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Aerosolized Surfactants: Formulation Development and Evaluation of Aerosol Drug Delivery to the Lungs of InfantsBoc, Susan 01 January 2018 (has links)
The overall aim of this research project was to develop surfactant dry powder formulations and devices for efficient delivery of aerosol formulations to infants using the excipient enhanced growth (EEG) approach. Use of novel formulations and inline delivery devices would allow for more efficient treatment of infants suffering from neonatal respiratory distress syndrome and bronchiolitis.
A dry powder aerosol formulation has been developed using the commercial product, Survanta ® (beractant) and EEG technology to produce micrometer-sized hygroscopic particles. Spray drying and formulation parameters were initially determined with dipalmitoylphosphatidylcholine (DPPC, the dominant phospholipid in pulmonary surfactant), which produced primary particles 1 um in size with a mass median aerodynamic diameter of 1-2 um.
Investigation of dry powder dispersion enhancers and alcohol concentration on the effect of powder aerosol characteristics were performed with the Survanta-EEG formulation. The optimal formulation consisted of Survanta ® , mannitol and sodium chloride as hygroscopic excipients, and leucine as the dry powder dispersion enhancer, prepared in 20% v/v ethanol/water. The powders produced primary particles of 1 um with >50% of the particles less than 1 um. The presence of surfactant proteins and surface activity were demonstrated with the Survanta-EEG formulation following processing.
A novel containment unit dry powder inhaler (DPI) was designed for delivery of the surfactant-EEG formulation using a low volume of dispersion air. Studies explored optimization of air entrainment pathway, inlet hole pattern, delivery tube internal diameter and length. With 3- 10 mg fill masses of spray dried surfactant powder, the DPI enabled delivery of >2 mg using one 3-mL actuation of dispersion air. Overall, it was possible to deliver >85% of the loaded fill mass using three actuations.
Nebulized aerosol formulations are characterized with low delivered doses. Using a novel mixer-heater delivery system, the highest estimated percent lung dose achieved during realistic in vitro testing of a Survanta-EEG formulation aerosolized with a commercial mesh nebulizer was when nebulization was synchronized with inhalation of the breathing profile. Design changes to the mixer-heater system eliminated the need for synchronization, achieving an estimated percent lung dose of 31% of the nominal, an improvement compared with existing systems that achieve approximately <2% lung dose.
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Nano-dispersing Lipophilic Antimicrobials for Improved Food SafetyShah, Bhavini Dipak 01 December 2011 (has links)
Naturally occurring food antimicrobials such as plant essential oils are receiving tremendous interest as intervention systems to enhance microbiological safety and quality. Poor water solubility of essential oils makes it difficult to incorporate them in foods, impacting visual appearance, antimicrobial effectiveness, and possibly organoleptic properties. Engineered nanoscale delivery systems can principally solve these challenges, but those based on low-cost food ingredients and inexpensive and scalable processes are currently scarce. This dissertation presents a simple and scalable two-step technology to prepare nano-delivery systems. The first encapsulation step, based on emulsion-evaporation, involves preparing emulsions composed of an oil phase with thymol or eugenol, major compounds in extracts from thyme and clove respectively, in hexane and an aqueous phase with conjugates of whey protein isolate and maltodextrin, followed by evaporation of hexane by spray drying. The second step is to hydrate spray dried capsules to enable the formation of nanoscale particles. The encapsulation performance and dispersion characteristics were affected by amounts and types of conjugates (ratio of protein: maltodextrin and maltodextrin chain length), volume fraction and composition of the oil phase. The optimal conditions corresponded to 55.8 % encapsulation efficiency and 12.6 % loading for thymol and 47.9 % encapsulation efficiency and 7.9 % loading for eugenol. Dispersions prepared from the identified capsules contained particles smaller than 100 nm and were transparent at pH 3.0-7.0 and 0-50 mM before and after heating at 80°C for 15 min. Nano-dispersions and free oil were tested for antimicrobial activity against Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Salmonella typhimurium. Nano-dispersed and free antimicrobials had similar effectiveness at various pH and temperatures in tryptic soy broth and apple cider, while in 2 % reduced fat milk, nano-dispersed antimicrobials were consistently more effective than unencapsulated ones. Therefore, the commercially viable nanoscale technology presented in this study enables the delivery of lipophilic antimicrobials for enhanced microbial safety and quality, without compromising visual appearance of foods, especially clear beverages.
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Air-suspension coating of dairy powders : a micro-level process approach : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Technology at Massey University, Palmerston North, New ZealandWerner, Stephen R. L. January 2005 (has links)
Air-suspension particle coating is a process by which thin coatings are applied to powder particles. The coatings can be formulated to act as permeable barriers to increase powder shelf-life or to impart controlled release character. The ultimate objective of a coating operation is to produce individual particles, each with a well-controlled, even coating. This project was focused on the air-suspension coating of fine powders of ~100 µm in diameter for the dairy industry. Despite the widespread use of the technology in the pharmaceutical industry, its use in the food industry has been limited. Little is known about the fundamental mechanisms, and so published work to date is product and equipment specific and is statistical in the way the experimental design and analysis has been approached. This 'black box' approach is time consuming and costly. Better methods based on an understanding of the physical and chemical mechanisms are needed to deal with the numerous products and constantly changing formulations typical of the dairy industry. This thesis proposes a new approach to air-suspension particle coating research. The basis of this 'micro-level process approach', is to deconvolute the complex coating process into smaller manageable parts based on classical physical phenomena for which descriptions already exist. The thesis identifies and develops an understanding of the key micro-level processes controlling coated product quality and process performance. Four were selected for further study: drying, droplet impact and spreading, and stickiness which encompasses the two key micro-level processes of droplet impact and adherence and inter-particle agglomeration. They were studied separately to deconvolute the variable effects and interactions. Kinetic data were collected for the drying droplets containing maltodextrins, whey