Estruturação de emulsão tipo maionese com característica funcional e produzida com derivado proteico / Mayonnaise emulsion with functional characteristic and produced with protein derivative

O soro de leite é considerado um subproduto das indústrias de laticínios, uma parte de sua produção é destinada como matéria-prima de produtos alimentícios, mas parte é direcionada para alimentação animal. Objetivou-se com o presente estudo elaborar formulas de emulsões do tipo maionese utilizando ingrediente proteico o soro de leite em pó, leite desnatado em pó e a mistura entre soro e leite, ambos em pó, bem como investigar a influência destes ingredientes na textura, reologia, análise térmica, índice de estabilidade, análise colorimétrica e a vida útil das formulações. Justifica-se a utilização de soro de leite devido a seu menor preço de mercado do que ovos em pó ou líquido pasteurizado normalmente utilizados, evidenciando a necessidade de dar espaço a matérias-primas consideradas como subprodutos dentro da indústria. Os produtos emulsionados foram formulados com mistura de óleo, água, soro de leite em pó, leite desnatado em pó, alho e mostarda em pó, contendo aproximadamente 70% de gordura, com variação no teor proteico. Foram estabelecidas três formulações cada uma com um tipo ou mistura de emulsificantes. As análises efetuadas no desenvolvimento do trabalho foram textura, reologia, atividade de água, pH, colorimetria, análise térmica, índice de estabilidade da emulsão e cálculo de proteínas e lipídeos das formulações. Foi possível verificar que tanto o soro de leite em pó como o leite desnatado em pó apresentaram características de agente emulsificante.A formulação F1 (soro de leite em pó) não atingiram os padrões estruturais de maioneses comerciais, todavia os resultados obtidos pela formulação F2 (leite desnatado em pó) atingiram padrões equivalentes a produtos comercializados, bem como a formulação F3 (soro de leite em pó + leite desnatado em pó) com padrão das maioneses light em textura e reologia. Os resultados das análises de atividade de água apresentaram pequenas variações (0,934-0,941) ao longo dos 30 dias de avaliação. Os conservantes em pó (alho e mostarda) favoreceram a coloração das formulações, pH na faixa da neutralidade, assegurando aos produtos vida útil de 30 dias em temperatura de refrigeração. É possível utilizar osoro de leite e leite em pó como agente emulsificante para emulsões do tipo maionese, bem como alho e mostarda em pó como ingredientes que aumentem a maior vida útil desses produtos

Whey is considered a by-product of the dairy industry, part of its production is used as raw material for food products, but part is used for animal feed. The objective of this study was to prepare mayonnaise emulsion formulas using protein whey powder, skimmed milk powder and the mixture between whey and milk, both in powder, as well as investigating the influence of these ingredients on texture, rheology, thermal analysis, stability index, colorimetric analysis and the useful life of the formulations. The use of whey is justified due to its lower market price than powdered eggs or pasteurized liquid normally used, highlighting the need to make room for raw materials considered as by-products within the industry. The emulsified products were formulated with a mixture of oil, water, whey powder, skimmed milk powder, garlic and mustard powder, containing approximately 70% fat, with variation in protein content. Three formulations were established each with a type or mixture of emulsifiers. The analyzes carried out in the development of the work were texture, rheology, water activity, pH, colorimetry, thermal analysis, emulsion stability index and calculation of proteins and lipids in the formulations. It was possible to verify that both whey powder and skimmed milk powder showed characteristics of emulsifying agent. Formulation F1 (whey powder) did not reach the structural standards of commercial mayonnaise, however the results obtained by formulation F2 (skimmed milk powder) reached standards equivalent to commercialized products, as well as the formulation F3 (whey powder + skimmed milk powder) with light mayonnaise pattern in texture and rheology. The results of the water activity analysis showed slight variations (0.934-0.941) over the 30 days of evaluation. The preservatives in powder (garlic and mustard) favored the color of the formulations, pH in the neutrality range, ensuring the products' useful life of 30 days in refrigeration temperature. It is possible to use whey and powdered milk as an emulsifying agent for emulsions of the mayonnaise type, as well as garlic and mustard powder as ingredients that increase the longer useful life of these products

Biosurfactant and bioemulsifier as promising molecules produced by Mucor hiemalis isolated from Caatinga soil

