Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Pharmaceutics ; 16(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38675153

RESUMO

Coumarins are benzopyrones found in several plant genera, including Pterocaulon (Asteraceae). These compounds represent an important source of new treatments, especially as antimicrobial and antifungal agents. In this study, two coumarin-rich extracts from Pterocaulon balansae using green technologies were obtained through aqueous maceration (AE) and supercritical fluid extraction (SFE). Such extracts were incorporated into nanoemulsions (NAE and NSFE) composed of a medium-chain triglyceride oil core stabilized by phospholipids. The nanoemulsions exhibited droplet sizes between 127 and 162 nm, pH above 5.0, and viscosity of approximately 1.0 cP, properties compatible with the topical route. The coumarins permeation/retention from formulations through ear porcine skin using Franz-type diffusion cells were evaluated. Whatever the extract, coumarins were distributed in skin layers, especially in the dermis in both intact and impaired (tape stripping) skin. In addition, a significant increase in coumarins that reached up to the receptor fluid was observed for impaired skin, with increases of approximately threefold for NAE and fourfold for NSFE. Finally, antifungal activity of nanoemulsions was evaluated according to minimum inhibitory concentrations, and the values were 250 µg/mL for all strains tested. The overall results demonstrated the feasibility of incorporating P. balansae extracts into nanoemulsions and showed a potential alternative for the treatment of sporotrichosis.

2.
Molecules ; 27(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35164235

RESUMO

A widely disseminated native species from Australia, Acacia mearnsii, which is mainly cultivated in Brazil and South Africa, represents a rich source of natural tannins used in the tanning process. Many flowers of the Acacia species are used as sources of compounds of interest for the cosmetic industry, such as phenolic compounds. In this study, supercritical fluid extraction was used to obtain non-volatile compounds from A. mearnsii flowers for the first time. The extract showed antimicrobial activity and the presence of p-anisic acid, a substance with industrial and pharmaceutical applications. The fractionation of the extract was performed using a chromatographic column and the fraction containing p-anisic acid presented better minimum inhibitory concentration (MIC) results than the crude extract. Thus, the extraction process was optimized to maximize the p-anisic acid extraction. The response surface methodology and the Box-Behnken design was used to evaluate the pressure, temperature, the cosolvent, and the influence of the particle size on the extraction process. After the optimization process, the p-anisic acid yield was 2.51% w/w and the extraction curve was plotted as a function of time. The simulation of the extraction process was performed using the three models available in the literature.


Assuntos
Acacia/química , Bactérias/efeitos dos fármacos , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/normas , Etanol/química , Éteres de Hidroxibenzoatos/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Flores/química , Éteres de Hidroxibenzoatos/isolamento & purificação , Modelos Teóricos , Extratos Vegetais/isolamento & purificação
3.
Braz. arch. biol. technol ; 63: e20190213, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132272

RESUMO

Abstract This study aims to find the best conditions for the extraction of Zingiber officinale essential oil using the supercritical fluid extraction (SFE), steam distillation (SD) and hydrodistillation (HD) techniques, regarding the maximum oil yield. For the HD technique is evaluated the best ratio between plant mass and water volume and for SFE and SD the pressure condition was investigated. Principal Component Analysis (PCA) was used to evaluate the similarity between the composition of the essential oil in different pressures and extraction methods. The experimental extraction curve was plotted and three different mathematical models were used to fit the data for SD and SFE methods, obtaining the relevant mass transfer parameters. The essential oil compounds were identified by gas chromatography coupled with mass spectrometry (GC-MS), being α-zingiberene the main component with different contents (from 11.9 to 28.9%). The best condition for the SFE was 100 bar, 40 °C (0.0508 goil/gplant) with 19.34% of α-zingiberene; for the SD, 3 bar (133 °C) (0.00616 goil/gplant) with 28.9% of α-zingiberene; and HD, the volume of 750 mL (0.006988 goil/gplant) with 15.70% of α-zingiberene, all measured on a dry basis.