protein isolate and gum arabic. A mathematical model, based on 'ideal shrinkage' was developed to predict the drying kinetics of single droplets with particular interest in the development of the surface glass transition temperature. The model accurately predicted the kinetics until significant morphological changes occurred in the droplet. To better predict the kinetics late in the drying process, the droplet radius was set to be constant at a time based on the surface proximity to the surface glass transition temperature (critical X concept). This was done to arrest droplet shrinkage in line with experimental observations and to more accurately depict the drying of high molecular weight, amorphous glass forming polymers. After this point, a new flexible calculation scheme was used to better predict the variation in internal droplet structure as either a dense, 'collapsed shell' structure or a 'dense skin-porous crumb' structure. Further study should focus on the surface and internal droplet structure (porosity and mechanical integrity) development during drying, particularly the conditions leading to the arresting of the droplet radius and the subsequent rate of skin thickness progression. The critical X concept was used to make industrial-scale predictions of the optimum drying conditions that ensure maximum droplet impact and adherence efficiency and minimum inter-particle agglomeration in a Würster-style coating operation. This enabled the prediction of two key design parameters, the nozzle distance from the powder impact point and the Würster insert height. The span in design parameters showed that there is significant opportunity for design optimisation based on the critical X concept. A probe tack test was used to map the level of stickiness of droplets of different coating materials as they dried. As skin formation progressed, the stickiness passed through a maximum, in most cases to arrive at a point at which the droplet was no longer sticky at all (non-adhesive state). The maximum point of stickiness represents the ideal state to ensure successful droplet-substrate impact and adherence. The minimum point of stickiness represents the ideal state to prevent unwanted inter-particle agglomeration. The time interval between the onset of stickiness and the non-adhesive state was particularly dependent on the addition of plasticisers, but also on the formulation and the drying air conditions. Future work should look to establish a possible relationship between the surface glass transition temperature and the probe tack test stickiness measurements. The impact and spreading of droplets containing maltodextrin DE5 on to solid anhydrous milkfat was studied using a high speed video camera. It was found that the final spread diameter was able to be fixed close to the maximum spread diameter by using surfactants, thus avoiding significant recoil. Because existing literature focuses on predicting the maximum spread diameter, this work defines a need for adequate prediction methods for the final spread diameter, as this is the significant parameter in coating applications. Formulation and operating guidelines were established to independently optimise each micro-level process. These were used in a series of population based coating experiments in a pilot-scale Würster coater. This study highlighted the limited flexibility of the standard 'off-the-shelf' Würster coating apparatus for the coating of fine sized dairy powders. Because of this, the validation of the guidelines were inconclusive and optimisation could not be carried out. Further validation work is required on a custom-built apparatus for dairy powders. This work has advanced the fundamental knowledge of the coating process and is independent of material, equipment and scale. This knowledge, based on physical and chemical mechanisms, can be used to develop coating formulations and identify optimum process conditions for successful coating in less time and at less expense than is current practice. The next step is to put the guidelines into practice and craft the engineering of a continuous coating apparatus for dairy powder applications.
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Micropartículas contendo pantoprazol sódico: desenvolvimento tecnológico, produção em escala piloto e avaliação biológica / Micropartcles contaning sodium pantoprazole : technological development, scale up and biological activityRaffin, Renata Platcheck January 2007 (has links)
Micropartículas contendo pantoprazol foram preparadas e caracterizadas a fim de se obter sistemas multiparticulados gastro-resistentes. O trabalho foi delineado buscando-se a melhor técnica de preparação das micropartículas, assim como o estudo do processo, aumento de escala e avaliação biológica. A metodologia analítica para quantificação do pantoprazol nas micropartículas foi desenvolvida e validada. O método mostrou-se seletivo, linear, preciso e exato. A estabilidade do pantoprazol em tampão fosfato pH 7,4 foi avaliada para verificar a viabilidade da utilização deste tampão como meio de dissolução. O pantoprazol apresentou-se estável durante 6 h e considerado adequado para estudos de dissolução. A primeira técnica utilizada na preparação de micropartículas foi a evaporação de solvente, utilizando uma emulsão O/O. O polímero utilizado foi Eudragit® S100. As micropartículas apresentaram diâmetro de 56 μm e, segundo análises de DSC e IV, o fármaco apresentou-se molecularmente disperso no polímero. As micropartículas apresentaram atividade anti-ulcerogênica em modelo de ulceração gástrica em ratos por etanol, enquanto a solução aquosa de pantoprazol não apresentou atividade. Estas micropartículas foram comprimidas e permaneceram intactas no interior dos comprimidos. Quanto à proteção do pantoprazol em meio ácido, 61 % da quantidade inicial do fármaco permaneceram estáveis após 30 min em meio ácido. Uma segunda formulação utilizando a mesma técnica foi preparada coma a adição de poli(ε-caprolactona) à formulação de Eudragit® S100. O objetivo da inclusão do segundo polímero foi a obtenção de uma blenda capaz de promover liberação controlada do pantoprazol e ao mesmo tempo conferir gastro-resistência. Esta formulação também apresentou atividade anti-ulcerogênica in vivo. Os comprimidos contendo estas micropartículas apresentaram liberação controlada e gastroresistência. A segunda técnica avaliada no desenvolvimento de micropartículas contendo pantoprazol foi a secagem por aspersão. Micropartículas contendo Eudragit® S100 foram produzidas e apresentaram bom rendimento, eficiência de encapsulação e estabilização do pantoprazol em meio ácido. As micropartículas foram avaliadas quanto a permeação intestinal utilizando modelo de intestino invertido. A permeação intestinal foi diretamente proporcional à liberação em tampão fosfato pH 7,4, estabelecendo uma correlação de nível A. Devido a esses fatores, estas micropartículas foram selecionadas para preparação em escala piloto. Diferentes condições operacionais foram testadas e o diâmetro médio das partículas xxiv variou entre 6.7 e 24.5 μm, influenciado pela concentração inicial de sólidos. As condições operacionais que produziram micropartículas com maior gastroresistência foram selecionadas para estudo de estabilidade. As micropartículas