroline—cuprous ion—hydrogen peroxide—carbonate buffer solution system , the antioxidation of flavonoids was determined by this method. And discussed the relationship between the total content and antioxidation of flavonoids.Firstly this thesis selected the optimum conditions of flavonoids extraction by supersonic method, ethanol as solvent, ethanol concentration 95%, extraction temperature 0℃, oscillation time 10 min, oscillation 3 times. Then extracted flavonoids of hawthorn, locusttree, marigold and cockscomb series samples in this condition, and determined the total content of flavonoids by ultraviolet spectrometry photometry. The result showed that each samples had plentiful flavonoids, and the sequence of the total content of flavonoids: leaf of hawthorn>leaf of crataegus pinnatifida>hawthorn>crataegus pinnatifida; bud of Chinese scholartree>flower of Chinese scholartree>leaf of Chinese scholartree>stem of Chinese scholartree; flower of marigold>leaf of marigold>root of marigold>steam of marigold; leaf of cockscomb>fiower of cockscomb>steam of cockscomb. The optimum conditions of the new flow-injection chemiluminescence method were investigated by examining the influence of various factors. The optimum conditions are carbonate buffer solution pH 10.57, H₂O₂ concentration 0.27 mol/L, Cu⁺ concentration 1.0.×10^-4 mol/L, 1,10-phenanthroline concentration 4.0×10^-4mol/L, velocity2. 5 mL/min. The antioxidation of rutin, quercetin and morin were determined by this method, the result showed that IC₅₀ were separately 2.22 μg/mL, 2.24 μg/mL and 76μg/mL, the sequence of antioxidation: rutin>quercetin>morin. The antioxidation of hawthorn, locusttree, marigold and cockscomb series samples were also determined by this method, the sequence of antioxidation: leaf of...