Thymol Content Research Articles

Foliar spraying of salicylic acid induced accumulation of phenolics, increased radical scavenging activity and modified the composition of the essential oil of water stressed Thymus vulgaris L.

Polyphenolic compounds are considered valuable secondary plant metabolites owing to the myriad of biological activities they exert. This study aimed to investigate the effect of applying various concentrations of the plant growth regulator, salicylic acid (SA), on Thymus vulgaris L. while subjecting the plant to decreasing amounts of irrigation water. The following parameters were monitored; total polyphenolic and flavonoid content, yield and composition of the essential oil, and antioxidant activity of the alcoholic extracts. Drought alone significantly (P < 0.05) increased the polyphenolic and flavonoid content, yield of the essential oil and antioxidant activity. The total flavonoid content in control plants was 6.1 ± 0.3 mg/gm dry weight calculated in terms of rutin equivalent. However, in drought stressed plants, (irrigated at 25% of the field capacity) sprayed with 3 mM SA, the flavonoid content increased to 32.1 ± 0.1 mg/gm dry weight calculated in terms of rutin equivalent. Moreover, the total phenolic content increased from 8.5 ± 0.3 to 68.5 ± 1.2 mg/gm dry weight calculated in terms of gallic acid in the same test plants. Radical scavenging activity, using DPPH assay, was measured for the different plant treatments. A decrease from 74.4 ± 0.4 μg/ml to 36.6 ± 0.9 μg/ml of IC50 was recorded in the drought stressed plants (25% FC) sprayed with 3 mM SA compared with the control plants. The variability in polyphenolic composition between the control plants and plants with the highest total polyphenolic content was investigated by UPLC-ESI-MS/MS. Rosmarinic acid was detected as the major component in samples from both treatments, with a higher percentage observed upon subjecting the plant to the test conditions (25% FC and sprayed with 3 mM SA). The highest yield of the essential oil (1 ± 0.06 %v/w) was obtained from drought stressed plants (25% FC) sprayed with 2 mM SA. GC/MS analysis of oil samples revealed that the Thymol content increased with drought stress, while that of p-cymene decreased. However, an increase of p-cymene was witnessed as a result of SA spraying.

Metabolic profiles of groundnut (Arachis hypogaea L.) genotypes differing in Sclerotium rolfsii reaction

A total of 60 compounds of known structure, comprising sugars, sugar alcohols, fatty acids, amino acids, organic acids, phenols and sterols were identified in stem extracts of groundnut using GC-MS. Sugars and fatty acids were predominant in stem extracts as compared to other metabolites. Distinguished metabolite patterns were observed in control and 96 h after infection (h.a.i.). Succinic acid, pentitol, scopolin, D-glucose and D-turanose, myo-inositol, fructose and mannitol were observed to be higher in control plants, whereas, D-ribopyranoside, thymol, pentadecanoic acid and octadecanoic acid increased at 24 hai than that of control. Interestingly, phenol related compounds such as phenol, hydroquinone, guaicol-.beta.-d-glucopyranoside, scopolin were also found lower in non-infected stems of TG37A. Moreover, tolerant genotypes (CS 319 and CS 19) had higher content of Thymol-.beta.-d-glucopyranoside, pentitol, D-glucose, D-turanose, scopolin and hydroquinone than that of moderately tolerant and susceptible genotypes. Sugar profiles using Ion chromatography revealed that glucose content decreased in moderately susceptible and susceptible genotype after S. rolfsii infection. Both constitutive and induced levels of cinnamic acid was observed higher in resistant genotypes than that of susceptible ones which was further supported by phenylalanine ammonia lyase activity. Thus, our study demonstrates the biological role of metabolites specifically sugars, phenolics and fatty acids in plant defense responses.

