RESUMO
Microbiota decussata Kom. (Cupressaceae) is a subalpine species endemic to the Sikhote Alin Mountains with populations scattered throughout the range. We used sequence data for four noncoding regions of chloroplast DNA to characterize the genetic diversity in populations sampled from different parts of M. decussata natural range. No variation was observed in the trnT-trnF region, whereas the trnH-psbA, trnS-trnfM, and trnS-trnG regions showed polymorphisms. At the species level, we found a low nucleotide diversity (pi = 0.0009) and high haplotype diversity (h = 0.981) as well as high differentiation (Phi(ST) = 0.420). N(ST) and G(ST) values suggested the existence of a phylogeographic structure in M. decussata. The observed patterns of diversity could be explained in part by ecological features of the species and its long-term persistence throughout the range with population expansion, successive fragmentation and isolation.
Assuntos
Cupressaceae/genética , Variação Genética , Genomas de Plastídeos/genética , Filogenia , Análise de Variância , Sequência de Bases , Primers do DNA/genética , Demografia , Geografia , Haplótipos/genética , Dados de Sequência Molecular , Federação Russa , Análise de Sequência de DNARESUMO
Seven eremophilane-type sesquiterpene glucosides, alticolosides A-G, have been isolated from aerial parts of the endemic Far Eastern species Ligularia alticola Worosch. (Family Asteraceae) along with two known compounds, monoterpenoid glycoside (4S)-α-terpineol 8-O-ß-D-glucopyranoside and norditerpenoid glycoside 7(8)-dihydro-ß-ionone 3-O-ß-D-glucopyranoside. Alticoloside D was identified with the earlier known 8-O-(ß-D-glucopyranosyl)-2-oxo-eremophila-1(10),8,11-triene, but the stereostructure of the latter was revised on the basis of ROESY and CD data. All the glycosides are derivatives of new eremophilane-type aglycones, differing from known eremophilanes in details of planar and/or stereo structures except for the aglycone of alticoloside E.