Labdane-type diterpenoids from Juniperus communis needles

Abstract

Herein we report the extraction of labdane-type diterpenoids from the needles of the common juniper (Juniperus communis ssp. communis var. communis L.), and identification of them as the major class of compounds in this species. Furthermore, and to the best of our knowledge we provide the first-ever report some of these compounds (nor-16-imbricatolic, nor-16-acetylimbricatolic and acetylimbricatolic acids) as natural compounds. Imbricataloic and imbricatolic acids were the most abundant compounds, accounting for 65% of the total extract. We also found long-chain secondary alcohols (n-alkan-10-ols) and secondary/secondary alkanediols (4,10-, 5,10-, 6,10-, 7,10-), which we report here for the first time ever in the genus Juniperus. In total, we identified 127 compounds: of these, 48 (nonacosan-10-ols, -tocopherols and lignans) are described here for the first time in Juniperus and 54 (including alkanols, phytol, sterols and flavonoids), for the first time in common juniper. Highlights 127 phytochemical constituents of the needles of Juniperus communis were investigated with imbricatolic and imbricatalic acid as the most abundants  3 Labdane-type diterpenoids are new natural products  17 compounds have no precedent in Juniperus genus and 32 are described for the first time from Juniperus communis Keywords: Juniperus communis; Common juniper; Diterpenoids; Labdane-type; Alkanediols; Imbricatolic acid; Gas chromatography-Mass spectrometry (GC/MS); Trimethylsilyl (TMS) ether derivatives. IntroductionThe genus Juniperus (Cupressaceae) comprises 68 species and 36 varieties growing principally in the northern hemisphere . The chemical composition of the genus Juniperus has been extensively reviewed by Seca & Silva (2006). Table 1 summarizes the phytochemical characteristics of the principal compounds from the genus Juniperus, excluding terpenes, secondary alcohols and secondary diols, which we discuss separately in a latter section.The species Juniperus communis L. comprises four subspecies, including the common juniper (J. communis ssp. communis), a coniferous evergreen shrub that has a broad geographic range throughout the holarctic region. In fact, it exhibits the largest range of any woody plant, spanning the cool, temperate, part of the Northern Hemisphere: from mountains in the southern arctic, to roughly 30ºN latitude in North America, Europe and Asia. It tolerates a variety of climatic and edaphic conditions. The surface layer of plant leaves typically contains many classes of compounds, including alkanes, primary alcohols, acids, aldehydes, terpenes and phenols. However, there are very few reports on the overall composition of common-juniper needles. Thus, in the study reported here, we sought to analyze the soluble fraction of common-juniper needles.We analyzed the total extract of common-juniper needles and identified each wax-class of compounds, discovering many acyclic and cyclic compounds from three major groups: terpenoids (e.g. sesquiterpenes and diterpenes); phenols (including phenolic acids,...

Chemical Fingerprinting of Conifer Needle Essential Oils and Solvent Extracts by Ultrahigh-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

“…Bornyl p -coumarate, which was reported as the major compound in the acid fraction of Pinus koraiensis needle lipophilic extract, was present at low abundance. Other labdanoids, which have been reported in other studies and were also detected in this work, include anticopalic acid, first isolated from the bark and sap wood of western white pine, and acetylisocupressic acid …”

“…A homologous series of monoglycerides were also identified in the extracts. These monoglycerides have been reported in common juniper …”

“…Basas-Jaumandreu et al reported it as the most abundant compound found in the extract of J. communis needles . Structures of these acids are presented in Figure .…”

“…Basas-Jaumandreu et al reported it as the most abundant compound found in the extract of J. communis needles. 49 Structures of these acids are presented in Figure 6. Bornyl p-coumarate, which was reported as the major compound in the acid fraction of Pinus koraiensis needle lipophilic extract, 31 was present at low abundance.…”

Adsorption of Basic Blue 41 using Juniperus excelsa: Isotherm, kinetics and thermodynamics studies

“…The chemical composition and the phytochemical characteristics of the principal compounds of Juniperus genus are summarized before. Juniperus genus has many biological effects which might be antifungal, antiviral, antimicrobial, anticancer, cytotoxic, antifungal and antioxidant [15,16]. There are few studies and data on chemical compositions of the related Juniperus species because of widespread using Juniperus species in many areas.…”