Phenolic Compounds as Unambiguous Chemical Markers for the Identification of Keystone Plant Species in the Bale Mountains, Ethiopia

Abstract

: Despite the fact that the vegetation pattern and history of the Bale Mountains in Ethiopia were reconstructed using pollen, little is known about the former extent of Erica species. The main objective of the present study is to identify unambiguous chemical proxies from plant-derived phenolic compounds to characterize Erica and other keystone species. Mild alkaline CuO oxidation has been used to extract sixteen phenolic compounds. After removal of undesired impurities, individual phenols were separated by gas chromatography and were detected by mass spectrometry. While conventional phenol ratios such as syringyl vs. vanillyl and cinnamyl vs. vanillyl and hierarchical cluster analysis of phenols failed for unambiguous Erica identification, the relative abundance of coumaryl phenols (>0.20) and benzoic acids (0.05—0.12) can be used as a proxy to distinguish Erica from other plant species. Moreover, a Random Forest decision tree based on syringyl phenols, benzoic acids (>0.06), coumaryl phenols (<0.21), hydroxybenzoic acids, and vanillyl phenols (>0.3) could be established for unambiguous Erica identification. In conclusion, serious caution should be given before interpreting this calibration study in paleovegetation reconstruction in respect of degradation and underground inputs of soil organic matter.

Optimization of Germination Inhibitors Elimination from Sugar Beet (Beta vulgaris L.) Seeds of Different Maturity Classes

“…Among various candidates for this inhibitory reaction, phenolic compounds have received the most attention [3,16,17]. Phenols are the major class of secondary compounds in terrestrial vascular plants [22]. Phenolic compounds or their derivatives are known as seed germination inhibitors [23].…”

“…Some phenolic compounds are intermediates in lignin biosynthesis, which happens in the perianth lignification process [3]. These compounds can be investigated by different methods, including HPLC, LC-MS, ultraviolet absorption [22,24]. Analyzing the UV-visible absorbance spectrum of beet seed steeping solutions is a reliable way to detect differences among different groups of seeds [17].…”

Effect of Altitude on Volatile Organic and Phenolic Compounds of Artemisia brevifolia Wall ex Dc. From the Western Himalayas

“…Most of these compounds (except for epicatechin, ferulic acid, picein, and taxifolin) were reported from various Artemisia species, namely A. armeniaca, A. incana, A. tournefortiana, A. haussknechtii, A. scoparia, A. annua, and A. absinthium (Ferreira et al, 2010;Lee et al, 2013;Kursat et al, 2015). Caffeic acid, catechin, chlorogenic acid, coumaric acid, ferulic acid, myricetin, picein, quercetin, and vanillic acid were also reported from some alpine plants such as Bistorta vivipara, Dryas octopetala, Salix reticulate, and Lobelia rhynchopetalum (Nybakken et al, 2008;Lemma et al, 2019). The calibration curve for our 15 standards was prepared using MeOH as a solvent to get a concentration of 1 mg/ml.…”

HPLC/DAD, Antibacterial and Antioxidant Activities of Plectranthus Species (Lamiaceae) Combined with the Chemometric Calculations

“…Phenolic compounds are extensively used in botanical chemosystematic studies. The chemotaxonomic values of phenolic biomolecules such as these has been recognized in the plant kingdom [21]. Apart from the chemotaxonomic significance, its biological activities stand out as well as the role of phenolic compounds as indicators of the presence of metals in the leaves of different botanical genera [22].…”