Browsing by Author "Amparo, Tatiane Roquete"
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Item Análise fitoquímica e bioprospecção para atividade antimicrobiana de Protium spruceanum (Benth.) Engler.(2016) Amparo, Tatiane Roquete; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Brandão, Geraldo Célio; Vieira Filho, Sidney AugustoDevido ao crescimento de patógenos resistentes aos fármacos atuais, a pesquisa por novos antimicrobianos tem sido incentivada, principalmente através das plantas medicinais. A espécie vegetal Protium spruceanum (Benth.) Engler, conhecida como breu, é utilizada popularmente como antiinflamatório e expectorante, porém, há necessidade de expandir estudos sobre essa espécie. Dessa forma, os objetivos desse estudo foram a avaliação da atividade antimicrobiana e o estudo fiquímico dos extratos etanólicos brutos (EEBs) e frações de folhas e galhos de P. spruceanum. Através dos métodos de difusão em poço e microdiluição, observou-se a atividade antimicrobiana dos EEBs contra 20 micro-organismos. O EEB de folhas apresentou maior atividade antimicrobiana total (AAT) que o EEB de galhos. As frações mais ativas foram as acetatoetilênicas e hidrometanólicas que apresentam ação sinérgica entre si. Através do estudo fitoquímico, observou-se que a AAT dos EEBs e frações pode ser corelacionada majoritariamente ao teor de taninos totais, porém, propõe-se uma ação sinérgica com outros compostos, como flavonóides. Os constituintes voláteis majoritários foram identificados utilizando CG/EM, dentre eles ácidos graxos, fenólicos e terpenoides, como amirinas. A avaliação da mistura de α- e β-amirina mostrou que esta não apresenta forte atividade antimicrobiana e também não está relacionada ao sinergismo entre as frações. Através de CLUE/DAD/EM-EM também foi possível identificar flavonoides glicosilados (quercetina-3-O-ramnosídeo, quercetina-3-Oglicuronídeo e campeferol-3-O-ramnosídeo) e taninos (catequina e procianidina). Os resultados in silico gerados pela ferramenta PASSonline indicaram potencial efeito antibacteriano principalmente para os constituintes majoritários das frações AcOEt e HMeOH. Também foram indicados como principais mecanismos de ação: aumento da permebilidade da membrana celular, inibição da bissíntese da parede bacteriana (enzimas peptideoglicano glicosiltransferase e CDP-glicerol glicerofosfotransferase) e inibição do metabolismo (enzimas 2-deidropantoato 2-redutase e piruvato cinase). Esses mecanismos de ação são diferentes dos antibióticos recentes e são considerados alvos para novos fármacos.Item Anti-inflammatory activity of Protium spruceanum (Benth.) Engler is associated to immunomodulation and enzymes inhibition.(2019) Amparo, Tatiane Roquete; Seibert, Janaína Brandão; Mathias, Fernando Augusto Siqueira; Vieira, João Filipe Pereira; Soares, Rodrigo Dian de Oliveira Aguiar; Freitas, Katia Michelle; Cabral, Vivette Appolinário Rodrigues; Brandão, Geraldo Célio; Santos, Orlando David Henrique dos; Souza, Gustavo Henrique Bianco de; Vieira, Paula Melo de AbreuEthnopharmacological relevance: Protium spruceanum (Burseraceae) is used in Brazilian traditional medicine as anti-inflammatory, but the factors involved in this activity were not yet characterized. Aims of the study: analyze the aspects involved in the anti-inflammatory activity of polar fractions obtained from extracts of leaves and branches. Materials and methods: Hydromethanolic fraction was obtained by liquid-liquid partition from crude ethanolic extract and its compounds were identified by LC-DAD-MS. Activity tests were performed using LPS + IFN-γ stimulated J774A.1 macrophages. Cytokines were evaluated by CBA kit, NO by Griess method, ROS by DCFH-DA, N-acetylglucosaminidase (NAG) activity by spectrophotometric method, matrix-metalloproteinase (MMP-9) activity by zymography, inducible nitric oxide synthase (iNOS) expression by immunofluorescence and cyclooxygenase (COX-2) expression by Western blot. Results: Fractions induced an increase of IL-6 and IL-10 which leads to the control of pro-inflammatory cytokines levels. The treatment