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1.
Plants (Basel) ; 12(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37631188

RESUMO

Plants in high-altitude habitats are exposed to severe environmental stressors, including extreme temperatures and irradiation, which can have wide-ranging effects on changes of secondary-metabolite profiles in higher plants. Altitude-related variation of levels of polyphenols in organs of medicinal and food plant species has not yet been investigated sufficiently. This study was focused on variation in quantitative profiles of classes and of individual biologically active phenolic compounds in leaf extracts of resource species Spiraea chamaedryfolia and Spiraea media from the family Rosaceae in coenopopulations of the Altai Mountains, along an altitudinal gradient. High-performance liquid chromatography revealed 22 polyphenolic compounds in the extracts of S. media leaves, with the main polyphenolic compounds being flavonols. Sixteen compounds were found in S. chamaedryfolia leaf extracts, and the major ones were flavonols and a flavanone. Opposite responses to changes in the altitude-associated growth conditions were documented for levels of some individual polyphenolic compounds. With an increase in altitude, concentrations of chlorogenic acid and of flavanone in the extracts of S. chamaedryfolia leaves significantly increased, while concentrations of cinnamic acid, astragalin, and kaempferol diminished. A statistically significant positive correlation between the altitude of plant habitats and total levels of polyphenols and phenolcarboxylic acids was detected. In leaf extracts from S. media, an altitude increase was significantly positively correlated with astragalin, avicularin, and cinnamic acid levels and negatively correlated with hyperoside concentration.

2.
Biology (Basel) ; 10(12)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34943186

RESUMO

(1) Background: The way tobacco and tea spread among virgin populations is of major interest our understanding of how ancient economic and cultural practices could have influenced current habits. (2) Methods: hair concentrations of theobromine, theophylline, caffeine, nicotine, and cotinine were measured in hair samples from 47 frozen bodies of people from eastern Siberia, dated from the contact with Europeans to the assimilation of people into Russian society. (3) Results: hair concentration of theobromine, theophylline, and caffeine vary with the type of beverage consumed: green, black, or local herbal teas. Shortly after the first contacts, a few heavy consumers of tobacco were found among light or passive consumers. Tobacco-related co-morbidities began to be recorded one century after and heavy tea users were only found from the 19th century (4) Conclusions: Economic factors and social and family contacts seem to have played a decisive role in tobacco consumption very early on. Behavioral evolution governed the process of substance integration into Siberian culture and was a determinant for the continuity of its use across long periods of time. Analyzing the respective contributions of social and economic processes in the use of these substances opens avenues of investigation for today's public health.

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