BACKGROUND: The present study describes the production of biosurfactant (BS) and emulsifier (BE) by the filamentous fungus Mucor hiemalis UCP 0039, as well as the characterization and stability of the both biomolecules for environmental or industrial applications. RESULTS: Biosurfactants and bioemulsifiers are amphiphilic compounds and are produced as extracellular molecules. The results showed that bioproduct obtained by shaker condition reduced the water surface tension of 72 to 32 mN/m and reached an emulsification index of 96%, while the static cultivation resulted in a biomolecule with a surface tension of 40 mN/m and an emulsification index of 96%, suggesting the production of a biosurfactant and bioemulsifier, respectively. The compounds showed glycolipid nature but the biosurfactant presented cationic charge, while the bioemulsifier, anionic charge. Thus, the results confirmed that M. hiemalis produced two distinct biomolecules under different parameters and in the same culture medium. CONCLUSIONS: It is the first time that biosurfactant and emulsifier production has been described in the same medium and under different physical conditions by Mucor hiemalis. Both biomolecules showed thermal stability, as well as have significant effect on the viscosity of hydrophobic compounds, indicating the excellent potential for environmental safety or industrial applications to improve the efficiency of sustainable and economic technologies.

Development, characterization and stability of microemulsionated formulations of bacaba, Oenocarpus bacaba oil

Advances in nanotechnology, combined with the use of natural products, represent a promissing research field. Brazil is a country of a rich biodiversity, especially in the Amazon forest. Fruits commonly used by local communities, such as bacaba (Oenocarpus bacaba), are potentially important for prospection of industrial applications of natural products. In nanotechnology, microemulsions stand out for providing a modified release to conveyed substances. This work aimed to develop microemulsionated formulations of bacaba oil, characterize them and evaluate their stability. We determined the HLB (hydrophile-lipophilic balance) of bacaba oil for formulation development. Six formulations were selected from pseudoternary diagrams, which indicated the proportions of surfactants, aqueous phase and bacaba oil. The viability of these formulations was evaluated through stability tests. We provided the rheological characterization of the formulations, evaluated their potential antioxidant activity through the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging method, and determined the hydrodynamic diameter of the droplets. The microemulsions were stable throughout the test period. Droplet diameter was below 200 nm, and the microemulsions were characterized as newtonian fluids, presenting an increase in antioxidant activity when compared with the diluted oil. Our results confirm the potential of bacaba oil in microemulsionated formulation as a suitable carrier for active compounds. (AU)

Effect of branched and straight chained alcohols on performance of crude oil demulsifiers

ABSTRACT: Unwanted crude oil emulsions occur in many stages of oil production, transportation, and processing. The huge cost resulting from corrosion of transport system and production facilities, because of the presence of water is a major challenge to the oil industry and the global economy. However, the addition of alcohols to demulsifiers has been reported to enhance their efficiency in removing water from emulsions. There is therefore the need to identify the best type of alcohols and optimize this process of addition. Consequently in this work, the effect of different straight and branched chain alcohols on the performance enhancement of demulsifiers was investigated using four different crude oil emulsion samples. The results showed that straight alcohols performed better when compared to branched chain alcohols under all conditions of temperature. This may be due to their slow mobility particularly in stable emulsions

Biosurfactant Production by Bacillus strains isolated from sugar cane mill wastewaters

Abstract Biosurfactants possess diverse chemical properties and provide important characteristics to the producing microorganisms, which can act as surface-actives and emulsifiers of hydrocarbon and others water insoluble substances. Most of them are lipopeptides synthetized by Bacillus. This study evaluated the biosurfactant production by strains of Bacillus previously obtained from liquid residues of sugar-alcohol industry. The bacterial isolates LBPMA: BSC, BSD, J1, J2 and L1 were cultivated in medium that induces production of biosurfactants (Landy medium). During 48 h of incubation, at intervals of 12 h, the total contents of proteins, reducing carbohydrates and surfactant activity of the filtrated growth media free of cells were evaluated. The results showed that these strains use glucose as a source of carbon, energy and for synthesis of surfactant. In this medium (24 h), the best producer of biosurfactant was the strain LBPMA-J2, molecularly identified as Bacillus thuringiensis. Once the supernatant free of cells of this microorganism disperses the oil phase in the water, this strain has potential for being utilized on bioremediation processes.

Cloning and heterologous expression of a hydrophobin gene Ltr. hyd from the tiger milk mushroom Lentinus tuber-regium in yeast-like cells of Tremella fuciformis

Background: Hydrophobins are small proteins secreted by filamentous fungi, which show a highly surface activity. Because of the signally self-assembling abilities and surface activities, hydrophobins were considered as candidates in many aspects, for example, stabilizing foams and emulsions in food products. Lentinus tuber-regium, known as tiger milk mushroom, is both an edible and medicinal sclerotium-producing mushroom. Up to now, the hydrophobins of L. tuber-regium have not been identified. Results: In this paper, a Class I hydrophobin gene, Ltr.hyd, was cloned from L. tuber-regium and expressed in the yeast-like cells of Tremella fuciformis mediated by Agrobacterium tumefaciens. The expression vector pGEH-GH was under the control of T. fuciformis glyceraldehyde-3-phosphate dehydrogenase gene (gpd) promoter. The integration of Ltr.hyd into the genome of T. fuciformis was confirmed by PCR, Southern blot, fluorescence observation and quantitative real-time PCR (qRT-PCR). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that recombinant hydrophobin rLtr.HYD with an expected molecular mass of 13 kDa was extracted. The yield of rLtr.HYD was 0.66 mg/g dry weight. The emulsifying activity of rLtr.HYD was better than the typical food emulsifiers sodium caseinate and Tween 20. Conclusions: We evaluated the emulsifying property of hydrophobin Ltr.HYD, which can be potentially used as a food emulsifier.

