Influence of extraction methods on the composition of essential oils of Achillea millefolium L. from Lithuania

In this study, flowering aerial parts of Achillea millefolium were used as a matrix for supercritical CO2 extraction (SFE) of volatile oil. 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 (HD). The composition of the essential oil obtained by hydrodistillation and SFE methods is widely different. Indeed, the SFE volatile oil had a pale yellow color whereas the HD oil had a blue color due to the presence of chamazulene (48.0% vs. 4.3%). Other important constituents of HD oil were (E)- caryophyllene (19.5 %) and γ-muurolene (13.1%). The CO2 supercritical extract was dominated by (E)-caryophyllene (26.0%), γ-muurolene (22.0%), and caryophyllene oxide (8.1%)

Chemical Composition and in Vitro Evaluation of the Antioxidant and Antimicrobial Activities of Eucalyptus gillii Essential Oil and Extracts

In this study, essential oil and various extracts (hexane, petroleum ether, acetone, ethanol, methanol and water) of Eucalyptus gilii were screened for their chemical composition, antimicrobial and antioxidant activities. The essential oil chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID), respectively. Thirty four compounds were identified, corresponding to 99.5% of the total essential oil. Tannins [104.9-251.3 g catechin equivalent (CE)/Kg dry mass], flavonoids [3.3-34.3 g quercetin equivalent (QE)/Kg dry mass], phenolics [4.7-216.6 g gallic acid equivalent (GAE)/Kg dry mass] and anthocyannins [1.2-45.3 mg cyanidin-3-glucoside equivalent (C3GE)/Kg dry mass] of various extracts were investigated. Free radical scavenging capacity of all samples was determinedt. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, the IC50 of essential oil was 163.5 ± 10.7 mg/L and in the 2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonate (ABTS) assay, it was 94.7 ± 7.1 mg/L. Among the various extracts, the water extract showed the best result (IC50 = 11.4 ± 0.6 mg/L) in the DPPH assay which was comparable to vitamin C (IC50 = 4.4 ± 0.2 mg/L). The antimicrobial activities were evaluated against different bacterial and fungal strains. Gram positive bacteria were found to be more sensitive to the essential oil and extracts than Gram negative ones. Anthocyanins seem to have a major effect on the growth of Bacillus subtilis (R2 = 0.79). A significant antifungal activity was observed against the yeast and fungi. Correlations between chemical composition and antioxidant activities were studied and R2 values were about 0.96 for the effect of phenolics on the DPPH assay

The essential oil of Thymbra capitata and its application as a biocide on stone and derived surfaces

Many chemicals used nowadays for the preservation of cultural heritage pose a risk to both human health and the environment. Thus, it is desirable to find new and eco-friendly biocides that can replace the synthetic ones. In this regard, plant essential oils represent effective alternatives to synthetic substances for the preservation of historical monuments. Thymbra capitata (syn. Thymus capitatus) is a medicinal and aromatic plant growing in the Mediterranean area and endowed with important pharmacological properties related to its essential oil. Among them, the antimicrobial ones make the T. capitata essential oil an ideal candidate for industrial applications; for instance, as biocide for the inhibition and elimination of biological patinas of cyanobacteria and green algae on historical monuments. In the present work, we studied the chemical composition of the essential oil from T. capitata growing in Malta by gas chromatography-mass spectrometry (GC/MS). The major volatile component is the phenolic monoterpene carvacrol (73.2%), which is capable of damaging the cytoplasmic membrane and to interfere both in the growth curve and in the invasive capacity, though the contribution of minor components γ-terpinene and p-cymene cannot be disregarded. For the oil application on the stone surface, Pickering emulsions systems were prepared with an essential oil/water 1:3 mass ratio stabilized with kaolinite at 4 mass% in the presence of Laponite®; this allowed to limit the fast volatility of the oil and guaranteed a better application and an easier removal from the artefacts attacked by biodeteriogens both indoor and outdoor. This formulation caused the elimination of biodeteriogens from treated surfaces without residuals or films on artworks surface, and the effect was retained up to four months

Oregano essential oils: Antimicrobial activity and its application to films based on cornstarch and glycerol

This trend has led to research on the development of new biodegradable packaging materials from natural polymers also suggests that several materials may be incorporated into edible films and have influence on the mechanical, protective and sensory properties. The objective of this work was to characterize oregano essential oils and incorporated edible films made with cornstarch and glycerol. The oregano essential oil obtain the raw material used was the variety Italian Oregano or Origanum majorana using a Clevenger-type apparatus. The study included the refractive index, chemical composition, color at day 0 and day 10 and antimicrobial activity of Salmonella Enteritidis and Escherichia Coli O157:H7. The films were prepared according to the method of casting, cornstarch, glycerol (plasticizer) and water. To assess the effect of the composition on the physical properties of films, the experiment was arranged in a 22 factorial design, with one central point. It analyzed the transfer of water vapor (Method ASTM E96-92) and color. The film which showed the best characteristics was selected; subsequently oregano essential oil was added. The refractive index of the oregano essential oils obtained from the various extractions varied between 1.4875 and 1.4981. There was a significant difference (P<0.05) between the parameters a* and b* between day 0 and day 10. According to gas chromatography analysis, 52 compounds were identified in oregano essential oil, thymol (31.96%) and carvacrol (0.66%) phenols. The test antimicrobial activity, showed that Salmonella Enteritidis and Escherichia Coli O157:H7 were extremely sensitive to pure essential oil. The films obtained were transparent, presented homogeneous and compact surfaces. The values of permeability to water vapor were between 1.93 x 10-12 and 9.85 x 10-12 (g/m.s.Pa). The Analysis of Variance (ANOVA) indicated a significant differences between the different formulation (P<0.05). The incorporation of oregano essential oil at the formulations influenced the permeability presenting more or less resistant to the passage of water vapor. About the color, incorporating essential oil did not affect the appearance and did not show strong antibacterial activity at the concentration at which it was decided to work.Fil: Córsico, Francisco Armando. Universidad Nacional de Entre Ríos. Facultad de Bromatología; ArgentinaFil: Larrosa, Virginia Judit. Universidad Nacional de Entre Ríos. Facultad de Bromatología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López Noviello, Luciano Hernán. Universidad Nacional de Entre Ríos. Facultad de Bromatología; ArgentinaFil: Altamirano, Alfonsina. Universidad Nacional de Entre Ríos. Facultad de Bromatología; ArgentinaFil: Naef, Antonella. Universidad Nacional de Entre Ríos. Facultad de Bromatología; ArgentinaFil: Alfaro, Cristina. Universidad Nacional de Entre Ríos. Facultad de Bromatología; ArgentinaFil: Garzón, Claudia Guadalupe. Universidad Nacional de Entre Ríos. Facultad de Bromatología; ArgentinaFil: Lound, Liliana Haydee. Universidad Nacional de Entre Ríos. Facultad de Bromatología; Argentin