apresentaram-se estáveis por 6 meses em condições aceleradas de armazenamento e não adsorveram umidade ao longo do tempo. A avaliação in vivo demonstrou a atividade anti-ulcerogênica desta formulação. No entanto, a formulação apresentou baixa densidade e fluxo pobre, dificultando a granulação e compressão. A forma farmacêutica desenvolvida foram aglomerados ou soft pellets, contendo micropartículas de pantoprazol e um excipiente de manitol e lecitina preparado por spray-drying. Os aglomerados apresentaram adequadas características de fluxo e rápida desintegração não afetando a gastro-resistência das micropartículas. A técnica de spray-drying também foi utilizada com uma blenda de Eudragit® S100 e HPMC, também visando uma liberação controlada do pantoprazol. As micropartículas apresentaram alta eficiência de encapsulação e também reduziram a formação de úlceras gástricas por etanol em ratos. Os comprimidos contendo micropartículas preparadas com a blenda apresentaram mais de 90 % de estabilização em meio ácido. Este processo também foi escalonado e as melhores condições operacionais determinadas. O processo foi reprodutível em relação ao diâmetro, densidade, eficiência de encapsulação e gastro-resistência. Esta formulação foi estável por 6 meses a 40 °C e 75 % de umidade. As quatro formulações descritas neste trabalho foram testadas quanto à estabilização do pantoprazol frente à luz UVC. O pantoprazol demonstrou ser fotoinstável tanto em solução metanólica como sólido e apenas as micropartículas preparadas com Eudragit® S100 aumentaram a fotoestabilidade do pantoprazol. Baseado no conjunto de resultados, os aglomerados contendo micropartículas de Eudragit® S100 foram selecionadas para serem testadas quanto a sua farmacocinética, em comparação com o comprimido comercial de referência. Os aglomerados demonstraram ser mais rapidamente absorvidos, reduzindo o Tmax de 90 para 43 min, mantendo mesma biodisponibilidade oral. Desta forma, podemos concluir que o pantoprazol foi microencapsulado com sucesso e as micropartículas aumentaram a estabilidade do fármaco em meio ácido e frente à luz, além de reduzir o tempo para atingir a concentração máxima do mesmo. / The aim of the thesis is to develop, characterize and evaluate two drug delivery systems containing gastro-resistant pantoprazole microparticles, one for the prompt dissolution and the other one for controlled release of pantoprazole. First, an analytical method was developed and validated for the quantification of sodium pantoprazole by HPLC. The stability of pantoprazole in phosphate buffer at pH 7.4 was also evaluated during 22 days. The results showed that the method was specific, linear, precise and exact. Pantoprazole was stable in phosphate buffer pH 7.4 for 6 h. Then, the solvent evaporation technique was applied in the preparation of gastroresistant pantoprazole-loaded microparticles using an O/O emulsion. Furthermore, tablets containing the microparticles were also investigated. Microparticles presented spherical and smooth morphologies and they remained intact in the inner surface of tablets. DSC and IR analyses showed that pantoprazole was physically and molecularly dispersed in the polymer. In vivo anti-ulcer evaluation showed that the microparticles were able to protect the rat stomachs against ulcer formation by ethanol, while the drug aqueous solution did not present activity. Concerning the acid protection, tablets showed a satisfactory drug protection in acid medium (61 % after 30 min). As a second formulation, microparticles of poly(ε-caprolactone) blended with Eudragit® S100 were prepared in order to provide controlled release and gastroresistance. This formulation showed in vivo protection of stomachs against ulceration caused by ethanol in rats. These microparticles were tableted and the tablets demonstrated slower drug release and higher acid protection than the microparticles before tableting. The spray drying technique was also used to prepare pantoprazoleloaded microparticles. Microparticles containing pantoprazole and Eudragit S100® presented high encapsulation efficiency and good stabilization in acid medium. Microparticles prevented ulceration by ethanol in vivo. These microparticles showed more adequate characteristics for the preparation of a drug delivery system than the one prepared by solvent evaporation. The physical characteristics of pantoprazole microparticles produced in different spray dryers and operational conditions were investigated. In all conditions tested it was possible to obtain powders that presented spherical shape microparticles, with mean sizes from 6.7 to 24.5 μm. The size was xxvi mainly affected by the initial feed concentration (2.2 or 6.6% w/w). All powders presented very poor flow. Under accelerated conditions of storage, the selected microparticles were stable for 6 months. The microparticles couldn’t be tableted and then, the microparticles were agglomerated with mannitol/lecithin powder. The agglomerates presented good technological properties and did not influence the drug release and the gastro-resistance of the pantoprazole microencapsulated. The spray drying technique was also used to prepare microparticles aiming to provide gastroresistance and to control the drug release, using a blend of Eudragit S100® and HPMC. DSC analyses showed that the drug is molecularly dispersed in the microparticles, and in vivo anti-ulcer evaluation demonstrated that microparticles were effective in protecting stomach against ulceration. In vitro gastro-resistance study showed that the microparticles stabilized pantoprazole in 62.0 % and tablets containing the microparticles in 97.5 % and provided a controlled release of the drug. This formulation was also studied in different scales of production and spray-drier designs. The microparticles were produced in different spray-driers and operational conditions at laboratory and pilot scales. The microparticles produced with two fluid nozzle atomizer and 196 kPa were prepared in three consecutive days for the process validation. The powders showed reproducible diameter, low polydispersity, similar bulk densities, encapsulation efficiency and gastro-resistance. These microparticles were evaluated for their accelerate stability. The microparticles presented less than 5 % of degradation after 180 days at 40 °C and 75 % of RH. These same microparticles were agglomerated using mannitol/lechitin spray-dried as excipient. Different amounts of lecithin and mannitol were used, but only one formulation did not alter the pantoprazole release from the microparticles, as well as the gastro-resistance. The four different formulations of microparticles characterized in this study were tested for the stabilization of pantoprazol under UVC light. Only the microparticles prepared with Eudragit® S100 improved the drug photostability. Based on the results, the agglomerates containing microparticles prepared by spray-drying with Eudragit® S100 were selected for the pharmacokinetics study in dogs. The agglomerates presented similar AUC than the reference tablet, but reduced the Tmax. In conclusion, pantopazole-loaded microparticles were successfully prepared and the stability of pantoprazol in acid medium and under light was improved. Furthermore, the time to peak plasma was reduced.
