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1.
Phytochemistry ; 192: 112898, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34492545

RESUMO

Lychnophora pinaster Mart. (Asteraceae) is endemic to the Brazilian Cerrado. It is distributed along the altitudinal gradient of the mountainous ranges of the state of Minas Gerais. This study aimed to evaluate the influence of altitude on the genetic diversity of L. pinaster populations and the effects of altitude and climatic factors on essential oil chemical composition. Essential oils from L. pinaster populations from the north (North 01, North 02, and North 03, 700-859 m) and the Metropolitan region of Belo Horizonte (MhBH 01 and MrBH 02, 1366-1498 m) were analyzed. SNP markers from L. pinaster in these regions and Campos das Vertentes (CV 01, CV 02, and CV 03, 1055-1292 m) were also analyzed. The main compounds in essential oils were 14-hydroxy-α-humulene (North 01 and North 03), cedr-8(15)-en-9-α-ol (North 02), 14-acetoxy-α-humulene (MrBH 01), and 4-oxo-15-nor-eudesman-11-ene (MrBH 02). Hierarchical cluster and heatmap analyses showed that the North and MrBH populations included five different groups, indicating the chemical composition of essential oils is distinct in each population. Furthermore, principal component analysis showed that higher altitudes (1366 m and 1498 m) in the MrBH influence the chemical composition of essential oils, and climatic factors determine the chemical composition in North region. The genetic diversity showed that most alleles are in Hardy-Weinberg equilibrium and imply high genetic variation and genetic polymorphisms between populations. Furthermore, the results of Mantel tests (R = 0.3861517; p = 0.04709529; R = 0.9423121; p = 0.02739726) also showed that higher altitude (>1360 m) shapes the genetic diversity at the MrBH. The genetic structure showed that higher altitudes (>1360 m) contribute to the structure of the MrBH populations, but not to North and CV populations. Therefore, the altitudinal ranges of Minas Gerais mountainous ranges determine the higher genetic and chemical diversity of L. pinaster populations.


Assuntos
Altitude , Asteraceae , Óleos Voláteis , Óleos de Plantas/química , Asteraceae/química , Asteraceae/genética , Brasil , Genômica , Óleos Voláteis/química , Análise de Componente Principal
2.
Planta ; 252(6): 103, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33185761

RESUMO

MAIN CONCLUSION: Nicotiana tabacum overexpressing CrSAMT from Citrus reticulata increased production of MeSA, which works as an airborne signal in neighboring wild-type plants, inducing PR1 and increasing resistance to the pathogen Xylella fastidiosa. Xylella fastidiosa is one of the major threats to plant health worldwide, affecting yield in many crops. Despite many efforts, the development of highly productive resistant varieties has been challenging. In studying host plant resistance, the S-adenosyl-L-methionine: salicylic acid carboxyl methyltransferase gene (SAMT) from Citrus reticulata, a X. fastidiosa resistant species, was upregulated in response to pathogen infection. SAMT is involved with the catalysis and production of methyl salicylate (MeSA), an airborne signal responsible for triggering systemic acquired resistance. Here we used tobacco as a model system and generated transgenic plants overexpressing C. reticulata SAMT (CrSAMT). We performed an in silico structural characterization of CrSAMT and investigated its biotechnological potential in modulating the immune system in transgenic plants. The increase of MeSA production in transgenic lines was confirmed by gas chromatography (GC-MS). The transgenic lines showed upregulation of PR1, and their incubation with neighboring wild-type plants activated PR1 expression, indicating that MeSA worked as an airborne signal. In addition, transgenic plants showed significantly fewer symptoms when challenged with X. fastidiosa. Altogether, these data suggest that CrSAMT plays a role in host defense response and can be used in biotechnology approaches to confer resistance against X. fastidiosa.