Seasonal Variation of Essential Oil Yield and Composition of Sage (Salvia officinalis L.) Grown in Castilla - La Mancha (Central Spain)

Links between phenology, yield and composition of the essential oil of common sage, Salvia officinalis L., grown in Guadalajara (Central Spain) were determined in the different phases of the biological cycle during one year. Data showed an average yield about 1.0%. The analysis of the oil components was carried out by GC-FID and GC/MS. The main oil constituent was alpha thujone (40.1 - 46.5%). Other identified compounds are beta pinene (2.6 - 4.5%), cineole (3.5 - 8.7%), beta thujone (4.1 - 5.6%), camphor (4.1 - 8.0%), borneol (1.3 - 3.7%), alpha humulene (3.8 - 7.3%), viridiflorol (3.4-12.6%) and manool (0.1-4.5%). The highest yield of oil was obtained in the period of full flowering and the highest concentration of alpha thujone in the period of initial flowering

Chemical Composition and Antioxidant Effect of Free Volatile Aglycones from Nutmeg (Myristica fragrans Houtt.) Compared to Its Essential Oil

The paper reports on the isolation of glycosidically bound volatiles from nutmeg, identification of free aglycones, and determination of the antioxidative power of free aglycones in comparison with nutmeg essential oil. Comparison of the chemical composition of free volatiles with the chemical composition of free volatile compounds found in the essential oil reveals only two common compounds (eugenol, terpinen-4-ol). To measure the antioxidative activities of the essential oil and enzymatically released aglycones from nutmeg, two different assays were performed: the 2,2\u27-diphenyl-1-picrylhydrazyl radical scavenging method (DPPH) and the ferric reducing / antioxidant power assay (FRAP). Both methods showed that the aglycone fraction possesses stronger antioxidant properties than free volatiles from the oil

Comparitive Study on Essential Oil in Natural and In vitro Regenerated Plants of Vetiveria zizanioides (Linn.) Nash

In vitro studies with rhizome explants of Vetiveria zizanioides obtained through organogenetic pathway was focused on the difference in essential oil content with that of control plants. There was variation exhibited by In vitro regenerated plants in their morphological growth and were referred as “morphotypes”. Two types of morphotypes were identified as long and short based on differences in their height. Essential oil was extracted and analyzed by Gas chromatography. The two morphotypes showed varied essential oil content of 2.1% (long), 1.9% (short) with the control showing 1.8% and also the plants showed marked differences in percentage composition of essential oil with respect to important compounds like khusimol, valencene, vetiverol, vetivone, vetivenene, vetiselinol and nootketone. Further studies on the screening and selection of the chemotypes for high producing essential oil content and composition are under progress

Hypericum sp.: essential oil composition and biological activities

Phytochemical composition of Hypericum genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization as well as biological activities of H. perforatum crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett in Nat Prod Commun 5(9):1493–1506, 2010; Bertoli et al. in Global Sci Books 5:29–47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus.Fundação para a Ciência e a Tecnologia (FCT) - project PTDC/AGR AAM/70418/2006, SFRH/BD/ 13283/2003

Cytotoxic and Antimicrobial Constituents from the Essential Oil of Lippia alba (Verbenaceae).

Backgroud:Lippia alba (Verbenaceae) is a plant widely used in folk medicine to treat various diseases. The present work deals with the chemical composition of the crude essential oil extracted from leaves of L. alba and evaluation of its antimicrobial and cytotoxic activities. Methods: Leaves of L. alba were extracted by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) as well as by nuclear magnetic resonance (NMR) spectroscopy. Cytotoxic and antimicrobial activities of crude essential oil were evaluated in vitro using MTT and broth microdilution assays, respectively. Results: Chemical analysis afforded the identification of 39 substances corresponding to 99.45% of the total oil composition. Concerning the main compounds, monoterpenes nerol/geraniol and citral correspond to approximately 50% of crude oil. The cytotoxic activity of obtained essential oil against several tumor cell lines showed IC50 values ranging from 45 to 64 µg/mL for B16F10Nex2 (murine melanoma) and A549 (human lung adenocarcinoma). In the antimicrobial assay, was observed that all tested yeast strains, except C. albicans, were sensitive to crude essential oil. MIC values were two to four-folds lower than those determined to bacterial strains. Conclusion: Analysis of chemical composition of essential oils from leaves of L. alba suggested a new chemotype nerol/geraniol and citral. Based in biological evidences, a possible application for studied oil as an antifungal in medicine, as well as in agriculture, is described