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Avaliação da influência de adjuvantes de secagem sobre as propriedades de suco de caju atomizado / Evaluation of the influence of drying aid on the atomized cashew juice propertiesOliveira, Mirela Araújo de January 2008 (has links)
OLIVEIRA, Mirela Araújo de. Avaliação da influência de adjuvantes de secagem sobre as propriedades de suco de caju atomizado. 2008. 63 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Curso de Pós-Graduação em Tecnologia de Alimentos, Fortaleza-CE, 2008 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-21T15:44:25Z
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Previous issue date: 2008 / The fruit industries have been compelled to adapt to the increasing consumer requeriments related to convenience, food safety and health benefits. An evidence of such changes is the increasing production of fruit juices and related products. Although the ready-to-drink fruit nectars are convenience products, they have high weight and volume, since they have water as their main component. This is an inconvenient aspect, and increases transportation costs. The powder juices have some advantages over whole juices, such as easier and cheaper transportation and higher microbial stability. However, the consumers seem to confuse powder juices with the more commonly found fruit-flavored powder drinks, impairing the consolidation of the former in the market. Cashew (Anacardium occidentale) is a fruit from Brazilian Northeast, having great socio-economic importance for that region. It contains the cashew nut (the real fruit) and the cashew apple (pseudofruit). The low stability of the fresh cashew apple has motivated the development of processes to obtain more shelf-stable products which could be available all year long, and at the same time easy to transport to distant markets. Spray drying is the most used technique to dry liquid foods. However, sugar-rich foods such as fruit juices are difficult to dry, since they produce too hygroscopic powders, which are prone to caking and flowing problems. This can be minimized by addition of drying-aids, such as maltodextrins, which reduce their hygroscopicity. The present study involved an attempt to totally or partially replace maltodextrins (MD) by cashew tree gum (CTG), a polysaccharide similar to gum arabic, very abundant in Brazilian Northeast but under-utilized. The objective of the work was to evaluate the impact of two variables – drying aid/cashew apple solids (DA/CA) ratio (2:1-5:1) and degree of replacement of MD with CTG (0-100%), according to a central composite design – on ascorbic acid retention, physical properties (hygroscopicity and flowability) and solubility of spray dried cashew apple juice. The ascorbic acid retention was favored by higher DA/CA ratios and higher replacements of MD. Cashew tree gum was shown as a promising drying aid material. The most adequate drying conditions were considered as being the following: DA/CA ratio, 5:1, with CTG replacing MD in at least 50%. / As indústrias de frutas têm sofrido pressões para se adaptar aos crescentes requerimentos dos consumidores, relacionados a conveniência, segurança alimentar, e benefícios à saúde. Uma evidência de tais mudanças é o aumento da produção de sucos de frutas e produtos similares. Embora os néctares, prontos para beber, sejam produtos de conveniência, eles têm alto peso e volume, já que têm a água como principal componente. Esse é um aspecto inconveniente, e aumenta os custos de transporte. Os sucos em pó têm algumas vantagens sobre os sucos integrais, como o transporte mais fácil e barato e sua maior estabilidade microbiológica. No entanto, o consumidor parece ainda confundir sucos em pó com refrescos artificiais em pó, mais comumente encontrados, o que prejudica a consolidação dos primeiros no mercado. O caju (Anacardium occidentale) é uma fruta originária do Nordeste brasileiro, para o qual apresenta grande importância socioeconômica. É formado por castanha (verdadeiro fruto) e pedúnculo (pseudofruto). A alta perecibilidade do pedúnculo in natura tem motivado o desenvolvimento de processos que gerem produtos estáveis, disponíveis ao longo do ano, ao mesmo tempo facilitando seu transporte para longe da região produtora. A atomização é a técnica mais utilizada para secagem de alimentos líquidos. Entretanto, produtos ricos em açúcares, como sucos de frutas, são difíceis de atomizar, pois produzem pós muito higroscópicos, suscetíveis a aglomeração. Isso pode ser minimizado pela adição dos chamados adjuvantes de secagem, como as maltodextrinas, que reduzem sua higroscopicidade. O presente estudo envolveu uma tentativa de substituição (total ou parcial) de maltodextrinas (MD) por goma de cajueiro (GC), um polissacarídeo semelhante à goma arábica, muito abundante no Nordeste brasileiro, mas ainda pouco utilizada. O objetivo do trabalho foi avaliar o impacto de duas variáveis do processo de atomização - proporção adjuvante de secagem/ sólidos de caju (2:1-5:1) e grau de substituição de MD por GC (0-100%), segundo um delineamento composto central - sobre a retenção de ácido ascórbico e as propriedades físicas (higroscopicidade e fluidez) e solubilidade de suco de caju atomizado. A retenção de ácido ascórbico durante a atomização foi favorecida por maiores proporções adjuvante de secagem/sólidos de caju (AS/SC) e maior grau de substituição de MD por GC. A goma de cajueiro mostrou-se um material bastante promissor a ser utilizado como adjuvante de secagem. As condições de processo consideradas como as mais adequadas foram as seguintes: proporção AS/SC, 5:1, com substituição de MD por GC em pelo menos 50%.
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Micropartículas poliméricas contendo fármacos antivirais: desenvolvimento, caracterização físico-química, avaliação do perfil de liberação in vitro e da atividade antiviralReolon, Jéssica Brandão January 2016 (has links)
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Previous issue date: 2016 / O herpesvírus simples (HSV) é um importante problema de saúde pública em vários países provocando ulceração genital. Dentre o arsenal terapêutico para o tratamento da infecção por HSV destaca-se o aciclovir (ACV). No entanto, este apresenta limitações no seu uso como um tempo de meia-vida curto e uma baixa solubilidade aquosa. A curcumina (CUR) é um composto natural que vem demonstrando diversas atividades terapêuticas, dentre estas a atividade antiviral, porém o seu uso por via oral também é comprometido pela baixa solubilidade em água. A encapsulação em micropartículas poliméricas (MPs) é uma abordagem farmacotécnica que podem superar as dificuldades do uso terapêutico destes dois compostos. Em vista disto, o presente trabalho visou desenvolver e caracterizar MPs pelo método de aspersão compostas por HPMC e Eudragit® RS100 como materiais poliméricos, além de manitol como adjuvante de secagem. Os resultados demonstraram que o método de preparo por aspersão (spray drying) apresentou um rendimento em torno de 50% para todas as formulações desenvolvidas, mostrando um fluxo tecnológico mais vantajoso para as partículas sem manitol. O doseamento demonstrou teores de 82 a 99% e de 