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1.
Food Chem ; 307: 125521, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655264

RESUMO

The essential oils and antioxidant activity of four Thymus species were evaluated under five light spectra (namely, red, blue, red-blue, white, and greenhouse condition). The highest essential oil yield (4.17%) was observed under red light in T. migricus, while the lowest (1.05%) was observed in T. carmanicus under greenhouse conditions. Light quality also led to difference in essential oil constituents. The highest thymol (66%) was found in T. migricus exposed to blue light, while the least (1.69%) was observed in T. kotschyanus grown under red-blue light. The LED treatments did not induce any significant effect on carvacrol of Thymus species in comparison to the greenhouse condition. Finally, the analysis of variance indicates that the effect of light varied with the studied species. T. migricus performed the highest antioxidant capacity (IC50 = 176.8 µg/mL) under blue light. Overall, essential oil components as well as antioxidants showed significant responses to light emitting diodes wavelengths.


Assuntos
Antioxidantes/metabolismo , Luz , Timol/metabolismo , Thymus (Planta)/química , Análise de Variância , Antioxidantes/química , Cromatografia Gasosa , Análise por Conglomerados , Efeito Estufa , Óleos Voláteis/química , Análise de Componente Principal , Timol/química , Thymus (Planta)/crescimento & desenvolvimento , Thymus (Planta)/metabolismo
2.
IET Nanobiotechnol ; 13(2): 114-119, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31051440

RESUMO

Fluconazole (FLZ) application as a highly successful commercial antifungal azole agent to treat the fungal infections is limited due to emergence of FLZ-resistant candida. In this study, the potential of green synthesised silver nanoparticles (NPs) as an antifungal agent against Candida albicans fungal pathogen is investigated. The extract of ginger (Zingiber officinale) and thyme (Thymus vulgaris) plays as reducing agent, capping agent and antifungal agent. The UV-visible spectroscopy shows the peak of surface plasmon resonance of synthesised Ag NPs after a period of time. The synthesised Ag NPs are spherical, with average sizes of 12 and 18 nm based on ginger and thyme extract, respectively. Fourier transform infrared spectroscopy confirms the adsorption of the plant extract on the surface of the as-prepared Ag NPs. Based on the minimum inhibitory concentration (MIC) method against Candida albicans, the antifungal activity of as-prepared green synthesised Ag NPs shows higher inhibitory in comparison to FLZ. Finally, the Ag NPs synthesised via thyme extract shows no cytotoxicity with concentration below 3.5 ppm, which can be considered as an appropriate candidate instead of FLZ to treat the superficial fungal infections.


Assuntos
Antifúngicos/química , Gengibre/metabolismo , Nanopartículas Metálicas/química , Prata/química , Thymus (Planta)/metabolismo , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fluconazol/farmacologia , Química Verde , Humanos , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/química , Prata/metabolismo , Prata/farmacologia
3.
Food Chem ; 291: 199-206, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006459

RESUMO

The influence of homogenization conditions on selected essential oil (thyme, lemongrass, cinnamon, peppermint, and clove)-in-water nanoemulsion formation and stability was investigated. Physically stable essential oil nanoemulsions could be fabricated by a microfludizer under optimized processing conditions (10,000 psi and 2 passes). The chemical compositions of EOs was characterized using GC-MS. The antifungal activity and mycotoxin inhibitory activity of essential oils in both bulk and nanoemulsion forms were determined using two isolates of Fusarium graminearum. The major chemical components of essential oil had a remarkable impact on long term physical stability, antifungal activity, and inhibition of mycotoxin production. With regard to inhibition of mycotoxin production, the mycotoxin inhibitory activity of essential oils was enhanced considerably in nanoemulsion form, which was attributed to greater solubility of the essential oils. It was also noted that the same essential oils exhibited significant differences in inhibition of mycotoxin production in the two isolates of F. graminearum.


