Studies on extraction and in vitro anti-urolithic effect of the prescription ngu linh gia vi

Dried powder extraction: Among the components of the traditional oriental prescription “Ngu linh gia vi”, rhizoma Atractylodis macrocephalae, Polia, Polyporus, rhizoma Alismatis and cortex Cinnamomi were extracted with ethanol 80%; the others were extracted with boiled water. All the extracts were mixed with rhizoma Dioscoreae persimilis powder, then dried in vacuum. The total yield of the dried extract was 7.7% compared with the plant materials. Anti-urolithic effect: In vitro studies showed that the percentages of worn stones were respectively 0.92% (control group), 18.94% (low dose of dried extract group), and 19.97% (high dose of dried extract group).