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1.
Food Chem ; 333: 127433, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659662

RESUMO

This study examined the effects of exogenous citrulline (control, 1 and 2 mM) and water availability (100%, 50% and 25% WA) on antioxidant attributes and essential oil constituents of Hyssopus officinalis L. in two successive harvests. Hyssop tolerantly responded to water deficiency by well-promoted antioxidant enzymes (i.e., superoxide dismutase, and catalase), strong DPPH-scavenging activity, and increasing polyphenols; however, the essential oil content was negatively reduced by water stress. External citrulline further increased the activity of antioxidant enzymes. Citrulline application at 2 mM under severe water stress could also improve essential oil (EO) content in the first and second harvests by about 15 and 30%, respectively. Furthermore, under severe drought, citrulline at 2 mM could obtain the highest yield of isopinocamphone (47%) as the main component of EO. The results showed the high potential of this novel applied metabolite agent to be used in a well-fulfilled production of this medicinal plant.


Assuntos
Antioxidantes/metabolismo , Citrulina/farmacologia , Hyssopus/efeitos dos fármacos , Hyssopus/fisiologia , Óleos Voláteis/metabolismo , Canfanos/metabolismo , Catalase/metabolismo , Catecol Oxidase/metabolismo , Desidratação , Secas , Hyssopus/química , Óleos Voláteis/análise , Proteínas de Plantas/metabolismo , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/fisiologia , Polifenóis/metabolismo , Superóxido Dismutase/metabolismo
2.
PLoS One ; 15(6): e0234688, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559255

RESUMO

There have been recent advances in predicting odor characteristics using molecular structure parameters of chemicals. Although the molecular structure parameters are available for each chemical, they cannot be used for chemical mixtures. This study will elucidate a computational method of predicting human odor perception from the mass spectra of chemical mixtures such as essential oils. Furthermore, a method for obtaining similarity among odor descriptors has been proposed although the dataset contains binary values only. When the database indicates a set of odor descriptors for one sample, only binary data are available and the correlation between the similar descriptors disappears. Thus, the prediction performance degrades for not considering the similarity among the odor descriptors. Since mass spectra dataset is highly dimensional, we use auto-encoder to learn the compressed representation from the mass spectra of essential oils in its bottleneck hidden layer and then accomplishes the hierarchical clustering to create odor descriptor groups with similar odor impressions using a matrix of continuous value-based correlation coefficient as well as natural language processing. This work will help to expatiate the process of overcoming binary value problem and find out the similarity among odor descriptors using machine learning with natural language semantic representation of words. To overcome the problem of disproportionate ratio of positive and negative class for both the continuous value-based correlation coefficient and word similarity based models, we use Synthetic Minority Oversampling Technique (SMOTE). This model allows us to predict human odor perception through computer simulations by forming odor descriptors group. Accordingly, this study demonstrates the feasibility of ensembling machine learning with natural language processing and SMOTE approach for predicting odor descriptor group from mass spectra of essential oils.


Assuntos
Espectrometria de Massas , Odorantes/análise , Óleos Voláteis/análise , Olfato/fisiologia , Análise por Conglomerados , Humanos , Modelos Teóricos , Estatística como Assunto
3.
Food Chem ; 331: 127278, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32569965

RESUMO

1H quantitative Nuclear Magnetic Resonance (qNMR) spectroscopy technique has certain advantages such as low-temperature operation, authentic structural prediction and short data acquisition time. In this study, a 1H qNMR method was developed for the analysis of propenylbenzenes (eugenol and seven analogues) in the essential oils, a broadly distributed class of natural flavours. It was validated in terms of specificity (methoxy/acetate signal), linearity (range 0.05-5.00 mg per assay), sensitivity (limit of detection and quantification 4.4 and 14.9 µg/mL respectively), accuracy and precision. The qNMR technique was utilized during the sensory or activity-guided identification of chavibetol as the key odorant and antioxidant in the betel (Piper betle L., Bangla cultivar) oil, a widely consumed chewing stimulant and valuable flavouring agent. The method was also applied for the evaluation of six different post-harvest drying techniques for betel leaves through the quantitative analysis of unambiguously identified propenylbenzene markers (chavibetol, chavibetol acetate and 4-allyl-1,2-phenylene diacetate).


