Influence of Extraction Solvent on the Phenolic Profile and Bioactivity of Two Achillea Species

The phenolic composition, as well as the antioxidant and antimicrobial activities of two poorly investigated Achillea species, Achillea lingulata Waldst. and the endemic Achillea abrotanoides Vis., were studied. To obtain a more detailed phytochemical profile, four solvents with different polarities were used for the preparation of the plant extracts whose phenolic composition was analyzed using UHPLC-MS/MS (ultra-high performance liquid chromatography-tandem mass spectrometry). The results indicate that both of the investigated Achillea species are very rich in both phenolic acids and flavonoids, but that their profiles differ significantly. Chloroform extracts from both species had the highest yields and were the most chemically versatile. The majority of the examined extracts showed antimicrobial activity, while ethanolic extracts from both species were potent against all tested microorganisms. Furthermore, the antioxidant activity of the extracts was evaluated. It was found that the ethanolic extracts possessed the strongest antioxidant activities, although these extracts did not contain the highest amounts of detected phenolic compounds. In addition, several representatives of phenolic compounds were also assayed for these biological activities. Results suggest that ethanol is a sufficient solvent for the isolation of biologically active compounds from both Achillea species. Moreover, it was shown that the flavonoids naringenin and morin are mainly responsible for these antimicrobial activities, while caffeic, salicylic, chlorogenic, p-coumaric, p-hydroxybenzoic, and rosmarinic acid are responsible for the antioxidant activities of the Achillea extracts.

Chemical Characterization and Antibacterial Activity of Essential Oil of Medicinal Plants from Eastern Serbia

The objective of this study was to evaluate wild growing Satureja kitaibelii, Thymus serpyllum, Origanum vulgare, Achillea millefolium and Achillea clypeolata with respect to their essential oil (EO) content, composition and antimicrobial activity. The five species were collected at Mt. Rtanj and the village of Sesalac, Eastern Serbia. The main EO constituents of Lamiaceae plants were p-cymene (24.4%), geraniol (63.4%) and germacrene D (21.5%) in Satureja kitaibelii, Thymus serpyllum and Origanum vulgare ssp. vulgare, respectively. A. millefolium EO had multiple constituents with major ones being camphor (9.8%), caryophyllene oxide (6.5%), terpinen-4-ol (6.3%) and 1,8-cineole (5.6%), while the main EO constituents of A. clypeolata were 1,8-cineole (45.1%) and camphor (18.2%). Antimicrobial testing of the EO showed that Staphylococcus aureus (Gram-positive) was more sensitive to all of the tested EOs than Escherichia coli (Gram-negative). S. kitaibelii EO showed the highest antimicrobial activity against both tested bacterial strains. This is the first study to characterize the EO composition and antimicrobial activity of these five medicinal species from Eastern Serbia in comparison with comprehensive literature data. The results can be utilized by the perfumery, cosmetics, food and pharmaceutical industries, but also for healing purposes in self-medication.

Chemical Composition and Antibacterial Activity of the Bulgarian Endemic Species Achillea thracica from its Natural Habitat, and in vitro Propagated and ex vitro Established Plants

The present study reports the chemical composition of headspace volatiles (HS) and acetone extracts of the endemic Bulgarian species Achillea thracica Velen. from its natural habitat (N), in vitro propagated (IN) and ex vitro established (EX) plants. Additionally, acetone extracts were tested by a disk diffusion method for antibacterial activity. Irregular monoterpenes were the most abundant HS volatile constituents, while O,O-dimethyl quercetin was the most abundant flavonoid in the acetone extracts. The secondary metabolites of A. thracica grown in its natural habitat (N), propagated in vitro (IN) and ex vitro established (EX) showed that the qualitative composition is mutually similar, but there are differences in the quantitative composition. Considering antibacterial activity, IN and EX samples showed moderate activity against Pseudomonas aeruginosa and Escherichia coli.

Essential Oil Chemical Composition and Headspace Volatiles Profile of Achillea coarctata from Serbia

This study reports the essential oil composition and headspace volatiles profile of Achillea coarctata Poir. from Serbia. The inflorescences, stems and leaves, and the aerial parts of A. coarctata were analyzed separately. Germacrene D, α-terpineol and 1,8-cineole were the main constituents of the aerial parts essential oil; 1,8-cineole, cis-cadin-4-en-7-ol and α-terpineol were the most dominant compounds in the inflorescence essential oil, while the most abundant components in the stem and leaf oil were germacrene D, cis-cadin-4-en-7-ol and ledol. The percentages of monoterpenoids and sesquiterpenoids in the aerial parts were the same, while there were differences in distribution of these compound classes in inflorescence and stem and leaf essential oils. The major components of the headspace volatiles were the same for aerial parts, inflorescence and stem and leaves: 1,8-cineole, β-pinene and α-pinene.

