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1.
AAPS PharmSciTech ; 21(5): 143, 2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-32424702

RESUMEN

This work aims to improve the functionality of Rosmarinus officinalis L. (rosemary) polyphenols by encapsulation in an optimized proliposome formulation. A 23 Box-Wilson central composite design (CCD) was employed to determine lone and interaction effects of composition variables on moisture content (Xp); water activity (Aw); concentration and retention of rosemary polyphenols-rosmarinic acid (ROA), carnosol (CAR), and carnosic acid (CNA); and recovery of spray-dried proliposomes (SDP). Processing conditions which generate proliposomes with optimum physicochemical properties were determined by multi-response analysis (desirability approach). Antioxidant and antifungal activities were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH•) sequestering and minimum inhibitory concentration (MIC)/minimum fungicidal concentration (MFC) assays, respectively. SDP exhibited high polyphenol retention, ranging from 62.0 to 100.0% w/w, showing dependence on composition variables and polyphenol lipophilicity. SDP recovery ranged from 20.1 to 45.8%, with Xp and Aw of 1.7 ± 0.14-2.5 ± 0.23% w/w and 0.30 ± 0.004-0.47 ± 0.003, respectively, evidencing product with good chemical and microbiological stability. Optimum liposomal composition was determined, namely, lipid concentration (4.26% w/w), lyophilized extract (LE) concentration (4.48% w/w), and drying aid:(lipid+extract) ratio (7.55% w/w) on wet basis. Relative errors between experimental and predicted values for SDP properties showed concurrence for all responses except CAR retention, being 22% lower. SDP showed high antioxidant activity with IC50 of 9.2 ± 0.2 µg/mL, superior to results obtained for LE (10.8 µg/mL) and butylated hydroxytoluene (BHT), a synthetic antioxidant (12.5 µg/mL). MIC and MFC against Candida albicans (ATCC1023) were 312.5 µg/mL and 1250 µg/mL, respectively, a moderate antimicrobial activity for phytochemical-based products. SDP is shown as a veritable tool to encapsulate hydrophilic and lipophilic rosemary polyphenols generating a product with optimal physicochemical and biological properties.


Asunto(s)
Liposomas/química , Polifenoles/química , Rosmarinus/química , Antifúngicos/farmacología , Antioxidantes/farmacología , Candida albicans/efectos de los fármacos , Cápsulas , Desecación , Composición de Medicamentos , Liofilización , Humanos , Lípidos/química , Pruebas de Sensibilidad Microbiana , Hojas de la Planta/química , Polifenoles/administración & dosificación , Polifenoles/farmacología , Agua/análisis
2.
Int J Food Sci Nutr ; 69(8): 995-1002, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29482377

RESUMEN

This study aims (i) to verify expression of the UCPs, PLIN1, PPARG2, and ADRB3 genes in the abdominal subcutaneous adipose tissue of obese women at baseline and after 8 weeks of supplementation with decaffeinated green tea extract, and (ii) to associate findings with clinical parameters. This is a longitudinal study during which 11 women with obesity grade III were submitted to supplementation with 450 mg of (-)-epigallocatechin gallate (EGCG) (intervention group); the control group consisted of 10 eutrophic women. Anthropometric parameters [weight, height, and body mass index (BMI)], resting metabolic rate (RMR, measured by indirect calorimetry), and gene expression (measured by real-time PCR, RT-qPCR) were determined before and after supplementation. After 8 weeks, clinical parameters and UCP1, PLIN1, PPARG2, and ADRB3 expression remained unaltered in the intervention group (p > .05). Genetic analysis also showed that the UCP3 gene was upregulated (p = .026), but its upregulation did not promote weight loss.


Asunto(s)
Tejido Adiposo/metabolismo , Obesidad/terapia , Té/química , Proteína Desacopladora 3/metabolismo , Pérdida de Peso , Adolescente , Adulto , Metabolismo Basal , Índice de Masa Corporal , Catequina/análogos & derivados , Catequina/farmacología , Suplementos Dietéticos , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Obesidad/genética , PPAR gamma/genética , PPAR gamma/metabolismo , Perilipina-1/genética , Perilipina-1/metabolismo , Extractos Vegetales/farmacología , Receptores Adrenérgicos beta 3/genética , Receptores Adrenérgicos beta 3/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 3/genética , Regulación hacia Arriba , Adulto Joven
3.
J Microencapsul ; 32(1): 16-21, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25198912

RESUMEN

Two simple procedures for the preparation of magnetic chitosan enzyme microparticles have been investigated and used for the immobilisation of endophytic fungus Cercospora kikuchii lipase as model enzyme. In the first case, lipase was entrapped in Fe3O4-chitosan microparticles by cross-linking method, while in the second case magnetic immobilised derivatives were produced using spray drying. Immobilised enzymes showed high enzyme activity retention and stability during storage without significant loss of activity. Glutaraldehyde Fe3O4-chitosan powders presented a higher lipase activity retention and storage stability than the others preparations. However, the immobilised derivatives produced by cross-linking showed higher enzyme activity after reuse cycles. The results proved that the magnetic Fe3O4-chitosan microparticles are an effective support for the enzyme immobilisation since the immobilised lipase showed best properties than the free form.


