Comparative Contents of Polyphenolic Compounds in Aerial Parts of Cirsium esculentum, C. serratuloides, and Ancathia igniaria (Asteraceae).

Because Ancathia igniaria (Spreng.) DC. (Cirsium igniarium Spreng.) has been segregated as a monotypic genus from the genus Cirsium on the basis of phylogenetic data, chemotaxonomic differences are of interest to detect in the composition of polyphenolic components of aerial plant parts. Phenolic compounds are of chemotaxonomic significance in a number of genera and families. The polyphenolic profile of aerial parts was therefore compared for Cirsium esculentum (Siev.) C.A. Mey., Cirsium serratuloides (L.) Hill, and A. igniaria. The last two species were for the first time examined in this context. The compounds were identified against known standard via high-performance liquid chromatography (HPLC). The species of the genus Cirsium were found to have similar compositions of simple phenols, but differ in the set of flavonoids. Six to eight phenolic compounds were detected in the species, and three simple polyphenols (syringin, chlorogenic acid, and ethyl gallate) proved to be common. The flavonoid profiles of aerial parts included rutin in both Cirsium species. Cymaroside and quercetin-3-O-ß-D-diglucoside-O-α-L-rhamnoside were species specific for C. serratuloides; salipurposide and hyperoside, for C. esculentum. An extract of A. igniaria aerial parts contained cinaroside (like in C. serratuloides), chrysin 7-O-glucoside, and eriodictyol. A greater difference in flavonoid composition was observed between the genera Cirsium and Ancathia. Data on phenolic compound composition are of importance for chemosystematics and use of plants as medicinal raw materials. The total content of coumarins, aglycones, and flavonoid glycosides in the species was determined by a spectrophotometric method. The contents of flavonoids and coumarins in C. esculentum and C. serratuloides were comparable and exceeded their contents in A. igniaria. Thus, A. igniaria proved to differ from the genus Cirsium in the quantitative and qualitative composition of phenolic compounds.

Numerical simulations of stochastic circulatory models.

Properties of two of the stochastic circulatory models theoretically introduced by Smith et al., 1997, Bull. Math. Biol. 59, 1-22 were investigated. The models assumed the gamma distribution of the cycle time under either the geometric or Poisson elimination scheme. The reason for selecting these models was the fact that the probability density functions of the residence time of these models are formally similar to those of the Bateman and gamma-like function models, i.e., the two common deterministic models. Using published data, the analytical forms of the probability density functions of the residence time and the distributions of the simulated values of the residence time were determined on the basis of the deterministic models and the stochastic circulatory models, respectively. The Kolmogorov-Smirnov test revealed that even for 1000 xenobiotic particles, i.e., a relatively small number if the particles imply drug molecules, the probability density functions of the residence time based on the deterministic models closely matched the distributions of the simulated values of the residence time obtained on the basis of the stochastic circulatory models, provided that parameters of the latter models fulfilled selected conditions.