Chemical composition and in vitro antimicrobial activities of the essential oils from endemic Psiadia species growing in mauritius

The composition of the leaf oils, obtained by hydrodistillation, of five endemic Psiadia species of the Asteraceae family were studied by GC/MS on both polar and non-polar columns. The analysis showed that the volatile components of the oils were made up essentially of monoterpenes, sesquiterpenes, aliphatics and other shikimic acid derivatives. With respect to the non-volatile components, great variations were observed: P. lithospermifolia contained (E)-isoasarone (51.5%); P. penninervia: eugenol (5.1%); P. terebinthina: eugenyl-acetate (4.0%); P. viscosa: pentyl-4-(1-methylethyl benzoate) (25.8%); P. arguta: isoeugenol (56.5%). In vitro antimicrobial assays using the agar-well diffusion method, revealed that most of the oils were not very active against the tested microorganisms except for that of P. lithospermifolia, which significantly inhibited the growth of Bacillus cereus, Staphylococcus aureus and Pseudomonas aureofaciens, Aspergillus ochraceus, Candida pseudotropicalis, Kluyveromyces lactis and Fusarium moniliforme. This activity has been attributed to the presence of delta-elemene, (E)-farnesene, alpha-curcumene, selina-4,7(11)-diene, (E,Z)-alpha-farnesene, beta-bisabolene some of which have established antimicrobial profiles. Likewise, the fungi toxic action of the oil of P. arguta against Aspergillus ochraceus, Candida pseudotropicalis, and Fusarium moniliforme, may be attributed to the presence of isoeugenol, eugenol being known to be mycotoxic especially against Aspergillus species.     

The essential oils chemical compositions and antimicrobial,antioxidant activities and toxicity of three Hyptis species

Abstract

Context: Hyptis suaveolens (Linn.) Poit., Hyptis rhomboidea Mart. et Gal., and Hyptis brevipes Poit., are three species of Hyptis Jacq. (Lamiaceae). Hyptis suaveolens is used for the treatment of fever, headache, gastrointestinal bloating and rheumatism in the traditional folk medicine; Hyptis rhomboidea for hepatitis, ulcer and swollen poison; and Hyptis brevipes for asthma and malaria.

Objective: To characterize chemical compositions of the oils from three Hyptis species and evaluate their potential antimicrobial, radical scavenging activities and toxicities against brine shrimp.

Materials and methods: The oils were obtained by hydrodistillation, and their chemical compositions were investigated by gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentrations (MICs) were determined using the tube double-dilution technique. The antioxidant activities were investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and toxicities by the brine shrimp bioassay.

Results: Forty-seven, 33 and 28 constituents of oils isolated, respectively, from H. suaveolens, H. rhomboidea and H. brevipes were identified. Among the essential oils, the strongest antioxidant activity was exhibited by H. brevipes with an SC₅₀ value of 2.019?±?0.25?μg?mL^?1. The H. brevipes oil exhibited the strongest antimicrobial activity (3.125–6.25?μg?mL^?1) on pathogens employed in the assay. They all showed significant toxicities with median lethal concentration (LC₅₀) values of 62.2?±?3.07?μg?mL^?1, 65.9?±?6.55?μg?mL^?1 and 60.8?±?9.04?μg?mL^?1, respectively.

Discussion and conclusions: The three Hyptis species oils possess strong antimicrobial activities and toxicities. Hyptis rhomboidea and H. brevipes showed considerable antioxidant activity compared to the positive control.     

Chemical composition,antioxidant and antibacterial activities of essential oils from Ferulago angulata

Context: Ferulago angulata Boiss. (Apiaceae), a perennial aromatic herb, grows wild in Iran. The aerial parts of F. angulata are used as a flavouring in foods, especially dairy foods by indigenous people in western and southwestern Iran.

Objective: This study investigates variation in chemical compositions, antioxidant and antibacterial activities of the essential oils from F. angulata collected from natural habitats in the alpine regions of southwestern Iran.

Materials and Methods: The antimicrobial activity, minimum inhibitory concentration (MIC) and minimum bactericidal (MBC) of the essential oils were evaluated against four bacteria (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus and Salmonella typhimurium). Antioxidant activity of the oils was determined by DPPH assay.