Assuntos
Óleos Voláteis/isolamento & purificação , Zingiber officinale/química , Destilação , Cromatografia com Fluido Supercrítico , Cromatografia Gasosa-Espectrometria de Massas , Modelos Teóricos
4.
Curr Drug Discov Technol ; 16(1): 96-103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29962347

RESUMO

BACKGROUND: Species of Valeriana show sedative, hypnotic, anxiolytic, antidepressant and anti-inflammatory properties, which are associated with valepotriates. However, data about toxicity and safety of these compounds are still limited. The aim of this study was to investigate the toxicity of a valepotriate-enriched fraction (VAL) from Valeriana glechomifolia Meyer based on the Organization for Economic Cooperation and Development (OECD) guidelines 423 and 407. METHODS: In the acute study, CF1 mice were treated with a single dose of VAL (2000 mg/kg, p.o.) and observed for 14 days. In the repeated dose study, CF1 mice received single daily doses of VAL (30, 150 or 300 mg/kg, p.o.) or vehicle for 28 days. These doses were chosen based on previous results by our group and according to Guideline 407- OECD. RESULTS: The acute study allowed to classify VAL in the hazard category 5. The repeat-dose study has shown that VAL 300 mg/kg delayed weight gain and reduced food consumption in the first week, probably due to transient sedative effects. The other doses had no effect on animals' ponderal evolution. At the end of the treatment, all groups had equal body weight and food consumption. None of the doses altered any behavioral, urinary, biochemical, hematological, anatomic or histological parameters. CONCLUSION: A valepotriate-enriched fraction from Valeriana glechomifolia presents relatively low oral acute toxicity and does not induce evident toxicity after oral repeated treatment (at least up to 300 mg/kg) in mice.


Assuntos
Iridoides/toxicidade , Extratos Vegetais/toxicidade , Valeriana , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Camundongos , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
5.
Braz. arch. biol. technol ; 56(3): 513-519, May-June 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-679199

RESUMO

This work investigates the antimicrobial activity of the Schinus molle L. leaves extracts obtained under supercritical conditions using carbon dioxide and co-solvents. Antimicrobial qualitative evaluation was carried out through the bioautography technique and the microorganisms studied were Staphylococcus aureus, Pseudomonas aeruginosas, Escherichia coli, Micrococcus luteus, and Salmonella choleraesuis. The supercritical fluid extraction was carried out in a pilot scale equipment using carbon dioxide modified by the addition of co-solvents, such as ethanol and water at 150 bar and 333 K. A mathematical modeling of the process was also performed.

6.
Parasitol Int ; 62(2): 112-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23142570

RESUMO

The anti-Trichomonas vaginalis activity of Hypericum polyanthemum extract obtained by supercritical fluid extraction (50°C, 150bar) and the chemical compounds isolated and purified from this extract (benzopyrans HP1, HP2, HP3, and phloroglucinol derivative uliginosin B) were assessed. All samples had anti-T. vaginalis activity; however, HP1 demonstrated the best selectivity against this protozoan (metronidazole-resistant and susceptible isolates), with no cytotoxicity on mammalian cells (selectivity index of 73.97). Moreover, HP1 had activity against a metronidazole-resistant isolate (52% of viable trophozoites), and this effect was higher when tested with a low concentration of metronidazole (23% of viable trophozoites). Experiments demonstrated that all isolated compounds caused damage to the parasites' membrane (>90% of LDH release) and do not present a notable hemolytic effect, although HP2 and uliginosin B exhibited cytotoxicity against mammalian cells. Therefore, the analyzed molecules are promising prototypes for new antiprotozoal drugs, especially HP1, which seems to improve metronidazole's effect on a resistant T. vaginalis isolate.


Assuntos
Antiprotozoários/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Hypericum/química , Extratos Vegetais/farmacologia , Trichomonas vaginalis/efeitos dos fármacos , Animais , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Benzopiranos/química , Benzopiranos/isolamento & purificação , Benzopiranos/farmacologia , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular , Chlorocebus aethiops , L-Lactato Desidrogenase/metabolismo , Metronidazol/farmacologia , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proteínas de Protozoários/metabolismo , Trichomonas vaginalis/enzimologia , Trichomonas vaginalis/fisiologia , Células Vero
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...