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1.
São Paulo; s.n; s.n; 2022. 87 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-1379165

RESUMO

Um dos principais grupos de conservantes utilizados na maioria dos cosméticos são os parabenos que em muitos estudos demonstraram que podem provocar reações alérgicas como dermatite de contato, entre outras sensibilizações cutâneas. A fim de minimizar esses problemas, a indústria está produzindo cosméticos livres de conservantes ou de origem natural e em associações aos sintéticos. Dentre os conservantes naturais utilizados, podemos citar os óleos essenciais como uma alternativa viável. Diante deste contexto o presente trabalho visa avaliar experimentalmente o potencial antimicrobiano do óleo essencial de Conobea scoparioides Cham. & Schltdl., conhecida popularmente como pataqueira, o efeito de sua associação com parabenos e de sua eficácia como conservante em bases cosméticas. A composição do óleo essencial foi avaliada, indicando que este é composto em sua maior parte por terpenos, tendo éter metílico do timol (39,2%), timol (33,8 %) e α-felandreno (15,9%) como compostos majoritários. A atividade antimicrobiana do óleo essencial e do timol foi acessada através da concentração inibitória mínima (CIM), cujos resultados em µg/mL para o óleo essencial e o timol foram respectivamente: Staphylococcus aureus 650,70 e 284,90, Escherichia coli 721,53 e 271,20, Pseudomonas aeruginosa 1748,00 e > 2.000, Burkholderia cepacia 833,03 e 1.077,70, Candida albicans 521,43 e 172,61 e Aspergillus brasiliensis 300 e 400. O efeito sinérgico da associação do óleo essencial com os parabenos foi realizado através de um delineamento experimental centroide simplex para uma mistura de metilparabeno, propilparabeno e óleo essencial frente aos mesmos micro-organismos utilizados na determinação da atividade antimicrobiana. As concentrações ideais obtidas pela análise estatística para cada componente em µg/mL foram: 1120 para o metilparabeno, 350 para o propilparabeno e 675 para o óleo essencial. O teste de eficácia do sistema conservante em formulação cosmética foi efetuado empregando as concentrações ideais e mais duas concentrações superiores e uma abaixo do ideal. Para todas as cepas microbianas desafiadas o resultado do teste foi de redução total da carga microbiana inoculada nos sete dias de ensaio e nenhum aumento até o vigésimo oitavo dia o que demonstra a eficácia da associação do óleo essencial com os conservantes sintéticos. O óleo essencial de C. scoparioides apresentou um potencial antimicrobiano importante tanto sozinho como em associação com conservantes sintéticos. Estes resultados sugerem que esse óleo pode ser usado para compor um sistema conservante para formulações cosméticas contendo uma menor quantidade de sintéticos


One of the main groups of preservatives used in most cosmetics are parabens, that many studies have shown that they can cause allergic reactions such as contact dermatitis, among other skin sensitizations. To minimize these problems, the industry is producing cosmetics preservative free or using natural products instead and their combination with the synthetics. Among the natural preservatives used, we can mention essential oils as a viable alternative. In this context, the present work aims to experimentally evaluate the antimicrobial potential of the Conobea scoparioides Cham. & Schltdl. essential oil, popularly known as pataqueira, the effect of its association with parabens and its effectiveness as a preservative in cosmetic bases. The essential oil composition was analyzed, indicating that it is composed mostly of terpenes, with thymol methyl ether (39.2%), thymol (33.8%) and -phelandrene (15.9%) as major compounds. The antimicrobial activity of essential oil and thymol was accessed through the minimum inhibitory concentration (MIC), whose results in µg/mL for essential oil and thymol were respectively: Staphylococcus aureus 650.70 and 284.90, Escherichia coli 721, 53 and 271.20, Pseudomonas aeruginosa 1748.00 and > 2,000, Burkholderia cepacia 833.03 and 1,077.70, Candida albicans 521.43 and 172.61 and Aspergillus brasiliensis 300 and 400. The synergistic effect of the association of essential oil with parabens was performed through a centroid simplex experimental design for a mixture of methylparaben, propylparaben and essential oil against the same microorganisms used in the antimicrobial activity evaluation The ideal concentrations obtained by statistical analysis for each component in µg/mL were: 1120 for methylparaben, 350 for propylparaben and 675 for essential oil. The effectiveness test of the preservative system in cosmetic formulation was carried out using the ideal concentrations plus two higher concentrations and one below the ideal. For all challenged microbial strains, the test result was a total reduction of the inoculated microbial load in the seven days of testing and no increase until the twenty-eighth day, which demonstrates the effectiveness of the association of essential oil with synthetic preservatives. C. scoparioides essential oil showed an important antimicrobial potential both alone and in association with parabens. These results demonstrated that it can be used to compose a preservative system for cosmetic formulations containing lower amounts of synthetics


