RESUMO
UNLABELLED: The in vitro activity of the imidazolium salt C16 MImCl against planktonic and biofilm cells of multidrug-resistant isolates of Candida tropicalis was evaluated, both in solution and applied on a commercial catheter surface. This was determined by inhibition and susceptibility assays of biofilm and planktonic cells. In both cases, C16 MImCl prevented in vitro biofilm formation of C. tropicalis strains, including multidrug-resistant ones. Outstanding performances were observed, even at extremely low concentrations. Furthermore, this is the first report of the antifungal lock property of C16 MImCl, using a tracheal catheter as the test specimen to mimic a clinical in vivo condition. As such, C16 MImCl has been identified as a promising antimicotic pharmaceutical candidate for the treatment of candidiasis infections. SIGNIFICANCE AND IMPACT OF THE STUDY: The imidazolium salt 1-n-hexadecyl-3-methylimidazolium chloride (C16 MImCl) strongly prevents, in concentrations as low as 0·028 µg ml(-1) , the biofilm formation of multidrug-resistant Candida tropicalis isolates, either in solution or applied on the surface of commercial catheters. This presents an effective antimicotic candidate and alternative for invasive clinical procedure toolset asepsis.
Assuntos
Antifúngicos/farmacologia , Candida tropicalis/efeitos dos fármacos , Imidazóis/farmacologia , Biofilmes/efeitos dos fármacos , Candida tropicalis/isolamento & purificação , Candida tropicalis/fisiologia , Candidíase/microbiologia , Farmacorresistência Fúngica Múltipla , Humanos , Testes de Sensibilidade Microbiana , Plâncton/efeitos dos fármacosRESUMO
Entire seeds of Chenopodium quinoa Willd are a rich protein source and are also well-known for their high saponin content. Due to their amphiphily quinoa saponins are able to form intricate micellar aggregates in aqueous media. In this paper we study the aggregates formed by self-association of these compounds from two quinoa saponin fractions (FQ70 and FQ90) as well as several distinctive nanostructures obtained after their complexation with different ratios of cholesterol (CHOL) and phosphatidylcholine (PC). The FQ70 and FQ90 fractions were obtained by reversed-phase preparative chromatography. The structural features of their resulting aggregates were determined by Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM). Novel nanosized spherical vesicles formed by self-association with mean diameter about 100-200 nm were observed in FQ70 aqueous solutions whereas worm-like micelles an approximate width of 20 nm were detected in FQ90 aqueous solutions. Under experimental conditions similar to those reported for the preparation of Quillaja saponaria ISCOM matrices, tubular and ring-like micelles arose from FQ70:CHOL:PC and FQ90:CHOL:PC formulations, respectively. However, under these conditions no cage-like ISCOM matrices were observed. The saponin composition of FQ70 and FQ90 seems to determine the nanosized structures viewed by TEM. Phytolaccagenic acid, predominant in FQ70 and FQ90 fractions, is accountable for the formation of the nanosized vesicles and tubular structures observed by TEM in the aqueous solutions of both samples. Conversely, ring-like micelles observed in FQ90:CHOL:PC complexes can be attributed to the presence of less polar saponins present in FQ90, in particular those derived from oleanolic acid.
Assuntos
Chenopodium quinoa/química , Saponinas/análise , Química Farmacêutica , Colesterol/química , Luz , Micelas , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Fosfolipídeos/química , Extratos Vegetais/química , Espalhamento de Radiação , Soluções , ÁguaRESUMO
The spectrophotometric assay based on aluminum chloride complex formation is one of the most commonly analytical procedures applied to flavonoid content determination. However, only a few optimization studies on the reaction conditions were done so far. The present work aims to the investigation of aluminum chloride concentration and reaction time effects on the spectrophotometric behavior of different flavonoids. The effects of both variation factors were studied by Central Composite Design and Response Surface Analysis methodology. The absorption data analysis showed that the effects of reaction time and reagent concentration on the absorption maximum are intricate and specific. A clear relationship between spectrophotometric behavior and flavonoid type or particular structure patterns could not be established.
Assuntos
Flavonoides/análise , Cloreto de Alumínio , Compostos de Alumínio , Cloretos , Indicadores e Reagentes , Modelos Teóricos , Reprodutibilidade dos Testes , Espectrofotometria UltravioletaRESUMO
Several species of the genus Passiflora, known in Brazil as "maracujá", have widespread use in folk medicine as sedatives and tranquillizers. The anxiolytic activity of hydroethanol extracts of P. alata and P. edulis leaves was evaluated using the elevated plus-maze test. The extracts presented anxiolytic activity in dosages around 50, 100 and 150 mg/kg.