with the fractions also reduced NO production at all concentrations tested in all evaluated periods. ROS production by the macrophages was inhibited by the treatment and the leaves fraction showed the best results with a lower concentration than that observed for the branches. The enzymes assays showed that leaves fraction inhibited NAG and MMP-9 activities, as well as, iNOS and COX-2 expression. These activities can be associated with the presence of procyanidin, catechin, rutin, quercitrin, isoquercitrin and kaempferol-3-O-rhamnoside, major compounds that were identified in the fraction. Conclusions: Anti-inflammatory activity of P. spruceanum is associated to an immunomodulatory effect that leads to inhibition of ROS, NO, NAG, MMP-9, COX-2 and iNOS.Item Antibacterial activity of extract and fractions from branches of Protium spruceanum and cytotoxicity on fibroblasts.(2017) Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Seibert, Janaína Brandão; Souza, Rafaella Hilda Zaniti; Oliveira, Amanda Ribeiro de; Cabral, Vivette Appolinário Rodrigues; Vieira, Paula Melo de Abreu; Brandão, Geraldo Célio; Okuma, Adriana Akemi; Vieira Filho, Sidney Augusto; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco deThe crude ethanol extract (CEE) and fractions from branches of Protium spruceanum were subjected to antibacterial and cytotoxicity assays. Compounds of the most active fraction were identified by GC-MS and LC-MS. CEE was active against 19 bacteria and the ethyl acetate fraction (EAF) showed the lowest minimum bactericidal concentration (MBC 0.3–80.0 mg/mL). Through time-kill assay was observed that EAF induced rapid bactericidal effect against Staphylococcus saprophyticus. The cytotoxicity tests against L929 fibroblasts showed great potential of EAF on the treatment of infections caused by five bacteria (MBC < IC50). The results provide in vitro scientific support to the possible application of branches of P. spruceanum as antimicrobial agent that may contribute for treatment of infections.Item Antibacterial substances from leaves of Protium spruceanum (Burseraceae) : in vitro and in silico evaluation.(2020) Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Seibert, Janaína Brandão; Almeida, Tamires Cunha; Cabral, Vivette Appolinário Rodrigues; Vieira, Paula Melo de Abreu; Brandão, Geraldo Célio; Oliveira, Mauro Lúcio Gonçalves de; Silva, Glenda Nicioli da; Santos, Orlando David Henrique dos; Vieira Filho, Sidney Augusto; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco deDue to the increase of bacterial resistance, the search for new antibiotics is necessary and the medicinal plants represent its most important source. The aim of this study was to evaluate the antibacterial property of extract and fractions from Protium spruceanum leaves, against pathogenic bacteria. By means of diffusion and microdilution assays, the crude extract was active against the nine bacteria tested being the hydromethanolic fraction the most active. During phytochemical procedures, procyanidin (1) and catechin (2) were identified as the main antibacterial constituents of this fraction. In silico results obtained using PASSonline tool indicated 1 and 2 as having good potential to interact with different targets of currently used antibiotics. These results no indicated potential to none DNA effect and indicated the cell wall as mainly target. Electrophoresis result supported that had no DNA damage. Cell wall damage was confirmed by propidium iodide test that showed increased membrane permeability and by cell surface deformations observed in scanning electronic microscopy. The in vitro assays together with the in silico prediction results establish the potential of P. spruceanum as source of antibacterial compounds that acts on important bacterial targets. These results contribute to the development of natural substances against pathogenic bacteria and to discovery of new antibiotics.Item Antitumor effect of Cymbopogon densiflorus (Linneu) essential oil in bladder cancer cells.