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1.
Braz J Microbiol ; 54(4): 2663-2670, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37684539

RESUMO

R-(+)-Perillic acid, a promising anticancer and immunomodulatory agent, is the major product from the biotransformation of R-(+)-limonene-rich orange essential oil by the yeast Yarrowia lipolytica. Due to the abundance and low cost of orange essential oil, which is a byproduct of the citrus industry, we attempted to improve the biotransformation process by optimizing yeast cell mass production. Then, the whole process was transposed and adapted to a 2-L instrumented bioreactor. Cell mass production was optimized in shaker flasks using a statistical experimental design. The optimized medium (g·L-1: 22.9 glucose, 7.7 peptone, 4.1 yeast extract and 1.0 malt extract) resulted in a 13.0 g·L-1 final cell concentration and 0.18 g cell·L-1·h-1 productivity. A further increase to 18.0 g·L-1 was achieved in a 2-L bioreactor upon fed-batch culture. High-purity limonene bioconversion was performed in the same bioreactor utilizing top aeration to diminish terpene volatilization; as a result, 839.6 mg·L-1 perillic acid accumulated after 48 h. Under the same conditions, industrial orange essential oil afforded 806.4 mg·L-1 perillic acid. The yeast growth medium optimization resulted in a twofold increase in biomass accumulation and a reduction in growth medium nitrogen sources, which lowered the catalytic biomass production cost. Compared with conventional bottom aeration, the bioreactor top aeration strategy resulted in higher bioconversion rates. The conditions developed for high-purity limonene bioconversion were successfully applied to low-cost orange essential oil, showing the robustness of Y. lipolytica yeast.


Assuntos
Óleos Voláteis , Yarrowia , Yarrowia/metabolismo , Limoneno/metabolismo , Reatores Biológicos/microbiologia
2.
J Ethnopharmacol ; 259: 112981, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32442591

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leishmaniasis is a neglected disease that affects millions of people around the world. Parasite resistance and the toxicity to the current treatments lead to the search for new effective molecules. Plants are widely used in traditional and indigenous medicine to treat different diseases. The oleoresin of the genus Protium, which is rich in volatile compounds active against different microorganisms, is among these plants. AIM: The aim of this study was to evaluate the leishmanicidal potential of Protium altsonii (PaEO) and P. hebetatum (PhEO) (Burseraceae) oleoresins, as well as of three representative monoterpenes in their constitution: α-pinene, p-cymene and 1,8-cineole. MATERIALS AND METHODS: Protium altsonii (PaEO) and P. hebetatum (PhEO) oleoresins and three of their constituents were tested in vitro on promastigotes and amastigotes-infected macrophages in different concentrations. Their toxicity for macrophages was analyzed by XTT assay and phagocytic ability. It was evaluated the ability of the compounds to induce NO production on treated-macrophages using Griess reaction and the effect of them in lipid profile on treated-parasite through Thin Layer Chromatography. RESULTS: Our data showed that both essential oils have toxic effect on promastigotes and amastigotes of L. amazonensis in vitro in a dose-dependent manner. PaEO IC50 were 14.8 µg/mL and 7.8 µg/mL and PhEO IC50s were 0.46 µg/mL and 30.5 µg/m for promastigotes and amastigotes, respectively. Toxicity to macrophages was not observed at 50 µg/mL with both EOs. The compounds 1,8- cineole, α-pinene, and p-cymene inhibited amastigotes survival in a dose-dependent manner with IC50s of 48.4 µg/mL, 37 µg/mL, 46 µg/mL, respectively. Macrophage viability was around 90% even at 200 µg/mL and the phagocytic capacity was not altered in the treated-macrophages to up 50 µg/mL. The compounds were not able to modulate the nitric oxide production either at rest or LPS-activated macrophages. In addition, treated promastigote revealed an important change in their lipid profile after 48 h at 50 µg/mL in the presence of the compounds. CONCLUSIONS: The results indicate that oleoresins of Protium genus are potent against Leishmania and α-pinene, p-cymene and 1,8-cineole have anti-Leishmania properties that could be explored in synergistic assays in order to develop new drug candidates.