Assuntos
Antioxidantes/análise , Odorantes/análise , Óleos Voláteis/análise , Piper betle/química , Espectroscopia de Prótons por Ressonância Magnética/métodos , Benzeno/análise , Benzeno/química , Dessecação , Eugenol/análogos & derivados , Eugenol/análise , Humanos , Limite de Detecção , Micro-Ondas , Óleos Voláteis/química , Folhas de Planta/química , Reprodutibilidade dos Testes
4.
J Oleo Sci ; 69(6): 643-648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32493886

RESUMO

Sour citrus are prized for their flavor and fragrance. This work identified the components of the peel oil of Hetsuka-daidai (Citrus sp. hetsukadaidai), a special sour citrus that is native to the southern part of the Osumi peninsula, Kagoshima, Japan. These compounds were compared to those identified from the peels of six other major sour citrus: lime (Citrus latifolia), lemon (Citrus limon), Yuzu (Citrus junos), Kabusu (Citrus aurantium), Kabosu (Citrus sphaerocarpa), and Sudachi (Citrus sudachi). Peel oil contents were analyzed for the duration of four months during harvest season to investigate the differences in peel oil/fragrance during ripening. These results could facilitate the development of preferred flavor and scent profiles using local species.


Assuntos
Citrus/química , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Estações do Ano , Cromatografia Gasosa-Espectrometria de Massas , Japão , Óleos Voláteis/análise
5.
J Chromatogr A ; 1621: 461084, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32303345

RESUMO

This work presents a new triptycene-based dicationic guanidinium ionic liquid (TPG) as the stationary phase for gas chromatography (GC). To our knowledge, this is the first example of employing a dicationic guanidinium ionic liquid (GIL) for chromatographic analyses. As a result, the TPG column exhibited moderate polarity and column efficiency of 3840 plates/m and 3120 plates/m measured by naphthalene and 1-octanol at 120 °C, respectively. Particularly, the TPG column exhibited distinctly advantageous performance for the challenging Grob test mixture and the isomer mixture of phenols and anilines over the monocationic GIL and its counterpart with dicationic immidazolium units (TP-2IL). Also, it showed higher selectivity towards the isomers of alkanes, alcohols, diethylbenzenes, bromotoluenes, bromonitrobenzenes than the commercial DB-35MS column. Moreover, the TPG column achieved improved thermal stability over the GIL column and excellent repeatability with the RSD values of 0.01-0.05% for run-to-run, 0.11-0.24% for day-to-day and 2.4-4.1% for column-to-column. Its application to GC-MS analysis of the essential oil of Mentha haplocalyx proved its good potential for analysis of complex samples.


Assuntos
Antracenos/química , Guanidina/química , Líquidos Iônicos/química , Alcanos/química , Compostos de Anilina/química , Cromatografia Gasosa-Espectrometria de Massas , Líquidos Iônicos/análise , Isomerismo , Mentha/química , Óleos Voláteis/análise , Fenóis/química , Reprodutibilidade dos Testes , Solventes , Temperatura
6.
Int J Nanomedicine ; 15: 795-807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32103937

RESUMO

Background and Study: Cumin seed oil (extracted from Cuminum cyminum) has many applications but conclusive evidence of its therapeutic uses has not been presented. This study has explored the anticancer and antibacterial properties of the seed oil. Methods: The cumin nanoemulsion was prepared with Tween 80 non-ionic surfactant employing ultra-sonication technology. The anticancer activity of the nanoscale-based emulsion was evaluated through cell viability (MTT), antiproliferation evaluation through clonogenic assay, and apoptosis through Annexin V-FITC assay. Agar well diffusion was used to study the antimicrobial activity, and this was supported by membrane integrity analysis. Results: A thorough study of process parameters, aimed at obtaining the optimal surface concentration and emulsification time, was completed. GC-MS data indicated cumaldehyde as a major component. The resultant droplet diameter after a sonication time of 5 min was 10.4 ± 0.5 nm. MTT assay revealed the IC50 value at 1.5 µL/mL and the early induction of apoptosis was evident. Tongue carcinoma cell line treated with cumin nanoemulsion presented a diminished colony formation. The nanoemulsion exhibited significant antibacterial activity against S. aureus. A significant cytoplasmic leakage was observed on treatment with cumin nanoemulsion. The consequences of the analysis projected cumin as a potential component for cancer therapy. Conclusion: This study provides definitive evidence for cumin essential oil nanoemulsion as a legitimate plant-based medicine that can bypass the drawbacks of the present aggressive treatment of cancer, can overcome the antimicrobial resistance, and can also meet all prerequisites.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cuminum/química , Emulsões/química , Nanoestruturas/química , Óleos Voláteis/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Óleos Voláteis/análise , Óleos Voláteis/química , Sementes/química , Staphylococcus aureus/efeitos dos fármacos , Ultrassom
7.
J Chromatogr A ; 1619: 460969, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32089290

