Optimization extraction on ultrasonic technology of total phenols in leaves of Populus canadensis Moench

The single factor test and the orthogonal experimental design were carried out to optimize the extraction technology of total phenols from leaves of Populus canadensis Moench..The result indicated that ethanol concentration,the ratio of solvent to material and the extraction temperature had a remarkable influence on the extraction of total phenols,while the extraction time had hardly influence on it.Extracted twice using 70% ethanol as extraction solvent,the optimal extraction technology of total phenols is 40∶1 of the ratio of solvent to material、 55 ℃ of temperature、 and 10 min of extracting time.By above extraction technology,total phenols content was 1.43 %.The optimized technology had good reproducibility and high precision.