Potencialidades da succinil quitosana como emulsificante e substituto de fração lipídica em massa de bolo / Potentialities of succinyl chitosan as emulsifier and lipid fraction substitute on cake batter

A necessidade da criação de produtos inovadores com características funcionais está relacionada com a demanda de consumidores que priorizam o bem-estar vinculado a uma alimentação saudável e equilibrado. Nesse sentido, o objetivo deste estudo foi avaliar os efeitos da adição de succinil quitosana (SQ) como um substituto da fração lipídica e agente emulsificante sobre a qualidade de bolos. Para tanto, no capítulo 1 foi realizado um levantamento conciso da literatura para a compreensão dos temas abordados. No capítulo 2, o estudo da SQ se baseou na sua obtenção e caracterização para aplicaçãoem bolos. A análise de infravermelho e difração de raio X validaram as reações de desacetilação e succinilação, sendo que os estudos térmicos demonstraram estabilidade térmica (acima de 300 °C) viabilizando a utilização da SQ em produtos de panificação. A aplicação da suspensão de SQ (2,0 g/100 g) em massas de bolos com níveis reduzidos de gordura (0 % (controle), 25 %, 50 %, 75 % e 100 % (ausência total de gordura)) com ajustes na quantidade de água, para adaptação das consistências das massas, resultou em massas de bolos com parâmetros de viscosidade semelhantes. A redução de gordura até um nível de 50 % e presença de SQ contribuiu para o aumento da área 2D (de 13, 83 para 19,05 mm2) e razão largura/altura, além da umidade e atividade de água. A SQ influenciou significativamente (p < 0,05) na vida de prateleira, visto que a taxa de endurecimento foi de 27,8 (N/dia) para os bolos controle, e em bolos com nível de 25 % apresentou o valor de 26,1 (N/dia) e 49,2 (N/dia) para àqueles com presença total de SQ. Os teores de lipídeos diminuíram significativamente (p < 0,05), embora o conteúdo total de minerais e proteínas tenham apresentado ligeiras variações. Em relação à análise sensorial, foram atribuídas aos bolos com redução de até 50 % de gordura notas entre 6 e 7, e àqueles com 75 % de redução, nota inferior para os atributos de textura, sabor e aspecto geral. Dos provadores, 35 % "provavelmente comprariam" os bolos com 50 % de gordura. Nesse sentido, a SQ pode ser considerada um potencial substituto de gordura em bolos, podendo-se reduzir à metade a quantidade deste ingrediente em sua formulação original, agregando qualidades tecnológicas, sensoriais e nutricionais a esses produtos

The need to create innovative products with functional characteristics is related to the demand of consumers which prioritize the well-being combined to a healthy and balanced diet. In this sense, the objective of this study was to evaluate the effects of the addition of succinyl chitosan (SQ) as an emulsifying agent and lipid fraction substitute on the qualities of cakes. Therefore, in chapter 1 a concise survey of the literature was carried out to understand the themes covered. In chapter 2, the SQ study was based on its obtaining and characterization for application in cakes. Infrared analysis and X-ray diffraction validated the deacetylation and succinylation reactions, and the thermal studies demonstrated thermal stability (above 300 °C), allowing the use of SQ in bakery products. The application of SQ suspension (2.0 g / 100 g) with reduced levels of fat (0 % (control), 25 %, 50 %, 75 % and 100 %) adjusting the amount of water, to adapt the batter's consistencies, resulted in cakes with similar viscosity parameters. The reduction of fat up to 50 % and presence of SQ contributed to the increase of the 2D area (from 13,83 to 19,05 mm2) and width / height ratio, as well as moisture and water activity. SQ significantly influenced (p <0.05) shelf life, since the hardening rate was 27,8 (N / day) for control cakes, and in cakes with a 25% level the value was 26,1 (N / day) and 49.2 (N / day) for those with total presence of SQ. The lipid contents decreased significantly (p <0.05), although the total content of minerals and proteins showed slight variations. Regarding sensory analysis, scores between 6 and 7 were attributed to cakes with a fat reduction of up to 50%, and those with a 75% reduction were attributed a lower score, according to the attributes of texture, taste and overall appearance. From consumers, 35% "I would probably purchase" the cakes with 50% fat. In this sense, SQ may be considered a potential substitute for fat in cakes, and it can reduce the amount of this ingredient by half in its original formulation, adding technological, sensorial and nutritional qualities to these products