Results: The essential oils were analyzed by GC-FID and GC/MS, which 49 volatile components were identified. There were significant differences between the various populations for oil yield and some main compounds. The major constituents of the essential oils from F. angulata were α-pinene, and cis-β-ocimene. The MICs of the essential oils were within concentration ranges from 62 to 250?μg/mL and the respective MBCs were 125 to?>?500?μg/mL. Generally, the oils from F. angulata indicated weak to moderate inhibitory activities against bacteria, especially against Listeria monocytogenes. The highest antioxidant activity was obtained from the oil of the Kallar population (IC₅₀ value_?=_?488?μg/mL) and BHT as positive control (IC_50? value =_?321?μg/mL).

Discussion and conclusion: The essential oil of F. angulata could be serving as a potential source of α-pinene and cis-β-ocimene for use in the food, cosmetic and pharmaceutical industries.     

Essential oils composition in two Rosmarinus officinalis L. varieties and incidence for antimicrobial and antioxidant activities

The essential oil composition of Rosmarinus officinalis var. typicus and var. troglodytorum endemic to Tunisia, and growing wild in different bioclimates, was determined by GC and GC–MS. Oils were assessed for their antimicrobial and antioxidant activity. A variation of the chemical composition attributed to varieties rather than to bioclimates was revealed. 1.8-Cineole (47.2–27.5%) and camphor (12.9–27.9%) were identified as the main constituents of var. typicus and var. troglodytorum, respectively. The principal component analysis performed on oil constituents for all the populations allowed the distinction of two distinct population groups in accordance to the varietal subdivision. Based on the determination of the diameter of inhibition and the determination of the minimum inhibitory concentration, a low to moderate antimicrobial activity according to oils was revealed against eight bacteria tested. However, oils from var. troglodytorum showed higher bactericidal effect than those from var. typicus. The oils’ antioxidant activity, determined by 1,1-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric reducing (FRAP) assay and β-carotene bleaching test, was relatively high. The highest activity was found in oils from var. troglodytorum and in one population of var. typicus from the upper semi-arid bioclimate.     

Analysis of the essential oil of Origanum dubium growing wild in Cyprus. Investigation of its antioxidant capacity and antimicrobial activity

The volatile composition of Origanum dubium in two different maturation stages has been studied. The essential oils were obtained by hydrodistillation in a modified Clevenger-type apparatus, and their analyses were performed by GC and GC-MS. Identification of the components was made by comparison of mass spectra and retention indices with literature records and by co-chromatography with authentic compounds. Carvacrol was shown to be the main constituent. The essential oils were evaluated for antimicrobial activity and proved to be active against all tested microorganisms. Furthermore, their potential antioxidant activity was investigated and found to be significant in scavenging O2-. The samples were further evaluated for inhibition of soybean lipoxygenase LOX and showed high inhibitory activity.     

Chemical constituents and antimicrobial activities of the essential oils from Sedum pallidum var. bithynicum and S. spurium grown in Turkey

Chemical compositions of the essential oil of Sedum pallidum Bieb. var. bithynicum (Boiss.) and S. spurium Bieb. (Crassulaceae) from Turkey were investigated by GC-MS, and antimicrobial activity of the oil samples were assessed against Gram-positive/negative bacteria and yeast-like fungi. Thirty-eight and thirty-five components were identified in the essential oils and the main components of these species were found to be caryophyllene oxide from S. pallidum var. bithynicum and hexahydrofarnesyl acetone from S. spurium in the ratios of 12.8% and 15.7%, respectively. The isolated essential oils of the plants showed low antimicrobial activity against Gram-negative/positive bacteria and yeast-like fungi, having the MIC values of 500-2000?μg/mL. Antibacterial activity was not observed against Bacillus cereus.     

小蓟中挥发油成分的分析及其抑菌与止血作用的研究

目的 分析小蓟的花、叶和茎中挥发油的化学成分及其抑菌、止血作用.方法 采用超临界二氧化碳萃取,应用GC-MS法鉴定挥发油的化学成分,考察其体外抗菌、止血的活性.结果 共鉴定166个化合物,花的挥发油中主要有2-乙氧基-3-氯丁烷(16.68％)、二十八烷(12.96％)、甲苯(7.71％)等;叶的挥发油中主要有1,1-二乙氧基乙烷(18.90％)、二十八烷(13.13％)、2,3-丁二醇(13.00％)、二十五烷(10.00％)等;茎的挥发油中主要有甲氧基苯基肟(27.05％)、十六烷酸(14.48％)、3-癸炔-2-醇(12.84％)、仲丁基醚(11.05％)、十四烷酸(10.12％)等.花、叶和茎中不同萃取挥发油对特定病原菌有特殊抑菌效果,其MIC =0.031 mg·mL-1.茎的高剂量挥发油可明显缩短出血和凝血的时间.结论 花、叶和茎中挥发油的差异较大,含抑菌和止血成分.     