Assuntos
Ansiolíticos/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Plantas Medicinais , Rosales , Animais , Relação Dose-Resposta a Droga , Masculino , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos , Ratos WistarRESUMO
This work relates to the formulation of tablets containing a high proportion of spray-dried extracts (SDEs) from Passiflora edulis leaves. The tablets were prepared by direct compression. Colloidal silicon dioxide was selected as a glidant and moisture adsorbent, cross-linked carboxymethycellulose was used as the disintegrant, microcrystalline cellulose was the filler/binder, and tricalcium phosphate as a spray-drying adjuvant. The colloidal silicon dioxide and cross-linked carboxymethycellulose quantities and their influences on the tablet hardness and disintegration time were studied by a central composite design. The model equations were fitted to the experimental data and then validated. It could be concluded that the colloidal silicon dioxide proportion increased the hardness, and the cross-linked carboxymethycellulose proportion determined a linear decrease of the disintegration time. The optimal values chosen were 2.0% Aerosil 200 and 2.5% Ac-Di-Sol. The tablets showed a hardness of 85.02 N and a disintegration time of 7.35 min.
Assuntos
Química Farmacêutica , Extratos Vegetais , Coloides , Dióxido de Silício/química , Comprimidos/químicaRESUMO
Passiflora edulis (passionflower) is a plant widely used in the Brazilian popular medicine and phytopharmaceutical industry for its sedative activity. This work refers to the development of spray-dried powders (SDPs) from the 40% ethanolic extractive solution of P. edulis aerial parts. The SDPs were prepared with a Büchi 190 Mini-spray dryer using as drying adjuvants Aerosil 200 alone (SDP1), an Aerosil 200: Gelita-Sol-P (1:1) mixture (SDP2) and an Aerosil 200:Gelita-Sol-P (1:3) mixture (SDP3). All the powders were obtained using 40 parts adjuvant and 60 parts extract dried residue. The comparison criteria applied were particle size distribution, hygroscopicity at 95%, 60%, and 35% relative humidity (RH), as well as the flavonoid process recovery. The particle size distributions were analyzed by way of (a) normal distribution parameters, (b) the RRSB grid and (c) considering diameter values in terms of an equivalent sphere. All the powders presented nonnormal distribution, and the RRSB analysis appeared to be, therefore, the analysis method of choice. The total flavonoid recovery was around 80%, and it was practically not affected by the SDP1, SDP2, and SDP3 compositions. At the 60% and 90% RH atmospheres, the SDP3 and SDP2 moisture uptakes were higher than that of the SDP1. All the formulations were, on the contrary, stable at 35% RH, showing a slight moisture loss tendency. The results showed in sum that the SDP prepared using Aerosil 200 as the drying adjuvant alone presented the best technological characteristics of all.
Assuntos
Adjuvantes Farmacêuticos , Plantas Medicinais , Pós , Aerossóis/química , Química Farmacêutica , Flavinas/análise , Tamanho da PartículaRESUMO
Achyrocline satureioides spray-dried extracts, prepared with colloidal silicon dioxide, microcrystalline cellulose + colloidal silicon dioxide (1:1), and beta-cyclodextrin + colloidal silicon dioxide (1:1), were incorporated in a glyceryl monostearate base. The influence of the spray-drying adjuvants on the formulations' physical characteristics, such as spreading properties, oil indexes, viscosities, and the pH determination, were evaluated. The results indicated that the adjuvants influenced the ointments' physical parameters at different levels, although all of them maintained their plastic flow and presented antithixotropic behavior. The presence of colloidal silicon dioxide alone, in the dried extract, imparted the lowest oil index value and an intermediary spreading area to the ointment. The colloidal silicon dioxide content reduction and the substitution of part of it by beta-cyclodextrin or microcrystalline cellulose enhanced the ointments' oil index values, while the best spreading area was reached by the ointment prepared with the spray-dried extract containing colloidal silicon dioxide and microcrystalline cellulose.
Assuntos
Plantas Medicinais/química , beta-Ciclodextrinas , Coloides , Ciclodextrinas , Excipientes , Glicerídeos , Concentração de Íons de Hidrogênio , Pomadas , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Dióxido de Silício , ViscosidadeRESUMO
The studies in relation to rhino-bronchial syndrome are very few. That's true because of the diagnosis and treatment of the specimens is not made in a randomized way. And because of the many different etiology. In this paper two hundred and thirty files were studied within the diagnosis of RBS among patients consulting in the Pediatric Allergy Service in 1989. The results show that this process is multifactorial: allergic 72%, infections 23% and functional (gastric reflux) in 4%. There was improvement with specific treatment with immunotherapy and general measurements in 82%. Since fourth month of treatment.