Objective: To compare changes of chemical composition and efficacy before and after Phytolaccae Radix processing with vinegar. Method: Phytolaccae Radix was processed by according to vinegar processing method in the 2010 edition of ‘Chinese Pharmacopoeia’.The content of total saponins was dtermined by sulfuric acid-vanillin colorimetry;The content of esculentoside A was determined by HPLC-ELSD

chromatographic conditions were:Lichrospher-C18 column(4.6 mm×250 mm

5 μm)

mobile phase of methanol-0.4% acetic acid(65:35)

flow rate 1.0 mL·min-1

column temperature 40 ℃

injection volume 20 μL;ELSD conditions were:drift tube temperature 90 ℃

flow rate of carrier gas 2.5 L·min-1.SD rats were randomly divided into normal saline group

positive drug group (hydrochlorothiazide)

crude and processed Phytolaccae Radix group

brine loading model formed with saline

then we observed urine of rats within 5 hours by metabolic cage method.ICR mice were randomly divided into normal saline group

positive drug group (mirabilite)

crude and processed Phytolaccae Radix group

then we compared small intestinal propulsive rate between crude and processed Phytolaccae Radix by ink propulsion method. Result: After processing of Phytolaccae Radix with vinegar

the content of total saponins increased from 1.66% to 1.91%

the content of esculentoside A increased from 0.64% to 0.82%

diuretic efficacy on rats enhanced and purgative efficacy on mice moderated. Conclusion: After being processed with vinegar

the content of total saponins and esculentoside A both increased

diuretic efficacy enhanced and purgative efficacy moderated.