Chemical composition, antimicrobial and antioxidant activities of essential oil from Gnaphlium affine

The chemical composition of the essential oil from Gnaphlium affine was determined, and its antimicrobial and antioxidant activities were evaluated. Twenty-four compounds, representing 94.95% of the amount of total oil, were identified by gas chromatography-mass spectrometry (GC-MS) analysis. Main constituents of the essential oil were found to be eugenol (18.24%), linalool (10.62%), trans-caryophyllene (8.86%), α-terpineol (5.97%), p-cymene (5.75%), hexadecanoic acid (5.63%), γ-cadinene (4.98%), δ-cadinene (4.22%), α-humulene (3.22%), and (−)-β-elemene (3.15%). The essential oil revealed a remarkable antimicrobial effect against the tested food-borne microorganisms with the MIC and MBC values in the ranges of 0.2-1.56 μg/ml and 0.39-3.13 μg/ml, respectively. The essential oil showed a potent antioxidant activity in ABTS radical scavenging, lipid peroxidation and reducing power assay. It was suggested that the essential oil from G. affine may be a new potential source as natural antimicrobial and antioxidant agents applied in food systems.     

Variation of alkaloid contents and antimicrobial activities of Papaver rhoeas L. growing in Turkey and northern Cyprus

Context: Papaver rhoeas L. (Papaveraceae) corn poppy, widely distributed in Turkey, is used to make a cough syrup for children, as a tea for disturbed sleep, for pain relief and as a sedative in folk medicine.

Objective: Samples of P. rhoeas collected from eight different locations in Turkey and three from northern Cyprus were investigated for their alkaloid content and screened for their antimicrobial activities.

Materials and methods: From the aerial parts of P. rhoeas samples, alkaloids were isolated by column and preparative thin-layer chromatography. The alkaloids were identified by comparing their spectral data (UV, IR and ¹H-NMR) and TLC Rf values with those of authentic samples. The antimicrobial study was carried out by microbroth dilution technique against six strains of bacteria and three strains of fungi.

Results: Twelve different alkaloids belonging to proaporphine (mecambrine), aporphine (roemerine), promorphinan (salutaridine), protopine (coulteropine and protopine) and rhoeadine (epiglaucamine, glaucamine, glaudine, isorhoeadine, isorhoeagenine, rhoeadine and rhoeagenine) groups were isolated. The most significant activity was observed with the alkaloid extract of P8 against Staphylococcus aureus with a MIC value of 1.22?μg/mL and against Candida albicans with a MIC value of 2.4?μg/mL.

Discussion: The results indicate that P. rhoeas samples (P8 and P9), which contain roemerine as their major alkaloid, were the most active extracts.     

Antigenotoxic and antioxidant activities of Pituranthos chloranthus essential oils

The SOS-chromotest in Escherichia coli is a widely used bacterial genotoxicity assay to test potential carcinogens. The aim of this work is to evaluate the genotoxic and antigenotoxic activities of essential oils obtained from aerial parts of Pituranthos chloranthus. The tested essential oils were not genotoxic towards both E. coli PQ37 and PQ35 strains. These essential oils reduced significantly Nifuroxazide and H(2)O(2)-induced genotoxicity. Essential oils showed a protective effect against damages induced by radicals, obtained from the photolysis of H(2)O(2), on DNA plasmid through free radical scavenging mechanisms. The scavenging capacity of these essential oils was also estimated by evaluating the inhibition of ABTS(+.) radical.     

Free radical scavenging and antiacetylcholinesterase activities of Origanum majorana L. essential oil

In the present study, Origanum majorana L. essential oil (EO) was analyzed by gas chromatography-mass spectrometry (GC-MS) and evaluated for free radical scavenging and anticholinesterase activities. GC-MS analysis revealed the presence of 4-terpineol (29.97%), γ-terpinene (15.40%), trans-sabinene hydrate (10.93), α-terpinene (6.86%), 3-cycolohexene-1-1 methanal,a,a4-trimethyl-,(S)-(CAS) (6.54%), and sabinene (3.91%) as main constituents. Origanum majorana L. EO exhibited concentration-dependent inhibitory effects on 2,2'-diphenylpicrylhydrazyl (DPPH(?)), hydroxyl radical, hydrogen peroxide, reducing power, and lipid peroxidation with IC(50) values of 58.67, 67.11, 91.25, 78.67, and 68.75 μg/mL, respectively; while the IC(50) values for the standard trolox were noted to be 23.95, 44.97, 51.30, 42.22, and 52.72 μg/mL, respectively. Interestingly, cholinesterase inhibitory activity was also found with IC(50) values of 36.40 μg/mL. We can conclude that the marjoram EO has a significant potential to be used as a natural antioxidant and anti-AChE.     