Asunto(s)
Ascomicetos/enzimología , Quitosano/química , Enzimas Inmovilizadas/química , Óxido Ferrosoférrico/química , Proteínas Fúngicas/química , Lipasa/química
4.
Restor Dent Endod ; 49(1): e9, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38449495

RESUMEN

Objectives: This study aimed to evaluate the effect of pomegranate solution (Punica granatum) on eroded dentin through antioxidant action, shear bond strength (SBS) and interface morphology. Materials and Methods: The 10% pomegranate peel extract was prepared by the lyophilization method. Punicalagin polyphenol was confirmed by high-performance liquid chromatography. Antioxidant activity was evaluated by capturing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. For the SBS, 48 dentin fragments were divided into sound or eroded, and subdivided according to the pretreatment (n = 12): water or P. granatum. The surfaces were restored with self-etch adhesive and a bulk-fill resin (Ecosite; DMG). The SBS was done immediately (24 hours) and after thermal cycling + water storage (12 months). For scanning electron microscopy, 48 dentin fragments (24 sound and 24 eroded) received the same treatments as for SBS (n = 6), and they were analyzed after 24 hours and 12 months. Results: The P. granatum had antioxidant action similar (p = 0.246) to the phenolic standard antioxidants. After 24 hours, eroded dentin had lower SBS than sound dentin (p < 0.001), regardless of the pretreatment. After 12 months, P. granatum maintained the SBS of sound dentin (13.46 ± 3.42 MPa) and eroded dentin (10.96 ± 1.90 MPa) statistically similar. The lowest values were found on eroded dentin treated with water (5.75 ± 1.65 MPa) (p < 0.001). P. granatum on eroded dentin caused peritubular demineralization and hybrid layer with resin tags. Conclusions: The pomegranate extract had antioxidant action and preserved the adhesive interface of the eroded dentin.

5.
J Microencapsul ; 30(7): 624-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23489014

RESUMEN

Microbial enzymes have been used for various biotechnological applications; however, enzyme stabilization remains a challenge for industries and needs to be considered. This study describes the effects of spray-drying conditions on the activity and stability of ß-fructofuranosidase from Fusarium graminearum. The extracellular enzyme ß-fructofuranosidase was spray dried in the presence of stabilizers, including starch (Capsul) (SC), microcrystalline cellulose (MC), trehalose (TR), lactose (LC) and ß-cyclodextrin (CD). In the presence of TR (2% w/v), the enzymatic activity was fully retained. After 1 year of storage, 74% of the enzymatic activity was maintained with the CD stabilizer (10% w/v). The residual activity was maintained as high as 80% for 1 h at 70°C when MC, SC and CD (5% w/v) stabilizers were used. Spray drying with carbohydrates was effective in stabilizing the F. graminearum ß-fructofuranosidase, improved enzymatic properties compared to the soluble enzyme and demonstrated a potential use in future biotechnology applications.


Asunto(s)
Fusarium/enzimología , beta-Fructofuranosidasa/metabolismo , Carbohidratos/química , Desecación , Estabilidad de Enzimas , Excipientes/química , Fusarium/química , beta-Fructofuranosidasa/química
6.
Polymers (Basel) ; 14(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36432987

RESUMEN

Since the SARS-CoV-2 pandemic, the interest in applying nanofibers t air filtration and personal protective equipment has grown significantly. Due to their morphological and structural properties, nanofibers have potential applications for air filtration in masks and air filters. However, most nanofiber membrane materials used for these purposes are generally non-degradable materials, which can contribute to the disposal of plastic waste into the environment. Hence, this work aims to produce polyvinyl alcohol (PVA) and chitosan (CS) biodegradable nanofibers with controlled morphology and structure via electrospinning. An experimental design was used to investigate the effects of the PVA|CS ratio and concentration on the properties of the electrospinning compositions and electrospun nanofiber mat. The electrospinning parameters were constant for all experiments: Voltage of 20 kV, a feed rate of 0.5 mL·h−1, and a distance of 10 cm between the needle and a drum collector. CS proved to be an efficient adjuvant to the PVA's electrospinning, obtaining a wide range of nanofiber diameters. Furthermore, 6.0% PVA and 1% CS were the best compositions after optimization with the response surface methodology, with a mean fiber diameter of 204 nm. The addition of biocide agents using the optimized condition was also investigated, using surfactants, citric acid, and pure and encapsulated essential oils of Lippia sidoides. Pure oil improved the material without enlarging the nanofiber sizes compared to the other additives. The nanofiber membranes produced have the potential to be used in air filtration or wound-dressing applications where biocidal activity is needed.