RESUMO

Room temperature ionic liquids (ILs) are well established stationary phases (SPs) for gas chromatography (GC) in several fields of applications because of their unique and tunable selectivity, low vapor pressure and volatility, high thermal stability (over 300 °C), and good chromatographic properties. This study is focused on an IL based on a phosphonium derivative (trihexyl(tetradecyl)phosphonium chloride, [P66614+] [Cl-]), previously shown to be suitable as a gas chromatographic SP because of its unique selectivity. In particular, it aims to establish the operative conditions to apply [P66614+][Cl-] to routine analysis of samples containing medium to high volatility analytes with different polarity, organic functional groups and chemical structure. In the first part, the study critically evaluates long term [P66614+][Cl-] column stability and maximum allowable operating temperatures (MAOT). The relatively low MAOT (210 °C) requires the adoption of a dedicated approach for analytes eluting above this temperature based on a suitable combination of efficiency and selectivity, and column characteristics (length, inner diameter and film thickness) and operative conditions. The performance of [P66614+][Cl-] as a GC SP have been validated through the Grob test, a model mixture of 41 compounds of different polarity, structure, and with different organic functional groups in the flavor and fragrance field, a standard mixture of 37 fatty acid methyl esters, some essential oils containing pairs or groups of compounds of different volatility critical to separate in particular peppermint, thyme, oregano, sandalwood and frankincense. The above approach has produced highly satisfactory separations with all of the samples investigated.


Assuntos
Cromatografia Gasosa/métodos , Líquidos Iônicos/química , Compostos Organofosforados/química , Aromatizantes/análise , Odorantes/análise , Óleos Voláteis/análise , Perfumes/análise , Santalum , Sesquiterpenos/análise , Temperatura
8.
J Chem Ecol ; 46(2): 163-175, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32026207

RESUMO

The adaptive radiation of the angiosperms was strongly affected by fruit and seed dispersal since the establishment of the seedlings is a fundamental process for the recruitment of juveniles to the populations. Among the species of Burseraceae, seeds with fleshy attachments and high caloric value suggest mammaliochory as an ancestral dispersal way. In Protium icicariba, at the same time as there is a visual pattern typical of ornithochory, with a report of effective demonstration, the diaspores present the highest levels of essential oils of the whole plant, suggesting other dispersion processes by olfactory guided vectors. This work aims to monitor the diasporic dispersal process in P. icicariba in situ, aiming to identify dispersers and to investigate the role of the essential oil in the dispersion of diaspores of this plant species. The natural dispersion was monitored in situ, in weekly campaigns throughout eight months, using visual and photographic records, in daily shifts of six hours, distributed along the dawn, morning, afternoon, dusk, and night. We used both direct observation and continuous picture capturing along 43 days with photographic traps. Mature diaspores removed from pseudocapsules were pooled to determine potential dispersers. Artificial models of the diaspores, in white and green colors, were also used to test hypotheses on the role of scent in the dispersion, added 1%, weight/weight, of the essential oil extracted from the mature diaspores, which chemical composition determined by gas chromatography coupled to mass spectrometry. Besides, the analysis of stomach contents of lizards collected in adjacent area was also performed. In daytime and nighttime monitoring in nature, no vertebrates were recorded dispersing diaspores. The most common was the primary wind-facilitated autochory of diaspores to the substrate, near the plant matrices. Secondarily, workers of the ant species Atta robusta can remove the pseudoarils or move the pyrenes to the anthills. The lizard species Tropidurus torquatus ingests pyrenes with the pseudoarils, and the sclerified pericarp of the pyrene is potentially resistant to chemical action of the digestive juices. Ants and lizards have also accessed the caves with natural diaspores. Concerning the artificial diaspore models, ants accessed, indistinctly, white and the green models that contained essential oils. The lizards accessed the white models, with or without essential oils, and showed insignificant access to green ones, with or without essential oil. The ingestion of pyrenes by lizards was also confirmed through analysis of stomach contents. The aggregate spatial pattern of P. icicariba at the study site, associated with clumps, may be derived from germination in the substrate near the matrices, or in the anthills or after diaspora defecation and / or regurgitation of the lizard, which is a species strongly associated with clumps of this vegetation. As the access to the diaspores by ants and lizards depends on the primary autochory, and no impediments to the germination near to the matrix plant were found, the dispersion is compatible with a multifactorial characteristic of the diplochory.


