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1.
Food Chem ; 371: 131111, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543928

RESUMO

Thyme (Thymus vulgaris L.) is widely used as a traditional spice in the cooking of goat meat (mutton) due to its distinctive flavor and the ability to weaken the "goaty flavor". To investigate the aroma characteristics of stewed mutton with thyme (SMT), four SMT samples prepared using different cooking utensils were analyzed by gas chromatography-mass spectrometry/olfactometry (GC-MS/O). Totally, 26 aroma-active compounds (AACs) were determined by GC-MS/O and further quantified. Among these, 20 AACs exhibited odor activity values (OAV) greater than 1. However, no significant differences existed among the four SMTs, which indicated that different utensils had little effect on the aroma profile of SMTs. Aroma recombination and omission experiments results showed that nonanal, (E)-2-octenal, and (E,E)-2,4-decadienal had the greatest contribution to the aroma profile of SMTs. These three compounds, together with dimethyl trisulfide, 3-methyl-butanal, octanal, (E)-2-decenal, (E)-2-nonenal, methanethiol, hexanal, (E)-2-undecenal, and 1-octen-3-ol, were confirmed as the key aroma compounds in SMTs.


Assuntos
Thymus (Planta) , Compostos Orgânicos Voláteis , Animais , Cabras , Carne , Odorantes , Olfatometria
2.
Sci Total Environ ; 807(Pt 1): 150716, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34626636

RESUMO

Among the numerous studies devoted to the photodegradation of pesticides, very scarce are those investigating the effect of plant volatiles. Yet, pesticides can be in contact with plant volatiles after having been spread on crops or when they are transported in surface water, making interactions between the two kinds of chemicals possible. The objectives of the present study were to investigate the reactions occurring on plants. We selected thyme as a plant because it is used in green roofs and two pesticides: the fungicide chlorothalonil for its very oxidant excited state and the insecticide imidacloprid for its ability to release the radical NO2 under irradiation. Pesticides were irradiated with simulated solar light first in a solvent ensuring a high solubility of pesticides and plant volatiles, and then directly on thyme's leaves. Analyses were conducted by headspace gas chromatography-mass spectrometry (HS-GC-MS), GC-MS and liquid chromatography-high resolution mass spectrometry (LC-HRMS). In acetonitrile, chlorothalonil photosensitized the degradation of thymol, α-pinene, 3-carene and linalool with high quantum yields ranging from 0.35 to 0.04, and was photoreduced, while thymol underwent oxidation, chlorination and dimerization. On thyme's leave, chlorothalonil was photoreduced again and products arising from oxidation and dimerization of thymol were detected. Imidacloprid photooxidized and photonitrated thymol in acetonitrile, converting it into chemicals of particular concern. Some of these chemicals were also found when imidacloprid was irradiated dispersed on thyme's leaves. These results show that photochemical reactions between pesticides and the plants secondary metabolites can take place in solution as on plants. These findings demonstrate the importance to increase our knowledge on these complex scenarios that concern all the environmental compartments.


Assuntos
Praguicidas , Thymus (Planta) , Cromatografia Gasosa-Espectrometria de Massas , Praguicidas/análise , Plantas , Timol
3.
Meat Sci ; 184: 108697, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34687928

RESUMO

The aim of this research was to determine the effect of pectin coating made with essential oils and/or extracts of Thymus vulgaris (thyme) and Thymbra spicata (thymbra) on the preservation of aerobically packaged sliced bolognas during cold storage. The treatment made with essential oils resulted in a reduction of 1.73 log CFU/g of Salmonella typhimurium ATCC 14028. Also, pectin coating made with essential oil-treated sliced bolognas had the lowest total mesophilic bacteria (6.27 log CFU/g), and total lactic acid bacteria (1.72 CFU/g), in comparison to non-treated bolognas, with 7.65 log CFU/g for total mesophilic bacteria and 4.99 log CFU/g for lactic acid bacteria. Application of an emulsion significantly (P < 0.05) affected L*(lightness), a*(redness), and b*(yellowness) values. The essential oil treatment had the highest TBARS values at the end of the storage period. The pH was not affected by the treatment (P > 0.05), but storage had a significant (P < 0.05) effect on the pH values.