Assuntos
Antifúngicos/química , Emulsões/química , Óleos Voláteis/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cinnamomum zeylanicum/química , Cinnamomum zeylanicum/metabolismo , Cymbopogon/química , Cymbopogon/metabolismo , Fusarium/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Micotoxinas/análise , Micotoxinas/antagonistas & inibidores , Micotoxinas/metabolismo , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , Syzygium/química , Syzygium/metabolismo , Thymus (Planta)/química , Thymus (Planta)/metabolismo
4.
Food Chem ; 278: 415-423, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583392

RESUMO

During the last years, the food industry is working on the replacement of high energy methodologies with more sustainable techniques for the encapsulation of natural preservatives, in order to enhance their effectiveness as food additives. In the present study, nisin, an antimicrobial agent, was encapsulated in essential oil-containing microemulsions. More specifically, rosemary, thyme, oregano, and dittany essential oil-containing microemulsions were formulated to encapsulate nisin enhancing the system's overall antimicrobial activity. The systems were investigated for the interfacial properties and size of the surfactants' monolayer using electron paramagnetic resonance spectroscopy and dynamic light scattering. Subsequently, nisin-loaded microemulsions were tested for their antimicrobial activity against Lactococcus lactis, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus, using the well diffusion assay. Finally, this technique was validated by a killing assay. Overall, this study provides important information on the antibacterial activity of nisin-loaded nano-carriers enhanced by essential oils, in relation to the microemulsions' structure.


Assuntos
Anti-Infecciosos/química , Micelas , Nanoestruturas/química , Nisina/química , Óleos Voláteis/química , Anti-Infecciosos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Espectroscopia de Ressonância de Spin Eletrônica , Emulsões/química , Microbiologia de Alimentos , Lactococcus lactis/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Nisina/farmacologia , Origanum/química , Origanum/metabolismo , Rosmarinus/química , Rosmarinus/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Thymus (Planta)/química , Thymus (Planta)/metabolismo , Viscosidade
5.
Sci Rep ; 8(1): 14634, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30279427

RESUMO

Honey bees are highly prone to infectious diseases, causing colony losses in the worst case. However, they combat diseases through a combination of their innate immune system and social defence behaviours like foraging for health-enhancing plant products (e.g. nectar, pollen and resin). Plant secondary metabolites are not only highly active against bacteria and fungi, they might even enhance selective foraging and feeding decisions in the colony. Here, we tested six major plant terpenes and their corresponding acetates, characterizing six natural Thymus vulgaris chemotypes, for their antimicrobial activity on bacteria associated with European foulbrood. Comparison of the inhibitory activity revealed the highest activity for carvacrol and thymol whereas the acetates mostly did not inhibit bacterial growth. All terpenes and acetates are present in the nectar and pollen of thyme, with pollen containing concentrations higher by several orders of magnitude. The physiological response was tested on forager and freshly emerged bees by means of antennal electroantennography. Both responded much stronger to geraniol and trans-sabinene hydrate compared to carvacrol and thymol. In conclusion, bee-forageable thyme product terpenes (mainly from pollen) yield effective antibiotic activity by reducing the growth of bee disease-associated bacteria and can be detected with different response levels by the honey bees' antennae. This is a further step forward in understanding the complex pathogen-pollinator-plant network.


Assuntos
Abelhas/microbiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Monoterpenos/farmacologia , Thymus (Planta)/metabolismo , Animais , Folhas de Planta/química , Néctar de Plantas/química , Pólen/química
6.
Plant Physiol Biochem ; 132: 391-399, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30286404