81 a 94%, para ACV e CUR, respectivamente. A análise granulométrica mostrou micropartículas de tamanho micrométrico entre 8,7 e 15,3 μm. A análise morfológica evidenciou o formato esférico e confirmou o resultado das análises de tamanho. A espectroscopia na região do infravermelho mostrou uma sobreposição dos espectros obtidos pelos componentes isolados indicando boa compatibilidade entre os materiais. O perfil de liberação in vitro permitiu observar que as MPs foram capazes de controlar a liberação e melhorar a solubilidade dos compostos, destacando-se, neste quesito, as MPs compostas por HPMC. A avaliação preliminar da atividade antiviral in vitro demonstrou que a associação de ACV e CUR possui um efeito sinérgico frente ao vírus BoVH-1, sendo que as MPs foram capazes de potencializar este efeito. Neste contexto, as MPs mostraram-se sistemas promissores para a veiculação de ACV e CUR por via oral, com elevado potencial para constituir um tratamento alternativo para o herpes viral. / The herpes simplex virus (HSV), also known as human herpes virus, infects humans causing mainly genital and labial ulcerations. Among the drugs available for the treatment of HSV infection the acyclovir (ACV) is an effective antiviral drug. However this drug presents limitations in its use due to the short half-life and low water solubility. Curcumin (CUR) has demonstrated several therapeutic activities, including antiviral activity, but the oral administration of this natural compound is also compromised by low solubility. The polymeric microparticles (MP) are a pharmacotechnical approach that modifies the pharmacokinetics of the compounds and offers a possibility to overcome the difficulties of the therapeutic use. In view of this, this study aimed to develop MPs by spray drying method composed of HPMC and Eudragit® RS100 as polymeric materials, and mannitol as drying material. The results showed a yield around 50% for all developed formulations and a better technological flow rate for the particles without mannitol. The assay showed levels 82-99 and 81% to 94%, to ACV and CUR, respectively. The particle size analysis showed microparticles micrometric size between 8.7 and 15.3 micrometers. Morphological analysis showed the spherical shape and confirmed the results of size analysis. Spectroscopy in the infrared showed an overlap of the spectra obtained by the individual components indicating good compatibility between the materials. The in vitro release profile observed that the PMs were able to control the release and improved the solubility of the compounds, especially when composed of HPMC. Besides, an in vitro preliminary assessment of antiviral activity demonstrated that the combination of ACV and CUR presented a synergistic effect against BoVH-1 virus, and the MPs were able to enhance this effect. The MPs showed to be promising systems for the oral administration of ACV and CUR and could be an improved alternative treatment for viral herpes.
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Micropartículas contendo pantoprazol sódico: desenvolvimento tecnológico, produção em escala piloto e avaliação biológica / Micropartcles contaning sodium pantoprazole : technological development, scale up and biological activityRaffin, Renata Platcheck January 2007 (has links)
Micropartículas contendo pantoprazol foram preparadas e caracterizadas a fim de se obter sistemas multiparticulados gastro-resistentes. O trabalho foi delineado buscando-se a melhor técnica de preparação das micropartículas, assim como o estudo do processo, aumento de escala e avaliação biológica. A metodologia analítica para quantificação do pantoprazol nas micropartículas foi desenvolvida e validada. O método mostrou-se seletivo, linear, preciso e exato. A estabilidade do pantoprazol em tampão fosfato pH 7,4 foi avaliada para verificar a viabilidade da utilização deste tampão como meio de dissolução. O pantoprazol apresentou-se estável durante 6 h e considerado adequado para estudos de dissolução. A primeira técnica utilizada na preparação de micropartículas foi a evaporação de solvente, utilizando uma emulsão O/O. O polímero utilizado foi Eudragit® S100. As micropartículas apresentaram diâmetro de 56 μm e, segundo análises de DSC e IV, o fármaco apresentou-se molecularmente disperso no polímero. As micropartículas apresentaram atividade anti-ulcerogênica em modelo de ulceração gástrica em ratos por etanol, enquanto a solução aquosa de pantoprazol não apresentou atividade. Estas micropartículas foram comprimidas e permaneceram intactas no interior dos comprimidos. Quanto à proteção do pantoprazol em meio ácido, 61 % da quantidade inicial do fármaco permaneceram estáveis após 30 min em meio ácido. Uma segunda formulação utilizando a mesma técnica foi preparada coma a adição de poli(ε-caprolactona) à formulação de Eudragit® S100. O objetivo da inclusão do segundo polímero foi a obtenção de uma blenda capaz de promover liberação controlada do pantoprazol e ao mesmo tempo conferir gastro-resistência. Esta formulação também apresentou atividade anti-ulcerogênica in vivo. Os comprimidos contendo estas micropartículas apresentaram liberação controlada e gastroresistência. A segunda técnica avaliada no desenvolvimento de micropartículas contendo pantoprazol foi a secagem por aspersão. Micropartículas contendo Eudragit® S100 foram produzidas e apresentaram bom rendimento, eficiência de encapsulação e estabilização do pantoprazol em meio ácido. As micropartículas foram avaliadas quanto a permeação intestinal utilizando modelo de intestino invertido. A permeação intestinal foi diretamente proporcional à liberação em tampão fosfato pH 7,4, estabelecendo uma correlação de nível A. Devido a esses fatores, estas micropartículas foram selecionadas para preparação em escala piloto. Diferentes condições operacionais foram testadas e o diâmetro médio das partículas xxiv variou entre 6.7 e 24.5 μm, influenciado pela concentração inicial de sólidos. As condições operacionais que produziram micropartículas com maior gastroresistência foram selecionadas para estudo de estabilidade. As micropartículas apresentaram-se estáveis por 6 meses em condições aceleradas de armazenamento e não adsorveram umidade ao longo do tempo. A avaliação in vivo demonstrou a atividade anti-ulcerogênica desta formulação. No entanto, a formulação apresentou baixa densidade e fluxo pobre, dificultando a granulação e compressão. A forma farmacêutica desenvolvida foram aglomerados ou soft pellets, contendo micropartículas de pantoprazol e um excipiente de manitol e lecitina preparado por spray-drying. Os aglomerados apresentaram adequadas características de fluxo e rápida desintegração não afetando a gastro-resistência das micropartículas. A técnica de spray-drying também foi utilizada com uma blenda de Eudragit® S100 e HPMC, também visando uma liberação controlada do pantoprazol. As micropartículas apresentaram alta eficiência de encapsulação e também reduziram a formação de úlceras gástricas por etanol em ratos. Os comprimidos contendo micropartículas preparadas com a blenda apresentaram mais de 90 % de estabilização em meio ácido. Este processo também foi escalonado e as melhores condições operacionais determinadas. O