Assuntos
Aspergillus/classificação , Óleos Voláteis/análise , Cosméticos , Plantaginaceae/classificação , Parabenos/farmacologia , Pele , Burkholderia cepacia/classificação , Aditivos em Cosméticos , Anti-Infecciosos/efeitos adversos
2.
Sci Rep ; 10(1): 10691, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32612150

RESUMO

Plants exude a diverse cocktail of metabolites into the soil as response to exogenous and endogenous factors. So far, root exudates have mainly been studied under artificial conditions due to methodological difficulties. In this study, each five perennial grass and forb species were investigated for polar and semi-polar metabolites in exudates under field conditions. Metabolite collection and untargeted profiling approaches combined with a novel classification method allowed the designation of 182 metabolites. The composition of exuded polar metabolites depended mainly on the local environment, especially soil conditions, whereas the pattern of semi-polar metabolites was primarily affected by the species identity. The profiles of both polar and semi-polar metabolites differed between growth forms, with grass species being generally more similar to each other and more responsive to the abiotic environment than forb species. This study demonstrated the feasibility of investigating exudates under field conditions and to identify the driving factors of exudate composition.


Assuntos
Exsudatos de Plantas/metabolismo , Raízes de Plantas/metabolismo , Poaceae/metabolismo , Asteraceae/classificação , Asteraceae/metabolismo , Ecossistema , Cromatografia Gasosa-Espectrometria de Massas , Pradaria , Fenômenos Fisiológicos Vegetais , Plantaginaceae/classificação , Plantaginaceae/metabolismo , Poaceae/classificação , Ranunculaceae/classificação , Ranunculaceae/metabolismo , Rizosfera , Rubiaceae/classificação , Rubiaceae/metabolismo
3.
Phytochem Anal ; 30(2): 237-252, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30511497

RESUMO

INTRODUCTION: In the quest for new sources of biologically-active compounds, the chemical, and biological profiles of two Globularia species (G. trichosantha Fisch. & C. A. Mey and G. orientalis L.) were investigated. METHODOLOGY: Chemical profiles were evaluated by high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS), as well as by their total phenolic, flavonoids, and phenolic acids contents. The antioxidant abilities of the investigated extracts were done using different assays including free radical scavenging [1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS)], reducing power (cupric reducing antioxidant capacity and ferric reducing antioxidant power), phosphomolybdenum, and metal chelating. Inhibitory potential against key enzymes involved in neurodegenerative diseases (cholinesterases; AChE, and BChE), diabetes (α-glucosidase and α-amylase), hyperpigmentation (tyrosinase) and obesity (pancreatic lipase) were evaluated. RESULTS: Globularia trichosantha and G. orientalis extracts showed remarkable antioxidant properties, with the water extracts being a better source of antioxidant compounds. Both species showed remarkable inhibitory effects against the target enzymes. However, for both species, only the acetyl acetate and methanolic extracts were potent against cholinesterases and lipase. CONCLUSION: HPLC-ESI-QTOF-MS analysis revealed the presence of 107 compounds from G. trichosantha and G. orientalis, among which, 43 compounds have been preliminarily characterised for the first time from the Globulariaceae family. To date, this study can be considered as the most comprehensive research focused on the characterisation of G. trichosantha and G. orientalis. Results amassed from this study tend to show that these plants represent a rich source of biologically active compounds which can be further explored and validated for their therapeutic potential.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Plantaginaceae/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Antioxidantes/química , Antioxidantes/farmacologia , Quelantes/química , Flavonoides/química , Medicina Herbária , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantaginaceae/classificação , Especificidade da Espécie
4.
Sci Rep ; 8(1): 18079, 2018 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-30591708