Assuntos
Burseraceae/metabolismo , Dispersão de Sementes , Animais , Formigas/fisiologia , Burseraceae/química , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Lagartos/metabolismo , Modelos Teóricos , Óleos Voláteis/análise , Óleos Voláteis/química , Óleos Vegetais/análise , Óleos Vegetais/química , Estômago/química
9.
Anal Bioanal Chem ; 412(7): 1535-1549, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31915868

RESUMO

Vladimiriae Radix, a geo-authentic medicinal herb found in Sichuan Province in China, is highly similar in chemical composition and pharmacological activity to Aucklandiae Radix. It is often used in local practice and as a substitute for Aucklandiae Radix in the treatment of gastrointestinal tract diseases. However, Vladimiriae Radix is preferred to Aucklandiae Radix in traditional Chinese medicine in Sichuan. In order to compare the difference in quality between the two species and differentiate them according to their chemical profiles, and further to explain the rationality of using Vladimiriae Radix as a substitute and explore the reason for the medication preference in Sichuan, similarity was evaluated using gas chromatography-mass spectrometry (GC-MS) fingerprinting and chemometric analysis. Volatile compounds were identified by comparing mass spectra with spectral data from the National Institute of Standards and Technology library 14.L (NIST 14.L) and the linear retention indices (RI) with those previously reported. The results showed that the similarity between the samples from Aucklandiae Radix (>96%) was greater than that of Vladimiriae Radix (>80%). In addition, 41 and 38 compounds were identified in 10 batches of Vladimiriae Radix and Aucklandiae Radix, respectively, and 21 compounds were common to both species, of which dehydrocostus lactone and aplotaxene were abundant in both. However, γ-patchoulene, longicyclene, ß-gurjunene, humulene1,2-epoxide, and ß-patchoulene were unique to Vladimiriae Radix, while 4-terpineol, α-ionone, trans-α-bergamotene, γ-selinene, and camphene were characteristic compounds of Aucklandiae Radix. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) suggested that the two species were well differentiated with regard to the level of essential oils. Orthogonal partial least squares discriminant analysis (OPLS-DA) further showed that compounds including costol, aplotaxene, caryophyllene, humulene, and ß-eudesmol, together with the characteristic compounds of the two species, could be regarded as potential markers for differentiation, among which ß-eudesmol, which is richer in Vladimiriae Radix, and ß-patchoulene, which is unique to Vladimiriae Radix, have potential therapeutic effects on gastrointestinal diseases. The results obtained in this study distinguished Vladimiriae Radix and Aucklandiae Radix on a chemical level, and the similarity in chemical constituents may provide a basis for the rationality of Vladimiriae Radix as a substitute, while ß-patchoulene and ß-eudesmol existing in Vladimiriae Radix provide a theoretical basis for its preferential use in Sichuan. The analysis method established here has important implications for the quality control and differentiation of Vladimiriae Radix and Aucklandiae Radix, which can also serve as a reference for the identification of similar species. Graphical abstract.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Raízes de Plantas/química , Medicina Tradicional Chinesa , Óleos Voláteis/análise , Plantas Medicinais/química , Controle de Qualidade , Reprodutibilidade dos Testes , Especificidade da Espécie
10.
Chem Biodivers ; 17(1): e1900496, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31909551