Assuntos
Filmes Comestíveis , Produtos da Carne/microbiologia , Óleos Voláteis , Pectinas , Cor , Microbiologia de Alimentos , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Lactobacillales/crescimento & desenvolvimento , Lamiaceae/química , Salmonella typhimurium/crescimento & desenvolvimento , Thymus (Planta)/química
5.
Molecules ; 26(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34641393

RESUMO

This study reported the volatile profile, the antimicrobial activity and the synergistic potential of essential oil (EO) from the Moroccan endemic Thymus atlanticus (Ball) Roussine, in combination with the antibiotics ciprofloxacin and fluconazole for the first time, to the best of our knowledge. The EO chemical composition was determined by gas chromatography coupled to mass spectrometry (GC-MS) analysis and the antimicrobial activity assessed by the disc diffusion method against three Gram positive (Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus) and three Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and one clinical isolate, Klebsiella pneumonia). The antifungal activity was evaluated in four pathogenic yeasts (Candida albicans, C. glabrata, C. krusei and C. parapsilosis). The minimum inhibition concentration (MIC) and the synergistic effect with ciprofloxacin and fluconazole were determined by the two-fold dilution technique and checkerboard test, respectively. Twenty-one constituents were identified by GC-MS in the EO, including carvacrol (21.62%) and borneol (21.13%) as the major components. The EO exhibited a significant antimicrobial activity with inhibition zones ranging from 0.7 mm to 22 mm for P. aeruginosa and B. subtilis, respectively, and MIC values varying from 0.56 mg/mL to 4.47 mg/mL. The fractional inhibitory concentration index (FICI) values ranged from 0.25 to 0.50 for bacteria and from 0.25 to 0.28 for yeasts. The maximum synergistic effect was observed for K. pneumonia with a 256-fold gain of antibiotic MIC. Our results have suggested that EO from T. atlanticus may be used alone or in association with antibiotics as a new potential alternative to prevent and control the emergence of resistant microbial strains both in the medical field and in the food industry.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Óleos Voláteis/farmacologia , Thymus (Planta)/química , Marrocos
6.
Braz J Biol ; 83: e244675, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34586190

RESUMO

Several species of thymus have therapeutic properties, so they are used in traditional medicine. In this work was carried out to synthesize Thymus vulgalis silver nanoparticles (TSNPS) and evaluate antioxidant and antimicrobial activities of TSNPS and T. vulgalis essential oil extract (TEOE). The essential oils analyzed by GC-MS and were characterized. Major compounds of phenol, 2 methyl 5 (1 methylethyle) (CAS), thymol and 1,2 Benzene dicarboxylic acid, 3 nitro (CAS) (48.75%, 32.42% and 8.12%, respectively) were detected. Results demonstrated that the TSNPS gave a highest DPPH radical scavenging activity, it was obtained 97.2 at 1000 ug/ml. TSNPS, Thymus + Hexane (T+H), Thymus + Ethanol (T+E) gave the greatest antimicrobial activity than amoxicillin (AM) and ciprofloxacin (CIP). In conclusion: The essential oil of thymus (Vulgaris) and thymus (Vulgaris) silver nanoparticles can be a good source of natural preservatives as an antioxidant and antimicrobial agents for increasing the shelf life of foodstuffs.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Óleos Voláteis , Thymus (Planta) , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Óleos Voláteis/farmacologia , Prata
7.
Ann Agric Environ Med ; 28(3): 414-418, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34558263