RESUMO

Drought is one of the most important threats to plants and agriculture; therefore, understanding of the mechanism of drought tolerance is crucial for breeding of drought tolerant plants. Here, we assessed effects of four levels of drought (90%, 55%, 40% and 25% FC) on some physiological criteria and metabolite adjustment of two different drought-responsive thyme plants (Thymus vulgaris as drought sensitive and T. Kotschyanus as drought tolerant species), using 1H-NMR. Among three physiological parameters and 18 identified metabolites, species × treatment effects were significant (P ≤ 0.01) for leaf temperature, acetic acid, citric acid, fumaric acid, malic acid, succinic acid, fructose, sucrose and serine. RWC, chlorophyll and carotenoids content, glucose, alanine and choline were affected by simple effects of species and treatment. Correlation analysis revealed that there is a different correlation between physiological parameters and metabolites in both species. This analysis also revealed that, by ignoring the correlation between malic acid and succinic acid in T. vulgaris, there was no significant correlation between TCA intermediate in both species. According to results, sugars, amino acid and energy metabolism were affected by drought and, among them, TCA intermediates had more alternation in two studied species so, this cycle and its intermediates probably have more prominent role than other identified metabolites in the induction of drought tolerance.


Assuntos
Adaptação Fisiológica , Secas , Metaboloma , Estresse Fisiológico , Thymus (Planta)/metabolismo , Thymus (Planta)/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Redes e Vias Metabólicas/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Análise de Componente Principal , Espectroscopia de Prótons por Ressonância Magnética , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos , Açúcares/farmacologia , Thymus (Planta)/efeitos dos fármacos
7.
J Plant Physiol ; 230: 101-108, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30368030

RESUMO

Thymus vulgaris L. (Lamiaceae), a well-known aromatic medicinal herb, has many important essential constituents in its oil, including γ-terpinene, carvacrol, thymol, and p-cymene. Gibberellins comprise hundreds of components, which regulate several various growths and underlying developmental processes, such as cell division and elongation, shoot elongation, seed germination, and gene expression. In this study, we investigated the influence of sprayed gibberellic acid (GA3) treatments on the internode length, leaf morphology, length of new shoot, expression of monoterpene synthase genes and monoterpenes content during two plant growth stages. Our results showed that increasing of internode length was a clear effect of GA3 that was varied with internode position. The results also showed that all internodes displayed a dramatic increase in the highest concentration of GA3. Also, the foliar application of GA3 resulted in not only an increased expression level of monoterpene synthase genes, but also the improved production of a monoterpene, especially in the moderate concentration of GA3 that they were up-regulated. In the lowest GA3 concentrations, relative expression levels were similar or lower than the control plants and a notable downregulation in those genes was observed in the application of the highest concentration of GA3 rather than the moderate concentrations. Overall, the expression of two out of five monoterpene synthase genes, TPS and CYP71D181, showed a correlation with the level of γ-terpinene and carvacrol, respectively, indicating that they are regulated at the transcriptional levels.


Assuntos
Giberelinas/farmacologia , Liases Intramoleculares/genética , Reguladores de Crescimento de Planta/farmacologia , Thymus (Planta)/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Liases Intramoleculares/metabolismo , Thymus (Planta)/efeitos dos fármacos , Thymus (Planta)/enzimologia , Thymus (Planta)/genética , Regulação para Cima/efeitos dos fármacos
8.
Molecules ; 23(7)2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29932435

RESUMO

Thymus plants are marketed for diverse usages because of their pleasant odor, as well as high nutritional value and wealth of health-promoting phytochemicals. In this study, Thymuszygis, Thymuspulegioides, and Thymusfragrantissimus grown under organic cultivation regime were characterized regarding nutrients and phenolic compounds. In addition, the antioxidant and antibacterial properties of these species were screened. The plants were particularly notable for their high K/Na ratio, polyunsaturated fatty acids content and low omega-6/omega-3 fatty acids ratios, which are valuable features of a healthy diet. Caffeic acid and/or its derivatives, mainly rosmarinic acid and caffeoyl rosmarinic acid, represented the majority of the phenolic constituents of these plants, although they were less representative in T. pulegioides, which in turn was the richest in flavones. The latter species also exhibited the highest antioxidant capacity (DPPH● EC50 of 9.50 ± 1.98 µg/mL and reducing power EC50 of 30.73 ± 1.48 µg/mL), while T. zygis was the most active towards Gram-positive and Gram-negative bacteria. Overall, the results suggest that the three thyme plants grown in organic farming are endowed with valuable metabolites that give them high commercial value for applications in different industries.


