Ecological–Cenotic, Chemosystematic, and Pharmacognostic Features of Wormwood from the Species Artemisia Obtusiloba Ledeb. in Southern Siberia

Abstract

In the mountain steppes of Altai, Sayan, Tuva, and the Baikal region, large-bush wormwoods with a powerfully developed lignified caudex, a bunch of branched shoots from the base, are of the utmost importance. These are subshrub wormwoods: Artemisia obtusiloba, Artemisia altaica, Artemisia martjanovii, and Artemisia subviscosa. In the Altai Mountains and southwestern Tuva, Artemisia obtusiloba and Artemisia altaica are typical. Artemisia martjanovii is known from the foothills of the Sayan Mountains: in the steppes of the Minusinsk Basin and the Abakan forest–steppe. A. subviscosa is found in the northeastern part of the Baikal region: its largest massif is located in the central and upper sections of the Barguzin valley. The ecological and cenotic features of these related wormwoods, belonging to the Absinthium section of the subgenus of true wormwoods, in the contrasting conditions of the mountains of Southern Siberia have noticeable differences in morphology and ecology from the cryoxerophytic Altai–West Tuvan A. obtusiloba and A. altaica, the mesoxerophytic A. martjanovii in Khakassia, and the xerophytic A. subviscosa in the Baikal region. In addition to the classical morphological diagnostic features in the structure of leaves and inflorescences, which are variable and complicate the diagnosis of taxa, the phytochemical criterion was taken into account with the identification of the component composition of essential oil using modern methods of spectral analysis. As a result, the greatest degree of similarity of the composition of compounds in the metabolites of Artemisia obtusa and Artemisia altaisis was established, thereby confirming the subspecies status of Artemisia altaisis from A. obtusiloba, which was first substantiated by I.M. Krasnoborov (1997). At the level of independent species, taking into account both morphological characteristics, especially in the structure of the inflorescence (involucres and receptacle), and phytochemical indicators, Artemisia martjanovii and Artemisia subviscosa are substantiated. Wormwoods have important resource value as medicinal plants. A wide variety of components has been found in the essential oil of the studied wormwoods, many of which are pharmacologically very valuable. For example, detailed analysis and pharmacognostic studies of A. subviscosa yielded positive results on the richness and diversity of biologically active substances; in addition to turpentines, the content of flavonoids, coumarins, and tannins was found.