This paper presents a vacuum-cavitated extraction method for glycyrrhizic acid(GA) extraction from supercritical extraction residue.The optimum extraction conditions are as follows:0.3% ammonia solution as the solvent,the ratio of solvent to solid 10∶[KG-*3/5]1(mL/g),vacuum-cavitated time 15 min,and the crude (extract) yeild is 30.3%,in which the content of GA is 6.6%,so the GA extraction yeild is 2.0%.There are three extraction methods:soxhlet,ultrasonic wave,and vacuum-cavitated extraction methods.The results show that the extraction yield of GA by vacuum-cavitated extraction method is 1.6 times that by soxhlet extraction method and 1.2 times that by ultrasonic.At the same time,the vacuum-cavitated extraction method shows many advantages,including lower temperature,less solvent,shorter extraction time,higher extraction yield,and higher GA content in the crude extract.The vacuum-cavitated extraction method is new and highly(efficient),which can be utilized in the pharmaceutical industry.
