The Phytochemical and Genetic Survey of Common and Dwarf Juniper (Juniperus communisandJuniperus nana) Identifies Chemical Races and Close Taxonomic Identity of the Species

Abstract

Juniperus communis L. (= J. communis var. communis) and Juniperus nana Willd. (= J. communis var. SAXATILIS) are subspecies of juniper. J. communis grows widely in both hemispheres, primarily in lower elevations while J. nana is mainly observed in high mountains. Although they can be distinguished by morphological features, it is not known whether they are genetically and phytochemically distinct entities. We aimed to check whether it is possible to distinguish these two plants (i) by pharmaceutically important chemical traits and (ii) on the basis of intraspecifically highly polymorphic fragment of chloroplast DNA. We used GC with achiral as well as with enantioselective stationary phase columns to identify the main monoterpenes of the essential oil. Sequence analysis of the TRNL (UAA)- TRNF (GAA) intergenic spacer of the chloroplast genome was used as a genetic marker of taxonomic identity between these two subspecies. The chromatographic analysis showed the existence of three chemical races - the alpha-pinene type, the sabinene type and one with intermediate contents of these terpenes among both J. communis and J. nana. Surprisingly, sequence analysis of TRNL (UAA)- TRNF (GAA) revealed 100 % similarity between the common and the dwarf juniper. Thus, the monoterpene pattern is related to geographical origin, and not to the species identity. We suggest that the three chemical races identified in the present study should be considered as separate sources of pharmaceutical raw material. Our results demonstrate that the contents of alpha-pinene and sabinene may be applied as a quick diagnostic test for preliminary evaluation of plant material.

Genetic diversity of Lithuanian populations of Juniperus communis L. in relation to abiotic and biotic factors

“…Influence of external factors on genetic diversity of the junipers including geographical proximity (Oostermeijer & Knegt, 2004;Sobierajska et al, 2016), long-term evolution (Hantemirova et al, 2012;Filipowicz et al, 2006;Meloni et al, 2006;Boratyński et al, 2014) has been shown in previous studies. However, there are only few studies where habitat-related peculiarities are mentioned: association between ISSR-related data and habitat type of populations have been described for J. brevifolia populations from the Azorean archipelago (Silva et al, 2011) and J. communis from Wales and England (Van der Merwe et al, 2000).…”

“…Significant part of Juniperus surveys is devoted to relate DNA polymorphism and essential oils (Adams, 2011;Filipowicz et al, 2006). Influence of external factors on genetic diversity of the junipers including geographical proximity (Oostermeijer & Knegt, 2004;Sobierajska et al, 2016), long-term evolution (Hantemirova et al, 2012;Filipowicz et al, 2006;Meloni et al, 2006;Boratyński et al, 2014) has been shown in previous studies.…”

HS‐SPME/GC Analysis Reveals the Population Variability of Terpene Contents in Juniperus communis Needles

“…On the contrary, sabinene showed strong positive correlation with the following monoterpenes: athujene (r ¼ 1.0), g-terpinene (r ¼ 0.9), terpinolene (r ¼ 0.8), and terpinen-4-ol (r ¼ 0.7). The positive relation between sabinene and terpinen-4-ol was also described in [16] [21]. Moreover, Hiltunen and Laakso suggested that the association between contents of sabinene and a-thujene is a result of its biosynthetic route via the thujane-4-carbonium ion [16].…”

“…The cluster representing all individuals classified as sabinene chemotype was easily distinguishable, while intermediate chemotype samples were placed within the second big cluster, dominated by a-pinene. In a previous paper, we also reported that J. communis and J. nana can possess different monoterpenic patterns and thus can be divided into three chemotypes: a-pinene (sabinene < 10%, and 50% < a-pinene < 90%), intermediate (30% < a-pinene < 60%, and 10% < sabinene < 30%), and sabinene (10% < a-pinene < 40%, and 30% < sabinene < 50%) [21]. These patterns could have been observed in this study.…”

Chemical Variability of the Needle Oil of Juniperus communis ssp. alpina from Corsica

“…communis and J. communis ssp. alpina (named J. nana in the article) suggested that the monoterpene pattern (oil samples dominated by a-pinene, sabinene, or both compounds) is related to the geographical origin [15].…”