(2020) Pereira, Gizele Lucia da Costa; Almeida, Tamires Cunha; Seibert, Janaína Brandão; Amparo, Tatiane Roquete; Soares, Rodrigo Dian de Oliveira Aguiar; Rodrigues, Ivanildes Vasconcelos; Souza, Gustavo Henrique Bianco de; Santos, Orlando David Henrique dos; Silva, Glenda Nicioli daThe aim of this study was to analyse the antitumor effect of the Cymbopogon densiflorus essential oil in silico and in vitro on bladder cancer cells RT4 and T24, with different TP53 status. The oil was extracted by hydrodistillation and the gas chromatography coupled to the mass spectrometry was used for characterisation. In silico analysis was carried out by Pass online software. Cytotoxicity, cell proliferation, cell cycle progression, apoptosis and wound healing assays were performed. Five major compounds were identified. In silico analysis showed that major compounds present high potential for antitumor activities. The treatment with C. densiflorus essential oil reduced cell viability of bladder cancer cells. Only in wild-type cells, the increase of apoptosis rates and the decrease of cell migration were observed. In conclusion, the C. densiflorus essential oil presents antitumor effects on TP53 wild-type and mutated bladder cancer cells, however, the mechanism of action is TP53 status-dependent.Item Avaliação da atividade antioxidante e fenóis totais dos óleos extraídos das sementes de Moringa oleifera lam.(2020) Anunciação, Kamila de Fátima; Sousa, Lucas Resende Dutra; Amparo, Tatiane Roquete; Souza, Gustavo Henrique Bianco de; Vieira, Paula Melo de Abreu; Santos, Viviane Martins Rebello dos; Melo, Tânia Márcia SacramentoA Moringa oleifera Lamarck é uma planta nativa da Índia, que apresenta em suas sementes e folhas uma variedade de compostos orgânicos reconhecidos pela alta capacidade antioxidante. Este trabalho teve como objetivo avaliar a atividade antioxidante in vitro de extratos e óleos das sementes e sementes/folhas da M. oleífera Lam. Também foi determinado o teor de compostos fenólicos totais dos extratos pelo método de Folin-Ciocalteu e avaliação da citotoxicidade para fibroblastos humanos pelo método de sulforodamina B. Os resultados mostraram que o extrato etanólico da semente apresentou maior atividade antioxidante, o teor de fenólicos totais desse extrato foi de 235,11 ± 73,49 mg EAG/g e não apresentou elevada citotoxicidade nas concentrações testadas. O extrato etanólico de sementes de M. oleífera Lam possui bom potencial antioxidante e baixa citotoxicidade.Item Bioprospecção das atividades antioxidante e antimicrobiana de espécies vegetais medicinais coletadas em Ouro Preto-MG.(2013) Souza, Juliana Neves de Paula; Candotti, Julia Gesualdi; Amparo, Tatiane Roquete; Coelho, Fabiana Fioravante; Rodrigues, Ivanildes Vasconcelos; Santos, Orlando David Henrique dos; Medeiros, Luiz Fernando Teixeira de; Furtado, Niege Araçari Jacometti Cardoso; Sousa, Hildeberto Caldas de; Souza, Gustavo Henrique Bianco deO presente estudo foi realizado com os extratos etanólicos brutos de seis espécies vegetais (Bathysaaustralis, Piper corcovadensis, Siparuna brasiliensis, Picramnia sp., Piper richardiifolium, Eugenia cf. cerasiflora) de uso medicinal, coletadas na região de Ouro Preto-MG. Os extratos etanólicos foram avaliados frente à atividade antioxidante (método do DPPH) e antimicrobiana (Concentração Inibitória Mínima, CIM), bem como submetidos à dosagem de compostos fenólicos (reagente Folin-Ciocalteau) e flavonóides totais (Cloreto de Alumínio). Os resultados evidenciaram que o extrato de Siparuma brasiliensis apresentou maior atividade antioxidante (CE50 17,712 μg/mL) e o de Piper richardiifolium a melhor atividade antimicrobiana para Staphylococcus aureus (300 μg/mL) e Staphylococcus saprophyticus (200 μg/mL). Estes resultados sugerem que as atividades avaliadas estão diretamente relacionadas com a presença de compostos fenólicos, porém não necessariamente à presença de flavonoides.Item Brazilian essential oils as source for the discovery of new anti-COVID-19 drug : a review guided by in silico study.