RESUMO

INTRODUCTION: Fusaria are microscopic filamentous fungi which are spread in soil, in various organic substrates, and include more than 80 phytopathogenic species which are predominantly hosted by cereals, fruits and vegetables. Many of these species, under certain conditions, are capable of synthesizing secondary metabolites, mycotoxins. At present, various substances are used for their elimination and one of the solutions appears to be essential oils. In the presented study, the antifungal activity of essential oils was researched in vitro. MATERIAL AND METHODS: In this study, two standard fungal isolates Fusarium graminearum CCM F-683 and Fusarium graminearum CCM 8244 (Brno, Czech Republic) were used. The antifungal effect of 6 tested essential oils (Syzygium aromaticum, Origanum vulgare, Thymus vulgaris, Hyssopus officinalis , Ocimum basilicum, Myristica fragrans) was determined using the broth microdilution method, which allows reading of the MIC (minimum inhibitory concentration). According to the results obtained, the growth inhibition of Fusarium graminearum was determined by assay for the inhibition of radial growth of the mycelium. RESULTS: The inhibitory effects of thymus, oregano, basil, myristica, hyssop and syzygium essential oil (EO) on mycelial growth of Fusarium graminearum CCM F-683 and CCM 8244 were investigated. The best antifungal activity against the both strains of Fusarium graminearum (37.4%; 40.7%) was demonstrated by Origanum vulgare EO at the concentration 100 µg/mL. Among the four tested oils, three (Syzygium aromaticum, Thymus vulgaris, Origanum vulgare) achieved the best inhibitory effect (100%) at concentrations 500 µg/mL and 1000 µg/mL. CONCLUSIONS: In the protection of plants against pathogenic fungi, essential oils appear to be a suitable substitute for synthetic chemicals.


Assuntos
Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Fusarium/crescimento & desenvolvimento , Hyssopus/química , Testes de Sensibilidade Microbiana , Myristica/química , Ocimum basilicum/química , Origanum/química , Syzygium/química , Thymus (Planta)/química
8.
Molecules ; 26(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34577079

RESUMO

Antimicrobial resistance is a dramatic global threat; however, the slow progress of new antibiotic development has impeded the identification of viable alternative strategies. Natural antioxidant-based antibacterial approaches may provide potent therapeutic abilities to effectively block resistance microbes' pathways. While essential oils (EOs) have been reported as antimicrobial agents, its application is still limited ascribed to its low solubility and stability characters; additionally, the related biomolecular mechanisms are not fully understood. Hence, the study aimed to develop a nano-gel natural preparation with multiple molecular mechanisms that could combat bacterial resistance in an acne vulgaris model. A nano-emulgel of thyme/clove EOs (NEG8) was designed, standardized, and its antimicrobial activity was screened in vitro and in vivo against genetically identified skin bacterial clinical isolates (Pseudomonas stutzeri, Enterococcus faecium and Bacillus thuringiensis). As per our findings, NEG8 exhibited bacteriostatic and potent biofilm inhibition activities. An in vivo model was also established using the commercially available therapeutic, adapalene in contra genetically identified microorganism. Improvement in rat behavior was reported for the first time and NEG8 abated the dermal contents/protein expression of IGF-1, TGF-ß/collagen, Wnt/ß-catenin, JAK2/STAT-3, NE, 5-HT, and the inflammatory markers; p(Ser536) NF-κBp65, TLR-2, and IL-6. Moreover, the level of dopamine, protective anti-inflammatory cytokine, IL-10 and PPAR-γ protein were enhanced, also the skin histological structures were improved. Thus, NEG8 could be a future potential topical clinical alternate to synthetic agents, with dual merit mechanism as bacteriostatic antibiotic action and non-antibiotic microbial pathway inhibitor.


Assuntos
Acne Vulgar/tratamento farmacológico , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Comportamento Animal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polietilenoglicóis/farmacologia , Polietilenoimina/farmacologia , Pele/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Biofilmes/efeitos dos fármacos , Sinais (Psicologia) , Fatores de Transcrição Forkhead/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Nanogéis/química , Nanogéis/uso terapêutico , PPAR gama/metabolismo , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Polietilenoglicóis/química , Polietilenoglicóis/uso terapêutico , Polietilenoimina/química , Polietilenoimina/uso terapêutico , Ratos , Pele/metabolismo , Syzygium/química , Thymus (Planta)/química , Receptor 2 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas Wnt/metabolismo
9.
Curr Med Res Opin ; 37(10): 1837-1844, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34340607

