Volatile Composition, Antimicrobial Activity, and In Vitro Innate Immunomodulatory Activity of Echinacea purpurea (L.) Moench Essential Oils

Abstract

Echinacea purpurea (L.) Moench is a medicinal plant commonly used for the treatment of upper respiratory tract infections, the common cold, sore throat, migraine, colic, stomach cramps, and toothaches and the promotion of wound healing. Based on the known pharmacological properties of essential oils (EOs), we hypothesized that E. purpurea EOs may contribute to these medicinal properties. In this work, EOs from the flowers of E. purpurea were steam-distilled and analyzed by gas chromatography–mass spectrometry (GC–MS), GC with flame-ionization detection (GC–FID), and chiral GC–MS. The EOs were also evaluated for in vitro antimicrobial and innate immunomodulatory activity. About 87 compounds were identified in five samples of the steam-distilled E. purpurea EO. The major components of the E. purpurea EO were germacrene D (42.0 ± 4.61%), α-phellandrene (10.09 ± 1.59%), β-caryophyllene (5.75 ± 1.72%), γ-curcumene (5.03 ± 1.96%), α-pinene (4.44 ± 1.78%), δ-cadinene (3.31 ± 0.61%), and β-pinene (2.43 ± 0.98%). Eleven chiral compounds were identified in the E. purpurea EO, including α-pinene, sabinene, β-pinene, α-phellandrene, limonene, β-phellandrene, α-copaene, β-elemene, β-caryophyllene, germacrene D, and δ-cadinene. Analysis of E. purpurea EO antimicrobial activity showed that they inhibited the growth of several bacterial species, although the EO did not seem to be effective for Staphylococcus aureus. The E. purpurea EO and its major components induced intracellular calcium mobilization in human neutrophils. Additionally, pretreatment of human neutrophils with the E. purpurea EO or (+)-δ-cadinene suppressed agonist-induced neutrophil calcium mobilization and chemotaxis. Moreover, pharmacophore mapping studies predicted two potential MAPK targets for (+)-δ-cadinene. Our results are consistent with previous reports on the innate immunomodulatory activities of β-caryophyllene, α-phellandrene, and germacrene D. Thus, this study identified δ-cadinene as a novel neutrophil agonist and suggests that δ-cadinene may contribute to the reported immunomodulatory activity of E. purpurea.

Chemical Composition of the Essential Oils of the Iberian Peninsula Endemic Species Eryngium dilatatum Lam.

“…In the present paper, the biological properties of the essential oils from the various fractions of this species were not evaluated due to the limited amount of oil available. However, germacrene D, the major component of these oils is a hydrocarbon sesquiterpene for which a number of bioactivities have previously been reported [97][98][99][100]. It would be interesting to study the phenology of this compound in this species to evaluate the usefulness of E. dilatatum oils for attracting/repelling insects or for allopathic and antimicrobial activities.…”

Echinacea purpurea: An overview of mechanism, efficacy, and safety in pediatric upper respiratory infections and otitis media

“…E. purpurea contains a complex mixture of bioactive compounds, including alkamides, caffeic acid derivatives, polysaccharides, flavonoids, and essential oils (Daley, 2019;Dosoky et al, 2023;. The main chemical composition of E. purpurea, as reported by previous studies (Burlou-Nagy et al, 2022), is outlined in Table 1.…”

“…Anti-inflammatory, antiallergic, antioxidant, antiviral (Burlou-Nagy et al, 2023;Kurkin et al, 2011;Lee et al, 2010;Maleki et al, 2019;Manayi et al, 2015) Alkaloids: Tussilagin, isotussilagin Root, aerial part Gastrointestinal-protective, anti-tumoral, hepatoprotective (Aarland et al, 2017;Burlou-Nagy et al, 2023;Manayi et al, 2015;Miller & Yu, 2004;Petrova et al, 2023;Xu et al, 2021) Volatile constituents: germacrene D, α-phellandrene, βcaryophyllene, γ-curcumene, αpinene, δ-cadinene, α-cadinol Root, leaves, flower Antimicrobial, analgesic, anti-inflammatory, immunomodulatory (Dosoky et al, 2023;Nyalambisa et al, 2017) 4. Potential mechanisms of action of E. purpurea on treating URI and OM…”

Analytical Assessment of the Antioxidant Properties of the Coneflower (Echinacea purpurea L. Moench) Grown with Various Mulch Materials

“…Echinacea purpurea L. (Moench) is a native and ornamental plant in the Atlantic geographical drainage area of the United States of America and Canada, but not including Mexico. The cultivation of this plant is also popular in Europe [ 1 , 2 ]. Based on some data in the literature, it is reported that E. purpurea is the last one in a list of the ten most frequently cultivated herbs in Poland [ 3 , 4 ].…”