[Spectrophotomatric determination of antioxidative activity of extractives of Chinese traditional medicine by supercritical fluid CO2 extraction technology].

Applying supercritical CO2 fluid extraction technology, flavonoids were extracted from Chinese traditional medicine asarum heterotropoides, atractylodes macrocephala, and rheum palmatun. Using the method of autoxidation pyrogallol (known as 325 nm method), the superoxide radical scavenging effect of the extraction was carried out in the buffer solution of HCl-tris (pH 8.2). With spectrophotometry, hydroxyl radical created by the system Co2+ + H2O2 in the reaction like Fenton reaction was eliminated by alizarin violet as the color developing agent in the buffer solution HCl-tris (pH 9.0) and the reaction condition was investigated. Result showed that these extractions are elimination agent for these radicals. Asarum heterotropoides is the best of the three.