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Antibacterial properties and chemical characterization of the essential oils from summer savory extracted by microwave-assisted hydrodistillation
Rezvanpanah, Shila;Rezaei, Karamatollah;Golmakani, Mohammad-Taghi;Razavi, Seyyed Hadi;
Brazilian Journal of Microbiology , 2011, DOI: 10.1590/S1517-83822011000400031
Abstract: antibacterial properties and chemical characterization of the essential oils from summer savory (satureja hortensis) extracted by microwave-assisted hydrodistillation (mahd) were compared with those of the essential oils extracted using the traditional hydrodistillation (hd) method. while mahd at 660 w required half as much time as hd needed, similar antibacterial efficacies were found from the essential oils obtained by the two extraction methods on two food pathogens (staphylococcus aureus, a gram positive bacterium, and escherchia coli, a gram negative bacterium). also, as it was the case with the essential oils extracted by hd, that of mahd indicated greater influence on s. aureus than on e. coli. the compositions of the extracted essential oils were also studied using gc-ms analysis. the same components with negligible differences in their quantities were found in the extracted essential oils using the two methods outlined above. overall, to reduce the extraction time, mahd can be applied at higher microwave levels without any compromise in the antibacterial properties of the essential oils extracted.
Chemical Composition and Antibacterial Activity of Essential Oils from Different Parts of Leonurus japonicus Houtt.  [PDF]
Liang Xiong,Cheng Peng,Qin-Mei Zhou,Feng Wan,Xiao-Fang Xie,Li Guo,Xiao-Hong Li,Cheng-Jun He,Ou Dai
Molecules , 2013, DOI: 10.3390/molecules18010963
Abstract: The herb and fruits of Leonurus japonicus Houtt., named “Yimucao” and “Chongweizi”, respectively, in Chinese, have been widely used in China as gynecological medicines. The components of the essential oils obtained by hydrodistillation were investigated by GC-MS. The antibacterial activity of the essential oils was determined by micro-dilution assay. The results showed large variations in the chemical composition and antibacterial activity of the oils. The oil of “Yimucao” showed antibacterial activity against various Gram-positive bacteria and consisted mainly of sesquiterpenes and diterpenes, with phytone, phytol, caryophyllene oxide and β-caryophyllene being the most significant constituents, whereas the oil of “Chongweizi”, mainly made up of bornyl acetate and aliphatic hydrocarbons, was inactive in the antibacterial assay. Further study of the main compounds in “Yimucao oil” showed that β-caryophyllene had wide-spectrum activity against Gram-positive bacteria.
The effect of hydrodistillation techniques on yield, kinetics, composition and antimicrobial activity of essential oils from flowers of Lavandula officinalis L.
Stanojevi? Ljiljana,Stankovi? Mihajlo,Caki? Milorad,Nikoli? Vesna
Hemijska Industrija , 2011, DOI: 10.2298/hemind110129047s
Abstract: The essential oils from flowers of Lavandula officinalis L. (L. officinalis L. = L. angustifolia Mill.) were obtained by two hydrodistillation techniques: standard (technique I) and modified (technique II) Clevenger hydrodistillation. The yield, hydrodistillation kinetics, composition and antimicrobial activity of essential oils were investigated. The higher yield of oil was obtained by hydrodistillation technique II. The new analytical hydrodistillation kinetics model of essential oil from Lavandulae flowers was defined. The essential oil composition was analyzed by gas chromatography-mass spectroscopy (GC-MS). There are differences in chemical compositions of the oils obtained by different techniques. Antimicrobial activity of essential oil obtained by technique I and II against Salmonella enteritidis, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, Candida albicans and Aspergillus niger is the same, while the activity against Escherichia coli and Pseudomonas aeruginosa is slightly different.
Chemical composition, antibacterial and antifungal activity of the essential oils of Cotinus coggygria from Serbia
MIROSLAV NOVAKOVIC,IVAN VUCKOVIC,PEDJA JANACKOVIC,MARINA SOKOVIC
Journal of the Serbian Chemical Society , 2007,
Abstract: Essential oils from leaves with young branches of Cotinus coggygria Scop. from two localities in Serbia (Deliblatska pescara and Zemun), obtained by hydrodistillation, were analysed by GC–MS. Thirty-one component were identified from both oils and among them monoterpenic hydrocarbons were the dominant class (87.4 and 93.1 %). The dominant constituent in both essential oils was limonene (47.0 and 39.2 %). Both oils were also tested for antibacterial and antifungal activities. In comparison to streptomycin, both oils showed slightly higher activity (against most Gram-positive bacteria) in the disc diffusion method and slightly lower activity when the microdilution method was employed. They also exhibited antifungal potential higher than that of the commercial fungicide bifonazole.