RESUMO

The genus Lavandula is known for its different uses in traditional medicine. This study is interested in the chemical composition of Lavandulapedunculata subsp.atlantica (Braun-Blanq.) Romo as well as evaluating its antibacterial potential against multi-resistant strains. The analysis of Lavandulaatlantica essential oil (LAEO) allows the identification of 47 components representing 93.6 % of all identified. The main constituent of LAEO was camphor (50.4 %), followed by fenchone (14.1 %) and camphene (5.6 %). The antibacterial assays revealed that LAEO was active against all the studied bacteria. A preliminary study of the relationship between certain terpenoids and antibacterial activity was also carried out in order to note the compound(s) that are responsible for LAEO's antibacterial activity. This study showed that the activity of the essential oil may be due to the presence of certain minor compounds such as carvone, considering the presence of the synergistic effect between the essential oil.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Lavandula/química , Óleos Voláteis/farmacologia , Terpenos/farmacologia , Antibacterianos/análise , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Relação Estrutura-Atividade , Terpenos/análise
11.
PLoS One ; 15(1): e0227235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31910241

RESUMO

Schizonepetae Spica (SS), the dried spike of Schizonepeta tenuifolia Briq., is a traditional Chinese medicinal herb. According to the color of persistent calyx, SS is categorized into two classes: the yellowish-green-type and the brownish-type. Based on the chemometrics analysis of gas chromatography-mass spectrometry (GC-MS), a novel model of identifying and evaluating the quality of SS in different colors was constructed for the first time in this work. 20 batches SS samples of different colors were collected and used to extract essential oils. The average essential oils yield of SS in yellowish-green color was significantly higher than that of SS in brownish color from the same origin (p<0.05). The GC-MS fingerprints of 20 batches SS samples whose correlation coefficients were over 0.964 demonstrated SS samples were consistent to some extent in spite of slightly different chemical indexes. A total of 39 common volatiles compounds were identified. Hierarchical clustering analysis (HCA), principal component analysis (PCA) and partial least-squares discriminate analysis (PLS-DA) were developed to distinguish SS samples characterized by different colors. Consistent results were obtained to show that SS samples could be successfully grouped according to their color. Finally, 4,5,6,7-tetrahydro-3,6-dimethyl-benzofuran and pulegone were detected as the key variables for discriminating SS samples of different colors and for quality control. The obtained results proved that SS of good quality were often yellowish-green and those of poor quality were often brownish.


Assuntos
Medicamentos de Ervas Chinesas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lamiaceae/química , Controle de Qualidade , Cor , Análise Discriminante , Medicamentos de Ervas Chinesas/normas , Óleos Voláteis/análise , Óleos Voláteis/isolamento & purificação , Componentes Aéreos da Planta/química , Análise de Componente Principal
12.
Chem Biodivers ; 17(2): e1900656, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31910318

RESUMO

The Cunila angustifolia essential oil was obtained from fresh leaves by hydrodistillation and analyzed by GC-FID and GC-MS to determine its chemical composition. The essential oil presented pulegone (29.5 %) and isomenthol (27.0 %) as major components, and other compounds such as menthone (8.6 %), neomenthol (7.2 %), menthyl acetate (2.5 %) and caryophyllene oxide (2.0 %) were identified. The cytotoxic activity of the essential oil was evaluated by MTS assay, with the human cancer cell lines of the lung (A549), breast (MCF-7) and skin melanoma (SK-Mel-28). The assay showed the highest selectivity, to MCF-7 cell lines, with IC50 equal to 34.0 µg mL-1 , low selectivity for SK-Mel-28 cell lines, with IC50 equal to 279.9 µg mL-1 , and no mortality to A549 cell lines.