7.
3 Biotech ; 10(4): 177, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32226706

RESUMEN

The Aspergillus fumigatus CAS21 tannase was spray dried with ß-cyclodextrin, Capsul® starch, soybean meal, lactose, and maltodextrin as adjuvants. The moisture content and water activity of the products ranged from 5.6 to 11.5% and from 0.249 to 0.448, respectively. The maximal tannase activity was achieved at 40-60 ºC and pH 5.0-6.0 for the powders containing ß-cyclodextrin and Capsul® starch, which was stable at 40 ºC and 40-60 ºC for 120 min, respectively. For all the dried products, tannase retained its activity of over 80% for 120 min at pH 5.0 and 6.0. Salts and solvents influenced the activity of the spray-dried tannase. The activity of the spray-dried tannase was maintained when preserved for 1 year at 4 ºC and 28 ºC. Spray-dried tannase reduced the content of tannins and polyphenolic compounds of leather effluent and sorghum flour and catalyzed the transesterification reaction. The spray drying process stabilized the tannase activity, highlighting the potential of dried products for biotechnological applications.

8.
Braz. arch. biol. technol ; 63: e20190024, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1132186

RESUMEN

Abstract Pigments produced by submerged fermentation of three filamentous fungi isolated from Brazilian caves, namely Aspergillus keveii, Penicillium flavigenum, and Epicoccum nigrum, were submitted to spray drying in presence of the adjuvants maltodextrin, modified starch or gum arabic. Yellow fine powders with low moisture content and water activity, and high color retention (> 70%) were successfully generated with a high product recovery ratio (> 50%), independently of the adjuvant used. The dried products have enhanced stability and potential to might be used as a natural colorant in food and pharmaceutical applications.


Asunto(s)
Animales , Pigmentos Biológicos/biosíntesis , Almidón/biosíntesis , Hongos/metabolismo , Goma Arábiga , Maltosa/biosíntesis , Aspergillus , Brasil , Cuevas/microbiología , Hongos/clasificación , Maltosa/análogos & derivados , Modelos Teóricos
9.
Eur J Pharm Biopharm ; 55(3): 313-21, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12754006

RESUMEN

The present study was conducted in order to analyze the viability of the spouted bed process for application of a gastric-resistant coating to soft gelatin capsules. The variables investigated were: included angle of conical base, (gamma), the relation between the feed mass flow rate of the coating suspension and the feed mass flow rate of spouting gas (W(s)/W(g)); the ratio between the flow rate of the spouting gas and the flow rate at minimum spouting condition (Q/Q(ms)); the mass of capsules in the bed (M(0)), and the capsule's size. The product quality was measured by disintegration tests, traction x deformation tests, image analysis and by the evaluation of the coating mass distribution and shape factor variation during the coating operation. The experiments were performed in a spouted bed with a column diameter of 200 mm and included a conical base angle of 40 degrees. The best coating efficiency values were obtained for M(0)=300 g. Coating efficiency tended to increase with increasing W(s)/W(g) ratio. Disintegration tests showed that the gastric-resistant effect was obtained with a coating mass of 3.86 mg/cm(2). The shape factor increase during the coating operation. The capsule's coating mass distribution tended to maintain the original distribution.


Asunto(s)
Cápsulas/normas , Gelatina/normas , Comprimidos Recubiertos/normas , Tecnología Farmacéutica/normas , Cápsulas/síntesis química , Gelatina/síntesis química , Comprimidos Recubiertos/síntesis química , Tecnología Farmacéutica/instrumentación , Tecnología Farmacéutica/métodos
10.
Asian Pac J Trop Biomed ; 4(2): 90-6, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25182278

RESUMEN

Clove (Syzygium aromaticum) is one of the most valuable spices that has been used for centuries as food preservative and for many medicinal purposes. Clove is native of Indonesia but nowadays is cultured in several parts of the world including Brazil in the state of Bahia. This plant represents one of the richest source of phenolic compounds such as eugenol, eugenol acetate and gallic acid and posses great potential for pharmaceutical, cosmetic, food and agricultural applications. This review includes the main studies reporting the biological activities of clove and eugenol. The antioxidant and antimicrobial activity of clove is higher than many fruits, vegetables and other spices and should deserve special attention. A new application of clove as larvicidal agent is an interesting strategy to combat dengue which is a serious health problem in Brazil and other tropical countries. Pharmacokinetics and toxicological studies were also mentioned. The different studies reviewed in this work confirm the traditional use of clove as food preservative and medicinal plant standing out the importance of this plant for different applications.

11.
J Microbiol Biotechnol ; 24(2): 177-87, 2014 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-24196167

RESUMEN

Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (>150 µm), soy bean meal (SB), corn meal (<150 µm) (CM), and maltodextrin as drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.