RESUMO

OBJECTIVE: Efficacy and safety of an oral thyme/ivy syrup for the treatment of acute cough was previously demonstrated in a randomized clinical trial. Here, we present real-life data from a pharmacy-based, observational study on the effectiveness and tolerability of another thyme/ivy combination (BNO 1200, Bronchipret drops). METHODS: This observational, prospective, uncontrolled study was conducted in 305 German pharmacies. Cough and associated symptoms, cough severity and health related quality of life (HRQoL) were assessed at baseline, after 4 days and at individual end of treatment (EoT) in patients with acute cough due to upper respiratory tract infections who bought BNO 1200. Patients took BNO 1200 until resolution of cough and completed three validated questionnaires: patient-adapted Bronchitis Severity Score (BSS), cough severity visual analogue scale (VAS) and the Leicester Cough Questionnaire (LCQ-acute). They also rated speed of onset of treatment action on a VAS and tolerability. RESULTS: A total of 749 patients participated in the study; 730 were included in the analysis. Mean treatment duration was 7.0 ± 3.6 days. Symptom severity assessed by BSS improved from 8.7 ± 3.8 score points (baseline) to 2.4 ± 2.6 at EoT (p < .0001). Clinically relevant improvements (MCID = 17 mm) in cough severity were reported by 87.2% of patients at EoT. HRQoL improved significantly (12.2 ± 3.3 points at baseline vs. 18.5 ± 2.7 at EoT; p < .0001), exceeding the MCID (=2 points) in 90.0% of patients. Tolerability was rated "good" or "very good" by 98.0% of patients. No adverse drug reactions were reported. CONCLUSION: Patients with acute cough taking BNO 1200 had a significant reduction in BSS, cough severity and improvement in HRQoL confirming RCT data with the syrup formulation. BNO 1200 was well tolerated.


Assuntos
Farmácias , Farmácia , Thymus (Planta) , Tosse/tratamento farmacológico , Humanos , Extratos Vegetais , Estudos Prospectivos , Qualidade de Vida
10.
Phytomedicine ; 91: 153673, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34416627

RESUMO

BACKGROUND: Thymus quinquecostatus Celak. has been widely used as a spice and a folk medicine for relieving exterior syndrome and alleviating pain in China. PURPOSE: To explore the protective effects and the underlying mechanism against cerebral ischemia-reperfusion injury (CIRI) of the T. quinquecostatus combining with its chemical composition. STUDY DESIGN AND METHODS: High-polar extract (HPE) was extracted from T. quinquecostatus and polyphenols in HPE were enriched to obtain polyphenol-rich fraction (PRF) using Macroporous resin. The free radicals and zebrafish embryos were used to compare the antioxidant activities of HPE and PRF in vitro and in vivo. Then, the transient middle cerebral artery occlusion (tMCAO) model was established in rats. Neurological deficit score, infarction rate, morphology and apoptosis of neurons were examined to investigate the protective effects of PRF on CIRI. The mRNA and protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1) and the activities of downstream antioxidant enzymes in ischemia tissues were determined to clarify the underlying mechanisms. Also, reactive oxygen species (ROS) level in zebrafish embryos were detected after incubation with PRF for a short time (2 h) to investigate whether PRF could directly eliminate free radicals. Finally, chemical composition of PRF were analyzed to investigate the material basis for antioxidant activity and anti-CIRI effect. RESULTS: Compared with HPE, PRF showed stronger antioxidant activities. PRF exhibited obvious protective effects including ameliorating neurological deficit, lowering infarction rate, and improving the cellular morphology in hippocampus CA1 and cortex after tMCAO. TUNEL staining suggested PRF dose-dependently improved the apoptosis of the neurons in ischemic cortex. RT-qPCR and Western Blot results suggested that PRF regulated oxidative stress (OS) via activating the Keap1/Nrf2/HO-1 signaling pathway. Also, PRF could directly scavenge excessive ROS in zebrafish embryos after a short-time PRF incubation. The anti-CIRI effect might be primarily attributed to the abundant polyphenols in PRF, including flavonoids, polymethoxylated flavonoids, flavonoid glycosides, and phenolic acids. CONCLUSION: T. quinquecostatus contains abundant polyphenols and exhibited a good protective effect against CIRI via dual antioxidant mechanisms, providing a reference for further research and application for this plant.