Development of self-nanoemulsifying tablet (SNET) for bioavailability enhancement of sertraline

The purpose of the study was to combine the advantages of self-nanoemulsifying drug delivery systems and tablets as a conventional dosage form. Self-nanoemulsifying drug delivery system (SNEDDS) was prepared to enhance the solubility and thus oral bioavailability of sertraline. Aqueous titration method was used to prepare the liquid SNEDDS; ternary phase diagrams were constructed and based on smaller droplet size (24.8 nm), minimum viscosity (153.63 cP) and polydispersity index (0.182), higher percentage transmittance (95%) and in vitro drug release (97%), an optimum system was designated. Liquid SNEDDS was transformed into free-flowing powder by solid adsorption technique followed by compression into tablets. In vitro release of sertraline from liquid and solid SNEDDS was found to be highly significant compared to plain sertraline (p<0.01). Pharmacokinetic studies after oral administration of liquid and solid SNEDDS in rats showed about 6-and 5-fold increased absorption of sertraline compared to the aqueous suspension of sertraline. These studies demonstrate that the solid SNEDDS are promising strategies for successful delivery of poorly water-soluble drug like sertraline

Beef tallow and emulsifier in growing-finishing pig diets

ABSTRACT Two trials were aimed to evaluate beef tallow in diets with and without emulsifier on performance of pigs at growing-finishing phases. In the first trial, 15 barrows (22.03±0.62 kg) were distributed among three treatments: reference diet; test diet 1 (5% beef tallow) and test diet 2 (10% beef tallow). Beef tallow presented average value of 7130.97 kcal ME/kg. For the performance trail, 30 barrows (24.85±1.18 kg) were distributed among five treatments: T1 - diet with soybean oil and 3230 kcal ME /kg; T2 - diet with beef tallow and 3230 kcal ME/kg; T3 - diet with beef tallow and 3080 kcal ME/kg; T4 - diet with beef tallow, 3080 kcal/kg and 0.1% emulsifier; T5 - diet with beef tallow, 2930 kcal ME/kg and 0.1% emulsifier. Feed conversion was worse in animals fed diet with 3080 kcal ME/kg containing beef tallow and with 2930 kcal ME/kg with beef tallow and emulsifier. For economic availability, animals fed diet with beef tallow and 3230 kcal ME/kg and those fed diet with 3080 kcal ME/kg containing beef tallow and emulsifier, did not differ from animals fed diet with soybean oil, which enables the reduction up to 150 kcal ME/kg be compensated by emulsifier addition.

Solid lipid nanoparticles of irbesartan: preparation, characterization, optimization and pharmacokinetic studies

ABSTRACT Irbesartan is an antihypertensive with limited bioavailability and solid lipid nanoparticles (SLN) is one of the approaches to improve bioavailability. Solid lipid nanoparticles were prepared using glyceryl monostearate by solvent emulsification method followed by probe sonication. Irbesartan loaded SLNs were characterized and optimized by parameters like particle size, zeta potential, surface morphology entrapment efficiency and in vitro release. The optimized formulation was then further evaluated for the pharmacokinetic studies in Wistar rats. Irbesartan-loaded SLN of particle size 523.7 nm and 73.8% entrapment efficiency showed good bioavailability in Wistar rats and also showed optimum stability in the studies. The SLN prepared using glyceryl monostearate by solvent emulsification method leads to improve bioavailability of the drug.

Lipofilización del almidón de Dioscorea rotundata P. y su posible uso como agente emulsificante / Lipophilitation of dioscorea rotundata P. starch and its possible use as an emulsifying agent

Objetivo: evaluar la capacidad emulsificante de almidón nativo, hidrolizados e hidrolizados˗lipofilizados a partir del tubérculo de ñame (Dioscorea rotundata). Método: el almidón se obtuvo por el método de rayado y decantación convencionales. Se evaluó el almidón de ñame nativo, que se hidrolizó en medio ácido (40 g almidón+100 mL Agua+3.4 g HCl por 6 horas a 50 °C). Parte del almidón hidrolizado se lipofilizó a dos niveles (10 y 15 mL) mediante reacción con anhídrido dodecenil succínico (DDSA). La capacidad emulsificante se calculó mezclando 25 mL de aceite de maíz, 25 mL de agua y 1 g de almidón por triplicado con fuerte homogenización ( Ultra Turrax®), midiéndose la cantidad de material aún emulsificado luego de 24 horas. Resultados: se apreciaron variaciones de las propiedades en la comparación del almidón nativo. Los porcentajes de sustitución de los almidones, se observa fácilmente la tendencia esperada, es decir, en tanto mayor cantidad de reactivo, mayor sustitución. Se demuestra que la lipofilización del almidón incrementa su capacidad emulsificante. Conclusiones: los almidones lipofilizados con anhidro dodecenil succínico (DDSA) pueden considerarse una nueva alternativa de materia prima en la industria cosmética(AU)