Comparison of Microwave-Assisted and Conventional Hydrodistillation in the Extraction of Essential Oils from Mango (Mangifera indica L.) Flowers  [PDF]
Hong-Wu Wang,Yan-Qing Liu,Shou-Lian Wei,Zi-Jun Yan,Kuan Lu
Molecules , 2010, DOI: 10.3390/molecules15117715
Abstract: Microwave-assisted hydrodistillation (MAHD) is an advanced hydrodistillation (HD) technique, in which a microwave oven is used in the extraction process. MAHD and HD methods have been compared and evaluated for their effectiveness in the isolation of essential oils from fresh mango (Mangifera indica L.) flowers. MAHD offers important advantages over HD in terms of energy savings and extraction time (75 min against 4 h). The composition of the extracted essential oils was investigated by GC-FID and GC-MS. Results indicate that the use of microwave irradiation did not adversely influence the composition of the essential oils. MAHD was also found to be a green technology.
Extraction of essential oils from lime (Citrus latifolia Tanaka) by hydrodistillation and supercritical carbon dioxide
Atti-Santos, Ana Cristina;Rossato, Marcelo;Serafini, Luciana Atti;Cassel, Eduardo;Moyna, Patrick;
Brazilian Archives of Biology and Technology , 2005, DOI: 10.1590/S1516-89132005000100020
Abstract: in this work lime essential oils were extracted by hydrodistillation and supercritical carbon dioxide. in the case of hydrodistillation, the parameters evaluated were extraction time and characteristics of the plant material. in supercritical extraction, the parameters evaluated were temperature, pressure, co2 flow, extraction time and material characteristics. considering citral content, the best results for hydrodistillation were obtained with a distillation time of 3 hours using whole peels. the best results for supercritical extraction were found using 60oc, 90 bar, at a co2 flow rate of 1 ml/ min for 30 minutes using milled peels. the best yields of lime oil were obtained by hydrodistillation (5.45% w/w) and supercritical extraction (7.93% w/w) for milled peels.
Chemical Composition and Antibacterial Activity of the Essential Oils of Callistemon citrinus and Callistemon viminalis from South Africa  [PDF]
Opeoluwa O. Oyedeji,Oladipupo. A. Lawal,Francis. O. Shode,Adebola. O. Oyedeji
Molecules , 2009, DOI: 10.3390/molecules14061990
Abstract: The chemical composition and the antibacterial activity of the essential oils obtained by hydrodistillation from the leaves of Callistemon citrinus and Callistemon viminalis were analyzed by GC and GC/MS. Twenty-four and twelve components were identified for C. citrinus and C. viminalis, representing 92.0% and 98.3% of the total oils. The major components of C. citrinus and C. viminalis were 1,8-cineole (61.2% and 83.2%) and α-pinene (13.4% and 6.4%), respectively. The in vitro antibacterial activity of the essential oils was studied against 12 bacteria strains using disc diffusion and broth microdilution methods. The oils exhibited strong zone of inhibitions against some bacteria such as S. faecalis (20.3-24.0 mm), both strains of S. aureus (23.0-26.3 mm), B. cereus (17.3-19.0 mm) and S. macrcesens (11.3-23.7 mm) when compared to standard antibiotics gentamycin and tetracycline used as controls. Expect for P. aeruginosa and S. macrcescens, the MIC values of both essential oils ranged from 0.31-2.50 mg/mL.