(2021) Amparo, Tatiane Roquete; Seibert, Janaína Brandão; Silveira, Benila Maria; Costa, Fernanda Senna Ferreira; Almeida, Tamires Cunha; Braga, Saulo Fehelberg Pinto; Silva, Glenda Nicioli da; Santos, Orlando David Henrique dos; Souza, Gustavo Henrique Bianco deThe emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China and its spread worldwide has become one of the biggest health problem due to the lack of knowledge about an effective chemotherapy. Based on the current reality of the SARS-CoV-2 pandemic, this study aimed to make a review literature about potential anti-coronavirus natural compounds guided by an in silico study. In the first step, essential oils from native species found in the Brazilian herbal medicine market and Brazilian species that have already shown antiviral potential were used as source for the literature search and compounds selection. Among these compounds, 184 showed high antiviral potential against rhinovirus or picornavirus by quantitative structure–activity relationship analysis. (E)-a-atlantone; 14-hydroxy-amuurolene; allo-aromadendrene epoxide; amorpha4,9-dien-2-ol; aristochene; azulenol; germacrene A; guaia-6,9-diene; hedycaryol; humulene epoxide II; aamorphene; a-cadinene; a-calacorene and a-muurolene showed by a molecular docking study the best result for four target proteins that are essential for SARS-CoV-2 lifecycle. In addition, other parameters obtained for the selected compounds indicated low toxicity and showed good probability to achieve cell permeability and be used as a drug. These results guided the second literature search which included other species in addition to native Brazilian plants. The majority presence of any of these compounds was reported for essential oils from 45 species. In view of the few studies relating essential oils and antiviral activity, this review is important for future assays against the new coronavirus.Item Cytotoxic activity of butanolic extract from Sambucus nigra L. flowers in natura and vehiculated in micelles in bladder cancer cells and fibroblasts.(2020) Pereira, Deise Inocêncio; Amparo, Tatiane Roquete; Almeida, Tamires Cunha; Costa, Fernanda Senna Ferreira; Brandão, Geraldo Célio; Santos, Orlando David Henrique dos; Silva, Glenda Nicioli da; Souza, Gustavo Henrique Bianco deBladder cancer has a high incidence and recurrence rate among patients worldwide. This study aimed to evaluate the cytotoxic activity of fractions of Sambucus nigra L. flower extracts on bladder carcinoma cells (T24 cells) and human fibroblast cells (MRC-5). The butanolic fraction (F-BuOH) was characterized by UPLC-DADMS/MS and nine flavonoids were identified. Rutin was the major compound. The cytotoxic activity of this fraction was observed in the T24 cells but not in MRC-5 cells, indicating selectivity. F-BuOH was incorporated in micellar solutions of PluronicVR F127 and cytotoxic effect for T24 cells was observed again. In vitro assay demonstrated a controlled release of the fraction from the micelles. The results obtained showed that flavonoids are the possible responsible for cytotoxic activity in bladder carcinoma cells. In addition, micellar solutions act together to increase the action of the butanolic fraction.Item Development of propolis nanoemulsion with antioxidant and antimicrobial activity for use as a potential natural preservative.(2019) Seibert, Janaína Brandão; Silva, Jessica Paola Bautista; Amparo, Tatiane Roquete; Petit, Alicia; Pervier, Pauline; Almeida, Juliana Cristina dos Santos; Azevedo, Mariana Costa; Silveira, Benila Maria; Brandão, Geraldo Célio; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Santos, Orlando David Henrique dosPropolis has demonstrated potential use as food preservative but it presents strong and unpleasant flavor that alters the sensory characteristics foods. A nanoemulsion was proposed to carry the Brazilian propolis extracts for use as natural food preservative. Antimicrobial and antioxidant activities and chemical constituents of the extracts were investigated. The latter were made by sequential extraction using different solvents (hexane, ethyl acetate and ethanol). Antimicrobial activity was evaluated by agar diffusion and