Objectives: to assess the emulsifying capacity of the native starch, the hydrolyzed and hydrolyzed-lipophilyzed products from the tuber Yam (Dioscorea rotundata), Methods: the starch was obtained by the conventional method of grating and decant. Native yam starch was evaluated. It was hydrolyzed in an acid medium (40 g starch+100 mL water+3,4 g HCl for 6 hours at 50 °C). Part of the hydrolyzed starch was lipophilyzed at two levels (10 and 15 mL) through reaction with dodecenyl succinic anhydride (DDSA). The emulsifying capacity was calculated by mixing 25 mL of corn oil, 25 mL of water and 1 g of starch in triplicate with strong homogenization (Ultra Turrax®), and the amount of material still emulsified after 24 hours was then measured. Results: there were observed variations in the native starch properties. It was easy to observe the expected tendency in the substitution percentages of starches, that is, the more reagent, the more substitution. The results showed that the lipophilitation of starch increases the emulsifying capacity. Conclusions: the starches lipophilyzed with dodecenyl succinic anhydride (DDSA) are raw materials that can be considered as a new alternative in the cosmetics industry(AU)

Formulation and characterization of self emulsifing pellets of carvedilol

The purpose of present study was aimed at developing self emulsifying drug delivery system in liquid and then in pellet form that would result in improved solubility, dissolution and permeability of the poorly water soluble drug carvedilol. Pellets were prepared using extrusion-spheronization technique incorporating liquid SEDDS (carvedilol, capmul MCM EP, cremophore EL, tween 20, propylene glycol), adsorbents ( and crospovidone), microcrystalline cellulose and binder (povidone K-30). Ternary phase diagram was constructed to identify different oil-surfactant-cosurfactant mixtures according to the proportion of each point in it. The optimal CAR-SEDDS pellets showed a quicker redispersion with a droplet size of the reconstituted microemulsion being 160.47 nm, which was almost unchanged after solidification. SEM analysis confirmed good spherical appearance of solid pellets; DSC and XRD analysis confirmed that there was no crystalline carvedilol in the pellets. Pellets were then capable of transferring lipophilic compounds into the aqueous phase and significantly enhancing its release with respect to pure drug.

O propósito do presente estudo foi desenvolver um sistema líquido de liberação de fármacos auto emulsificante e, então, na forma de pélete, que poderia resultar em aprimoramento da solubilidade, da dissolução e permeabilidade do fármaco carvedilol, pouco solúvel em água. Os péletes foram preparados utilizando-se a técnica de extrusão-esferonização, incorporando líquido SEDDS (carvedilol, capmul MCM EP, Cremofor EL, Tween 20, propileno glicol), adsorventes (e crospovidona), celulose microcristallina e ligante (povidona K-30). O diagrama de fase ternário foi construído para identificar as misturas diferentes de óleo-tensoativo-co-tensoativo, de acordo com a proporção em cada ponto delas. Os péletes CAR-SEDDS mostraram redispersão mais rápida, com tamanho de gota da microemulsão reconstituída de 160,47 nm, que se mostrou quase inalterada após a solidificação. A análise por SEM confirmou a aparência esférica dos péletes sólidos. Análise por DSC e XRD confirmou que não havia carvedilol cristalino nos péletes. Estes foram, então capazes de transferir os compostos lipofílicos para a fase aquosa, aumentando, significativamente, sua liberação em relação ao fármaco puro.

Development and optimization of self microemulsifying drug delivery of domperidone

The present investigation is aimed to develop self-microemulsifying drug delivery system (SMEDDS) to improve the in vitro dissolution of a BCS (Biopharmaceutical Classification System) class II anti emetic agent, domperidone. Solubility study was performed to identify the ingredients showing highest solubility of domperidone. The ternary phase diagrams were plotted for selected components to identify the area of microemulsion existence. D-optimal mixture experimental design was applied to optimize a liquid SMEDDS using formulation variables; the oil phase X1 (Oleic acid), the surfactant X2 (Labrasol) and the co-surfactant X3 (Transcutol HP). The liquid SMEDDS were evaluated for droplet size, emulsification time, % transmittance and drug release. Stability study was performed at 40 °C/75% RH. Liquid formulation was solidified by adsorption on carrier Aerosil 300. Solid SMEDDS was evaluated and compared with liquid SMEDDS and marketed formulation. Oleic acid was selected as oil, Labrasol as surfactant and Transcutol HP as co-surfactant for formulation of SMEDDS. The optimized batch showed best results in terms of smaller droplet size (<170 nm), emulsification time (<40 s) and drug release (>85% in 15 min) and was stable for 3 months. Solid SMEDDS containing Aerosil 300 showed good flow properties and uniform drug content. XRPD study revealed that the crystalline drug was converted to amorphous form in solid SMEDDS. The rate and extent of drug dissolution from solid SMEDDS was significantly higher than pure drug and commercial tablet formulation. The results demonstrate the potential of SMEDDS as a means of improving solubility, dissolution and hence the bioavailability.

