Abstract
In this study, we carried out the preparing standardization and regulation of processed Glycyrrhizae Radix (PGR) which have been widely used in oriental medicines. Glycyrrhizae Radix(GR) have been generally prepared by the stir-frying, or mix-frying with honey for the purpose of decreasing sweetness and augmenting vitality. Firstly, we tried to standardize PGR prepared by the stir-frying. We purchased 14 kinds of PGR and non-processed GR(NPGR) at oriental physician's offices and oriental pharmacies on a nation scale, respectively. The amounts of dry on loss, water extract, diluted ethanol extract, ether extract, total ash, acid insoluble ash, glycyrrhizin(GL), glycyrrhetic acid(GA) and liquiritin(LQ) of them were examined. The amounts of dry on loss, GL and LQ in commercial PGRs showed remarkable decrease, while GA showed increased as compared with NPGR. In order to standardize preparing method of PGR, the effect of heating time on physico-chemical parameters and biological activities were examined. Physico-chemical parameters such as dry on loss, extract amount, GL and LQ contents in PGRs showed decrease, however, GA was increased with heating time as compared with NPGR. Also, GA, obtained from heat-treated GR, was found as an artifact in PGRs. PGR was more effective than NPGA in vitro test of DPPH scavenging effect and TBA-Rs reducing effect. PGR and NPGR showed potent hepatoprotective effect on $CCl_4-intoxicated$ rats. Especially, PGR prepared by 80 min of heating was the most effective. Considering these results, the optimal condition for PGR preparation was $150^{\circ}C$ for 80 min.