microdilution methods and antioxidant activity by DPPH and ABTS assays. Extracts showed antibacterial and antioxidant activity, highlighting the ethanolic which contained artepillin-C, kaempferide, drupanin and p-coumaric acid as main compounds by LC-MS analysis. The nanoemulsion developed by phase inversion method was characterized and stable under thermal-stress and centrifugation conditions. Biological properties evaluated were effectively maintained by the formulation. It was concluded that the nanoemulsion can be used as a food preservative, preventing degradation and masking the propolis off-flavor.Item Evaluation of anti-candida albicans activity and release of ketoconazole in PMMA-G-PEG 4000 films.(2022) Reynaldo, Juliana Ribeiro; Novack, Kátia Monteiro; Sousa, Lucas Resende Dutra; Vieira, Paula Melo de Abreu; Amparo, Tatiane Roquete; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Barboza, Ana Paula Moreira; Neves, Bernardo Ruegger Almeida; Alvarenga, Meiry Edivirges; Martins, Felipe Terra; Santos, Viviane Martins Rebello dosModified release systems depend on the selection of an appropriate agent capable of controlling the release of the drug, sustaining the therapeutic action over time, and/or releasing the drug at the level of a particular tissue or target organ. Polyethylene glycol 4000 (PEG 4000) is commonly employed in drug release formulations while polymethyl methacrylate (PMMA) is non-toxic and has a good solubility in organic solvents. This study aimed at the incorporation of ketoconazole in PMMA-g-PEG 4000 and its derivatives, thus evaluating its release profile and anti-Candida albicans and cytotoxic activities. Ketoconazole was characterized and incorporated into the copolymers. The ketoconazole incorporated in the copolymer and its derivatives showed an immediate release profile. All copolymers with ketoconazole showed activity against Candida albicans and were non-toxic to human cells in the entire concentration tested.Item Evaluation of the, in vitro, photoprotetive capacity of Moringa oleifera oil for its use in sunscreen formulation.(2021) Mota, Gabriela Cristina Ferreira; Campos, Kamila de Fátima Anunciação; Sousa, Lucas Resende Dutra; Amparo, Tatiane Roquete; Vieira, Paula Melo de Abreu; Okuma, Adriana Akemi; Melo, Tânia Márcia Sacramento; Santos, Viviane Martins Rebello dosMoringa oleifera Lam is an Indian plant with applications in the agricultural and medical fields. The assets development capable of increasing the efficiency of sunscreens, mainly those of plant origin, due to their natural benefits, represents an increasing demand for cosmetology. The present study aims to identify by CG-MS the constituents of the most active oil and to evaluate the photoprotective capacity of Moringa oil, and its action in sunscreen formulations. Extracts of the oils from the Moringa seeds were evaluated for the Sun Protection Factor (SPF) observing the highest result for the dichloromethane extract. This extract showed low cytotoxic potential for human fibroblasts and it was incorporated into a sunscreen. The extract increased the SPF of the sunscreen and its effect may be related to fatty acids identified by GC-MS. The results showed the benefit of Moringa oil as a vegetable active in the sunscreen formulations by increasing the SPF of sunscreens in a natural and sustainable way.Item Green propolis : in vitro photoprotective and photostability studies of single and incorporated extracts in a sunscreen formulation.