Morpho-physiological and phytochemical traits of (Thymus daenensis Celak.) in response to deficit irrigation and chitosan application

Thymus daenensis Celak. is an aromatic herb used as a popular medicine and its natural products in the form of extracts and essential oil have significant economic values in Iran. We hypothesized that spraying plants grown under deficit irrigation system with chitosan can be considered as an applicable method to enhance essential oil and antioxidant activity in thyme. Response of thyme to three irrigation regimes including well-watered, moderate stress, and severe stress along with three levels of chitosan application rates 0, 200, and 400 μL L−1 was evaluated in a 2-year study in 2014 and 2015. Drought stress condition significantly shortened phenologic stages, more specifically in the first (establishment) year. All growth parameters were reduced dramatically as drought stress intensified. Imposing even moderate stress reduced leaf area as much as 59 and 44% in the first year and the second year, respectively. Biomass yield of plants grown under severe drought stress decreased substantially, whereas essential oil content and the share of thymol in thyme oil which possesses the greatest degree of biological activity improved. Maximum oil yield (1.50 g plant−1) was obtained from plants under mild drought stress when sprayed with 400 μL L−1 chitosan in the second year when plants were well-established. Foliar applications of chitosan reduced the adverse effect of water deficit on oil yield and improved thymol content of the essential oil. Chitosan also increased secondary metabolites including α-terpinene, p-cymene, γ-terpinene, thymol, carvacrol and β-caryophyllene. Leaf flavonoid reduced under deficit irrigation while more phenol was found in plants grown under deficit irrigation. The essential oil of thyme exhibited antioxidant property when the plants were sprayed with 400 μL L−1 chitosan. The results of this study indicated that thyme can be grown successfully under moderate stress and that application of chitosan elicitor can to some degree compensate the negative impact of deficit irrigation on its biomass and essential oil yield.

Influence of Environmental Factors on Essential Oil Variability in Origanum compactum Benth. Growing Wild in Morocco.

The present study aimed to evaluate the influence of environmental factors on essential oils (EOs) composition of Origanum compactum populations sampled all over the distribution area of the species in Morocco, and to determine the extent of the chemical profiles throughout the geographical distribution of the species. The chemical compositions were submitted to canonical correlation analysis and canonical discriminant analysis that indicated a significant relationship between oil components and some environmental factors. According to their chemical composition and edapho-climatic characteristics, two major groups of populations were differentiated. The first group was composed of samples growing in regions with humid climate, clayey, sandy, and alkaline soils. These samples showed high thymol, α-terpineol, linalool, and carvacryl methyl oxide content. The second group consisted of plants belonging to semi-arid climate, and growing at high altitudes and silty soils. These samples were characterized by high carvacrol, α-thujene, α-terpinene, and myrcene content. However, populations exposed to sub-humid climate, appeared less homogeneous and belong mainly either to the first or second group. A significant correlation between some edaphic factors (pH, K2 O content, soil texture) and the EOs yield of O.compactum plants was evidenced. In spite of the correlation obtained for the oil composition with edapho-climatic factors and the variance explained by the environmental data set, the observed EO diversity might be also genetically determined.

Changes of Thymoquinone, Thymol, and Malondialdehyde Content of Black Cumin (Nigella sativa L.) in Response to Indonesia Tropical Altitude Variation

Black cumin cultivated in many subtropical regions in the world, including Asia, Middle East, and North Africa. The most active constituent of black cumin is thymoquinone representing 18.4%–24% of the volatile oil and thymol. Data about thymoquinone and thymol came from the country of origin, but no data from tropical region. This study aimed to analyze the production of chlorophyll, thymoquinone, thymol, and malondialdehyde from black cumin cultivated at three altitudes of Indonesian tropical region. The result showed that Kuwait accession cultivated at middle altitude contains the highest levels of thymoquinone (2940.43 mg/kg), and the highest levels of thymol were found in India accession cultivated at high altitude (141.46 mg/kg). Data showed that the level of malondialdehyde at low (220 meter above sea level [masl]) and middle (560 masl) altitudes is higher than high (1.280 masl) altitude.