Comparative Study of Essential Oils Extracted from Algerian Myrtus communis L. Leaves Using Microwaves and Hydrodistillation  [PDF]
Baya Berka-Zougali,Mohamed-Amine Ferhat,Aicha Hassani,Farid Chemat,Karim S. Allaf
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms13044673
Abstract: Two different extraction methods were used for a comparative study of Algerian Myrtle leaf essential oils: solvent-free-microwave-extraction (SFME) and conventional hydrodistillation (HD). Essential oils analyzed by GC and GC-MS presented 51 components constituting 97.71 and 97.39% of the total oils, respectively. Solvent-Free-Microwave-Extract Essential oils SFME-EO were richer in oxygenated compounds. Their major compounds were 1,8-cineole, followed by α-pinene as against α-pinene, followed by 1,8-cineole for HD. Their antimicrobial activity was investigated on 12 microorganisms. The antioxidant activities were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH ?) radical scavenging method. Generally, both essential oils showed high antimicrobial and weak antioxidant activities. Microstructure analyses were also undertaken on the solid residue of myrtle leaves by Scanning Electronic Microscopy (SEM); it showed that the SFME-cellular structure undergoes significant modifications compared to the conventional HD residual solid. Comparison between hydrodistillation and SFME presented numerous distinctions. Several advantages with SFME were observed: faster kinetics and higher efficiency with similar yields: 0.32% dry basis, in 30 min as against 180 min for HD.
In vitro antibacterial activity of some plant essential oils
Seenivasan Prabuseenivasan, Manickkam Jayakumar, Savarimuthu Ignacimuthu
BMC Complementary and Alternative Medicine , 2006, DOI: 10.1186/1472-6882-6-39
Abstract: The selected essential oils were screened against four gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris) and two gram-positive bacteria Bacillus subtilis and Staphylococcus aureus at four different concentrations (1:1, 1:5, 1:10 and 1:20) using disc diffusion method. The MIC of the active essential oils were tested using two fold agar dilution method at concentrations ranging from 0.2 to 25.6 mg/ml.Out of 21 essential oils tested, 19 oils showed antibacterial activity against one or more strains. Cinnamon, clove, geranium, lemon, lime, orange and rosemary oils exhibited significant inhibitory effect. Cinnamon oil showed promising inhibitory activity even at low concentration, whereas aniseed, eucalyptus and camphor oils were least active against the tested bacteria. In general, B. subtilis was the most susceptible. On the other hand, K. pneumoniae exhibited low degree of sensitivity.Majority of the oils showed antibacterial activity against the tested strains. However Cinnamon, clove and lime oils were found to be inhibiting both gram-positive and gram-negative bacteria. Cinnamon oil can be a good source of antibacterial agents.The spread of drug resistant pathogens is one of the most serious threats to successful treatment of microbial diseases. Down the ages essential oils and other extracts of plants have evoked interest as sources of natural products. They have been screened for their potential uses as alternative remedies for the treatment of many infectious diseases [1]. World Health Organization (WHO) noted that majority of the world's population depends on traditional medicine for primary healthcare. Medicinal and aromatic plants which are widely used as medicine and constitute a major source of natural organic compounds.Essential oils have been shown to possess antibacterial, antifungal, antiviral insecticidal and antioxidant properties [2,3]. Some oils have been used in cancer treatment [4]. Some oth
Antibacterial Effect of Five Zingiberaceae Essential Oils  [PDF]
Krittika Norajit,Natta Laohakunjit,Orapin Kerdchoechuen
Molecules , 2007, DOI: 10.3390/12082047
Abstract: Essential oil obtained by hydrodistillation and two different solvent extractions (petroleum ether and ethanol) from five Zingiberaceae species: ginger (Zingiber officinale Roscoe.), galanga (Alpinia galanga Sw.), turmeric (Curcuma longa L.), kaempferia (Boesenbergia pandurata Holtt.) and bastard cardamom (Amomum xanthioides Wall.) was characterized. Volatile components of all extracts were analyzed by gas chromatographymass spectrometry (GC-MS). The major components of ginger, turmeric, galangal, bastard cardamom and kaempferia were zingiberene, turmerone, methyl chavicol, and γ-terpinene, respectively. Their antibacterial effects towards Escherichia coli, Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes were tested by a disc diffusion assay. Essential oil of kaempferia and bastard cardamom obtained by hydrodistillation extraction could inhibit growth of all tested bacteria. Essential oil of ginger extracted by hydrodistillation had the highest efficiency against three positive strains of bacteria (S. aureus, B. cereus and L. monocytogenes), with a minimum concentration to inhibit B. cereus and L. monocytogenes of 6.25 mg/mL.
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