Antimicrobial and antioxidant activities of three Mentha species essential oils

The present study describes the antimicrobial activity and free radical scavenging capacity (RSC) of essential oils from Mentha aquatica L., Mentha longifolia L., and Mentha piperita L. The chemical profile of each essential oil was determined by GC-MS and TLC. All essential oils exhibited very strong antibacterial activity, in particularly against Esherichia coli strains. The most powerful was M. piperita essential oil, especially towards multiresistant strain of Shigella sonei and Micrococcus flavus ATTC 10,240. All tested oils showed significant fungistatic and fungicidal activity [expressed as minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values, respectively], that were considerably higher than those of the commercial fungicide bifonazole. The essential oils of M. piperita and M. longifolia were found to be more active than the essential oil of M. aquatica. Especially low MIC (4 microL/mL) and MFC (4 microL/mL) were found with M. piperita oil against Trichophyton tonsurans and Candida albicans (both 8 microL/mL). The RSC was evaluated by measuring the scavenging activity of the essential oils on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and OH radicals. All examined essential oils were able to reduce DPPH radicals into the neutral DPPH-H form, and this activity was dose-dependent. However, only the M. piperita oil reduced DPPH to 50 % (IC50 = 2.53 microg/mL). The M. piperita essential oil also exhibited the highest OH radical scavenging activity, reducing OH radical generation in the Fenton reaction by 24 % (pure oil). According to GC-MS and TLC (dot-blot techniques), the most powerful scavenging compounds were monoterpene ketones (menthone and isomenthone) in the essential oils of M. longifolia and M. piperita and 1,8-cineole in the oil of M. aquatica.     

Antimicrobial activity and chemical composition of some essential oils

In this study the composition and antimicrobial properties of essential oils obtained from Origanum onites, Mentha piperita, Juniperus exalsa, Chrysanthemum indicum, Lavandula hybrida, Rosa damascena, Echinophora tenuifolia, Foeniculum vulgare were examined. To evaluate the in vitro antibacterial activities of these eight aromatic extracts; their in vitro antimicrobial activities were determined by disk diffusion testing, according to the NCCLS criteria. Escherichia coli (ATTC 25922), Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATTC 27853 were used as standard test bacterial strains. Origanum onites recorded antimicrobial activity against all test bacteria, and was strongest against Staphylococcus aureus. For Rosa damascena, Mentha piperita and Lavandula hybrida antimicrobial activity was recorded only to Staphylococcus aureus. Juniperus exalsa, and Chrysanthemum indicum exhibited antibacterial activities against both Staphylococcus aureus and Escherichia coli. We also examined the in vitro antimicrobial activities of some components of the essential oils and found some components with antimicrobial activity.     

Rapid,cost-effective and organic solvent-free production of biologically active essential oil from Mediterranean wild Origanum syriacum

BackgroundOriganum syriacum (O. syriacum) is a very popular edible and medicinal plant in the East Mediterranean countries. The aims of the current study were to use microwave-ultrasonic assisted hydrodistillation (MUAHD) method to produce essential oils (EOs) from wild O. syriacum samples collected from four different geographical areas in The West Bank using water as a solvent, determine the phytochemical profile using GC-MS analysis and assess their antioxidant and antibacterial potential.MethodsEssential oils were produced using MUAHD method. Gas chromatography coupled with mass spectrometer detector (GC-MS) was employed for phytochemical analysis. In vitro antibacterial and antioxidant potentials were carried out.ResultsDifferences in the EOs yield among the four Origanum samples were observed. GC-MS analysis of EOs revealed terpenes as the major constituents; monoterpenes (22–56%) and oxygenated monoterpenes (28–57%). Thymol, α-terpinene and carvacrol represent the bulk of all phytochemicals detected by GC-MS analysis. γ-Terpinene-rich EOs, exhibited the highest antioxidant capacity. Thymol-rich EOs were found to be most effective against Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus (MRSA) (MIC 390 µg/mL). Alpha-terpinene-rich chemotype EOs exhibited the highest inhibitory effect of Pseudomonas aeruginosa (MIC of 1560 µg/mL). Interestingly, γ-terpinene-rich EO showed promising antibacterial properties against Enterococcus faecium (MIC 97 µg/mL) and a powerful anti-oxidant effect (91.45% ±2.30).ConclusionThe current study supports the use of MUAHD as a time-saving, cost-effective, environment-friendly method for production of high quality O. syriacum EO for potential use as a natural complementary treatment and in the prevention of bacterial infections as well as oxidation by free radicals without compromising the quantity.     