Asunto(s)
6-Fitasa/metabolismo , Biopelículas/crecimiento & desarrollo , Desecación , Rhizopus/enzimología , Rhizopus/fisiología , Zea mays/metabolismo , Metabolismo de los Hidratos de Carbono , Concentración de Iones de Hidrógeno , Factores de Tiempo
12.
Braz. arch. biol. technol ; 57(4): 578-586, Jul-Aug/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-712932

RESUMEN

This work studied the immobilization of Cercospora kikuchii lipases on chitosan microparticles by chemical attachment on chitosan acetate microparticles activated by glutaraldehyde (CAM) added before or after the enzyme and physical adsorption on highly deacetylated chitosan hydrochloride microparticles (CHM). Lipases covalently immobilized on pre-activated CAM showed better performance retaining 88.4% of the enzymatic activity, with 68.2% of immobilization efficiency (IE). The immobilized enzyme retained an activity of about 53.5 % after five reuses, using p-NPP as substrate. Physical adsorption of lipase onto highly deacetylated CHM showed 46.2 % of enzymatic activity and 28.6% of IE. This immobilized derivative did not lose activity up to 80 days of storage at 4°C, while lipases immobilized on pre-activated CAM maintained its activity up to 180 days at same conditions. Taken together the results indicate that chitosan microparticles provide an optimal microenvironment for the immobilized enzyme to maintain good activity and stability.

13.
Braz. j. pharm. sci ; 45(2): 209-218, Apr.-June 2009. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-525897

RESUMEN

Two distinct drying methods (spouted bed and spray drying) were used for production of dried extracts of Bauhinia forficata Link (Leguminosae, Caesalpinoideae). High-quality powder products in terms of physical and chemical properties were obtained. HPLC fingerprints revealed that the chromatographic profiles of flavonoid compounds present in the dried extract did not change significantly, due to drying. In general, the spouted bed drying caused a degradation of total flavonoids than was lower than that of the spray drying. Antioxidant properties of the dried extract, examined by their radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPHò) and inhibition of lipid peroxidation induced by Fe+2 assays (LPO), confirmed their antioxidant potential. The slight reduction in scavenging activity of the dried extracts may be associated with the occurrence of oxidative reactions, decomposition or losses of thermolabile compounds, induced by the heat.


Neste trabalho foram utilizados dois distintos secadores (leito de jorro e spray dryer) para a produção de extratos secos de Bauhinia forficata Link (Leguminosae, Caesalpinoideae) obtendo-se um produto seco com elevada qualidade em termos de suas propriedades físicas e químicas. Análises qualitativas obtidas por CLAE revelam que os perfis cromatográficos dos compostos flavonóides presentes nos extratos secos não apresentaram significativas mudanças durante a secagem quando comparados aos perfis obtidos para os extratos concentrados. Em geral, a secagem por leito de jorro acarreta menores perdas dos flavonóides totais do que a secagem em spray drying. A atividade antioxidante dos extratos secos foi examinada pelos métodos de (DPPHò) e peroxidação lipídica induzida por Fe+2 (LPO). Uma pequena redução na atividade sequestradora de radicais livres observada para os extratos secos pode ser associada com a ocorrência de reações oxidativas, decomposição e/ou perdas de compostos termolábeis induzidas pelo calor.


Asunto(s)
Antioxidantes/uso terapéutico , Bauhinia/fisiología , Extractos Vegetales/química , Fenómenos Químicos , Flavonoides , Medicamento Fitoterápico
14.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 39(3): 299-307, jul.-set. 2003. ilus, tab, graf
Artículo en Portugués | LILACS | ID: lil-356344

RESUMEN

Apresenta-se nesse trabalho um estudo da viabilidade da aplicação de revestimento gastro-resistente em cápsulas gelatinosas duras pelo processo leito de jorro. As variáveis investigadas foram: a razão entre a vazão mássica de suspensão de revestimento alimentada pela vazão de gás introduzida ao sistema (`W IND. sï/ W . gï), a razão entre a vazão de ar de jorro pela vazão correspondente à condição de jorro mínimo (Q/`Q IND. jmï), massa inicial de cápsulas inseridas no equipamento (`M IND. 0ï) e o tamanho das cápsulas (T `IND. caps'). O processo e a qualidade do produto obtido foram analisados através da taxa de aumento de massa das cápsulas (KÕ), da eficiência de adesão durante a operação (n), ensaios de desintegração, ensaios de compressão e por microfotografias obtidas em microscópio eletrônico de varredura...


Asunto(s)
Cápsulas , Preparaciones Farmacéuticas , Comprimidos Recubiertos , Microscopía Electrónica de Rastreo/métodos , Calidad de los Medicamentos Homeopáticos
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