Study On Chemical Constituents Of Male Anthotaxy Of Populus Tomentosa Carr.

Extraction and purification of natural products from Chinese traditionalmedicine are not only key steps of rational combination, pharmacology andmolecule structure identification, but also important for Chinese medicinedevelopment. In this study, we firstly tested the antioxidant effects of theextract of male anthotaxy of Populus tomentosa Carr. and then extracted,purified and identified the compounds. The main results are as follows:1. The effects of the extract of male anthotaxy of Populus tomentosa Carr.on eliminating active oxygen species in some modified chemical systems wereinvestigated by chemiluminescence and spectrophotometry. The results showthat the extract could efficiently eliminated O₂^·-, ·OH, H₂O₂,DPPH·andthe 50% inhibition concentration (IC50) was 0.217,0.606,0.061,and 0.068mg/ml, respectively.2.Comparing different extraction methods including alcohol extraction,supercritical CO₂ extraction and ultrasonic-assisted extraction, the resultsshowed that ultrasonic-assisted extraction was optimized. The optimumextracting conditions of flavonoids are investigated by using orthogonalexperimental design. The results show that 150W ultrasonic wave, 30∶1 of70 % ethanol to male inflorescence weight, extraction for 40min are optimal.This method is more effective with advantages of short extracting period,higher yield and lower extracting temperature.3. The alcohol extract was extracted by light petroleum (b.p. 60–90 °C) andethyl acetate successively which yielded 70 g of light petroleum extract and100 g of ethyl acetate extract. The light petroleum extract was furthersubjected to silica gel chromatography and two compounds were obtained.The ethyl acetate extract was further subjected to silica gel chromatography byeluting stepwise with chloroform-methanol (97:3, 90:10, 80:20 and 70:30, v/v)to obtain four fractions. These fractions were isolated and purified by HSCCC...