ABSTRACT
OBJECTIVE:To observe the ultra-filtration and the resistance to pollution of5ultra-filtrated membrane in respect of each of the compositions from the Isatis indigotica Fort.water-extraction,in order to produce the Isatis indigotica Fort.-preparation through ultra-filtrated method instead of ethanol-sedimentary method.METHODS:By measuring the quantities of the solid residue and the contents of polysaccharide,arginine and chloroform extraction in the ethanol-sedi?mentary solution and ultra-filtrated solution by gravimetry,TLC-scan and HPLC respectively.RESULTS:The solid residue in the ultra-filtered solution was lower than that in the ethanol-sedimentary solution;The content of polysaccharide in the ultra-filtered solution with polypropylene nitrile membrane and polysulfone-6000membrane were close to that in the ethanol-sedimentary solution.The arginine in the ultra-filtered solution was higher than that in the ethanol-sedimentary solution,but the chloroform extraction in the ultra-filtered solution was lower than that in ethanol-sedimentary solution;The resistance to pollution of polysulfone membrane was the strongest in these ultra-filtrated membrane.CONCLUSION:According to the requirement for isolation of active components,ultra-filtrated method with polysulfone-50000membrane could be used instead of ethanol-sedimentary method for efficient and economical application.