Chemo‐Geographic Variations in Wild Population of Asteriscus graveolens in Israel Based on Volatile Composition Analyses

Abstract

Asteriscus graveolens is an aromatic desert shrub which holds medicinal potential. This species belongs to the Asteraceae family and is endemic to the Mediterranean region. In the present study, wild plants were sampled from eleven locations throughout southern Israel and the volatile profiles from leaves and flowers were analyzed using GC/MS. Three methods for volatile sampling were tested for a representative population: solvent extraction (methyl tert-butyl ether), hydrodistillation of the essential oil and headspace solid-phase microextraction. In all methods, the majority of volatiles were characterized as oxygenated mono-and sesquiterpenes. Only solvent extraction was able to detect asteriscunolides that were previously reported as anticancer molecules. Hence, that method was chosen for further analyses. The leaves were dominated by three asteriscunolide isomers, cischrysanthenyl acetate and intermedeol. The flowers were dominated by bisabolone, 6-hydroxybisabol-2-en-1one, cis-chrysanthenyl acetate, epi-α-cadinol, and germacrene-D. k-Means clustering analysis of these data divided the population into four clusters that significantly differ in their volatile composition as was further demonstrated by MANOVA analysis. Geographically, A. graveolens populations growing in Israel were found to be chemically diverse with unique varieties in the Dead Sea basin and the Arava region. This work demonstrates that chemo-geographic variation of volatile composition exists within A. graveolens population growing in Israel, so future research evaluating the medicinal potential of that plant should take this into consideration.

Volatile Composition Variability of Arnica montana Wild Populations of Trentino‐Alto Adige, Italy, Determined by Headspace‐Solid Phase Microextraction

“…[22,23] Furthermore, the existing variability within A. montana has been investigated based on the flower head's chemical composition while focusing on these classes of compounds. [4,[24][25] While several studies on volatile composition as a source of differentiation within the same taxon have been carried out, [26][27][28] none have addressed Arnica montana. The current study aims were to determine the volatile composition of flower heads of Arnica montana using Headspace-Solid Phase Microextraction (HS-SPME) analysis and characterize the volatile profile of natural populations growing in the Italian Trentino-Alto Adige region.…”