(2020) Almeida, Wanessa Aparecida da Silveira; Sousa, Lucas Resende Dutra; Antunes, Amanda dos Santos; Azevedo, Amanda Scofield de; Nascimento, Andréa Mendes do; Amparo, Tatiane Roquete; Souza, Gustavo Henrique Bianco de; Santos, Orlando David Henrique dos; Andrade, Ângela Leão; Cazati, Thiago; Vieira, Paula Melo de Abreu; Bueno, Paula Carolina Pires; Santos, Viviane Martins Rebello dosPropolis is a natural, non-toxic resin produced by honey bees that has been used for hundreds of years for its biological activities, such as antimicrobial, anti-inflammatory, anesthetic, cytostatic, and cariostatic properties. Currently, it is used in food, pharmaceutical, and cosmetic industries. The aim of this work was to evaluate the antioxidant activity, sun protection factor, and photostability of different hydroalcoholic extracts of green propolis. All extracts prepared presented high absorption in the UVB region. The extract of 70% green propolis (high temperature) was incorporated into Gel Permulen TR-1. This new formulation presented a higher value of sun protection factor. Besides that, the formulation developed with Gel Permulen TR-1 and the hydroalcoholic extract of 70% green propolis (high temperature) showed good photostability and it was safe to be applied on the skin according the HET-CAM test. These results indicated the potential of hydroalcoholic extracts of 70% green propolis (high temperature) for use in sunscreen.Item Herbal medicines to the treatment of skin and soft tissue infections : advantages of the multi‐targets action.(2019) Amparo, Tatiane Roquete; Seibert, Janaína Brandão; Vieira, Paula Melo de Abreu; Teixeira, Luiz Fernando de Medeiros; Santos, Orlando David Henrique dos; Souza, Gustavo Henrique Bianco deThe research for new treatments of skin and soft tissue infections (SSTIs) is important due to their high prevalence and number of hospitalizations. The purpose of this review is to address the pathophysiology of SSTIs to highlight the advantages of herbal medicines to their treatment, showing examples of species and compounds with multi‐targets action. SSTIs have a complex physiopathology involving the microorganism, as well as inflammation and difficult healing. Therefore, antimicrobial, anti‐inflammatory, antioxidant and healing activities are an approach possible for their treatment. Herbal medicines have a wide diversity of biological compounds, mainly phenolic compounds that may act on different targets and also have synergism between them. Therefore, a single medicine may have the four key activities that allied allow eliminating the infection, control the inflammation process and accelerating the healing process, preventing complications with chronic infections.Item In silico approach of secondary metabolites from Brazilian herbal medicines to search for potential drugs against SARS-CoV-2.(2021) Amparo, Tatiane Roquete; Seibert, Janaína Brandão; Almeida, Tamires Cunha; Costa, Fernanda Senna Ferreira; Silveira, Benila Maria; Silva, Glenda Nicioli da; Santos, Orlando David Henrique dos; Souza, Gustavo Henrique Bianco deThe new severe acute respiratory syndrome coronavirus (SARS-CoV-2) recently emerged as a worrying pandemic, with many confirmed cases and deaths globally. Therefore, there is a clear need for identifying effective therapeutic options and a review of secondary metabolites related to Brazilian herbal medicines was performed as a strategy for the discovery of new antiviral agents. To confirm this potential, an in silico screening of the identified compounds identified was also evaluated. The review was performed by the PubMed database and the selected natural compounds were subjected to in silico analysis such as QSAR, molecular docking and ADMET. 497 secondary metabolites were identified from 23 species. The in silico assays indicated 19 potential anti-SARS-CoV-2 compounds, being triterpenes and phenolic compounds. The indicated compounds showed a high affinity with proteins considered as the main molecular targets against SARS-CoV-2 and parameters indicated low toxicity. In addition to Brazilian medicinal plants, these compounds can be found in other species and they can be a base for the synthesis of other anti-COVID-19 drugs. Therefore, this review is important to conduct researches that address the emerging need for drugs in COVID-19 treatment.Item In vitro and in silico investigation of the photoprotective and antioxidant potential of Protium spruceanum leaves and its main flavonoids.