Chemical Composition and Biological Activity of the Volatile Extracts of Achillea millefolium

In this study, flowering aerial parts of wild Achillea millefolium growing on the Mediterranean coast (Sardinia Island, Italy) and on the Atlantic coast (Portugal- Serra de Montemuro) were used as a matrix for supercritical extraction of volatile oil with CO2 (SFE). The collected extracts were analyzed by GC-FID and GC-MS methods and their composition were compared with that of the essential oil isolated by hydrodistillation. A strong chemical variability in essential oils depending on the origin of the samples was observed. The results showed the presence of two type oils. The Italian volatile extracts (SFE and essential oil) are predominantly composed by α-asarone (25.6-33.3%, in the SFE extract and in the HD oil, respectively), β-bisabolene (27.3-16.6%) and α-pinene (10.0-17.0%); whereas the main components of the Portuguese extracts are trans-thujone (31.4-29.0%), trans-crhysanthenyl acetate (19.8-15.8%) and β-pinene (1.2-11.1%).

The minimal inhibitory concentration (MIC) and the minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the oils against Candida albicans, C. tropicalis, C. krusei, C. guillermondii, C. parapsilosis, Cryptococcus neoformans, Trichophyton rubrum, T. mentagrophytes, T. mentagrophytes var. interdigitale, T. verrucosum, Microsporum canis, M. gypseum, Epidermophyton floccosum, Aspergillus niger, A. fumigatus and A. flavus. The oils showed the highest activity against dermatophyte strains, with MIC values ranging from 0.32-1.25 μL mL−1.

Essential Oil Composition of Five Collections of Achillea Biebersteinii from Central Turkey and their Antifungal and Insecticidal Activity

The composition of the essential oils hydrodistilled from the aerial parts of five Achillea biebersteinii Afan samples, collected in central Turkey from Konya, Isparta and Ankara, were analyzed both by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Eighty-four components were identified, representing 87 to 99% of the total oil composition. The identified major components were 1,8-cineole (9-37%), camphor (16-30%) and p-cymene (1-27%). Two samples differed in piperitone (11%) and ascaridol (4%) content. The five A. biebersteinii essential oils were subsequently evaluated for their antifungal activity against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides using the direct overlay bioautography assay. The essential oils showed no antifungal activity at 80 and 160 μg/spot. In addition, A. biebersteinii oils and their major compounds were subsequently investigated against Aedes aegypti first instar larvae in a high throughput bioassay. Among the oils, only one sample from Ankara showed a notable larvacidal effect on Ae. aegypti larvae. The major compounds, 1,8-cineole, camphor and p-cymene, exhibited low mosquito larval activity, and thus the minor compounds are probably responsible for the observed activity against Ae. aegypti larvae. The oils showed weak activity against adult Ae. aegypti.

Volatile Profiles of Artemisia alba from Contrasting Serpentine and Calcareous Habitats

GC and GC-MS analyses of the essential oils of two populations of Artemisia alba Turra, wild-growing on calcareous and serpentine substrates, enabled the identification of 227 different components. Volatile profiles of the two samples differed significantly and only 48 components were in common to both oils. Major constituents of the oils were as follows: germacrene D (38.3%) in the serpentinophyte A. alba (sometimes regarded as A. alba ssp. saxatilis or A. saxatilis) oil and spathulenol (11.8%), artemisia ketone (10.1%), camphor (7.5%) and 1,8-cineole (7.4%) in A. alba (from calcareous habitat) oil. The noted differences were observable on the class level as well: with 73% the sesquiterpenoids (48.2% hydrocarbons, 24.5% oxygen or sulfur containing) were the most abundant compound class in A. saxatilis oil, while the other oil was dominated by monoterpenoids, comprising ca. 60% of the oil (2.1% hydrocarbons and 54.7% oxygenated). Additionally, the serpentinophyte yielded ca. four times less essential oil. These results pointed out to the fact that the type of substrate (soil) could have an important influence on the biosynthesis of A. alba volatiles (genetically predetermined or environmental), especially in the case of populations grown on serpentine rock, characterized by a deficiency of water and indispensable mineral elements.

Essential Oil Composition of Achillea clusiana from Bulgaria

The essential oil compositon of Achillea clusiana Tausch from Bulgaria has been studied by GC and GC/MS. Fifty-four components were registered, representing 92.5% of the oil. The oil was characterized by the presence of oxygenated mono- and sesquiterpenoids. The main components were β-thujone (17.2%), 1,8-cineole (11.2%), camphor (11.1%) and α- thujone (7.8%). Farnesol (3.1%), nerolidol (2.7%) and oxygenated nerolidol derivatives (cabreuva oxides A-D, isohumbertiols A-D, bejarol and 7-hydroxy-6,7-dihydro-5,6E-dehydronerolidol) were the main sesquiterpenoids in the oil.