Assuntos
Antiprotozoários/farmacologia , Burseraceae , Leishmania mexicana/efeitos dos fármacos , Macrófagos/parasitologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Animais , Antiprotozoários/isolamento & purificação , Burseraceae/química , Burseraceae/classificação , Células Cultivadas , Relação Dose-Resposta a Droga , Leishmania mexicana/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Monoterpenos/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Carga Parasitária , Testes de Sensibilidade Parasitária , Óleos de Plantas/isolamento & purificação
3.
Vigil. sanit. debate ; 6(2): 7-17, maio 2018.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-916405

RESUMO

Introdução: O presente estudo descreve a aplicação da ferramenta de gerenciamento de riscos Análise de Modo e Efeito de Falha (Failure Mode Effects Analysis ­ FMEA) a uma pesquisa clínica que estabelecerá um tratamento de indivíduos simultaneamente infectados por HIV e tuberculose. Objetivo: Demonstrar a importância da análise de riscos associada aos protocolos de estudos clínicos na salvaguarda do participante e dos dados do estudo, e como padrão de qualidade do estudo. Método: Os procedimentos demandados na execução do protocolo clínico e os potenciais modos de falha a eles associados foram estipulados com base na programação de visitas do participante ao centro do estudo. Os modos de falha foram valorados entre 1 e 10 de acordo com: Gravidade, Ocorrência e Detectabilidade, calculando-se o Número de Prioridade de Risco (NPR) pela multiplicação dos três valores. Resultados: Num painel de 25 procedimentos e 60 modos de falha, 50% resultaram em NPR > 120; seis deles contendo mais de cinco modos de falha. Os maiores riscos foram associados à estratégia DOT (NPR 294), à coleta de sangue (NPR 288), ao Termo de Consentimento Livre e Esclarecido (NPR 270) e a coletas de dados do participante (NPR 240). Conclusões: Os resultados demonstraram a importância da FMEA como instrumento de avaliação de riscos em estudos clínicos, alinhando-se com recomendações de órgãos normalizadores internacionais.


Introduction: This study describes the application of the Failure Mode and Effects Analysis (FMEA) as a tool for risk management during clinical research to establish the treatment of patients simultaneously infected with HIV and tuberculosis. Objective: To demonstrate the importance of risk analysis associated with clinical trial protocols in safeguarding the participant and study data, and as a study's quality standard. Method: Procedures demanded by the clinical protocol were detailed and then associated with failure modes based on the programmed visits of the participant to the study center. The failure modes were rated between 1 and 10 according to: Severity, Occurrence and Detectability, and the Risk Priority Number (RPN) was calculated by multiplying the three values. Results: In a panel of 25 procedures and 60 failure modes, 50% resulted in RPN > 120; six of which contained more than five failure modes. The highest risks were associated with the DOT strategy (RPN 294), blood collection (RPN 288), the Informed Consent Term (RPN 270) and participant data collection (RPN 240). Conclusions: The results demonstrate the importance of FMEA as a tool to assess risks in clinical studies, in line with the recommendations of international standardization organizations.

4.
Parasitology ; 145(9): 1219-1227, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29352826

RESUMO

Leishmaniases is a tropical disease caused by protozoa of the genus Leishmania for which the current treatment is expensive, besides increasing reports of parasite resistance. This study investigated the anti-Leishmania amazonensis activity of the essential oil from Aloysia gratissima (AgEO) and guaiol, the major sesquiterpene constituent in the oil. Our results showed that AgEO killed promastigotes and intracellular amastigotes at an IC50 of 25 and 0·16 µg mL-1, respectively, while guaiol killed amastigotes at an IC50 of 0·01 µg mL-1. Both AgEO and guaiol were safe for macrophages up to 100 µg mL-1, as evaluated by the dehydrogenase activity, membrane integrity and phagocytic capacity. AgEO and guaiol did not induce nitrite oxide (NO) in resting macrophages and inhibited the production of NO in lipopolysaccharide-stimulated macrophages. The ultrastructural analysis suggested that AgEO and guaiol act directly on parasites, affecting promastigotes kinetoplast, mitochondrial matrix and plasma membrane. Together, these results pointed out that AgEO and guaiol could be promising candidates to develop anti-Leishmania drugs.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Animais , Células Cultivadas , Concentração Inibidora 50 , Estágios do Ciclo de Vida , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Sesquiterpenos de Guaiano
5.
Mem. Inst. Oswaldo Cruz ; 112(6): 458-468, June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841802