processo foi reprodutível em relação ao diâmetro, densidade, eficiência de encapsulação e gastro-resistência. Esta formulação foi estável por 6 meses a 40 °C e 75 % de umidade. As quatro formulações descritas neste trabalho foram testadas quanto à estabilização do pantoprazol frente à luz UVC. O pantoprazol demonstrou ser fotoinstável tanto em solução metanólica como sólido e apenas as micropartículas preparadas com Eudragit® S100 aumentaram a fotoestabilidade do pantoprazol. Baseado no conjunto de resultados, os aglomerados contendo micropartículas de Eudragit® S100 foram selecionadas para serem testadas quanto a sua farmacocinética, em comparação com o comprimido comercial de referência. Os aglomerados demonstraram ser mais rapidamente absorvidos, reduzindo o Tmax de 90 para 43 min, mantendo mesma biodisponibilidade oral. Desta forma, podemos concluir que o pantoprazol foi microencapsulado com sucesso e as micropartículas aumentaram a estabilidade do fármaco em meio ácido e frente à luz, além de reduzir o tempo para atingir a concentração máxima do mesmo. / The aim of the thesis is to develop, characterize and evaluate two drug delivery systems containing gastro-resistant pantoprazole microparticles, one for the prompt dissolution and the other one for controlled release of pantoprazole. First, an analytical method was developed and validated for the quantification of sodium pantoprazole by HPLC. The stability of pantoprazole in phosphate buffer at pH 7.4 was also evaluated during 22 days. The results showed that the method was specific, linear, precise and exact. Pantoprazole was stable in phosphate buffer pH 7.4 for 6 h. Then, the solvent evaporation technique was applied in the preparation of gastroresistant pantoprazole-loaded microparticles using an O/O emulsion. Furthermore, tablets containing the microparticles were also investigated. Microparticles presented spherical and smooth morphologies and they remained intact in the inner surface of tablets. DSC and IR analyses showed that pantoprazole was physically and molecularly dispersed in the polymer. In vivo anti-ulcer evaluation showed that the microparticles were able to protect the rat stomachs against ulcer formation by ethanol, while the drug aqueous solution did not present activity. Concerning the acid protection, tablets showed a satisfactory drug protection in acid medium (61 % after 30 min). As a second formulation, microparticles of poly(ε-caprolactone) blended with Eudragit® S100 were prepared in order to provide controlled release and gastroresistance. This formulation showed in vivo protection of stomachs against ulceration caused by ethanol in rats. These microparticles were tableted and the tablets demonstrated slower drug release and higher acid protection than the microparticles before tableting. The spray drying technique was also used to prepare pantoprazoleloaded microparticles. Microparticles containing pantoprazole and Eudragit S100® presented high encapsulation efficiency and good stabilization in acid medium. Microparticles prevented ulceration by ethanol in vivo. These microparticles showed more adequate characteristics for the preparation of a drug delivery system than the one prepared by solvent evaporation. The physical characteristics of pantoprazole microparticles produced in different spray dryers and operational conditions were investigated. In all conditions tested it was possible to obtain powders that presented spherical shape microparticles, with mean sizes from 6.7 to 24.5 μm. The size was xxvi mainly affected by the initial feed concentration (2.2 or 6.6% w/w). All powders presented very poor flow. Under accelerated conditions of storage, the selected microparticles were stable for 6 months. The microparticles couldn’t be tableted and then, the microparticles were agglomerated with mannitol/lecithin powder. The agglomerates presented good technological properties and did not influence the drug release and the gastro-resistance of the pantoprazole microencapsulated. The spray drying technique was also used to prepare microparticles aiming to provide gastroresistance and to control the drug release, using a blend of Eudragit S100® and HPMC. DSC analyses showed that the drug is molecularly dispersed in the microparticles, and in vivo anti-ulcer evaluation demonstrated that microparticles were effective in protecting stomach against ulceration. In vitro gastro-resistance study showed that the microparticles stabilized pantoprazole in 62.0 % and tablets containing the microparticles in 97.5 % and provided a controlled release of the drug. This formulation was also studied in different scales of production and spray-drier designs. The microparticles were produced in different spray-driers and operational conditions at laboratory and pilot scales. The microparticles produced with two fluid nozzle atomizer and 196 kPa were prepared in three consecutive days for the process validation. The powders showed reproducible diameter, low polydispersity, similar bulk densities, encapsulation efficiency and gastro-resistance. These microparticles were evaluated for their accelerate stability. The microparticles presented less than 5 % of degradation after 180 days at 40 °C and 75 % of RH. These same microparticles were agglomerated using mannitol/lechitin spray-dried as excipient. Different amounts of lecithin and mannitol were used, but only one formulation did not alter the pantoprazole release from the microparticles, as well as the gastro-resistance. The four different formulations of microparticles characterized in this study were tested for the stabilization of pantoprazol under UVC light. Only the microparticles prepared with Eudragit® S100 improved the drug photostability. Based on the results, the agglomerates containing microparticles prepared by spray-drying with Eudragit® S100 were selected for the pharmacokinetics study in dogs. The agglomerates presented similar AUC than the reference tablet, but reduced the Tmax. In conclusion, pantopazole-loaded microparticles were successfully prepared and the stability of pantoprazol in acid medium and under light was improved. Furthermore, the time to peak plasma was reduced.
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Desenvolvimento de sistemas magn?ticos com potencialidades terap?uticas para vetoriza??o de f?rmacosSilva, Erica Lira da 31 March 2010 (has links)
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Previous issue date: 2010-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Magnetic targeting is being investigated as a means of local delivery of drugs, combining precision, minimal surgical intervention, and satisfactory concentration of the drug in the target region. In view of these advantages, it is a promising strategy for improving the pharmacological response. Magnetic
particles are attracted by a magnetic field gradient, and drugs bound to them can be driven to their site of action by means of the selective application of magnetic field on the desired area. Helicobacter pylori is the commonest chronic bacterial infection. The treatment of choice has commonly been based upon a triple therapy combining two antibiotics and an anti-secretory agent.