(2022) Amparo, Tatiane Roquete; Silva, Anne Cherem Peixoto da; Seibert, Janaína Brandão; Silva, Débora dos Santos da; Santos, Viviane Martins Rebello dos; Vieira, Paula Melo de Abreu; Brandão, Geraldo Célio; Souza, Gustavo Henrique Bianco de; Santos, Bianca Aloise Maneira CorrêaFor the first time, the photoprotective potential (UV absorption and antioxidant properties) of Protium spru- ceanum leaves and its main flavonoids was investigated combining an in vitro and in silico approach. The extract was standardized in rutin content (0.8% w/w), quantified by a validated HPLC-DAD method. The extract pro- tected fibroblasts and keratinocytes against cell death in the stress oxidative H2O2-induced test, with greater effect than rutin standard. This cytoprotection is correlated to the free radical scavenging action, determined by DPPH method. The theoretical investigation on the UV absorption showed an excellent correlation of the results (R2 = 0.911) allowing valuable information about the photoprotective properties of rutin, afzelin and quercitrin, as the importance of the A, B and C rings in the UV absorption property and the hydroxyls in B ring (catechol group) leading to a better antioxidant action. Therefore, the extract from P. spruceanum leaves is a promising candidate for sunscreen development.Item In vitro photoprotective evaluation and development of novel nanoemulsion with chromone derivative.(2021) Antunes, Amanda dos Santos; Gouveia, Ana Paula Araújo; Diogo, Gabriela Maciel; Taylor, Jason Guy; Sousa, Lucas Resende Dutra; Amparo, Tatiane Roquete; Perasoli, Fernanda Barçante; Santos, Orlando David Henrique dos; Cazati, Thiago; Vieira, Paula Melo de Abreu; Penido, Ricardo Gonçalves; Santos, Viviane Martins Rebello dosChromone derivatives exhibiting high absorbance values in the UVA/UVB region were synthesized, and their photoprotective properties were evaluated. Chromones were prepared according to known literature procedures and characterized by high resolution mass spectrometry, infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. The in vitro solar protection factor (SPF) was determined by the Mansur method and cytotoxicity was evaluated using the sulforhodamine B assay. Two of the chromones synthesized demonstrated suitable SPF values and displayed no cytotoxic effect towards MRC-5 human fibroblasts at the tested concentrations, indicating great potential for future in vivo assays and clinical trials. Finally, the lead compound was incorporated into a nanoemulsion. Nanoemulsions showed high droplet size homogeneity and excellent stability. Chromones bearing methoxy substituents were found to be the most promising compounds with ideal photoprotective properties desirable for utilization and incorporation in sunscreen formulations.Item Melaleuca leucadendra essential oil promotes loss of cell membrane and wall integrity and inhibits bacterial growth : an in silico and in vitro approach.(2020) Silva, Jessica Paola Bautista; Seibert, Janaína Brandão; Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco de; Santos, Orlando David Henrique dosEssential oils are potential antimicrobial agents and can be used as active ingredients in the pharmaceutical, food and cosmetics industries. This work intends to evaluate the antibacterial activity and design a strategy for the proposition of the mechanism of action of Melaleuca leucadendra essential oil. Optimum concentration of the bacteria and the phase where they had the highest pathogenic activity were determined. Results show that for each microorganism it is necessary to use a diferent concentration at the time of adjusting the initial inoculum, and that the time to achieve exponential growth phase varies from one to the other. M. leucadendra essential oil demonstrated in vitro antimicrobial properties. This oil was chemically characterized and the main compounds were evaluated by their mechanism of antibacterial action based on structure–activity analysis. The mechanism is related to the increase of bacteria cell membrane permeability. This indication was confrmed by fow cytometry and transmission electronic microscopy. Thus, in silico analysis is an important tool in the search for new antimicrobial agents and these results showed that M. leucadendra essential oil may be useful on the development of new chemotherapies or food preservation systems.Item Métodos para avaliação in vitro da atividade antimicrobiana de plantas medicinais : a necessidade da padronização.