O presente estudo teve como objetivo desenvolver sistemas de liberação auto-microemulsificantes (Self-Microemulsifying Drug Delivery System - SMEDDS) de domperidona, agente antiemético, classe II, segundo o sistema de classificação Biofarmacêutica, para melhorar sua dissolução in vitro. Estudo foi realizado para identificar os componentes que revelaram maior solubilidade da domperidona. Determinaram-se os diagramas de fase ternários para esses componentes selecionados tendo em vista a identificação da região de formação da microemulsão. O planejamento experimental foi empregado para otimizar os SMEDDS líquidos, utilizando as seguintes variáveis de formulação: a fase oleosa X1 (ácido oleico), o agente tensoativo X2 (Labrasol) e co-tensoativo X3 (Transcutol HP). Os SMEDDS líquidos foram avaliados quanto às seguintes características: tamanho da gota, tempo de emulsificação,% de transmitância e liberação do fármaco. O estudo de estabilidade foi realizado a 40 °C/75% de umidade relativa. A formulação foi convertida em forma sólida por sua adsorção em Aerosil 300. Os SMEDDS sólidos foram avaliados e comparados com SMEDDS líquidos e a formulação comercializada. O ácido oléico foi selecionado para a fase oleosa, Labrasol como agente tensoativo e Transcutol como co-tensoativo para a formulação de SMEDDS. O lote otimizado mostrou os melhores resultados: menor tamanho de gota (<170 nm), menor tempo de emulsificação (<40 segundos), e de liberação do fármaco (> 85% em 15 min). Além disso, a formulação otimizada manteve-se estável no período de 3 meses. Os SMEDDS sólidos contendo Aerosil 300 apresentaram boas propriedades de fluxo e uniformidade de conteúdo do fármaco. O estudo de difração de raios-X revelou que o fármaco cristalino foi convertido para a forma amorfa, nos SMEDDS sólidos. A velocidade de dissolução do fármaco a partir dos SMEDDS sólidos foi significativamente maior, quando comparado ao fármaco livre e à formulação de comprimidos comercial. Os resultados demonstram o potencial dos SMEDDS como meio para melhorar a solubilidade, a dissolução e, consequentemente, a biodisponibilidade da domperidona.

Design and optimization of self-microemulsifying drug delivery system (SMEDDS) of felodipine for chronotherapeutic application

The objective of this research work was to design, develop and optimize the self micro-emulsifying drug delivery system (SMEDDS) of Felodipine (FL) filled in hard gelatine capsule coated with polymer in order to achieve rapid drug release after a desired time lag in the management of hypertension. Microemulsion is composed of a FL, Lauroglycol FCC, Transcutol P and Cremophor EL. The optimum surfactant to co-surfactant ratio was found to be 2:1. The resultant microemulsions have a particle size in the range of 65-85 nm and zeta potential value of -13.71 mV. FL release was adequately adjusted by using pH independent polymer i.e. ethyl cellulose along with dibutyl phthalate as plasticizer. Influence of formulation variables like viscosity of polymer, type of plasticizer and percent coating weight gain was investigated to characterize the time lag. The developed formulation of FL SMEDDS capsules coated with ethyl cellulose showed time lag of 5-7 h which is desirable for chronotherapeutic application.

O objetivo desse trabalho de pesquisa foi planejar, desenvolver e otimizar sistema de liberação de fármaco auto-microemulsificante(SMEDDS) de felodipino (FL) em cápsulas de gelatina dura revestidas com polímero, a fim de obter liberação rápida após tempo desejado no manejo da hipertensão. A microemulsão é composta de FL, lauroglilcol FCC, Transcutol P e Cremophor EL. A proporção ótima de tensoativo e de co-tensoativo foi de 2:1. As microemulsões resultantes têm tamanho de partícula na faixa de 65-85 nm com potencial zeta de -13,71 mV. A liberação de FL foi ajustada adequadamente, utilizando-se polímero independente de pH, como etilcelulose com ftalato de dibutila como plastificante. A influência das variáveis da formulação, como viscosidade do polímero, tipo de plastificante e ganho percentual de peso do revestimento foi investigada para caracterizar o intervalo de tempo de liberação. A formulação de cápsulas de FL SMEDDS revestidas com etilcelulose mostrou intervalo de tempo de liberação de 5 a 7 horas, o que é desejável para uma aplicação cronoterapêutica.

