Search results for "ESSENTIAL OIL"
showing 10 items of 443 documents
Composition of essential oil of lemon thyme (Thymus × citriodorus) at different hydrodistillation times.
2018
Distillation time can both to optimise the production and to engineer the composition of essential oil in essential oil bearing plants. Purpose of this study was to evaluate the effect of duration of hydrodistillation on composition of essential oil of Thymus × citriodorus, the natural source of commercially important geraniol and citral, a component with valuable biological properties. Essential oils were isolated by hydrodistillation at different distillation times and analysed by GC/MS analytical methods. Increase in percentage of essential oil during all hydrodistillation time gradient was uneven. Elongation of hydrodistillation time decreased percentages of monoterpenes but increased p…
Comparative chemical study and antimicrobial activity of essential oils of three Artemisia species from Egypt and Saudi Arabia
2019
Effect of bioclimatic area on the composition and bioactivity of Tunisian Rosmarinus officinalis essential oils
2014
The chemical composition of eight Tunisian Rosmarinus officinalis L. populations (A-H) from different bioclimatic areas has been examined by gas chromatography (GC) and GC-mass spectrometry. The essential oils are characterised by high amounts of oxygenated monoterpenes (58.2-71.7%) followed by monoterpene hydrocabons (15.1-26.7%). 1,8-Cineole, camphor, α-pinene and borneol are the main representative components. The antioxidant activity was investigated by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing ability power assay and β-carotene bleaching test. Samples showed antiradical activity by inhibiting DPPH radical with IC50 values ranging from 375.3 to 592.8 μg mL(- 1) for s…
Volatile components from aerial parts of Centaurea gracilenta and C. ovina ssp. besserana growing wild in Bulgaria
2011
The essential oils of Centaurea gracilenta Velen. (CG) and C. ovina Pall. ex Willd. ssp. besserana (DC.) Dostál (COB) growing wild in Bulgaria, were studied by GC and GC-MS. Forty-five compounds for CG, representing the 90.1% of the oil, and 68 compounds for COB, representing the 91.9% of the oil, were identified. The oils were rich in sesquiterpenoids (33.4% for CG and 27.3% for COB), hydrocarbons (28.3% for CG and 10.7% for COB) and carbonylic compounds (12.7% for CG and 13.1% for COB). Fatty acids were abundant only for COB (31.3%). beta-Eudesmol (12.8%), nonacosane (11.8%) and p-vinyl guiacol (7.5%) were recognized as the main constituents for CG, while hexadecanoic acid (21.4%), spathu…
Chemical composition of the essential oil of Phagnalon saxatile (L.) Cass. (Asteraceae) growing wild in Southern Italy
2005
Abstract The essential oil from aerial parts of Phagnalon saxatile (L.) Cass. (Asteraceae) was obtained by hydrodistillation. The oil content was 0.15% (v/w), on a dry weight basis. The oil composition was analyzed by GC and GC/MS. Altogether 66 compounds were identified accounting for 93.2% of the oil. Sesquiterpenes represent the 23.9% of the oil. In the oil were also present fatty acids (21.8%) and waxes (19.3%). The oil shows no antibacterial activity.
Development and characterization of essential oil component-based polymer films: a potential approach to reduce bacterial biofilm
2013
The development of new polymeric materials aimed to control the bacterial biofilm appears to be an important practical approach. The goal of the present study was to prepare and characterize poly(ethylene-co-vinyl acetate) copolymer (EVA) films containing citronellol, eugenol, and linalool and evaluate their efficiency on growth and biofilm formation of Listeria monocytogenes, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa in monospecies and dual species. The results showed that the addition of oil components influenced the elastic modulus (15 % decrease), the tensile stress (30 % decrease), the elongation at break (10 % increase), and the co…
Extraction of essential oil from Aloysia citriodora Palau leaves using continuous and pulsed ultrasound: Kinetics, antioxidant activity and antimicro…
2018
International audience; The impact of continuous and pulsed ultrasound pre-treatments (15, 30 and 45 min) followed by conventional hydrodistillation on the characteristics of extracted essential oils (EOs) from dried leaves of Aloysia citriodora Palau was evaluated for the first time. Chemical composition of EOs, antibacterial and antioxidant activities, as well as the contents in heavy metals (iron, copper, lead, arsenic, and cadmium) were determined. Pretreating the leaves with ultrasound (continuous and pulsed), before hydrodistillation, resulted in shorter extraction time (93.81–121.16 min) and higher extraction yields (2.8 (v/w) %) (p < 0.05), compared to the non-sonicated leaves (extr…
Oli essenziali e loro applicazione in agricoltura: un’analisi della letteratura attraverso VOSviewer
2023
The new guidelines of the European Commission intend to reduce the use of pesticides by 50%. A valid sustainable alternative to chemicals products in agriculture seems to be essential oils (EOs). The role of OEs is to cope external stressors for protecting plants themselves from pests and/or insects, bacteria, fungi and nematodes. The purpose of the work is to investigate which EOs have been evaluated in agriculture in the last 100 years, specially focusing on main target activities (antibacterial, insecticidal, fungicidal, acaricidal, antiviral, nematocidal). The examination has been done with VOSviewer software, which through the cluster analysis of scientific literature available on Scop…
Essential oils as multi-target compounds for novel food safety strategies
This research work has been developed in the context of the potencial applications of essential oils as multi-target compounds for novel food safety strategies, such as active packaging technologies. Essential oils are aromatic oils derived from plants and usually extracted by hydrodistillation when intended to be used in food. There is an increasing interest in the antimicrobial properties of essential oils due to the possibility of using them to replace ‘synthetic’ preservatives in food or, in general, to reduce viable numbers of pathogens along the food chain.
Composition of the essential oil from flowerheads of Chrysanthemum coronarium L. (Asteraceae) wild growing in Southern Italy
2004
The essential oils from the aerial parts of Chrysanthemum coronarium L. (Asteraceae) growing wild in two different localities of Southern Italy, Lascari (L) and Palinuro (P), were obtained by hydrodistillation in a 0.13–0.16% yield. The oils were analysed by GC and GC–MS; 68 constituents, amounting to 89.0% of the oil (L), and 43 constituents, amounting to 91.6% of the oil (P), were identified. The trans‐spiroketal–enol ether 2‐(2,4‐hexadiynylidene)‐1,6‐dioxaspiro[4,4]non‐3‐ene (trans‐tonghaosu) with chrysanthenyl and lyratyl esters and camphor were the main components of the oils.