(2018) Amparo, Tatiane Roquete; Braga, Vanessa Cristina de Carvalho; Seibert, Janaína Brandão; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de MedeirosA crescente incidência de patógenos resistentes aos medicamentos atuais incentiva a busca de novos agentes antimicrobianos. Neste contexto, as plantas medicinais se destacam, sendo uma importante fonte de novos fármacos. Existem diversos métodos para avaliar a atividade antibacteriana e antifúngica de extratos, frações, óleos essenciais e substâncias isoladas de vegetais. Os mais conhecidos incluem métodos de difusão, diluição e bioautografia. A proposta desse trabalho é apresentar os métodos mais utilizados atualmente, juntamente com suas vantagens, desvantagens e fatores interferentes. Entre os artigos indexados na biblioteca SciELO, abrangendo os últimos dez anos, somente 4,4% das pesquisas com plantas medicinais estão relacionadas com atividade antimicrobiana. O método mais utilizado foi a microdiluição (57,9%), o mais recomendado devido à alta sensibilidade, à quantidade mínima de reagentes e amostra e à possibilidade de um maior número de réplicas. Nos trabalhos que utilizaram esse método, foram verificadas divergências de fatores que podem interferir nos resultados. A fim de facilitar a obtenção de resultados comparáveis e reprodutíveis, destaca-se a necessidade da padronização dos métodos utilizadas pelos pesquisadores. Recomenda-se utilizar como referência as normas estabelecidas pelo CLSI para meio de cultura e concentração de inóculo nos testes. Além disso, também recomenda-se a inclusão de um controle negativo da forma de solubilização das amostras, com quantificação do crescimento microbiano, para evitar a interferência nos resultados.Item Nanostructured systems improve the antimicrobial potential of the essential oil from cymbopogon densiflorus leaves.(2019) Seibert, Janaína Brandão; Rosa, Juliana dos Santos; Almeida, Tamires Cunha; Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Lanza, Juliane Sousa; Frezard, Frederic Jean Georges; Soares, Rodrigo Dian de Oliveira Aguiar; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco de; Vieira, Paula Melo de Abreu; Barichello, José Mario; Santos, Orlando David Henrique dosThe physicochemical characteristics of nanostructured suspensions are important prerequisites for the success of new drug development. This work aimed to develop nanometric systems containing Cymbopogon densiflorus leaf essential oil and to evaluate their antimicrobial activity. The essential oil was isolated by hydrodistillation from leaves and analyzed by GC-MS. The main constituents were found to be trans-p-mentha-2,8-dien-1-ol, cis-p-mentha2,8-dien-1-ol, trans-p-mentha-1(7),8-dien-2-ol, cis-piperitol, and cis-p-mentha-1(7),8-dien-2-ol. In silico prediction analysis suggested that this oil possesses antimicrobial potential and the main mechanism of action might be the peptidoglycan glycosyltransferase inhibition. Nanoemulsions were prepared by the phase inversion method, and liposomes were made by the film hydration method. Qualitative evaluation of the antimicrobial activity was performed by the diffusion disk assay with 24 microorganisms; all of them were found to be sensitive to the essential oil. Subsequently, this property was quantified by the serial microdilution technique, where the nanoformulations demonstrated improved activity in comparison with the free oil. Bactericidal action was tested by the propidium iodide method, which revealed that free essential oil and nanoemulsion increased cytoplasmic membrane permeability, while no difference was observed between negative control and liposome. These results were confirmed by images obtained using transmission electron microscopy. This study has shown an optimization in the antimicrobial activity of C. densiflorus essential oil by a nanoemulsion and a liposomal formulation of the active substances.