Relaxant effects of aqueous cold extracts of Carum copticum on smooth muscle

Background: The objective was to study the nature of relaxant effect of cold aqueous extracts of Carum copticum on rat alimentary tract and uterus.Methods: The aqueous cold extracts of Carum copticum (omum) whole seeds (OE1) or ground seeds (OE2) was prepared by leaving them (10g to 100mL) in distilled water for 4 hrs. Rat isolated tissues like stomach, duodenum, jejunum or uterus 4 cm pieces were mounted in a 20mL bath containing Tyrode solution or De Jalons at 37°C with continuous aeration. The effect of Carum copticum extracts and thymol on spontaneous activity of intestine and on acetylcholine (ACh), Histamine (H), Barium chloride (BaCl2) induced contractions or Adrenaline produced (Adr) relaxations were observed. Thymol content of omum was estimated by HPLC.Results: Omum extracts decreased or abolished spontaneous contractions of intestine but did not antagonize the contractions induced by ACh, H or relaxation induced by adrenaline. Thymol did not show any such effect. The stimulant action of BaCl2 was antagonized by aqueous cold extracts of omum similar to Papaverine.Conclusions: The relaxant effect of Carum copticum on rat intestine appears to be a direct effect on smooth muscle like papaverine.

Effect of colchicine-induced polyploidy on morphological characteristics and essential oil composition of ajowan (Trachyspermum ammi L.)

Polyploidy is an amazing evolutionary event that can be used in plant breeding to improve plant material. The present study was conducted to assess the effect of in vitro-induced polyploidy on different properties of Ajowan medicinal plant. Five different concentrations of colchicine, including 0.025, 0.05, 0.1, 0.2, and 0.5% (w/v), were applied to germinating seeds of ajowan in six different durations of exposure, including 6, 12, 24, 36, and 48 h. Chromosome counting showed successful duplication of chromosome number in tetraploid plants (2n = 4x = 36) in contrast with intact diploid plants (2n = 2x = 18). DNA content duplication in induced tetraploid plants was proved through flow cytometry analysis. The highest tetraploidy induction was achieved by applying 0.05% (w/v) colchicine for 24 h with 11.53% efficiency. The tetraploid plants achieved were larger than their diploid intact plants for plant height, leaf length, stem diameter, inflorescence length, peduncle length, and seed length characteristics. The length and width of stomata were increased in induced tetraploid plants, whereas stomata density was decreased, in contrast with initial diploid plants. Gas chromatography mass spectrometry (GC/MS) analysis showed significant increases in thymol content in essential oil of tetraploid plants (69.2%) in contrast with those of diploid plants (49.67%).

Application of Hyperosmotic Nanoemulsions in Wound Healing: Partial Thickness Injury Model in Swine.

Objective: In this work, we introduce a novel hyperosmotic nanoemulsion (HNE) topical agent for use in wound healing. These topical emulsion complexes combine a lipophilic thymol nanoemulsion with a hyperosmotic saccharide matrix. This combination has been previously shown to possess synergistic antimicrobial activity against a host of common and drug-resistant pathogens in vitro. Approach: In this study, we present additional data to assess the safety and efficacy of these emulsions in a partial thickness injury model in swine. Ten wounds sized 2 × 3.5 cm were created in 18 pigs using an electrodermatome set at a depth of 0.76 mm. The wounds were subsequently contaminated with a cocktail of Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans at 5 × 107 total colony forming unit per wound. Treatments were subdivided in the control group and emulsion concentrations at 0.0%, 0.01%, 0.03%, and 0.063% thymol content. Longitudinal metrics for wound healing included rate of reepithelialization, wound bed color measurements, amount of wound exudate, wound swab culture data, and histological examination at 4, 7, and 14 days. The cosmetics of the healed wound were obtained at day 14 with three-dimensional photogrammetry. Results: Experimental results showed that HNE reduced the wound level bacteria count by ∼0.5-1 log versus controls after 24 h. The amount of pathogen reduction was weakly correlated to the concentration of the emulsion. In addition, all HNE groups maintained a moist wound environment and showed increased fibrin formation and improved hemostatic response. Innovation: No significant difference in the rate of reepithelialization or wound closure was found between treatment concentrations and control groups. HNE treatment did not demonstrate any adverse host tissue response. Conclusion: These results suggest HNE may be a candidate for reducing wound bacterial counts without compromising reepithelialization.

