Preliminary results of spectrophotometric screening of secondary metabolites accumulation in lichen thalloms

Abstract

This paper discusses the influence of biotopic conditions on the secondary compounds accumulation in lichen thalloms. Secondary metabolites inherent in the metabolism of various groups of organisms are widely represented in symbiotic organisms lichens, with a significant number of these compounds being phenolic derivatives. The authors of the paper present the results of spectrophotometric scanning of alcohol extracts from lichen thalloms of three species: Xanthoria parietina (L.) Belt., Parmelia sulcata Tayl., Vulpicida pinastri (Scop.) J.-E. Mattsson M.J. Lai, sampled in different forest communities of the Krasnosamarsky forest (Samara Region), in 9 plots, where plant communities were fragments of natural forests (birch, aspen, linden, oak) and forest stands. Forest communities differed in their position in the relief, the composition of the arboreal stage, associated with the height and closeness of the plantations to microclimate conditions. The extracts obtained by infusion of 96% ethanol samples were analyzed using the AZURA UV / VIS UVD 2.1 L detector (190750 nm, Knauer) in the laboratory of Chemistry Department of Samara University to obtain absorption spectra in the UV region using the ClarityChrom program. The study can be considered as an initial stage of bioecological screening, which makes it possible to ascertain the dependence of the secondary metabolites accumulation on habitat parameters in relation to the conditions of forest ecosystems in different parts of the Samara Region. The spectrophotometric study of the extracts demonstrated the presence of species-specific features of the spectra, indicating the differences in the qualitative composition of the extracts. For extracts obtained from samples of lichens were found spectra differences: quantitative for all the species, and also qualitative for Xanthoria parietina and Vulpicida pinastri extracts, related to qualitative and quantitative differences in the accumulation of secondary metabolites. These differences are presumably associated with differences in the biotopic conditions of growth of the thalli of the three studied lichen species.