Characterization and stability studies of emulsion systems containing pumice

Emulsions are the most common form of skin care products. However, these systems may exhibit some instability. Therefore, when developing emulsions for topical application it is interesting to verify whether they have suitable physical and mechanical characteristics and further assess their stability. The aim of this work was to study the stability of emulsion systems, which varied in the proportion of the emulsifying agent cetearyl alcohol (and) sodium lauryl sulfate (and) sodium cetearyl sulfate (LSX), the nature of the oily phase (decyl oleate, cyclomethicone or dimethicone) and the presence or absence of pumice (5% w/w). While maintaining the samples at room temperature, rheology studies, texture analysis and microscopic observation of formulations with and without pumice were performed. Samples were also submitted to an accelerated stability study by centrifugation and to a thermal stress test. Through the testing, it was found that the amount of emulsifying agent affects the consistency and textural properties such as firmness and adhesiveness. So, formulations containing LSX (5% w/w) and decyl oleate or dimethicone as oily phase had a better consistency and remained stable with time, so exhibited the best features to be used for skin care products.

Emulsões são a forma de apresentação mais comum dos produtos para aplicação na pele. No entanto estes sistemas podem exibir alguma instabilidade. Por esta razão, quando do desenvolvimento de emulsões para aplicação tópica é importante verificar se estas apresentam propriedades físicas ou mecânicas adequadas e avaliar a sua estabilidade. O objetivo deste trabalho consistiu no estudo da estabilidade de emulsões, cujas variações entre elas foi a proporção de agente emulsificante álcool estearílico (mais) laurilsulfato de sódio (mais) estearilsulfato de sódio (LSX), a natureza da fase oleosa (decil oleato, ciclometicona ou dimeticona) e a presença ou ausência de pedra-pomes (5% m/m). Mantendo as amostras à mesma temperatura, realizaram-se o estudo da reologia, a análise de textura e observação microscópica das formulações com e sem pedra-pomes. Amostras foram, também, submetidas a estudo de estabilidade acelerada por centrifugação e a ensaio de estresse térmico. Através dos testes realizados, constatou-se que a quantidade de agente emulsificante influencia a consistência e as propriedades de textura, como a firmeza e a adesividade. As formulações contendo LSX (5% m/m) e decil oleato ou dimeticona como fase oleosa exibiram melhores caraterísticas como produtos para aplicação na pele, uma vez que estas formulações apresentaram menor firmeza e consistência e permaneceram estáveis com o tempo.

Mechanisms of hydroxypropyl methylcellulose for the precipitation inhibitor of supersaturatable self-emulsifying drug delivery systems / 药学学报

Hydroxypropyl methylcellulose (HPMC) propels self-emulsifying drug delivery systems (SEDDS) to achieve the supersaturated state in gastrointestinal tract, which possesses important significance to enhance oral absorption for poorly water-soluble drugs. This study investigated capacities and mechanisms of HPMC with different viscosities (K4M, K15M and K100M) to inhibit drug precipitation of SEDDS in the simulated gastrointestinal tract environment in vitro. The results showed that HPMC inhibited drug precipitation during the dispersion of SEDDS under gastric conditions by inhibiting the formation of crystal nucleus and the growth of crystals. HPMC had evident effects on the rate of SEDDS lipolysis and benefited the distribution of drug molecules across into the aqueous phase and the decrease of drug sediment. The mechanisms were related to the formed network of HPMC and its viscosities and molecular weight. These results offered a reference for selecting appropriate type of HPMC as the precipitation inhibitor of supersaturatable SEDDS.

Statistical optimization of dithranol-loaded solid lipid nanoparticles using factorial design / Otimização estatística de nanopartículas lipídicas sólidas carregadas com ditranol utilizando planejamento fatorial

This study describes a 3² full factorial experimental design to optimize the formulation of dithranol (DTH) loaded solid lipid nanoparticles (SLN) by the pre-emulsion ultrasonication method. The variables drug: lipid ratio and sonication time were studied at three levels and arranged in a 3² factorial design to study the influence on the response variables particle size and percent entrapment efficiency ( percentEE). From the statistical analysis of data polynomial equations were generated. The particle size and percentEE for the 9 batches (R1 to R9) showed a wide variation of 219-348 nm and 51.33- 71.80 percent, respectively. The physical characteristics of DTH-loaded SLN were evaluated using a particle size analyzer, differential scanning calorimetry and X-ray diffraction. The results of the optimized formulation showed an average particle size of 219 nm and entrapment efficiency of 69.88 percent. Ex-vivo drug penetration using rat skin showed about a 2-fold increase in localization of DTH in skin as compared to the marketed preparation of DTH.

