Biologically active substances of Rhei tangutici radices and Rhei rhabarbari radices

The results of the comparative analysis of the qualitative composition and quantitative content of anthracene derivatives equivalent to istizin in Rhei tangutici radices, collected in Central aimak (Mongolia) and Rhei rhabarbari radices collected in Buryatia (Russia) using spectrophotometry method, are presented in the article. Anthracene derivatives (emodins, methyl chrysazin), tannins, flavonoids, coumarins and fatty oils were qualitatively detected in all samples (using standart methods). The content of anthracene derivatives in R. tangutici radices (2,2-3,0%) meets the standards of State Pharmacopoeia (not less than 2%), and R. rhabarbari radices fails to meet the requiremetns. (0.5-1.1%).