Assuntos
Antibacterianos/química , Antioxidantes/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Thymus (Planta)/química , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Ácidos Cafeicos/química , Ácidos Cafeicos/isolamento & purificação , Cinamatos/química , Cinamatos/isolamento & purificação , Depsídeos/química , Depsídeos/isolamento & purificação , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/isolamento & purificação , Ácidos Graxos Ômega-6/química , Ácidos Graxos Ômega-6/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Fenóis/química , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Picratos/antagonistas & inibidores , Extratos Vegetais/farmacologia , Potássio/química , Potássio/isolamento & purificação , Sódio/química , Sódio/isolamento & purificação , Thymus (Planta)/metabolismo
9.
Molecules ; 23(4)2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29671816

RESUMO

Thymus quinquecostatus Celak is a species of thyme in China and it used as condiment and herbal medicine for a long time. To set up the quality evaluation of T. quinquecostatus, the response surface methodology (RSM) based on its 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was introduced to optimize the extraction condition, and the main indicator components were found through an UPLC-LTQ-Orbitrap MSn method. The ethanol concentration, solid-liquid ratio, and extraction time on optimum conditions were 42.32%, 1:17.51, and 1.8 h, respectively. 35 components having 12 phenolic acids and 23 flavonoids were unambiguously or tentatively identified both positive and negative modes to employ for the comprehensive analysis in the optimum anti-oxidative part. A simple, reliable, and sensitive HPLC method was performed for the multi-component quantitative analysis of T. quinquecostatus using six characteristic and principal phenolic acids and flavonoids as reference compounds. Furthermore, the chemometrics methods (principal components analysis (PCA) and hierarchical clustering analysis (HCA)) appraised the growing areas and harvest time of this herb closely relative to the quality-controlled. This study provided full-scale qualitative and quantitative information for the quality evaluation of T. quinquecostatus, which would be a valuable reference for further study and development of this herb and related laid the foundation of further study on its pharmacological efficacy.


Assuntos
Plantas Medicinais/metabolismo , Thymus (Planta)/metabolismo , Cromatografia Líquida de Alta Pressão , Estresse Oxidativo , Plantas Medicinais/química , Análise de Componente Principal , Thymus (Planta)/química
10.
Plant Physiol Biochem ; 123: 65-74, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29223848

RESUMO

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.


Assuntos
Flavonoides/biossíntese , Depuradores de Radicais Livres/metabolismo , Óleos Voláteis/metabolismo , Folhas de Planta/metabolismo , Ácido Salicílico/farmacologia , Thymus (Planta)/metabolismo
11.
J Plant Physiol ; 218: 35-44, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28763707

RESUMO

The essential oil of Thymus albicans Hoffmanns. & Link, a native shrub from the Iberian Peninsula, is mainly composed of monoterpenes. In this study, a 1,8-cineole synthase was isolated from the 1,8-cineole chemotype. A partial sequence that lacked the complete plastid transit peptide but contained an extended C-terminal when compared to other related terpene synthases was generated by PCR and Rapid Amplification of cDNA Ends (RACE). The predicted mature polypeptide was 593 amino acids in length and shared 78% and 77% sequence similarity with the homologue 1,8-cineole synthase from Rosmarinus officinalis and Salvia officinalis, respectively. The putative protein possessed the characteristic conserved motifs of plant monoterpene synthases including the RRx8W and DDxxD motifs and phylogenetic analysis indicated that the amplified 1,8-cineole synthase bears greater sequence similarity with other 1,8-cineole synthases from Lamiaceae family relative to the terpene synthases from the genus Thymus. Functional expression of the recombinant protein in Escherichia coli revealed that in the presence of geranyl diphosphate (GPP) 1,8-cineole was the major product but that its production was too low for robust quantification. Other minor conversion products included α-pinene, ß-pinene, sabinene and ß-myrcene suggesting the isolated 1,8-cineole synthase may be a multi-product enzyme. To our knowledge, this is the first report of a functionally characterized monoterpene synthase from Thymus albicans.