RESUMO

ABSTRACT BACKGROUND Dengue fever may present hemorrhages and cavitary effusions as result of exacerbated immune responses. We investigated hydro-alcoholic extracts from leaves (UGL) and bark (UGB) of the medicinal species Uncaria guinanensis with respect to antiviral effects in Dengue virus (DENV) infection and in immunological parameters associated with in vivo physiopathological features. METHODS Chemical profiles from UGB or UGL were compared in thin layer chromatography and 1H nuclear magnetic resonance using flavonoid compounds and a pentacyclic oxindole alkaloid-enriched fraction as references. DENV-2-infected hepatocytes (Huh-7) were treated with extracts. Cell viability, DENV antigens and immunological factors were detected by enzyme-linked immunosorbent assay (ELISA) or flow cytometry. FINDINGS The UGL mainly differed from UGB by selectively containing the flavonoid kaempferitrin. UGB and UGL improved hepatocyte viability. Both extracts reduced intracellular viral antigen and inhibited the secretion of viral non-structural protein (NS1), which is indicative of viral replication. Reduction in secretion of macrophage migration inhibitory factor was achieved by UGB, of interleukin-6 by UGL, and of interleukin-8 by both UGB and UGL. MAIN CONCLUSIONS The U. guianensis extracts presented, antiviral and immunomodulatory effects for DENV and possibly a hepatocyte-protective activity. Further studies may be performed to consider these products as potential candidates for the development of an herbal product for the future treatment of dengue.


Assuntos
Humanos , Antivirais/farmacologia , Extratos Vegetais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Citocinas/imunologia , Quimiocinas/efeitos dos fármacos , Quimiocinas/imunologia , Uncaria/química , Dengue/fisiopatologia , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/efeitos dos fármacos , Vírus da Dengue/imunologia , Antígenos Virais/efeitos dos fármacos , Antígenos Virais/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo
6.
Pharmacogn Mag ; 11(43): 470-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26246721

RESUMO

BACKGROUND: Triterpenes as betulinic (BA), oleanolic (OA) and ursolic acids (UA) have increasingly gained therapeutic relevance due to their wide scope of pharmacological activities. To fit large-scale demands, exploitable sources of these compounds have to be found and simple, cost-effective methods to extract them developed. Leaf material represents the best plant sustainable raw material. To obtain triterpene acid-rich extracts from leaves of Eugenia, Psidium and Syzygium species (Myrtaceae) by directly treating the dry plant material with alkalinized hydrated ethanol. This procedure was adapted from earlier methods to effect depolymerization of the leaf cutin. MATERIALS AND METHODS: Extracts were prepared by shaking the milled dry leaves in freshly prepared 2% NaOH in 95% EtOH solution (1:4 w/v) at room temperature for 6 h. Working up the product in acidic aqueous medium led to clear precipitates in which BA, OA and UA were quantified by gas chromatography. RESULTS: Pigment-free and low-polyphenol content extracts (1.2-2.8%) containing 6-50% of total triterpene acids were obtained for the six species assayed. UA (7-20%) predominated in most extracts, but BA preponderated in Eugenia florida (39%). Carried out in parallel, n-hexane defatted leaves led to up to 9% enhancement of total acids in the extracts. The hydroalcoholate treatment of Myrtaceae species dry leaves proved to be a cost-effective and environmentally friendly method to obtain triterpene acids, providing them be resistant to alkaline medium. These combined techniques might be applicable to other plant species and tissues.

7.
J Pharm Biomed Anal ; 48(4): 1090-5, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18845411

RESUMO

Carapa guianensis crabwood, popularly known in Brazil as "andiroba", is a tree that grows in South and Central America and is used by the local population mainly for its anti-inflammatory and insect anti-feeding activities. Scientific studies on this plant have led to the development of an insect-repellent candle and the investigations of the anti-inflammatory properties of its more important biomarkers-tetranortriterpenoids. These compounds, together with glycerides and fatty acids, are present in the seed oil, the most important commercial product from this plant. The growing scientific and commercial interest in "andiroba oil" has urged the development of adequate analytical methods for assessing its quality. Central composite experimental design is a useful statistical method for the development and optimization of HPLC methods, and has been used for a variety of samples. The aim of this work is to develop a HPLC method for the determination of tetranortriterpenoids in "andiroba" oil, by means of central composite experimental design, as well as to prevalidate this method.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Limoninas/análise , Meliaceae/química , Óleos de Plantas/química , Projetos de Pesquisa , Sementes/química , Calibragem , Limoninas/química , Limoninas/isolamento & purificação , Estrutura Molecular , Reprodutibilidade dos Testes
8.
Hist. ciênc. saúde-Manguinhos ; 15(1): 29-46, jan.-mar. 2008.
Artigo em Inglês, Português | LILACS, HANSEN, Hanseníase | ID: lil-480726

