Safety assessment of Guibi-tang: Subchronic toxicity study in Crl:CD SD rats

Guibi-tang (Kihi-To in Japanese and Qui-Pi-Tang in Chinese) is a multiherbal traditional Korean medicinal formula used for treatment of amnesia, fatigue, poor memory or forgetfulness, anemia, insomnia, and necrosis. The aim of the present study was to investigate potential safety, if any, of subchronic administration of Guibi-tang aqueous extract (GBT) in laboratory animals. For this study, 0, 1000, 2000, and 5000 mg/kg/day of GBT was administered to Crl:CD Sprague Dawley rats (10/sex/group) for 13 weeks via oral gavage. Administration of the GBT did not result in any mortality, body weight, food consumption, hematology, serum biochemistry, clinical or ophthalmological signs or changes in urinalysis, gross findings, or organ weight. However, histopathology revealed forestomach hyperplasia and duodenum mucosal hyperplasia in rats of both sexes at the highest dose of GBT, 5000 mg/kg/day. Therefore, the no-observed-adverse-effect level in rats was established for GBT at 2000 mg/kg/day under the conditions of this study.

Acute toxicity and genotoxicity study of fermented traditional herb formula Guibi-tang

ETHNOPHARMACOLOGY RELEVANCE

Guibi-tang (Guipi-tang in Chinese and Kihi-to in Japanese) is a multi-herb traditional medicine commonly prescribed to treat psychoneurosis in East Asia. Although this medicine has been widely used, there is little available information on the safety and toxicity of Guibi-tang, especially on the fermented one.

MATERIALS AND METHODS

Guibi-tang, composed of 12 herbs, was fermented with bacteria and lyophilized. Single dose acute toxicity in rats was observed for 14 days after administration. Genetic toxicity of fermented Guibi-tang was evaluated on bacterial reverse mutation in Salmonella and Escherichia spp., chromosome aberrations in Chinese hamster ovary cells, and micronucleus formation in mice. Ingredients in FGBT were identified and quantified by high performance liquid chromatography-mass spectrometry.

RESULTS

In acute oral toxicity study, behavior, clinical signs and body weight changes were normal observing in all experimental animals. No revertant colonies were found in any bacterial cultures examined. Morphological or numerical anomalies and significant increased number of aberrant metaphases were not observed. Micronucleus assay showed no significant increases in the frequency of inducing micronuclei in any dose examined. Decursinol, decursin, glycyrrhizin, and 6-gingerol in fermented Guibi-tang were identified and quantitated. As a whole, no acute and genotoxic effects were found in all the assays and parameters analyzed.

CONCLUSION

Fermented Guibi-tang was recognized as safe and non-toxic, and therefore can be used for applications of traditional medicine in modern complementary and alternative therapeutics and health care.