Assuntos
Lamiaceae/química , Óleos Voláteis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lamiaceae/metabolismo , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo
13.
Chem Biodivers ; 17(2): e1900580, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31913571

RESUMO

Developing effective and eco-friendly antimicrobials and pesticides has become a highly important issue. The repellent, insecticidal and antimicrobial activity of essential oils (EOs) isolated by hydrodistillation from dried leaves of the three Eucalyptus species (E. cloeziana, E. umbellata and E. benthamii) were investigated. During GC/MS analysis, α-pinene (47.36 %), 1,8-cineol (38.53 %) and α-pinene (35.31 %) were identified as major components of E. cloeziana, E. umbellata and E. benthamii, respectively. The EOs from E. cloeziana exhibited the longest effective protection time (465 min, at 50.0 % w/w) for humans among the EOs studied. The effective protection time was 30 min and 300 min at concentrations of 12.5 % (w/w) and 25.0 % (w/w), respectively. Fumigating insecticidal activity of EOs from three Eucalyptus species was tested by airtight fumigation in conical flask, which indicated that essential oils had a highly and rapidly insecticidal activity on Culex pipiens quinquefasciatus. The antimicrobial activity of EOs was evaluated by using disc diffusion and agar dilution methods. There was no significant difference in the antibacterial activity of EOs from E. cloeziana and E. umbellate and they had the same MICs (20 mL/L) on Staphylococcus aureus, Salmonella typhi, Bacillus subtilis and Escherichia coli. E. benthamii had the worst microbial inhibitory effect among the three Eucalyptus essential oils and the MIC value for the test species is 40 mL/L except for Rhodotorula Harrison (10 mL/L).


Assuntos
Anti-Infecciosos/química , Eucalyptus/química , Repelentes de Insetos/química , Inseticidas/química , Óleos Voláteis/química , Folhas de Planta/metabolismo , Animais , Anti-Infecciosos/farmacologia , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Culex/efeitos dos fármacos , Eucalyptus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Folhas de Planta/química
14.
Molecules ; 25(2)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963829

RESUMO

There is significant research showing that essential oils extracted from the plants have antibacterial effects. The purpose of this study was to develop a biocomposite based on hydroxyapatite coated with Artemisia absinthium essential oil and to highlight its antibacterial activity. Therefore, present studies are aimed at developing new materials combining hydroxyapatite with Artemisia absinthium essential oil, in order to avoid postoperative infections. The purpose of this work is to highlight the antimicrobial properties of the Artemisia absinthium essential oil-hydroxyapatite composites obtained by a simple method and at low costs. The structural properties and antimicrobial efficiency of the Artemisia absinthium essential oil-hydroxyapatite composite have been studied. The samples based on Artemisia absinthium essential oil analyzed in this study showed that wormwood essential oil presented the highest efficacy against the fungal strain of C. parapsilosis. It has been shown that wormwood essential oil has a strong antimicrobial effect against the microbial strains tested in this study. Furthermore, the antimicrobial properties of the biocomposites based on hydroxyapatite and essential oil are due to the presence of the essential oil in the samples.


Assuntos
Artemisia absinthium/química , Durapatita/química , Difusão Dinâmica da Luz , Nanopartículas/química , Nanopartículas/ultraestrutura , Óleos Voláteis/análise , Raízes de Plantas/química
15.
Artigo em Inglês | MEDLINE | ID: mdl-31644378

RESUMO

The increased risk to health by diverse pathologies, such as cancer, liver diseases, and endocrine alterations, caused by chemical residues in food, has led to the search for sustainable agricultural management alternatives, such as the use of essential oils for the development of natural and eco-friendly fungicides. The aim of this study was to evaluate the antifungal and antiaflatoxigenic activity of Rosmarinus officinalis L. essential oil (REO) against Aspergillus flavus Link. REO was obtained by hydrodistillation and its major components were identified as 1,8-cineole (eucalyptol, 52.2%), camphor (15.2%) and α-pinene (12.4%) by GC/MS and NMR. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were both 500 µg/mL. REO reduced the mycelial growth of A. flavus at a concentration of 250 µg/mL (15.3%). The results obtained from scanning electron microscopy (SEM) demonstrated a reduction in the size of conidiophores and in the thickness of hyphae in A. flavus caused by treatment with REO (250 µg/mL). The production of ergosterol and the biomass of mycelium were both reduced as the REO treatment concentration increased. The production of aflatoxins B1 and B2 was inhibited after treatment with 250 µg/mL REO, a concentration below the MIC/MFC, indicating that the antiaflatoxigenic effect of REO is independent of its antifungal effect and is likely due to its direct action upon toxin biosynthesis. The data demonstrated that REO may be used as an alternative to synthetic fungicides.