Assuntos
Citrus , Expressão Gênica , Metiltransferases , Salicilatos , Xylella , Citrus/genética , Citrus/microbiologia , Metiltransferases/genética , Metiltransferases/metabolismo , Doenças das Plantas , Proteínas Recombinantes/genética , Salicilatos/química , Nicotiana/genética , Volatilização , Xylella/fisiologia
3.
Plant Dis ; 104(2): 414-422, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31841378

RESUMO

The fungus Austropuccinia psidii is a major pathogen of Eucalyptus spp. that damages mainly early-stage leaves. Resistant clones are the most widely used control measure for the rust disease caused by A. psidii. Essential oils produced in the plant-host cells are associated with resistance. However, the chemical characteristics of Eucalyptus leaves at different stages of maturity, associated with resistance or susceptibility to A. psidii, need to be determined. The aims of this study were to characterize the chemical composition of essential oils in Eucalyptus leaves at three developmental stages of clones of three E. urophylla × E. grandis hybrids that exhibit different resistance levels to rust and to identify probable resistance-related compounds from them. The rust severity following inoculation and the quantity and quality of the essential oil extracted by hydrodistillation were determined at the first, third, and fifth leaf stages of the three clones. Identification of the compounds present in the essential oil was determined by gas chromatography coupled with mass spectrometry. No rust was observed on the three leaf stages of the resistant clone or on the fifth leaf stage of the susceptible clones. Limonene was found at high percentages in essential oils from the three leaf stages of the resistant clone and at low percentages in the susceptible clones. In vitro and in vivo tests indicated that low limonene percentages stimulated A. psidii urediniospore germination and were not fungitoxic, whereas high percentages caused complete inhibition of germination and degenerative changes in fungal reproductive structures. The limonene present in Eucalyptus leaves can be considered a chemical compound related to the rust resistance of Eucalyptus spp.


Assuntos
Basidiomycota , Eucalyptus , Limoneno , Doenças das Plantas , Folhas de Planta
4.
Anal Bioanal Chem ; 410(19): 4749-4762, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29806067

RESUMO

In this study, a series of polymeric ionic liquid (PIL) sorbent coatings is evaluated for the extraction of polar volatile organic compounds (VOCs) from Brazilian wines using headspace solid-phase microextraction (HS-SPME), including samples from 'Isabella' and 'BRS Magna' cultivars-the latter was recently introduced by the Brazilian Agricultural Research Corporation - National Grape & Wine Research Center. The structurally tuned SPME coatings were compared to the commercial SPME phases, namely poly(acrylate) (PA) and divinylbenzene/carboxen/poly(dimethylsiloxane) (DVB/CAR/PDMS). The separation, detection and identification of the aroma profiles were obtained using comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS). The best performing PIL-based SPME fiber, namely 1-hexadecyl-3-vinylimidazolium bis[(trifluoromethyl)sulfonyl]imide with 1,12-di(3-vinylimidazolium)dodecane dibis[(trifluoromethyl)sulfonyl]imide incorporated cross-linker supported on an elastic nitinol wire, exhibited superior performance to DVB/CAR/PDMS regarding the average number of extracted peaks and extracted more polar analytes providing additional insight into the aroma profile of 'BRS Magna' wines. Four batches of wine were evaluated, namely 'Isabella' and 'BRS Magna' vintages 2015 and 2016, using highly selective PIL-based SPME coatings and enabled the detection of 350+ peaks. Furthermore, this is the first report evaluating the aroma of 'BRS Magna' wines. A hybrid approach that combined pixel-based Fisher ratio and peak table-based data comparison was used for data handling. This proof-of-concept experiment provided reliable and statistically valid distinction of wines that may guide regulation agencies to create high sample throughput protocols to screen wines exported by Brazilian vintners. Graphical abstract Highly selective extraction of wine aroma using polymeric ionic liquid.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Líquidos Iônicos/química , Odorantes/análise , Microextração em Fase Sólida/métodos , Vinho/análise , Brasil , Análise Discriminante , Polímeros/química
5.
Mar Drugs ; 15(10)2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28954390