Chemical Investigation on Leaf, Flower and Fruit Oils of Lantana camara from Côte d'Ivoire

The compositions of essential oil obtained from leaves, flowers and fruits of Lantana camara L. growing in wild at Cte d'Ivoire, were investigated by GC and ¹³C NMR. Thirty-seven compounds accounting for 88.3-94.5% of the oils have been identified. The leaf, flower and fruits of L. camara produced sesquitetpene-rich essential oils predominated by (E)-β-caryophyllene and a-humulene, in addition to the important content of sabinene, Pβphellandrene and thymol as monoterpenes. It was found the new chemical profiles of L. camara.

Traceability of Active Compounds of Essential Oils in Antimicrobial Food Packaging Using a Chemometric Method by ATR-FTIR

A simple and rapid Fourier Transform infrared (FTIR) spectroscopy method was developed to determine the main essential oil components (carvacrol, thymol and p-cymene) in the antimicrobial LDPE films incorporated with oregano (Origanum vulgare) and thyme (Thymus vulgaris) essential oils. The ATR-FTIR spectrum of pure active components (carvacrol, thymol and p-cymene) was characterized, and the ranges between 1125 cm-1 - 1095 cm-1, 1170 cm-1 - 1140 cm-1 and 1050 cm-1 - 1017 cm-1 were respectively used for quantitative estimation. Partial least square (PLS) analysis was used for quantitative analysis. FTIR spectroscopy with chemometrics, using the PLS-1st derivative spectra, could predict the content of active compounds accurate to an r2 greater than 0.99 and a standard error of prediction (SEP) less than 0.7. The developed method was successfully applied to predict the concentration of active compounds: carvacrol, thymol and p-cymene in oregano and thyme essential oils with results compared to those of the GC-MS method. The described non-destructive method can be applied in the industry instead of extraction, distillation and blend processes of the mentioned essential oils and can be extended to detect the content of carvacrol, thymol and p-cymene in active packaging and other commercial products.

Identification of potential therapeutic role of thymus capitatus essential oil using cellular imaging

Plant derived natural products can provide promising anti-cancer activity and can support the development of novel anti-cancer treatment strategies as cytotoxic activity towards cancer cells was observed in the recent studies in which different human cancer cell lines were exposed to plant essential oils. In our study, thyme (Thymus capitatus) essential oil analyzed by GC and GC/MS showed high content of thymol, p-cymene, carcacrol and γ-terpinene representing 62.3%, 10.9%, 6.7% and 5.1% of total oil respectively. It was tested for its potential therapeutic role by using neoplastic transformed human telomerase reverse transcriptase (hTERT) immortalized mesenchymal stem cells (hMSC- telo1) and a tumorigenic cell line; human telomerase reverse transcriptase immortalized mesenchymal stem cells which are irradiated with 2.5 Gy of gamma-rays. The hMSC- telo1 and irradiated hMSC- telo1cells were exposed to increasing concentrations of thyme essential oil in order to investigate the effects of different concentrations of thyme essential oil on the hMSC- telo1 and irradiated hMSC- telo1cells and to identify any cellular response of thyme essential oil towards these cell lines. The hMSC- telo1and irradiated hMSC- telo1cells were treated with 0.5% (v/v), 1% (v/v) and 2% (v/v) thyme essential oil. Cellular response of hMSC- telo1 and irradiated hMSC- telo1cells to thyme essential oil was evaluated for all three concentrations at different time points (0 h, 2 h, 4 h, 24 h, 72 h and 120 h) by investigating proliferation rate, viability and morphology. Our results demonstrated that there was significant effect of all three concentrations used on hMSC- telo1and irradiated hMSC- telo1cells; particularly the effect was higher on the cells treated with 0.5% (v/v) thyme essential oil. Furthermore, when cellular response at different time points were compared, it was shown that exposure time to thyme essential oil is highly important for cellular viability.