Furthermore, an extended-release profile is of utmost importance for these formulations. The aim of this work was to develop a magnetic system containing the antibiotic amoxicillin for oral magnetic drug targeting. First, magnetic particles were produced by coprecipitation of iron salts in alkaline medium. The second step was coating the particles and amoxicillin with Eudragit? S-100 by spray-drying technique. The system obtained demonstrated through the characterization studies carried out a possible oral drug delivery system, consisting in magnetite microparticles and amoxicillin, coated with a polymer acid resistant. This system can be used to deliver drugs to the stomach for treatment of infections in this organ. Another important finding in this work is that it opens new prospects to coat magnetic microparticles by the technique of spray-drying. / A vetoriza??o magn?tica tem sido investigada como uma forma de entrega local de f?rmacos combinando precis?o, m?nima interven??o cir?rgica e concentra??o satisfat?ria do f?rmaco na regi?o de interesse. Part?culas magn?ticas s?o atra?das a partir da aplica??o de um campo magn?tico e f?rmacos associados a essas part?culas podem ser direcionados ao seu s?tio de a??o atrav?s de uma aplica??o seletiva do campo na regi?o de interesse. Helicobacter pylori ? a mais comum causa de infec??o bacteriana cr?nica no est?mago. O tratamento padr?o ? a tripla terapia oral contendo dois antibi?ticos e um inibidor da bomba de pr?tons. Sendo assim, um perfil de libera??o prolongada ? de suma import?ncia para essas formula??es. O objetivo deste
trabalho foi desenvolver um sistema magn?tico com potencial emprego na vetoriza??o de antibi?tico por via oral. Inicialmente, part?culas magn?ticas foram produzidas por co-precipita??o de sais de ferro em meio alcalino. Em seguida, as part?culas foram revestidas a partir da dispers?o da suspens?o magn?tica em uma solu??o contendo o pol?mero dissolvido e a amoxicilina, e ent?o submetido ? secagem por aspers?o (spray-drying). Atrav?s das
caracteriza??es realizadas p?de-se verificar a obten??o de um potencial sistema para vetoriza??o de f?rmacos por via oral contendo micropart?culas de magnetita e amoxicilina revestidos por um pol?mero gastro-resistente. Adicionalmente, um importante aspecto nesse trabalho ? a abertura de novas
perspectivas para o revestimento de micropart?culas magn?ticas atrav?s da t?cnica de spray-drying.
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ProduÃÃo de extrato enzimÃtico proteolÃtico por Aspergillus oryzae ccbp001 em reator instrumentado por fermentaÃÃo semi-sÃlida / Extract of enzymatic production by Aspergillus oryzae proteolytic ccbp001 instrumented reactor in solid-state fermentationAdriana Crispim de Freitas 25 February 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A produÃÃo de enzimas por fermentaÃÃo semi-sÃlida (FSS) à influenciada por diversos fatores de cultivo que afetam o crescimento microbiano e a produÃÃo de metabÃlitos. O estudo de fatores como aeraÃÃo e umidade do ar torna-se indispensÃvel para a otimizaÃÃo deste bioprocesso. Neste contexto, o presente trabalho teve como objetivo avaliar a produÃÃo de protease pelo fungo Aspergillus oryzae CCBP001 por FSS em biorreator de colunas. A FSS para a produÃÃo de protease utilizando o fungo filamentoso A. oryzae CCBP 001 ocorreu em condiÃÃes dinÃmica e estÃtica, visando observar o mÃtodo que apresentou a maior produÃÃo. Para tanto foram testados os resÃduos agroindustriais: torta de canola, torta de girassol, farelo de trigo, pelÃcula da amÃndoa de caju e farelo de algodÃo como substrato, observando o perfil de produÃÃo em funÃÃo de diferentes atividades de Ãgua (Aw) iniciais obtidas pela adiÃÃo de distintos volumes de Ãgua para umidificaÃÃo. A produÃÃo de protease em reator de colunas nas condiÃÃes otimizadas foi comparada com a produÃÃo em Erlenmeyer, durante dez dias. Foram avaliados procedimentos para recuperar, identificar, concentrar, e estocar o extrato enzimÃtico produzido. Para a concentraÃÃo do extrato enzimÃtico produzido realizou-se estudo de secagem em âspray dryerâ e acompanhou-se o tempo de estocagem do extrato seco durante 90 dias. Com os resultados foi possÃvel selecionar a torta de canola como o substrato onde apresentou uma produÃÃo 33% superior aos demais substratos testados. No estudo das condiÃÃes operacionais em reator de colunas foi possÃvel avaliar a influÃncia da vazÃo do ar, umidade relativa do ar e umidade do substrato na produÃÃo de protease. A utilizaÃÃo de glicose, maltodextrina e carboximetilcelulose como adjuvantes se mostraram eficientes com relaÃÃo à manutenÃÃo da atividade de protease durante o processo de secagem utilizando âspray dryerâ, onde foi possÃvel obter um produto seco com baixos valores de umidade e Aw, importante para o processo de estocagem do extrato enzimÃtico. A secagem por atomizaÃÃo do extrato enzimÃtico possibilitou concentrar e estocar a enzima. / Enzyme production by solid state fermentation (SSF) is influenced by several factors that affect crop growth and production of microbial metabolites. The study of factors such as aeration and moisture in the air becomes indispensable for this bioprocess optimization. In this context, the present study aimed to assess the protease production by Aspergillus oryzae CCBP001 by FSS bioreactor columns. The FSS for the production of protease using the filamentous fungus A. oryzae CCBP 001 occurred in dynamic and static conditions in order to observe the method with the highest production. Therefore, tested the agroindustrial waste: canola cake, sunflower cake, wheat bran, almond cashew film and cottonseed meal as substrate, observing the production profile for different water activity (Aw) obtained by initial adding different volumes of water for humidification. Protease production in reactor columns in the optimized conditions was compared to production in flasks for 10 days. Evaluated procedures to recover, identify, focus and store the enzyme extract produced. For the concentration of the enzyme extract produced a study was conducted in dry "spray dryer" and followed up the storage time of the dry extract for 90 days. From the results it was possible to select the canola cake as the substrate where it presented a production 33% higher than the other substrates tested. In the study of operating conditions in reactor columns was possible to evaluate the influence of air flow, air humidity and substrate moisture in protease production. The use of glucose, maltodextrin and carboxymethylcellulose as adjuvants proved to be efficient with regard to maintenance of protease activity during the drying process using a "spray dryer", where it was possible to obtain a dry product with low values of humidity and Aw important for the storage process of enzyme extract. Spray drying of the enzyme extract and concentrate stockpile allowed the enzyme.