RESUMO

Padina sanctae-crucis Børgesen is distributed worldwide in tropical and subtropical seas; belongs to the Dictyotaceae family, and has proven to be an exceptional source of biologically active compounds. Four compounds were isolated and identified, namely: dolastane diterpene new for the genus Padina; phaeophytin and hidroxy-phaeophytin new for the family Dictyotaceae, and; mannitol first described in this species. Saturated fatty acids as compared to the percentages of unsaturated fatty acids were shown to be present in greater abundance. Palmitic and linolenic acid were the main saturated and unsaturated acids, respectively. Cytotoxic and antioxidant activities were evaluated using human erythrocytes. In vivo evaluations of acute toxicity and genotoxicity were performed in mice. Methanolic extract of P.sanctae-crucis presented antioxidant activity and did not induce cytotoxicity, genotoxicity or acute toxicity. Since Padina sanctae-crucis is already used as food, has essential fatty acids for the nutrition of mammals, does not present toxicity and has antioxidant activity, it can be considered as a potential nutraceutical.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/farmacologia , Phaeophyceae/química , Animais , Antioxidantes/farmacologia , Suplementos Nutricionais , Eritrócitos/efeitos dos fármacos , Ácidos Graxos/farmacologia , Ácidos Graxos Insaturados/farmacologia , Feminino , Humanos , Masculino , Metanol/química , Camundongos , Testes de Mutagenicidade/métodos , Ácido Palmítico/farmacologia , Ácido alfa-Linolênico/farmacologia
6.
Appl Plant Sci ; 4(3)2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27011894

RESUMO

PREMISE OF THE STUDY: Baccharis dracunculifolia (Asteraceae) is a native plant of the Atlantic Forest that is used for the production of essential oil. Microsatellite markers were developed for this species to investigate the genetic diversity of three natural populations. METHODS AND RESULTS: Seventeen out of 27 microsatellite loci identified in a genomic library used for the characterization of 315 individuals derived from three natural populations of B. dracunculifolia resulted in successful amplifications. Eleven polymorphic loci, ranging from two to seven alleles per locus, were obtained with expected and observed heterozygosity values ranging between 0.068 and 0.775 and 0.046 and 0.667, respectively. CONCLUSIONS: The microsatellite loci described in this study are tools that can be used for further studies of population genetics of B. dracunculifolia with a focus on deforested areas and conservation of natural populations.

7.
An Acad Bras Cienc ; 87(2): 943-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131639

RESUMO

The essential oils from leaves and inflorescences of Lippia origanoides Kunth present aromatic and medicinal potential and have been used to treat several diseases, including melanoma. In Brazil, L. origanoides is commonly found in campo cerrado and cerrado stricto sensu, physiognomies featured mainly by the differential light conditions to which short and medium-sized plants are subjected. Our aim was to investigate the glandular trichome density and the yield and chemical composition of the essential oils in leaves and inflorescences of L. origanoides from campo cerrado and cerrado stricto sensu. For glandular density analysis, leaves and inflorescences were processed according to conventional techniques for scanning electron microscopy. The essential oils of leaves and inflorescences were obtained by hydrodistillation and identified with gas chromatography. Bracts and sepals showed the highest glandular density, followed by petals and leaves. The glandular density in the abaxial leaf surface was higher in individuals from the campo cerrado. In both populations the essential oil yield was higher in inflorescences than in leaves. The chemical composition of the essential oils varied among individuals from different areas and inside a same population. Our results demonstrated the chemical plasticity of L. origanoides suggesting the importance of monitoring its popular use.


Assuntos
Lippia/química , Lippia/ultraestrutura , Óleos Voláteis/química , Folhas de Planta/química , Folhas de Planta/ultraestrutura , Tricomas/ultraestrutura , Brasil , Cromatografia Gasosa , Inflorescência , Microscopia Eletrônica de Varredura
8.
Front Microbiol ; 5: 269, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24926289

RESUMO

Aflatoxin B1 (AFB1) is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oils of Ageratum conyzoides (mentrasto) and Origanum vulgare (oregano) on the mycelial growth and aflatoxin B1 production by Aspergillus flavus have been studied previously in culture medium. The aim of this study was to evaluate aflatoxin B1 production by Aspergillus flavus in real food systems (corn and soybean) treated with Ageratum conyzoides (mentrasto) and Origanum vulgare (oregano) essential oils. Samples with 60 g of the grains were treated with different volumes of essential oils, 200, 100, 50, and 10 µL for oregano and 50, 30, 15, and 10 µL for mentrasto. Fungal growth was evaluated by disk diffusion method. Aflatoxin B1 production was evaluated inoculating suspensions of A. flavus containing 1.3 × 10(5) spores/mL in 60 g of grains (corn and soybeans) after adjusting the water activity at 0.94. Aflatoxin was quantified by photodensitometry. Fungal growth and aflatoxin production were inhibited by essential oils, but the mentrasto oil was more effective in soybeans than that of oregano. On the other hand, in corn samples, the oregano essential oil was more effective than that of mentrasto. Chemical compositions of the essential oils were also investigated. The GC/MS oils analysis showed that the main component of mentrasto essential oil is precocene I and of the main component of oregano essential oil is 4-terpineol. The results indicate that both essential oils can become an alternative for the control of aflatoxins in corn and soybeans.