Essential Oil Chemotypes of Three Ocimum Species Found in Sierra Leone and Nigeria

Chemical composition of the essential oil of Ocimum basilicum L., O. gratissimum L. and O. americanum L. varieties found in Sierra Leone and Nigeria were determined by GC-FID and GC-MS. The antimicrobial test was evaluated by agar diffusion. The Sierra Leone and Nigeria O. americanum L. varieties were identified as the linalool chemotype and similarly, varieties of O. gratissimum L. from both countries are thymol chemotype. The high thymol content is consistent with the relative high antimicrobial activity of the O. gratissimum L oils. The Sierra Leone O. basilicum L. sample was established as the methyl eugenol chemotype while the Nigerian collection is predominantly methyl chavicol in composition. The high methyl eugenol content of the Sierra Leone collection is consistent with the observation of attraction of fruit flies to the distillate. To the best of our knowledge, there has been no report on essential oils of Ocimum species in Sierra Leone, hitherto.

Chemical Composition of the Essential Oils of Some Central Asian Nepeta Species (Lamiaceae) by GLC-MS

The chemical composition of the essential oils obtained from aerial parts of Nepeta alatavica Lipsky, N. nuda L, and N. olgae Regel (Lamiaceae), growing wild in Central Asia (Tajikistan and Uzbekistan), were analyzed by GLC and GLC-MS. The main constituents of the essential oil from N. nuda were 1,8-cineole (24.6%), 4a-α,7-β,7a-α-nepetalactone (21.0%), germacrene D (13.5%), and β-caryophyllene (12.7%), whereas those of N. alatavica were thymol (48.5%) verbenone (7.7%), and carvacrol (7.5%). In the essential oil of N. olgae the most abundant compounds were acetylcyclohexene (31.5%), 4-tridecyne (13.2%), 2-methyl cyclopentanone (6.8%) and 1,8-cineole (6.0%). The potential antioxidant activity of these essential oils was studied by using DPPH, ABTS and FRAP assays. The essential oil of N. alatavica showed the highest in vitro free radical scavenging activity, probably due to its high thymol and carvacrol content.

Essential oil variation in Iranian Ajowan (Trachyspermum ammi (L.) Sprague) populations collected from different geographical regions in relation to climatic factors

Ajowan (Trachyspermum ammi) is an industrial medicinal plant with different food and pharmaceutical applications. Essential oil yield and composition of 24 ajowan populations in different locations of Iran was investigated. The essential oil content of populations ranged from 1.68% in Yazshah to 5.55% in Yazd. According to GC–MS analysis, thymol (48.84–61.44%), γ-terpinene (26.96–19.46%) and p-cymene (15.09–20.32%) were the major components. According to hierarchical cluster and principal component analyses, two chemotypes were determined for Iranian ajowan populations, including high thymol, and high γ-terpinene and p-cymene groups. The highest correlation coefficient was between β-pinene and α-pinene (+0.709), while the highest negative correlation was between γ-terpinene and thymol (−0.896). In the present study, the climatic and soil orders of studied populations were determined. Canonical correspondence analysis (CCA) was also applied to assess the impact of geographic variation and environmental conditions on chemical variability of ajowan. Finally, it can be suggested that high essential oil and thymol content (phenolic chemotype) can be obtained in poor, undeveloped, relatively stony and shallow soil orders in arid and semi-arid conditions, while none phenolic ones needs higher humidity and soil depth that the first group.