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Aproveitamento dos subprodutos de vinificação da uva Bordô (Vitis labrusca) para obtenção de pigmentos com propriedades funcionais / Use of vinification byproducts of Bordo grape (Vitis labrusca) to obtain pigments with functional propertiesVolnei Brito de Souza 04 March 2013 (has links)
O objetivo deste trabalho foi produzir pigmentos em pó a partir dos subprodutos de vinificação da uva tinta, variedade Bordô (Vitis labrusca), através da secagem em spray dryer utilizando maltodextrina como agente carreador. Foram estudados os efeitos das condições de processo sobre algumas propriedades físico-químicas, além da estabilidade e da atividade biológica do material obtido. Extratos etanólicos das cascas e sementes da uva foram obtidos e concentrados até um terço do volume inicial. Este extrato foi então misturado com o agente carreador maltodextrina 10 DE nas concentrações de 10, 20 ou 30% e atomizado em spray dryer, com vazão de alimentação de 44 mL/min e temperaturas do ar de entrada de 130, 150 ou 170°C, num total de nove ensaios. Além disso, foi obtida uma amostra de extrato concentrado liofilizado, sem a presença do agente carreador, para efeito de comparação. Avaliou-se o rendimento do processo de atomização; e para as amostras obtidas determinou-se o teor de umidade, retenção de antocianinas, higroscopicidade e solubilidade em água, a fim de verificar a influência das condições de processo sobre essas características. Estas amostras também foram avaliadas quanto à morfologia, distribuição do tamanho de partículas e isotermas de sorção de umidade. Todas as amostras obtidas (atomizadas e liofilizada) foram avaliadas quanto à cor instrumental, espectroscopia de infravermelho, estabilidade durante a estocagem, presença de compostos bioativos (fenólicos, flavonóides, antocianinas e proantocianidinas), além de atividade antioxidante, antimicrobiana e de inibição da arginase de Leishmania. As condições de processo avaliadas (temperatura de secagem e concentração de agente carreador) tiveram forte influência nas características estudadas. O teor de umidade, a retenção de antocianinas, a morfologia e o tamanho das partículas, foram bastante influenciados pela temperatura de secagem e pela concentração de agente carreador, enquanto que a higroscopicidade sofreu maior influência da concentração de agente carreador. Esse parâmetro também apresentou grande influência nas isotermas de sorção de umidade das amostras. Não houve grande interferência do processo de secagem na composição química do material obtido, evidenciada pelos espectros de infravermelho. Quanto à avaliação da estabilidade durante a estocagem, foi observado que as amostras contendo maltodextrina conservaram mais as antocianinas e a cor, quando comparadas com as amostras sem carreador e os extratos líquidos, indicando, que o processo de secagem e a presença do carreador, promoveram um efeito protetor aos compostos e sua cor. Todas as amostras apresentaram altos teores de flavonóides totais, antocianinas, proantocianidinas e elevados valores de atividade antioxidante variando de 314,06 a 441,04 µmolesTE/g de extrato seco pelo método DPPH e de 993,32 a 1138,68 µmolesTE/g de extrato seco pelo método FRAP. Apresentaram atividade antimicrobiana principalmente contra Staphylococcus aureus e Listeria monocytogenes. Além disso, tiveram grande capacidade de inibir a enzima arginase de Leishmania com porcentagem de inibição variando de 54,60 a 83,43%. Os resultados encontrados sugeriram que o processo de secagem em spray dryer com maltodextrina, dos extratos obtidos dos subprodutos da uva Bordô, produziu pós com diversas características interessantes, como baixa higroscopicidade, alta solubilidade e estabilidade, além de grande potencial biológico. Tais resultados evidenciam que este subproduto da indústria vinícola pode ser aproveitado como fonte natural de ingredientes funcionais. / The aim of this work was to produce powder pigments from grape byproducts of Bordo variety (Vitis labrusca) by spray drying using maltodextrin as carrier agent. The effects of process conditions on some physicochemical properties, stability and biological activity of the product were studied. Ethanol extracts were obtained from grape pomace (skins and seeds) and concentrated to one-third the initial volume. This extract was then mixed with the carrier agent 10 DE maltodextrin at concentrations of 10, 20 or 30% and atomized in a spray dryer, with feed flow rate of 44 mL/min and inlet drying air temperatures of 130, 150 or 170°C a total of nine tests. In addition, a sample of freeze-dried concentrated extract without carrier agent was obtained for comparison. It was evaluated process yield and the samples obtained were initially evaluated for moisture content, anthocyanins retention, hygroscopicity and solubility in water, in order to verify the influence of process conditions on these characteristics. These samples were also evaluated for morphology, particle size distribution and moisture sorption isotherms. All samples (spray-dried powders and freeze-dried extract) were evaluated for instrumental color, infrared spectroscopy, stability during storage, presence of bioactive compounds (phenols, flavonoids, anthocyanins and proanthocyanidins) plus antioxidant activity, antimicrobial activity and inhibition of Leishmania arginase. Process conditions evaluated (inlet drying air temperature and carrier agent concentration) had a strong influence on the characteristics studied. The moisture content, anthocyanin retention, morphology and particle size of the samples were strongly influenced by drying temperature and carrier agent concentration while the hygroscopicity suffered greater influence of the carrier agent concentration. The concentration of carrier agent also had great influence on the moisture sorption isotherms of the samples. There was no significant interference of the drying process on the chemical composition of the material evidenced by infrared spectroscopy. Regarding the evaluation of stability during storage, it was observed that the samples containing maltodextrin, retained much more anthocyanins and original color when compared with the sample without a carrier or liquid extracts, indicating both, the drying process and the presence of carrier, promoted a protective effect to the compounds and its color. All samples showed high levels of flavonoids, anthocyanins, proanthocyanidins and high levels of antioxidant activity ranging from 314.06 to 441.04 µmolTE/g of extract (dry weight), by DPPH and 993.32 to 1138.68 µmolTE/g of extract (dry weight) by FRAP method. Most samples showed antimicrobial activity against Staphylococcus aureus and Listeria monocytogenes. Moreover, had great ability to inhibit the enzyme arginase of Leishmania with inhibition percentage ranging from 54.60 to 83.43%. The results suggest that the drying process of Bordo grape pomace extracts in a spray dryer with maltodextrin, produced powders with various interesting characteristics such as low hygroscopicity, high solubility and stability, and large biological potential. This shows that this byproduct of wine industry can be used as a natural source of functional ingredients.
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