Este estudo descreve o planejamento factorial 3² para otimizar a formulação de nanopartículas lipídicas sólidas (SLN) carregadas com ditranol (DTH) pelo método da ultrassonificação pré-emulsão. As variáveis como proporção de fármaco:lipídio e o tempo de sonicação foram estudados em três níveis e arranjados em planejamento fatorial 3² para estudar a influência nas variáveis de resposta tamanho de partícula e eficiência percentual de retenção do fármaco ( por centoEE). Pela análise estatística, geraram-se equações polinomiais. O tamanho da partícula e a por centoEE para os 9 lotes (R1 a R9) mostraram ampla variação, respectivamente, 219-348 nm e 51,33-71,80 por cento. As características físicas das SLN carregadas com DTN foram avaliadas utilizando-se analisador de tamanho de partícula, calorimetria de varredura diferencial e difração de raios X. Os resultados da formulação otimizada mostraram tamanho médio de partícula de 219 nm e eficiência de retenção do fármaco de 69,88 por cento. A penetração ex vivo do fármaco utilizando pele de rato mostrou aumento de, aproximadamente, duas vezes na localização de DTH na pele, comparativamente à preparação de DTH comercializada.

Optimization of novel self-microemulsifying mouth dissolving films by response surface methodology / 药学学报

This paper report the development of a new dosage form - self-microemulsifying mouth dissolving films, which can improve the oral bioavailability of water insoluble drugs and have good compliance. A three factor, three-level Box-Behnken design was used for optimizing formulation, investigated the effect of amounts of microcrystalline cellulose, low-substituted hydroxypropyl cellulose and hypromellose on the weight, disintegration time, cumulative release of indomethacin after 2 min, microemulsified particle size and stretchability. Optimized self-microemulsifying mouth dissolving films could fast disintegrate in (17.09 +/- 0.72) s; obtain microemulsified particle size at (28.81 +/- 3.26) nm; and release in vitro at 2 min to (66.18 +/- 1.94)%. Self-microemulsifying mouth dissolving films with broad application prospects have good compliance, strong tensile and can be released rapidly in the mouth through fast self-microemulsifying.

Influência da adição de lecitina de soja e do poliglicerol poliricinolato nas propriedades reológicas do chocolate / Influence of addition of soy lecithin and polyglycerol poliricinolato the rheological properties chocolate

O objetivo deste trabalho foi avaliar o comportamento reológico de chocolate do tipo meio-amargo, variando-se os teores de lecitina e poliglicerol poliricinolato (PGPR). As amostras de chocolate foram preparadas adicionando-se de 0,3 a 1,4% (m/m) de lecitina e a combinação de lecitina/PGPR com PGPR constante de 0,2% e variando-se o teor de lecitina em 0,3, 0,5 e 0,8%. As análises reológicas foram realizadas nas temperaturas de 40ºC (início da temperagem) e de 31ºC (final da temperagem). No início da temperagem, até o percentual de 0,5% de lecitina houve redução na viscosidade plástica e aparente. O limite de escoamento apresentou aumento após a adição de 0,5% de lecitina. Para as amostras contendo lecitina e PGPR, o comportamento das curvas de viscosidade e o limite de escoamento foi semelhante ao das amostras contendo apenas a lecitina. A adição de diferentes teores de emulsificantes não interferiu nos parâmetros da temperagem.

Selection of biosurfactan/bioemulsifier-producing bacteria from hydrocarbon-contaminated soil

Petroleum-derived hydrocarbons are among the most persistent soil contaminants, and some hydrocarbon-degrading microorganisms can produce biosurfactants to increase bioavailability and degradation. The aim of this work was to identify biosurfactant-producing bacterial strains isolated from hydrocarbon-contaminated sites, and to evaluate their biosurfactant properties. The drop-collapse method and minimal agar added with a layer of combustoleo were used for screening, and positive strains were grown in liquid medium, and surface tension and emulsification index were determined in cell-free supernantant and cell suspension. A total of 324 bacterial strains were tested, and 17 were positive for the drop-collapse and hydrocarbon-layer agar methods. Most of the strains were Pseudomonas, except for three strains (Acinetobacter, Bacillus, Rhodococcus). Surface tension was similar in cell-free and cell suspension measurements, with values in the range of 58 to 26 (mN/m), and all formed stable emulsions with motor oil (76-93 percent E24). Considering the variety of molecular structures among microbial biosurfactants, they have different chemical properties that can be exploited commercially, for applications as diverse as bioremediation or degradable detergents.