Assuntos
Evolução Molecular , Liases Intramoleculares/genética , Proteínas de Plantas/genética , Thymus (Planta)/genética , Sequência de Aminoácidos , Escherichia coli/genética , Liases Intramoleculares/química , Liases Intramoleculares/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Thymus (Planta)/metabolismo
12.
J Agric Food Chem ; 65(32): 6821-6830, 2017 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-28722406

RESUMO

Phytogenic feed additives represent a potential alternative to antibiotics with attributed health and growth-promoting effects. Chickens supplemented with an essential oil blend, a Quillaja saponin blend, or a combination of both phytogenic preparations showed a comprehensively and significantly improved apparent ileal digestibility of crude protein and amino acids compared to control birds. Accordingly, holistic transcriptomic analyses of jejunum and liver samples indicated alterations of macromolecule transporters and processing pathways likely culminating in an increased uptake and metabolizing of carbohydrates and fatty acids. Complementary analyses in Caco-2 showed a significant increase in transporter recruitment to the membrane (SGLT1 and PEPT1) after addition of essential oils and saponins. Although the penetrance of effects differed for the used phytogenic feed additives, the results indicate for an overlapping mode of action including local effects at the intestinal border and systemic alterations of macronutrient metabolism resulting in an improved performance of broilers.


Assuntos
Ração Animal/análise , Galinhas/metabolismo , Aditivos Alimentares/metabolismo , Íleo/metabolismo , Illicium/química , Óleos Voláteis/metabolismo , Origanum/metabolismo , Rosmarinus/metabolismo , Saponinas/metabolismo , Thymus (Planta)/metabolismo , Animais , Células CACO-2 , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Digestão , Humanos , Óleos Voláteis/análise , Origanum/química , Proteínas/genética , Proteínas/metabolismo , Rosmarinus/química , Saponinas/análise , Thymus (Planta)/química
13.
Plant Physiol Biochem ; 115: 152-162, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28365519

RESUMO

Thyme (Thymus vulgaris L.) is known to produce a variety of phenolic monoterpenes such as thymol and carvacrol. Thymol and carvacrol are health-promoting, biocide and antitoxin compounds and have been considered as the main constituents of essential oils in T. vulgaris. To improve our understanding of the regulation of monoterpene biosynthesis in thyme, the expression of genes related to thymol and carvacrol biosynthesis in different tissues and in response to abiotic elicitors was analyzed. Methyl jasmonate (MeJA), salicylic acid (SA), trans-cinnamic acid (tCA) and UV-C irradiation were applied to T. vulgare leaves and transcript levels of early (DXR) and late (TvTPS1, CYP71D178 and CYP71D180) biosynthetic genes of thymol and carvacrol were measured. The results showed that early step and late step genes in thymol/carvacrol biosynthesis are differentially regulated. DXR was not found to be exclusively expressed in glandular trichomes; in contrast, biosynthetic genes including γ-terpinene synthase (TvTPS1) and two cytochrome P450s, CYP71D178 and CYP71D180, were preferentially expressed in glandular secretory trichomes. The high expression of late biosynthetic genes in glandular trichomes, which also contain the highest concentration of thymol and carvacrol, suggests that glandular trichomes are the structure in which thymol/carvacrol biosynthesis and accumulation occur. Our results indicate that in addition to abiotic elicitors, developmental and spatial factors also play a key role in the biosynthesis of thymol and carvacrol, most likely relating to glandular trichome density and/or activity. Hence optimization of these factors could be considered as a useful strategy to achieve high yield of valuable compounds in T. vulgare or other closely related plant species.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Monoterpenos/metabolismo , Timol/metabolismo , Thymus (Planta)/metabolismo , Flores/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Estrutura Molecular , Monoterpenos/química , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Timol/química , Transcriptoma , Tricomas/fisiologia
14.
Anal Biochem ; 527: 49-62, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28209457