Assuntos
Aflatoxinas/antagonistas & inibidores , Antifúngicos/farmacologia , Aspergillus flavus/efeitos dos fármacos , Óleos Voláteis/farmacologia , Rosmarinus/química , Antifúngicos/análise , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise
16.
J Photochem Photobiol B ; 202: 111678, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31734433

RESUMO

Potted herbs such as basil are in high year-round demand in Central Europe. To ensure good quality in winter, artificial light is required. Many horticulturists, who want to replace their high-pressure­sodium (HPS) lamps with light-emitting diodes (LEDs) to save electricity energy, struggle with high investment costs. In addition, switching to LEDs can overwhelm many smaller horticultural enterprises since there is a requirement of adjusting individual light recipes and furthermore cultivation problems can occur due to the lack of infrared radiation. In this study, the influence of light from microwave plasma lamps (MPL), acting as alternative light sources, on secondary metabolites and morphology of basil plants (Ocimum basilicum L.) was tested. Basil plants were grown in a climate chamber with MPL with two different light bulbs emitting either artificial sunlight (AS) or broad white light with increased blue and green light content (sulfur plasma light; SPL). The effect of these new lamp types was compared to standard commercial HPS lamps. In addition to morphological parameters such as height, internode length and fresh weight, plant secondary metabolites were examined. Essential oils and monoterpenes were quantified by GC-MS analysis, whereby phenolic compounds were analyzed calorimetrically. Elongation growth and biomass production was increased under the AS spectrum in comparison to HPS-grown plants. Increased stem elongation was attributed to a higher content of far-red light in the AS spectrum. Furthermore, basil plants grown under the AS spectrum contained the highest total phenolic and total flavonoid content compared to plants grown under the SPL and HPS lamps, probably due to the higher content of UV-A radiation. The lowest content of phenolic compounds was observed when HPS light was used, which was assumed to be caused by a low blue light content in the emission spectrum. An impact of the different light spectra on essential oil composition was determined. A significantly increased content of linalool was found in basil leaves developed under both tested MPL spectra compared to HPS-grown plants. The total yield of the four major essential oils was lowest under HPS treatment.


Assuntos
Luz , Ocimum basilicum/química , Compostos Fitoquímicos/química , Gases em Plasma/química , Biomassa , Clorofila/análise , Flavonoides/análise , Cromatografia Gasosa-Espectrometria de Massas , Micro-Ondas , Ocimum basilicum/crescimento & desenvolvimento , Ocimum basilicum/metabolismo , Óleos Voláteis/análise , Fenóis/análise , Compostos Fitoquímicos/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Análise de Componente Principal
17.
Nat Prod Res ; 34(3): 441-444, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600707

RESUMO

The hydro-distilled essential oil from aerial parts of Orthosiphon pallidus Royle, ex Benth (Lamiaceae) was investigated by using gas chromatography equipped with a flame ionisation detector (GC-FID) and gas chromatography coupled with a mass spectrometry (GC-MS). Fifty-two compounds, representing 98.4% of the total oil constituents, were identified. The major constituents were ß-caryophyllene (17.4%) and 7-epi-α-selinene (15.2%). The other minor constituents were terpinolene (6.9%), ß-pinene (6.8%), ß-elemene (5.1%), α-humulene (4.9%), α-copaene (4.8%), epi-cubebol (4.5%) and zonarene (3.9%). The oil was found to be rich in sesquiterpene hydrocarbon type constituents. Lamiaceae[Formula: see text].


Assuntos
Óleos Voláteis/análise , Orthosiphon/química , Monoterpenos Bicíclicos/análise , Monoterpenos Cicloexânicos/análise , Cromatografia Gasosa-Espectrometria de Massas , Lamiaceae/química , Sesquiterpenos Monocíclicos/análise , Óleos Voláteis/química , Sesquiterpenos Policíclicos/análise , Sesquiterpenos/análise
18.
J Chromatogr A ; 1610: 460567, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31629492