RESUMO

The Balearic Islands, Corsica and Sardinia (BCS) constitute biodiversity hotspots in the western Mediterranean Basin. Oligocene connections and long distance dispersal events have been suggested to cause presence of BCS shared endemic species. One of them is Cymbalaria aequitriloba, which, together with three additional species, constitute a polyploid clade endemic to BCS. Combining amplified fragment length polymorphism (AFLP) fingerprinting, plastid DNA sequences and morphometrics, we inferred the phylogeography of the group and evaluated the species' current taxonomic circumscriptions. Based on morphometric and AFLP data we propose a new circumscription for C. fragilis to additionally comprise a group of populations with intermediate morphological characters previously included in C. aequitriloba. Consequently, we suggest to change the IUCN category of C. fragilis from critically endangered (CR) to near threatened (NT). Both morphology and AFLP data support the current taxonomy of the single island endemics C. hepaticifolia and C. muelleri. The four species had a common origin in Corsica-Sardinia, and two long-distance dispersal events to the Balearic Islands were inferred. Finally, plastid DNA data suggest that interspecific gene flow took place where two species co-occur.


Assuntos
Código de Barras de DNA Taxonômico , Filogenia , Filogeografia , Dispersão Vegetal , Plantaginaceae/classificação , Plantaginaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Biodiversidade , DNA de Plantas , França , Variação Genética , Itália , Plastídeos/genética , Espanha
5.
Mol Ecol Resour ; 18(6): 1492-1499, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30010236

RESUMO

Phylogeny reconstruction is a key instrument in numerous biological analyses, ranging from evolutionary and ecology research, to conservation and systems biology. The increasing accumulation of genomic data makes it possible to reconstruct phylogenies with both high accuracy and at increasingly finer resolution. Yet, taking advantage of the enormous amount of sequence data available requires the use of computational tools for efficient data retrieval and processing, or else the process could quickly become an error-prone endeavour. Here, we present OneTwoTree (http://onetwotree.tau.ac.il/), a Web-based tool for tree reconstruction based on the supermatrix paradigm. Given a list of taxa names of interest as the sole input requirement, OneTwoTree retrieves all available sequence data from NCBI GenBank, clusters these into orthology groups, identifies the most informative set of markers, searches for an appropriate outgroup, and assembles a partitioned sequence matrix that is then used for the final phylogeny reconstruction step. OneTwoTree further allows users to control various steps of the process, such as the merging of sequences from similar clusters, or phylogeny reconstruction based on markers from a specific genome type. By comparing the performance of OneTwoTree to a manually reconstructed phylogeny of the Antirrhineae tribe, we show that the use of OneTwoTree resulted in substantially higher data coverage in terms of both taxon sampling and the number of informative markers assembled. OneTwoTree provides a flexible online tool for species-tree reconstruction, aimed to assist researchers ranging in their level of prior expertise in the task of phylogeny reconstruction.


Assuntos
Biologia Computacional/métodos , Filogenia , Internet , Plantaginaceae/classificação , Plantaginaceae/genética
6.
PLoS One ; 12(6): e0178827, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28582433

RESUMO

Effects of Pleistocene climatic oscillations on plant phylogeographic patterns are relatively well studied in forest, savanna and grassland biomes, but such impacts remain less explored on desert regions of the world, especially in South America. Here, we performed a phylogeographical study of Monttea aphylla, an endemic species of the Monte Desert, to understand the evolutionary history of vegetation communities inhabiting the South American Arid Diagonal. We obtained sequences of three chloroplast (trnS-trnfM, trnH-psbA and trnQ-rps16) and one nuclear (ITS) intergenic spacers from 272 individuals of 34 localities throughout the range of the species. Population genetic and Bayesian coalescent analyses were performed to infer genealogical relationships among haplotypes, population genetic structure, and demographic history of the study species. Timing of demographic events was inferred using Bayesian Skyline Plot and the spatio-temporal patterns of lineage diversification was reconstructed using Bayesian relaxed diffusion models. Palaeo-distribution models (PDM) were performed through three different timescales to validate phylogeographical patterns. Twenty-five and 22 haplotypes were identified in the cpDNA and nDNA data, respectively. that clustered into two main genealogical lineages following a latitudinal pattern, the northern and the southern Monte (south of 35° S). The northern Monte showed two lineages of high genetic structure, and more relative stable demography than the southern Monte that retrieved three groups with little phylogenetic structure and a strong signal of demographic expansion that would have started during the Last Interglacial period (ca. 120 Ka). The PDM and diffusion models analyses agreed in the southeast direction of the range expansion. Differential effect of climatic oscillations across the Monte phytogeographic province was observed in Monttea aphylla lineages. In northern Monte, greater genetic structure and more relative stable demography resulted from a more stable climate than in the southern Monte. Pleistocene glaciations drastically decreased the species area in the southern Monte, which expanded in a southeastern direction to the new available areas during the interglacial periods.