Assuntos
Antioxidantes , Isquemia Encefálica , Extratos Vegetais/farmacologia , Traumatismo por Reperfusão , Thymus (Planta)/química , Animais , Antioxidantes/farmacologia , Isquemia Encefálica/tratamento farmacológico , Heme Oxigenase-1/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais , Peixe-Zebra/metabolismo
11.
Molecules ; 26(16)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34443525

RESUMO

The epidemiology of yeast infections and resistance to available antifungal drugs are rapidly increasing, and non-albicans Candida species and rare yeast species are increasingly emerging as major opportunistic pathogens. In order to identify new strategies to counter the threat of antimicrobial resistant microorganisms, essential oils (EOs) have become an important potential in the treatment of fungal infections. EOs and their bioactive pure compounds have been found to exhibit a wide range of remarkable biological activities. We investigated the in vitro antifungal activity of nine commercial EOs such as Thymus vulgaris (thyme red), Origanum vulgare (oregano), Lavandula vera (lavender), Pinus sylvestris (pine), Foeniculum vulgare (fennel), Melissa officinalis (lemon balm), Salvia officinalis (sage), Eugenia caryophyllata (clove) and Pelargonium asperum (geranium), and some of their main components (α-pinene, carvacrol, citronellal, eugenol, γ-terpinene, linalool, linalylacetate, terpinen-4-ol, thymol) against non-albicans Candida strains and uncommon yeasts. The EOs were analyzed by GC-MS, and their antifungal properties were evaluated by minimum inhibitory concentration and minimum fungicidal concentration parameters, in accordance with CLSI guidelines, with some modifications for EOs. Pine exhibited strong antifungal activity against the selected non-albicans Candida isolates and uncommon yeasts. In addition, lemon balm EOs and α-pinene exhibited strong antifungal activity against the selected non-albicans Candida yeasts. Thymol inhibited the growth of all uncommon yeasts. These data showed a promising potential application of EOs as natural adjuvant for management of infections by emerging non-albicans Candida species and uncommon pathogenic yeasts.


Assuntos
Antifúngicos/química , Candida/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Antifúngicos/farmacologia , Candida/patogenicidade , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Farmacorresistência Fúngica/efeitos dos fármacos , Foeniculum/química , Humanos , Lavandula/química , Melissa/química , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Origanum/química , Pinus sylvestris/química , Óleos Vegetais/química , Salvia officinalis/química , Syzygium/química , Thymus (Planta)/química
12.
Molecules ; 26(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443694

RESUMO

Thymus vulgaris L. is one of the most commonly used medicinal and aromatic plants (MAPs), owing to a range of therapeutic properties of its essential oil. Plant growth, biomass yield, essential oil content and composition are influenced by chemotype, environmental conditions, cultivation techniques and vegetative development. Since in MAPs cultivation special attention is paid on high quality of raw material, the adoption of sustainable agriculture methods is of pivotal importance. Therefore, we evaluated the agronomic and qualitative performances of two Thymus vulgaris L. chemotypes, organically cultivated under the Mediterranean climate of hilly lands of central Italy for three consecutive years (2017-2019). Along the trial, total above-ground dry biomass significantly increased from the 1st to 3rd year after planting and large variations in the main biological, biometric and productive traits were observed between the two chemotypes. The 'thymol' chemotype EO obviously showed thymol as the major constituent (51.26-49.87%) followed by γ-terpinene and p-cymene. The 'linalool' chemotype EO showed high percentages of oxygenated monoterpenes (about 90%) with linalool (75%), linalyl acetate (8.15%) and b-caryophyllene (3.2%) as main constituents. This study highlighted that T. vulgaris can be successfully organically grown in the hilly lands of Tuscany, with interesting biomass and essential oil yields, even though the plants were in the initial years of crop establishment (start in 2017). The introduction of this species into organic cultivation systems could contribute to obtain high-quality raw material, as well as to enhance crop rotation diversification, which is of pivotal importance in the management of organic farms.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Óleos Voláteis/análise , Thymus (Planta)/química , Destilação , Itália , Análise de Componente Principal , Chuva , Estações do Ano , Solo/química
13.
Molecules ; 26(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203164

RESUMO

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drugs in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration and heat-, ultrasound-, and microwave-assisted extractions. Higher total powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher total powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation was distinguished from the others by a higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process mainly affected the position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray-dried formulations compared to freeze-dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and a higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder.