RESUMO

Thyme as a perennial herb has been recognized globally for its antimicrobial, antiseptic and spasmolytic effects. In this investigation, we have used non-targeted metabolite and volatile profiling combined with the morpho-physiological parameters in order to understand the responses at the metabolite and physiological level in drought sensitive and tolerant thyme plant populations. The results at the metabolic level identified the significantly affected metabolites. Significant metabolites belonging to different chemical classes consisting amino acids, carbohydrates, organic acids and lipids have been compared in tolerant and sensitive plants. These compounds may take a role through mechanisms including osmotic adjustment, ROS scavenging, cellular components protection and membrane lipid changes, hormone inductions in which the key metabolites were proline, betain, mannitol, sorbitol, ascorbate, jasmonate, unsaturated fatty acids and tocopherol. Regarding with volatile profiling, sensitive plants showed an increased-then-decreased trend at major terpenes apart from alpha-cubebene and germacrene-D. In contrast, tolerant populations had unchanged terpenes during the water stress period with an elevation at last day. These results suggesting that the two populations are employing different strategies. The combination of metabolite profiling and physiological parameters assisted to understand precisely the mechanisms of plant response at volatile metabolome level.


Assuntos
Adaptação Fisiológica , Secas , Metaboloma , Folhas de Planta/metabolismo , Thymus (Planta)/metabolismo , Aminoácidos/biossíntese , Aminoácidos/isolamento & purificação , Carboidratos/biossíntese , Carboidratos/isolamento & purificação , Ácidos Carboxílicos/isolamento & purificação , Ácidos Carboxílicos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Lipídeos/biossíntese , Lipídeos/isolamento & purificação , Metabolômica , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Análise de Componente Principal , Estresse Fisiológico , Terpenos/isolamento & purificação , Terpenos/metabolismo , Thymus (Planta)/química , Thymus (Planta)/crescimento & desenvolvimento
15.
Chem Biodivers ; 14(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27685426

RESUMO

Thymus munbyanus subsp. coloratus (Lamiaceae) is a small shrub endemic to Algeria and Morocco where is found in lawns, rockeries and mountainous regions. From a phytochemical point of view this taxon has never been characterized. In this work we have analysed the chemical compositions of the essential oils obtained from inflorescences and vegetative parts by GC/MS. A new chemotype, i.e. borneol-chemotype, was characterized for the first time in the species. Furthermore, we assessed the biological activities of essential oils, namely the antioxidant, antimicrobial and cytotoxicity on tumor cells that were evaluated by the DPPH, ABTS, and FRAP, disc diffusion, and MTT methods, respectively. Biological assays highlighted a moderate inhibitory effect on Staphylococcus aureus, Escherichia coli and Candida albicans (inhibition zone diameter in the range 9 - 10 mm), and noteworthy cytotoxicity on A375 human melanoma cells (IC50 of 46.95 µg/ml).


Assuntos
Antineoplásicos Fitogênicos/química , Lamiaceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Thymus (Planta)/química , Argélia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Candida albicans/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Lamiaceae/metabolismo , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Thymus (Planta)/metabolismo
16.
Int J Food Microbiol ; 240: 40-46, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27590560