Chemical composition,antimicrobial and antioxidant activities of the essential oils of Sideritis erythrantha Boiss. and Heldr. (var. erythrantha and var. cedretorum P.H. Davis) endemic in Turkey

In the present study, chemical compositions, antimicrobial and antioxidant activities of the essential oils of Sideritis erythrantha var. erythrantha (SE) and Sideritis erythrantha var. cedretorum (SC), which are endemic taxa in Turkey, were investigated. The essential oils obtained by hydrodistillation were analyzed by gas chromatography–mass spectrometry (GC–MS). α-Pinene was the major component of the essential oils of SC and SE. SC essential oil was as effective as antibiotic against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus faecalis (VRE), ampicillin resistant Haemophilusinfluenzae and vancomycin sensitive E. faecalis. Similarly, SE essential oil was also as effective as antibiotic against VRE and ampicillin resistant H. influenzae. Antioxidant activities of the essential oils of SC and SE were determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH), β-carotene/linoleic acid and reducing power. Both essential oils exhibited weak antioxidant activity. This is the first report on antimicrobial and antioxidant activities of the essential oils of SC and SE.     

Chemical composition and antimicrobial activity of the essential oils of Pistacia lentiscus var. chia

The chemical composition of the three essential oils obtained by steam distillation of the mastic gum, leaves and twigs of Pistacia lentiscus var. chia, was studied by GC/MS. Sixty nine constituents were identified from the oils. alpha-Pinene, myrcene, trans-caryophyllene and germacrene D were found to be the major components. The in vitro antimicrobial activity of the three essential oils and of the resin (total, acid and neutral fraction) against six bacteria and three fungi is reported.     

香薷挥发油成分的研究

本文用GLC等方法鉴定和测定了海州香薷挥发油中对聚繖花素(10.43%)、百里香酚(30.05%)、香荆芥酚(33.39%)、α-反式-香柠檬烯(1.64%)等12个成分,并与川香薷挥发油的成分进行了分析比较。     

Chemical composition and mosquito larvicidal activities of Salvia essential oils

Context: Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. In this context, essential oils have received much attention as potentially useful bioactive compounds against insects. Therefore, our present study aimed to evaluate the efficacy of essential oils from the aerial parts of Salvia elegans Vahl, Salvia dorisiana Standl., Salvia splendens Sello ex J.A. Schult Blue Ribbon, and S. splendens Sello ex J.A. Schult Scarlet Sage Red (Lamiaceae) against the fourth instar larvae of Aedes albopictus Skuse (Diptera: Culicidae).

Objective: The mosquito larvicidal activities of the essential oils and chemical composition of four taxa of Salvia are investigated in this article for the first time.

Materials and methods: Chemical compositions of essential oils obtained from four taxa of Salvia were analyzed by gas chromatography-mass spectrometry (GC-MS), GC-FID, and the effects of essential oils on fourth instar larvae of A. albopictus were investigated.

Results: The main components identified from each Salvia essential oils were as follows: spathulenol (38.73%) and caryophyllene (10.32%) from S. elegans; ledol (45.8%) and 4,4'-[(p-phenylene)diisopropylidene]diphenol (17.38%) from S. dorisiana; β-cubebene (22.9%), and caryophyllene (12.99%) from S. splendens Blue Ribbon; phytol (41.46%) and cyclooctasulfur (24.88%) from S. splendens Scarlet Sage Red. The essential oils of S. elegans and S. splendens Blue Ribbon had excellent inhibitory larvicidal effect against A. albopictus larvae, and their LC₅₀ values in 24?h were 46.4?ppm (LC₉₀?=?121.8?ppm) and 59.2?ppm (LC₉₀?=?133.0?ppm), respectively.

Discussion and conclusion: These findings demonstrate that the essential oils of these Salvia species could be considered as the powerful candidates to bring about useful botanicals so as to prevent the resurgence of mosquito vectors.