Assuntos
DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Modelos Estatísticos , Filogenia , Dispersão Vegetal/fisiologia , Plantaginaceae/genética , Argentina , Teorema de Bayes , Clima Desértico , Variação Genética , Haplótipos , História do Século XXI , História Antiga , Filogeografia , Plantaginaceae/classificação , Análise Espaço-Temporal
7.
Rev. bras. plantas med ; 14(4): 635-642, 2012. ilus
Artigo em Português | LILACS | ID: lil-664015

RESUMO

A infusão das folhas de Plantago major (Plantaginaceae), conhecida como tansagem ou transagem, é usada como antibiótica, antiinflamatória, anti-séptica, anti-térmica, na prevenção de tumores e no tratamento de neoplasias. Este efeito é atribuído aos flavonóides encontrados em diversas espécies do gênero Plantago. O presente estudo objetivou avaliar os potenciais efeitos, tóxico e mutagênico, do extrato bruto hidroalcoólico de folhas de P. major, por meio dos testes in vivo de Allium cepa e do micronúcleo. Para o ensaio biológico vegetal, meristemas de raízes de A. cepa foram usados para o preparo de lâminas através da técnica de esmagamento. No ensaio do micronúcleo foram analisadas lâminas de células de medula óssea de roedores. As análises estatísticas seguiram o teste de Tukey (p<0,05) para o ensaio de Allium cepa e teste de Scott-Knott (p<0,05) para o ensaio do micronúcleo. Os resultados do teste de Allium cepa demonstram que houve redução significativa no índice de germinação em todas as concentrações testadas. P. major provoca alteração no ciclo celular pela inibição da divisão das células, como indica o índice mitótico. Os índices de efeitos clastogênico e aneugênico demonstram que, além de não determinar aumento de aberrações cromossômicas, o que indica ausência de ação genotóxica, P. major possui atividade anti-genotóxica. Os resultados do teste do micronúcleo reforçam a sugestão de que o extrato de P.major não possui atividade mutagênica, entretanto provoca alterações na divisão celular.


The infusion of leaves of Plantago major (Plantaginaceae), known as "tansagem" or "transagem", is used as antibiotic, anti-inflammatory, anti-septic, anti-thermal in the prevention of tumors and in the treatment of neoplasms. This effect is attributed to the flavonoids found in diverse species of the genus Plantago. The present study aimed to evaluate the potential toxic and mutagenic effects of the crude hydroalcoholic extract from P. major leaves by means of in vivo tests with Allium cepa and micronucleus. For the plant biological assay, meristems of A. cepa roots were used for the preparation of slides by adopting the crushing technique. In the micronucleus assay, slides of bone marrow cells from rodents were analyzed. Statistical analyses were carried out according to Tukey's test (ρ<0.05) for the Allium cepa assay and Scott-Knott test (ρ<0.05) for the micronucleus assay. Results of the A. cepa test demonstrate that there was a significant reduction in the germination index at all tested concentrations. P. major causes alteration in the cell cycle by inhibiting the division of cells, as indicated by the mitotic index. The indexes of clastogenic and aneugenic effects show that, in addition to not determining the increase in chromosomal aberrations, which indicates the absence of genotoxic action, P. major has anti-genotoxic activity. Results of the micronucleus test reinforce the suggestion that P. major extract does not have mutagenic activity but causes alterations in the cell division.


Assuntos
Citotoxinas/análise , Genotoxicidade , Plantas Medicinais/metabolismo , Mutagênese , Cebolas , Plantaginaceae/classificação
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