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Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems
RESEARCH ARTICLE

Importance of phenolics in populations of Teucrium chamaedrys (Lamiaceae) from serpentine soils

Miroslava Zhiponova https://orcid.org/0000-0001-7333-6558 A D * , Zhenya Yordanova A * , Dolja Pavlova B , Mariya Rogova A , Milena Dimitrova A , Daniela Dragolova A , Elena Tasheva-Terzieva C and Veneta Kapchina-Toteva A
+ Author Affiliations
- Author Affiliations

A Department of Plant Physiology, Faculty of Biology, Sofia University ‘St Kliment Ohridski’, 8 Dragan Tsankov Boulevard, BG-1164 Sofia, Bulgaria.

B Department of Botany, Faculty of Biology, Sofia University ‘St Kliment Ohridski’, 8 Dragan Tsankov Boulevard, BG-1164 Sofia, Bulgaria.

C Department of Zoology and Anthropology, Faculty of Biology, Sofia University ‘St Kliment Ohridski’, 8 Dragan Tsankov Boulevard, BG-1164 Sofia, Bulgaria.

D Corresponding author. Email: zhiponova@biofac.uni-sofia.bg

Australian Journal of Botany 68(5) 352-362 https://doi.org/10.1071/BT19124
Submitted: 18 July 2019  Accepted: 19 August 2020   Published: 5 October 2020

Abstract

The genus Teucrium includes perennial herbs or shrubs widespread all around the world. The wall germander (Teucrium chamaedrys L.) is widely used in traditional and modern medicine for various health disorders and recent research revealed that serpentine populations of this herb have increased antioxidant and respective medical potential compared with calcareous population. The present study aims to elucidate further the role of phenolic compounds for T. chamaedrys growth on serpentine soil. Methanol extracts from two serpentine and two non-serpentine (calcareous and siliceous) Bulgarian populations were obtained and analysed for total quantity of phenolics and flavonoids, and antioxidant activity. The serpentine soils acted as an elicitor of the antioxidant response in T. chamaedrys plants and the increased phenolics level correlated with enhanced antioxidant activity. The calcareous population had lower values but still higher than the siliceous population which had the lowest antioxidant values, although the flavonoid quantity that was equal to the serpentine populations. A gas chromatography-mass spectrometry (GC-MS) assay for identifying phenolic acids pointed to caffeic acid as a dominant compound, with additional cinnamic and benzoic acid derivatives with putative roles as antioxidants, in cell wall lignification for heavy metals chelation, and for interspecies interactions.

Keywords: antioxidant activity, caffeic acid, GC-MS, Lamiaceae, phenolic acids.


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