RESUMO

Qualitative and quantitative determination of volatile markers in aqueous based fragrances assumes ever-increasing importance, because of both the need for quality control and the safety-regulatory limitations introduced for several compounds. This study reports and critically discusses the results of applying new water-compatible ionic-liquid (IL) GC stationary phases, based on phosphonium and imidazolium derivative cations combined with trifluoromethanesulphonate (Watercol™) to the direct quantitative analysis of aqueous samples in the perfume field with GC-MS. Narrow-bore columns of different lengths, especially prepared for this study, were adopted to minimize the amount of water reaching the MS detector after GC separation. All GC-MS analysis steps were investigated, to achieve results compatible with quality control requirements for the volatiles of interest in this field, in terms of LODs, LOQs, and repeatability. Reliability of the GC-MS results was demonstrated by determining volatile allergens in two commercial perfumes, as per EU regulations concerning no-declaration limits for leave-on (0.001%) and rinse-off (0.01%) cosmetic products.


Assuntos
Alérgenos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Líquidos Iônicos/química , Óleos Voláteis/análise , Perfumes/análise , Água/química , Limite de Detecção , Odorantes/análise , Padrões de Referência , Reprodutibilidade dos Testes
19.
Food Microbiol ; 86: 103348, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703879

RESUMO

The effects of the incorporation of the essential oils from Origanum vulgare L. (OVEO; 0.07 µL/g) and Rosmarinus officinalis L. (ROEO; 2.65 µL/g) in combination in Minas Frescal cheese on the counts of the probiotic Lactobacillus acidophilus LA-5 and Escherichia coli O157:H7 were evaluated during refrigerated storage (7 ±â€¯0.5 °C). The terpenes of OVEO and ROEO, survival of the probiotic strain during in vitro digestion, as well as the physicochemical and sensory aspects were also monitored in Minas Frescal cheese. All terpenes decreased in cheese when the storage time increased. The incorporation of OVEO and ROEO delayed the increase in L. acidophilus LA-5 counts in cheese, but did not affect its ability to survive in cheese under simulated gastrointestinal conditions. The decreases in counts of E. coli O157:H7 observed in the first 15 days of refrigerated storage were strongly correlated (r ≥ 0.82) with the terpenes detected in cheese. Scores attributed for aroma, flavor, overall impression and purchase intention of cheese with OVEO and ROEO increased with the increase of the storage time. The incorporation of OVEO and ROEO in combination could be a strategy to control E. coli O157:H7 in probiotic Minas cheese during storage; however, the amounts of these substances should be cautiously selected considering possible negative sensory impacts in this product.


Assuntos
Queijo/microbiologia , Escherichia coli O157/crescimento & desenvolvimento , Aditivos Alimentares/análise , Lactobacillus acidophilus/crescimento & desenvolvimento , Óleos Voláteis/análise , Origanum/química , Óleos Vegetais/análise , Rosmarinus/química , Queijo/análise , Escherichia coli O157/efeitos dos fármacos , Aditivos Alimentares/farmacologia , Humanos , Lactobacillus acidophilus/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Paladar
20.
J Pharm Biomed Anal ; 177: 112849, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31499429

RESUMO

Herbal extracts and essential oils have been used over the centuries for their dietary, cosmetic and therapeutic properties. Quality control is needed to guarantee the safety and quality of these consumables. In this regard, fingerprinting techniques are important for inspection of the authenticity and for quality control. Analytical fingerprinting techniques provide signals related to the composition of a matrix (oil, plant extract, food…). The resulting fingerprint (spectrum or chromatogram) obtained for an untargeted or targeted approach is coupled to chemometric data processing, which may allow, for instance, the desired identification or discrimination of the sample considered. In this context, recent advances in untargeted/targeted fingerprinting approaches (especially chromatographic and spectroscopic) were described and their application in the taxonomic identification, classification and authentication of plants (medicinal) and essential oils discussed. An overview of the applications of untargeted/targeted fingerprinting techniques on herbal-extracts and essential-oils analysis, using different chemometric tools, has been included.


Assuntos
Técnicas de Química Analítica/métodos , Óleos Voláteis/análise , Extratos Vegetais/análise , Plantas Medicinais/química , Controle de Qualidade , Geografia , Metabolômica/métodos , Óleos Voláteis/química , Extratos Vegetais/química , Plantas Medicinais/classificação
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