Assuntos
Gelatina/química , Extratos Vegetais/química , Thymus (Planta)/química , Liofilização , Secagem por Atomização
14.
Int J Biol Macromol ; 185: 535-542, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34216656

RESUMO

Antimicrobial films based on polylactic acid (PLA) were developed by incorporating Thymus vulgaris essential oil (TV-EOs) with different concentrations of ethanolic extract of Mediterranean propolis (EEP) (5 wt% and 10 wt% based on PLA). The antimicrobial activities of EEP were performed by the agar disc diffusion method. The EEP exhibited high antimicrobial properties with inhibition zone diameter of 12.1 and 11.58 mm against Staphylococcus aureus and Penicillium sp., respectively. The addition of TV-EOs to films containing 5 and 10 wt% of EEP decrease the elastic modulus from 1292 MPa to 1084 MPa and 911.1 MPa to 794 MPa compared with films containing 5 and 10% of EEP alone, respectively. However, the elongation at break increased by 64% after the addition of TV-EOs to the film containing 10 wt% of EEP. Thermal stability of films improvement by the addition of TV-EOs and EEP. Antimicrobial activity of the films showed that films containing 10 wt% EEP inhibited the growth of Candida albicans and the combination of EEP and TV-EOs in the PLA matrix showed a synergistic effect against Escherichia coli. The developed PLA-based films with antimicrobial activity have a potential application in food packaging to increase the shelf life of packaged food.


Assuntos
Antibacterianos/farmacologia , Etanol/farmacologia , Óleos Voláteis/farmacologia , Poliésteres/química , Própole/química , Thymus (Planta)/química , Antibacterianos/química , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Etanol/química , Embalagem de Alimentos , Armazenamento de Alimentos , Óleos Voláteis/química , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Sci Rep ; 11(1): 15279, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315968

RESUMO

Intercropping of medicinal plants/legumes along with bio-fertilizer application is a relatively new sustainable practice for improving the yield and secondary metabolites production. Here, a 2-years field experiment was performed to evaluate the effects of water deficit stress and arbuscular mycorrhizal fungi (AMF) application (as bio-fertilizer) on nutrients concentration, dry matter yield, essential oil quantity and quality of thyme in intercropping with soybean. Three irrigation levels, including (i) irrigation after depletion of 20% (I20) as non-stressed, 50% (I50) as moderate water deficit and 80% (I80) available water as severe water deficit were applied as the main factor. The sub-factor was represented by different cropping patterns including thyme sole culture, replacement intercrop ratio of 50:50 and 66:34 (soybean: thyme) and the third factor was non-usage (control) and usage of AMF. According to our results, the thyme dry yield under moderate and severe water deficit stress decreased by 35 and 44% in the first year, and by 27 and 40% in the second year compared with non-stressed (I20) plants, respectively. Also, the macro- and micro-nutrients of thyme leaves increased significantly in intercropping patterns after application of AMF. The maximum essential oil percentage of thyme was achieved in 50:50 intercropping ratio treated with AMF. Under moderate and severe water deficits, the major constituents of thyme essential oil including thymol, p-cymene and γ-terpinene were increased in intercropping patterns treated with AMF. Generally, AMF application in intercropping ratio of 50:50 may be proposed to farmers as an eco-friendly approach to achieve desirable essential oil quality and quantity in thyme under water deficit stress conditions.