9.
Rev. bras. farmacogn ; 22(1): 40-44, Jan.-Feb. 2012. tab
Artigo em Inglês | LILACS | ID: lil-607595

RESUMO

Melissa officinalis L., Lamiaceae, is an herb with great growth prospects in the cosmetic industry due to its essential oil. In order to improve its production, it is necessary to study related agricultural practices. This study evaluated the effect of organic and mineral fertilization on the chemical composition of lemon balm (Melissa officinalis L.) essential oil. The assay was conducted at the "Fazenda Experimental do Glória" of the Federal University of Uberlândia, and essential oil extraction and GC/MS analyses were completed by the Centre for Research and Development on Plant Genetic Resources of the Campinas Agronomic Institute. The assay was conducted in a randomized complete block design with three replications. The tested treatments were six types of fertilization (0, 1, 2, 4, 8 kg.m-2 of cattle manure and mineral fertilizing with 60 g.m-2 of NPK 4-14-8 + 4 g.m-2 of boric acid) with four replications. The essential oil was extracted by hydrodistillation in a modified Clevenger apparatus. The chemical composition was analyzed by GC/MS. The essential oil presented the same compounds for all treatments; however, the relative proportion of some chemical constituents was altered according to the treatment. Neral, geranial, and citronellal were the major constituents.

10.
Int J Food Microbiol ; 137(1): 55-60, 2010 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-19906457

RESUMO

Aflatoxin B(1) (AFB(1)) is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oil of Ageratum conyzoides, on the mycelial growth and aflatoxin B(1) production by Aspergillus flavus were studied. Cultures were incubated in yeast extract-sucrose (YES) broth for days at 25 degrees C at the following different concentrations of the essential oil (from 0.0 to 30mug/mL). The essential oil inhibited fungal growth to different extents depending on the concentration, and completely inhibited aflatoxin production at concentrations above 0.10microg/mL. The analysis of the oil by GC/MS showed that its main components are precocene II (46.35%), precocene I (42.78%), cumarine (5.01%) and Trans-caryophyllene (3.02%). Comparison by transmission electron microscopy of the fungal cells, control and those incubated with different concentrations of essential oil, showed ultra-structural changes which were concentration dependent of the essential oil of A. conyzoides. Such ultra-structural changes were more evident in the endomembrane system, affecting mainly the mitochondria. Degradation was also observed in both surrounding fibrils. The ability to inhibit aflatoxin production as a new biological activity of A.conyzoides L. indicates that it may be considered as a useful tool for a better understanding of the complex pathway of aflatoxin biosynthesis.


Assuntos
Aflatoxina B1/antagonistas & inibidores , Ageratum/química , Aspergillus flavus/efeitos dos fármacos , Óleos de Plantas/farmacologia , Aflatoxina B1/biossíntese , Aflatoxina B1/toxicidade , Antifúngicos/química , Antifúngicos/farmacologia , Aspergillus flavus/crescimento & desenvolvimento , Aspergillus flavus/metabolismo , Aspergillus flavus/ultraestrutura , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Microscopia Eletrônica de Transmissão , Óleos de Plantas/química
11.
J Pharm Pharmacol ; 61(7): 933-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19589236