RESUMO

Consumers' demand for ready-to-eat (RTE) turkey meat is attributed to its convenience and healthy properties. However, as cooked meat product it is subjected to post-process contamination, thus allowing presence and growth of microbial pathogens, such as Salmonella spp.. The aim of this study was to include a natural antimicrobial, thyme essential oil (TEO), on RTE turkey products in order to evaluate its effectiveness throughout the shelf life. To do so, the effect of four different formulations of cooked RTE turkey products on Salmonella Enteritidis behaviour was investigated. Products' slices were surface inoculated with S. Enteritidis (ca. 4 to 5logcfu/g), subsequently stored at 10 and 25°C and microbiologically analysed during 18 and 12days, respectively. Predictive microbiology models fitted to count data were used to evaluate microbial behaviour. Results showed that S. Enteritidis behaviour on RTE turkey products slices during storage was strongly dependent on temperature. The pathogen was able to grow on slices at all tested conditions during storage at 25°C and no statistical differences were detected (p>0.05) between growth parameters. At 10°C, different behaviour patterns were observed. The application of TEO led to higher Salmonella inactivation rates on a product exempt of chemical preservatives. The addition of this novel antimicrobial on meat products or its incorporation on meat active packaging systems as a part of hurdle technology could increase RTE turkey products safety while satisfying the demand of more natural foods.


Assuntos
Antibacterianos/farmacologia , Contaminação de Alimentos/prevenção & controle , Conservantes de Alimentos/farmacologia , Armazenamento de Alimentos/métodos , Listeria monocytogenes/crescimento & desenvolvimento , Produtos da Carne/microbiologia , Óleos Voláteis/farmacologia , Salmonella enteritidis/crescimento & desenvolvimento , Thymus (Planta)/metabolismo , Animais , Temperatura Baixa , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Culinária , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Carne/microbiologia , Salmonella enteritidis/efeitos dos fármacos , Perus
17.
Oxid Med Cell Longev ; 2016: 1458793, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27774115

RESUMO

High blood pressure is the most powerful contributor to the cardiovascular morbidity and mortality, and inverse correlation between consumption of polyphenol-rich foods or beverages and incidence of cardiovascular diseases gains more importance. Reactive oxygen species plays an important role in the development of hypertension. We found that wild thyme (a spice plant, rich in polyphenolic compounds) induced a significant decrease of blood pressure and vascular resistance in hypertensive rats. The inverse correlation between vascular resistance and plasma heme oxygenase-1 suggests that endogenous vasodilator carbon monoxide generated by heme oxidation could account for this normalization of blood pressure. Next product of heme oxidation, bilirubin (a chain-breaking antioxidant that acts as a lipid peroxyl radical scavenger), becomes significantly increased after wild thyme treatment and induces the reduction of plasma lipid peroxidation in hypertensive, but not in normotensive rats. The obtained results promote wild thyme as useful supplement for cardiovascular interventions.


Assuntos
Heme Oxigenase-1/sangue , Hipertensão/prevenção & controle , Thymus (Planta)/química , Animais , Antioxidantes/química , Bilirrubina/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Catalase/metabolismo , Ensaio de Imunoadsorção Enzimática , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Glutationa Peroxidase/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Heme Oxigenase-1/análise , Hemodinâmica/efeitos dos fármacos , Hipertensão/metabolismo , Rim/enzimologia , Rim/metabolismo , Fígado/enzimologia , Fígado/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Endogâmicos SHR , Superóxido Dismutase/metabolismo , Thymus (Planta)/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
Food Chem ; 212: 503-11, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27374561

RESUMO

The aim of this study was to improve the oxidative stability of soybean oil by using aromatic plants. Soybean oil flavored with rosemary (ROS) and soybean oil flavored with thyme (THY) were subjected to heating for 24h at 180°C. The samples were analyzed every 6h for their total polar compounds, anisidine values, oxidative stability and polyphenols content. The tocopherols content was determined and volatile compounds were also analyzed. After 24h of heating, the incorporation of these plants using a maceration process reduced the polar compounds by 69% and 71% respectively, in ROS and THY compared to the control. Until 6h of heating, the ROS kept the greatest oxidative stability. The use of the two extracts preserves approximately 50% of the total tocopherols content until 18h for the rosemary and 24h for the thyme flavored oils. Volatile compounds known for their antioxidant activity were also detected in the formulated oils. Aromatic plants added to the soybean oil improved the overall acceptability of potato crisps (p<0.05) until the fifteenth frying.