Assuntos
Produtos Agrícolas , Desidratação/metabolismo , Fungos/fisiologia , Soja/metabolismo , Thymus (Planta)/metabolismo , Óleos Voláteis/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/microbiologia , Soja/crescimento & desenvolvimento , Soja/microbiologia , Thymus (Planta)/crescimento & desenvolvimento
16.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199618

RESUMO

This study determined the antimicrobial and antioxidant activity of lemongrass (LO), thyme (TO), and oregano (OO) essential oils and ethanolic extracts of pomegranate peel (PPE) and grape pomace (GPE) as candidate ingredients for edible coatings. Antifungal effects against Botrytis cinerea and Penicillium spp. were tested using paper disc and well diffusion methods. Radical scavenging activity (RSA) was evaluated using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid assays. Gas chromatography-mass spectrometry analysis identified limonene (16.59%), α-citral (27.45%), ß-citral (27.43%), thymol (33.31%), paracymene (43.26%), 1,8-cineole (17.53%), and trans-caryphellene (60.84%) as major compounds of the essential oils. From both paper disc and well diffusion methods, LO recorded the widest zone of inhibition against tested microbes (B. cinerea and Penicillium spp.). The minimum inhibitory concentrations of LO against B. cinerea and Penicillium spp., were 15 µL/mL and 30 µL/mL, respectively. The highest (69.95%) and lowest (1.64%) RSA at 1 mg/mL were recorded for PPE and OO. Application of sodium alginate and chitosan-based coatings formulated with LO (15 or 30 µL/mL) completely inhibited spore germination and reduced the decay severity of 'Wonderful' pomegranate. Lemongrass oil proved to be a potential antifungal agent for edible coatings developed to extend shelf life of 'Wonderful' pomegranate.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Cymbopogon/química , Óleos Voláteis/farmacologia , Origanum/química , Thymus (Planta)/química , Anti-Infecciosos/química , Antioxidantes/química , Botrytis/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Penicillium/efeitos dos fármacos , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Esporos Fúngicos/efeitos dos fármacos , Terpenos
17.
Molecules ; 26(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200464

RESUMO

Due to lifespan extension and changes in global climate, the increase in mycoses caused by primary and opportunistic fungal pathogens is now a global concern. Despite increasing attention, limited options are available for the treatment of systematic and invasive mycoses, owing to the evolutionary similarity between humans and fungi. Although plants produce a diversity of chemicals to protect themselves from pathogens, the molecular targets and modes of action of these plant-derived chemicals have not been well characterized. Using a reverse genetics approach, the present study revealed that thymol, a monoterpene alcohol from Thymus vulgaris L., (Lamiaceae), exhibits antifungal activity against Cryptococcus neoformans by regulating multiple signaling pathways including calcineurin, unfolded protein response, and HOG (high-osmolarity glycerol) MAPK (mitogen-activated protein kinase) pathways. Thymol treatment reduced the intracellular concentration of Ca2+ by controlling the expression levels of calcium transporter genes in a calcineurin-dependent manner. We demonstrated that thymol decreased N-glycosylation by regulating the expression levels of genes involved in glycan-mediated post-translational modifications. Furthermore, thymol treatment reduced endogenous ergosterol content by decreasing the expression of ergosterol biosynthesis genes in a HOG MAPK pathway-dependent manner. Collectively, this study sheds light on the antifungal mechanisms of thymol against C. neoformans.


Assuntos
Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Cryptococcus neoformans/efeitos dos fármacos , Timol/farmacologia , Calcineurina/metabolismo , Criptococose/metabolismo , Cryptococcus neoformans/metabolismo , Ergosterol/farmacologia , Proteínas Fúngicas/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monoterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Thymus (Planta)/química
18.
Molecules ; 26(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34279395

RESUMO

The use of natural compounds with biocidal activity to fight the growth of bacteria responsible for foodborne illness is one of the main research challenges in the food sector. This study reports the preparation and physicochemical characterization of chitosan nanoparticles loaded with Thymus capitatus (Th-CNPs) and Origanum vulgare (Or-CNPs) essential oils. The nanosystems were obtained by ionotropic gelation technique with high encapsulation efficiency (80-83%) and loading capacity (26-27%). Nanoparticles showed a spherical shape, bimodal particle size distribution, and good stability (zeta potential values > 40 mV). The treatment of the nanosuspensions at different temperatures (4 and 40 °C) and storage times (7, 15, 21, and 30 days) did not affect their physicochemical parameters and highlights their reservoir ability for essential oils also under stressful conditions. Both Or-CNPs and Th-CNPs exhibited an enhanced bactericidal activity against foodborne pathogens (S. aureus, E. coli, L. monocytogenes) than pure essential oils. These ecofriendly nanosystems could represent a valid alternative to synthetic preservatives and be of interest for health and food safety.