Effect of Thyme Essential Oil Supplementation on Thymol Content in Blood Plasma, Liver, Kidney and Muscle in Broiler Chickens

The absorption and metabolism of phytogenic feed additives in poultry is studied related to the metabolism and deposition of their main compounds in tissues intended for food production. Fifty-six non-sexed Ross 308 broilers were allocated to seven dietary treatments and fed a diet containing graded levels of thyme (Thymus vulgaris L.) essential oil (EO) (0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.1%, w/w). Thymol concentration was measured in plasma, liver, kidney and breast muscle tissue using solid phase micro-extraction followed by gas chromatography/mass spectrometry. We found the highest concentrations of thymol in kidney and plasma, and the lowest in breast muscle and liver. Thymol content in plasma and kidney significantly increased when 0.05 and 0.1%, w/w, EO and in liver and breast muscle only when 0.1%, w/w, EO was added to the diet (p<0.05). Our results indicate intensive metabolism of thymol in liver and its accumulation in kidney tissue. We confirm low deposition of thymol in the muscle tissue. It is necessary to.-keep in mind the selection of a sufficient concentration of EO in the feed additive for animals without the risk of thymol residues in edible tissues.

Development and Assessment of a Gas Chromatographic Based Method for the Quantification of Thymol from Cream Based Formulation.

Herbal medicines have been used for different illnesses. However, standardization of these medicaments should be done before introducing for treatment purposes. Ajwain an essential oil, is traditionally used for neuropathic pain. To develop and assess a gas chromatographic-based method for the quantification of thymol in Ajwain essential oil, current work was performed. Both pure thymol and Ajwain creams were prepared and subjected to hydrodistillation method under temperature-controlled procedure to re-extract the applied essential oil and pure thymol. Previously, Ajwain seeds essential oil composition was analyzed and identified using GC/MS. After re-extraction, GC/FID was applied quantitatively to determine the thymol content in the Ajwain and thymol creams. The parameters represented in International Conference on Harmonization (ICH) guidelines were considered for the determination. Thymol content in a 50 g laminated tube of Ajwain cream was calculated as 2.34 g ± 0.02. Regarding the total thymol content of a 50 g laminated tube of Thymol cream (2.43 g), recovery percent for Ajwain cream was calculated as 96.29 %. Using hydrodistillation for an essential oil- containing cream sample via Clevenger proved to be a simple and convenient method to work up and extract active volatile components of such semisolid formulation. However, the extraction yield was profoundly related to the condenser temperature. The current employed determination method is introduced as a rapid and reliable method and thus, can be suggested for the quality control assessment of phytopharmaceutical semisolid preparations containing thymol and similar volatile constituents.

Statistical analysis of the associations between phenolic monoterpenes and molecular markers, AFLPs and SAMPLs in the spice plant Oregano

Summary Introduction: Molecular markers are the examples of the contribution of genome technology to medicinal plant breeding through marker-assisted selection (MAS) for pharmaceutical quality. Objective: Forty-two accessions of Origanum vulgare L. originating from Europe were evaluated to detect genomic and chemotypic polymorphisms and to discover possible associations between them. Methods: A total of 477 molecular polymorphisms including 214 AFLP (Amplified Fragment Length Polymorphism) and 263 SAMPL (Selectively Amplified Microsatellite Polymorphic Loci) were used for genotyping. Components in the essential oils were identified and quantified by gas chromatography (GC) and two major compounds (two economically important monoterpenes: carvacrol and thymol) were investigated. Results: Based on results, a relatively high correlation between chemotypic patterns and genetic markers was identified. Associations between traits of interest for essential oils (carvacrol and thymol content) and genetic markers were tested using five statistical methods including three General Linear Model (GLM) and two unified Mixed Linear Model (MLM) approaches. Significant associations were found for 3 AFLP and 20 SAMPL with three key traits including essential oil yield, carvacrol and thymol content. Conclusion: These associations can constitute a useful starting point for marker-assisted selection. Therefore, the results provide the basis for molecular breeding of O. vulgare for pharmaceutical purposes.