Assuntos
Calefação/efeitos adversos , Rosmarinus/metabolismo , Óleo de Soja/metabolismo , Thymus (Planta)/metabolismo , Antioxidantes/análise , Antioxidantes/metabolismo , Aromatizantes/análise , Aromatizantes/metabolismo , Humanos , Oxirredução , Folhas de Planta/metabolismo , Óleo de Soja/análise , Paladar , Tunísia
19.
Acta Biol Hung ; 67(1): 64-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26960357

RESUMO

A pot experiment was carried out with lemon balm (Melissa officinalis L.) and thyme (Thymus vulgaris L.). Different water supply was applied: 25%, 40% and 70% saturation of soil water capacity (SWC). Morphological traits, biomass and phenolic type active ingredients were investigated. Among the two species, main differences were registered in biomass and TPC. Lower SWC resulted in reduced biomass production of lemon balm, while the applied stress treatments did not effect the biomass of thyme. In lemon balm, highest TPC contents were measured in control plants both in shoots and roots but in thyme, the shoots showed a significantly increased TPC at the 25% SWC conditions. Neither the content of total flavonoids nor that of the rosmarinic acid was affected by the treatments. The antioxidant capacity proved to be in tight connection with the TPC in both species (r = 0.766-0.883). The rosmarinic acid content of lemon balm plants contributed to the antioxidant capacity, as well (r = 0.679-0.869).


Assuntos
Cinamatos/metabolismo , Depsídeos/metabolismo , Flavonoides/metabolismo , Melissa/metabolismo , Polifenóis/metabolismo , Thymus (Planta)/metabolismo , Antioxidantes/metabolismo , Biomassa , Melissa/crescimento & desenvolvimento , Thymus (Planta)/crescimento & desenvolvimento
20.
Int J Food Microbiol ; 215: 95-100, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26350124

RESUMO

There is a growing interest in the use of naturally-occurring antimicrobial agents such as plant essential oils (EOs) to inhibit the growth of hazardous and spoilage microorganisms in foods. Gaseous EOs (EO gases) have many potential applications in the food industry, including use as antimicrobial agents in food packaging materials and sanitizing agents for foods and food-contact surfaces, and in food processing environments. Despite the potentially beneficial applications of EO gases, there is no standard method to evaluate their antimicrobial activities. Thus, the present study was aimed at developing an experimental apparatus and protocol to determine the minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) of EO gases against microorganisms. A sealed experimental apparatus was constructed for simultaneous evaluation of antimicrobial activities of EO gases at different concentrations without creating concentration gradients. A differential medium was then evaluated in which a color change allowed for the determination of growth of glucose-fermenting microorganisms. Lastly, an experimental protocol for the assessment of MIC and MLC values of EO gases was developed, and these values were determined for 31 EO gases against Escherichia coli O157:H7 as a model bacterium. Results showed that cinnamon bark EO gas had the lowest MIC (0.0391 µl/ml), followed by thyme-thymol EO gas (0.0781 µl/ml), oregano EO gas (0.3125 µl/ml), peppermint EO gas (0.6250 µl/ml), and thyme-linalool EO gas (0.6250 µl/ml). The order of the MLC values of the EO gases against the E. coli O157:H7 was thyme-thymol (0.0781 µl/ml)

Assuntos
Anti-Infecciosos/farmacologia , Escherichia coli O157/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Manipulação de Alimentos , Microbiologia de Alimentos , Embalagem de Alimentos , Mentha piperita/metabolismo , Testes de Sensibilidade Microbiana , Monoterpenos/farmacologia , Óleos Voláteis/metabolismo , Origanum/metabolismo , Timol/farmacologia , Thymus (Planta)/metabolismo
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