Assuntos
Anti-Infecciosos/farmacologia , Nanopartículas/química , Óleos Voláteis/farmacologia , Origanum/química , Óleos Vegetais/farmacologia , Thymus (Planta)/química , Anti-Infecciosos/administração & dosagem , Quitosana/química , Listeria monocytogenes/efeitos dos fármacos , Óleos Voláteis/administração & dosagem , Óleos Vegetais/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos
19.
Molecules ; 26(12)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204728

RESUMO

This study aimed at an experimental design of response surface methodology (RSM) in the optimization of the dominant volatile fraction of Greek thyme honey using solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). For this purpose, a multiple response optimization was employed using desirability functions, which demand a search for optimal conditions for a set of responses simultaneously. A test set of eighty thyme honey samples were analyzed under the optimum conditions for validation of the proposed model. The optimized combination of isolation conditions was the temperature (60 °C), equilibration time (15 min), extraction time (30 min), magnetic stirrer speed (700 rpm), sample volume (6 mL), water: honey ratio (1:3 v/w) with total desirability over 0.50. It was found that the magnetic stirrer speed, which has not been evaluated before, had a positive effect, especially in combination with other factors. The above-developed methodology proved to be effective in the optimization of isolation of specific volatile compounds from a difficult matrix, like honey. This study could be a good basis for the development of novel RSM for other monofloral honey samples.


Assuntos
Mel/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Grécia , Thymus (Planta)/metabolismo
20.
J Food Prot ; 84(10): 1809-1818, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115849

RESUMO

ABSTRACT: The application of plant extracts (PEs) could be a promising option to satisfy consumers' demand for natural additives to inhibit growth of variable pathogenic bacteria. Thus, the aim of this study was to develop a standardized microdilution method to examine the antimicrobial effects of 10 hydrophilic PEs against two strains of Clostridium perfringens facing various food-relevant influencing factors. Because of the high opacity of PEs, resazurin was used as an indicator for bacterial growth instead of pellet formation. The highest value of the MIC of the replications of each PE was defined as effective plant extract concentration (EPC), whereas the next concentration beneath the lowest MIC was defined as the ineffective plant extract concentration (IEPC). The EPCs of seven PEs, allspice, cardamom, cinnamon, clove, coriander, ginger, and mace, were between 0.625 and 10 g/kg, whereas extracts of caraway, nutmeg, and thyme showed no antimicrobial activity up to the maximum concentration tested (10 g/kg) against C. perfringens in vitro. Two intrinsic factors, sodium chloride (NaCl) and sodium nitrite (NaNO2), displayed either synergistic or additive effects or no interaction with most PEs. By combination with PEs at their IEPC (0.08 to 1.25 g/kg), MIC of NaCl and NaNO2 decreased from between 25 and 50 g/kg to between 6 and 25 g/kg and from more than 200 mg/kg to between 0.2 and 100 mg/kg, respectively. In contrast, lipid (sunflower oil) at a low concentration inhibited the antimicrobial effects of all tested PEs. For extrinsic factors, only allspice, ginger, and coriander could maintain their antimicrobial effects after being heated to 78°C for 30 min. The synergistic effect between PEs and pH values (5.0 and 5.5) was also found for all PEs. The established screening method with resazurin and defining EPC and IEPC values allows the verification of antimicrobial effects of PEs under various food-relevant influencing factors in a fast and reproducible way.


Assuntos
Anti-Infecciosos , Thymus (Planta) , Antibacterianos/farmacologia , Clostridium perfringens , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
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