Effect of Vermicompost and Planting Pattern on Oil Production in Satureja sahendica L. under Competition with Pigweed (Amaranthus retroflexus L.)

The sahendi savory (Satureja sahendica Bornm.) is a native medicinal species of Iran which is subjected to extinction. Regarding to the importance of weed management and soil organic fertilization our study focused on plant growth responses to different nutrition systems and competition of redroot pigweed (Amaranthus retroflexux L.) in two planting pattern (rectangles, zigzag). Experiment was carried out in a randomized complete block design with three replications and factorial arrangement of treatments at the Ismael Abad Research Station, Qazvin Agriculture and Natural Resources Research Center on 2010 to 2012. Nutritional treatments include: NPK plus foliar application of micronutrients, four tone/ ha of vermicompost, two tone/ha vermicompost plus 40 liters/ha vermi-tea (liquid formulation of vermicompost). Pigweed density has also been studied at four levels of 0, 6, 12 and 18 plants per square meter. Effect of fertilizer treatments on essential oil percentage of sahendi savory was not significant and relative superiority of essence belonged to vermicompost fertilizer as 2 tone/ha plus 40 liters of vermi-tea .Also among the harvests second harvest was superior than first harvest. Weed treatment had no significant effect on essential oil percentage of sahendi savory. Thymol content in plots fertilized by 4 tons per hectare vermicompost was the highest value (42.95%) and had inverse relation with the p-cymen content (35.3%). Weed free condition produced the highest thymol content (45.18 %), meanwhile and the lowest amount (38.6%) were found in high weed density (18 plants per square meter).

Application of cellulose acetate for controlled release of thymol

Cellulose acetate (CA) was investigated as a carrier towards development of material with controlled release of thymol as a natural substance with strong antibacterial properties using high pressure techniques. Effect of thymol content on CA was confirmed by SEM, FTIR and DSC methods. Kinetic of thymol release from CA was tested using simulated gastric and intestinal fluids (hydrochloric acid and phosphate buffer saline). Results were correlated with Korsmeyer-Peppas and Weibull model. Depending on the thymol content and chemical nature of the release medium, the time of thymol release varied from one to three days indicating CA as a promising carrier of thymol with potential uses from medicine to agriculture. The impregnated CA showed antibacterial activity against 23 tested bacterial strains including methicillin-resistant Staphylococcus aureus (MRSA) which is particularly important bearing in mind that this strain causes fatal infections in humans and animals.

Antibacterial activity against methicillin-resistant Staphylococcus aureus of five essential oils from Algerian medicinal plants (Lamiaceae)

The susceptibility of two methicillin-resistant Staphylococcus Aureus (MRSA) and one methicillin-sensitive Staphylococcus Aureus (MSSA) to essential oils (EOs) extracted from five Algerian medicinal plants (Lamiaceae) was evaluated. Thymus fontanesii and Thymus numidicus EOs revealed a carvacrol chemical profile (62.7 and 46.8%, respectively) whereas Origanum glandulosum EO was characterized by high contents of carvacrol and thymol. Mentha pulegium was characterized by a high content of pulegone (74.8%) never put in evidence. The major components of Lavandula stoechas L. were fenchone (48.0%) and camphor (21.1%). Antibacterial activities against MRSA and MSSA were evaluated by disk diffusion method and microdilution broth assay. This is the first report on the antibacterial activity against MRSA for EOs from the species T. fontanesii and T. numidicus and for M. pulegium from Algeria. EOs were found to be strongly bactericidal (MIC from 0.3 μL/mL to 4.7 μL/mL) which suggests an additional option to treat MRSA infections.