RESUMO

Analisa os processos de assimilação e transformação de saberes e práticas terapêuticas que envolvem o uso de plantas medicinais, e destaca o uso, no combate à lepra, do óleo da chaulmoogra. Atenta para os diferentes modos de incorporação e transformação das chaulmoogras em conhecimentos validados cientificamente, tendo em vista a entrada em cena da 'chaulmoogra brasileira'. Privilegia a chegada dos derivados dessa planta à pauta de produção do Instituto Oswaldo Cruz (IOC), na década de 1920, estabelecendo nexos entre os diferentes processos produtivos e articulando-os ao contexto científico no período estudado. O óleo de chaulmoogra representou, até a década de 1940, a grande esperança para a tentativa de cura da lepra. Observa ainda que a terapêutica chaulmúgrica durante esse período, consolidou-se como um saber científico graças à realização de diversas pesquisas feitas em laboratórios de todo o mundo ocidental.


The article investigates how knowledge of medicinal plants and related treatment practices are assimilated and transformed. Taking as its focus the use of chaulmoogra oil to treat leprosy, it examines how information on this plant was incorporated and transformed into scientifically validated knowledge when 'Brazilian chaulmoogra' came onto the scene. Pointing to the addition of chaulmoogra byproducts to the Instituto Oswaldo Cruz's production agenda in the 1920s, the study establishes links between productive processes and relates these to the period's scientific context. From the late nineteenth century until the 1940s, chaulmoogra oil was the great hope in efforts to cure leprosy. During this period, chaulmoogric treatment earned a place as scientific knowledge thanks to research studies conducted in laboratories throughout the Western world.


Assuntos
Chaulmoogra/uso terapêutico , Hanseníase/terapia , Óleos de Plantas/uso terapêutico , Brasil , História da Medicina , Plantas Medicinais
9.
Hist Cienc Saude Manguinhos ; 15(1): 29-47, 2008.
Artigo em Português | MEDLINE | ID: mdl-19241672

RESUMO

The article investigates how knowledge of medicinal plants and related treatment practices are assimilated and transformed. Taking as its focus the use of chaulmoogra oil to treat leprosy, it examines how information on this plant was incorporated and transformed into scientifically validated knowledge when 'Brazilian chaulmoogra' came onto the scene. Pointing to the addition of chaulmoogra byproducts to the Instituto Oswaldo Cruz's production agenda in the 1920s, the study establishes links between productive processes and relates these to the period's scientific context. From the late nineteenth century until the 1940s, chaulmoogra oil was the great hope in efforts to cure leprosy. During this period, chaulmoogric treatment earned a place as scientific knowledge thanks to research studies conducted in laboratories throughout the Western world.


Assuntos
Hansenostáticos/história , Hanseníase/história , Fitoterapia/história , Óleos de Plantas/história , História do Século XIX , História do Século XX , Humanos , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Extratos Vegetais/história , Extratos Vegetais/uso terapêutico , Óleos de Plantas/uso terapêutico , Plantas Medicinais
10.
Rev. adm. pública ; 40(3): 457-478, maio-jun. 2006. ilus
Artigo em Português | LILACS | ID: lil-442034

RESUMO

As atividades de pesquisa e desenvolvimento (P&D) realizadas nos institutos públicos de pesquisa (IPPs) têm como característica uma gestão arraigada nas premissas acadêmicas, que priorizam a geração e difusão do conhecimento. Em contrapartida, a necessidade de competitividade tecnológica no mercado e a pressão pela participação, como instrumentos da política pública do esforço nacional rumo à inovação, têm pressionado os IPPs para a busca por resultados mais concretos. Esse fato acarreta a geração de grandes lacunas nos processos relacionados à gestão, induzindo a uma constante necessidade de aperfeiçoamento gerencial, no sentido de criar e melhorar ferramentas que contribuam para adequá-la à nova realidade. Este artigo propõe uma metodologia de gestão de projetos de P&D, que se baseia no direcionamento dos projetos de pesquisa para a obtenção de produtos, e considera suas características multidisciplinares e interdisciplinares e a incerteza inerentes a esse processo. Essa metodologia foi desenvolvida no Instituto de Tecnologia de Fármacos da Fiocruz e é proposta como um modelo original para instituições semelhantes.


Assuntos
Métodos , Organização e Administração , Projetos de Pesquisa
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