RESUMO

OBJECTIVES: The purpose of the present work was to characterize the pharmacological profile of different L. alba chemotypes and to correlate the obtained data to the presence of chemical constituents detected by phytochemical analysis. METHODS: Essential oils from each L. alba chemotype (LP1-LP7) were characterized by gas chromatography-mass spectrometry (GC-MS) and extracted non-volatile compounds were analysed by HPLC and GC-MS. The anticonvulsant actions of the extracted compounds were studied in pentylenetetrazole-induced clonic seizures in mice and their effect on motor coordination was studied using the rota-rod test in rats. The synaptosomes and synaptic membranes of the rats were examined for the influence of LP3 chemotype extract on GABA uptake and binding experiments. KEY FINDINGS: Behavioural parameters encompassed by the pentylenetetrazole test indicated that 80% ethanolic extracts of LP1, LP3 and LP6 L. alba chemotypes were more effective as anticonvulsant agents. Neurochemical assays using synaptosomes and synaptic membranes showed that L. alba LP3 chemotype 80% ethanolic extract inhibited GABA uptake and GABA binding in a dose-dependent manner. HPLC analysis showed that LP1, LP3 and LP6 80% ethanolic extracts presented a similar profile of constituents, differing from those seen in LP2, LP4, LP5 and LP7 80% ethanolic extracts, which exhibited no anticonvulsant effect. GC-MS analysis indicated the occurrence of phenylpropanoids in methanolic fractions obtained from LP1, LP3 and LP6 80% ethanolic extracts and also the accumulation of inositol and flavonoids in hydroalcoholic fractions. CONCLUSIONS: Our results suggest that the anticonvulsant properties shown by L. alba might be correlated to the presence of a complex of non-volatile substances (phenylpropanoids, flavonoids and/or inositols), and also to the volatile terpenoids (beta-myrcene, citral, limonene and carvone), which have been previously validated as anticonvulsants.


Assuntos
Anticonvulsivantes/uso terapêutico , Flavonoides/uso terapêutico , Lippia/química , Óleos Voláteis/uso terapêutico , Convulsões/tratamento farmacológico , Terpenos/uso terapêutico , Animais , Anticonvulsivantes/farmacologia , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Flavonoides/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Camundongos , Destreza Motora/efeitos dos fármacos , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Pentilenotetrazol , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Ratos , Ratos Wistar , Teste de Desempenho do Rota-Rod , Convulsões/induzido quimicamente , Terpenos/farmacologia , Ácido gama-Aminobutírico/metabolismo
12.
J Agric Food Chem ; 51(9): 2520-5, 2003 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-12696930

RESUMO

In the present study the antioxidant, anticancer, and antimycobacterial activities of extracts from ginger (Zingiber officinale Roscoe), rosemary (Rosmarinus officinalis L.), and turmeric (Curcuma longa L.) were evaluated. The extracts were obtained using supercritical CO(2) with and without ethanol and/or isopropyl alcohol as cosolvent. The extracts' antioxidant power was assessed using the reaction between beta-carotene and linolenic acid, the antimycobacterial activity against M. tuberculosis was measured by the MABA test, and their anticancer action was tested against nine human cancer ancestries: lung, breast, breast resistant, melanoma, colon, prostate, leukemia, and kidney. The rosemary extracts exhibited the strongest antioxidant and the lowest antimycobacterial activities. Turmeric extracts showed the greatest antimycobacterial activity. Ginger and turmeric extracts showed selective anticancer activities.


Assuntos
Curcuma/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Rosmarinus/química , Zingiber officinale/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Anticarcinógenos/isolamento & purificação , Anticarcinógenos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Dióxido de Carbono , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mycobacterium/efeitos dos fármacos , Mycobacterium/crescimento & desenvolvimento
13.
J Agric Food Chem ; 51(6): 1518-23, 2003 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-12617576

RESUMO

Supercritical fluid extraction (SFE) from aniseed using carbon dioxide was performed at 30 degrees C and pressures of 80-180 bar. The chemical composition of the SFE extract was determined by GC-MS; the quantitative analysis was done by GC-FID and TLC. The total amount of extractable substances or global yield (mass of extract/mass of feed) for the SFE process varied from 3.13 to 10.67% (mass). The solubilities of the anise essential oil in CO(2) were 0.0110, 0.0277, 0.0143, and 0.0182 kg of solute/kg of CO(2) at 80, 100, 140, and 180 bar, respectively. The major compounds identified and quantified in the extracts were anethole ( approximately 90%), gamma-himachalene (2-4%), p-anisaldehyde (<1%), methylchavicol (0.9-1.5%), cis-pseudoisoeugenyl 2-methylbutyrate ( approximately 3%), and trans-pseudoisoeugenyl 2-methylbutyrate ( approximately 1.3%). The Sovová model described quite well the experimental overall extraction curves.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Óleos Voláteis/química , Pimpinella/química , Dióxido de Carbono , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Solubilidade
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