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1.
Food Chem ; 429: 136980, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37527600

RESUMO

Edible beef tallow (BT) has been widely used in Sichuan hotpot due to its unique flavor and texture. However, BT should not be consumed in excess caused by its trans-fatty acids and cholesterol issues. In this study, a BT substitute was prepared after enzymatic interesterification in a pilot-scale packed-bed reactor using soybean oil and fully hydrogenated palm oil (4:3, w/w) as feedstock. The products were characterized against BT in terms of fatty acid/triacylglycerol compositions, solid fat content, polymorphism, and melting/crystallization behaviors to select the most promising BT substitute. The optimal flow rate was 120 mL/min. Changes in volatile compounds during stir-frying and simmering were also investigated for Sichuan hotpots made with these two oils. The volatile compounds of BT substitute were similar to that of natural BT. The findings will contribute to expanding the base oil categories of Sichuan hotpot oils.


Assuntos
Carne Vermelha , Animais , Bovinos , Óleo de Soja/química , Triacetina/química , Ácidos Graxos/química , Cinética , Temperatura , Oxirredução , Esterificação , Projetos Piloto
2.
Molecules ; 26(24)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34946787

RESUMO

A water-free, ternary solvent mixture consisting of a natural deep eutectic solvent (NADES), ethanol, and triacetin was investigated concerning its ability to dissolve and extract curcumin from Curcuma longa L. To this purpose, 11 NADES based on choline chloride, acetylcholine, and proline were screened using UV-vis measurements. A ternary phase diagram with a particularly promising NADES, based on choline chloride and levulinic acid was recorded and the solubility domains of the monophasic region were examined and correlated with the system's structuring via light scattering experiments. At the optimum composition, close to the critical point, the solubility of curcumin could be enhanced by a factor of >1.5 with respect to acetone. In extraction experiments, conducted at the points of highest solubility and evaluated via HPLC, a total yield of ~84% curcuminoids per rhizome could be reached. Through multiple extraction cycles, reusing the extraction solvent, an enrichment of curcuminoids could be achieved while altering the solution. When counteracting the solvent change, even higher concentrated extracts can be obtained.


Assuntos
Curcuma/química , Curcumina/química , Curcumina/isolamento & purificação , Etanol/química , Triacetina/química , Acetilcolina/química , Colina/química , Prolina/química , Solubilidade
3.
Int J Biol Macromol ; 191: 79-91, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34537296

RESUMO

Lipase from Thermomyces lanuginosus (TLL) has been covalently immobilized on heterofunctional octyl-vinyl agarose. That way, the covalently immobilized enzymes will have identical orientation. Then, it has blocked using hexyl amine (HEX), ethylenediamine (EDA), Gly and Asp. The initial activity/stability of the different biocatalysts was very different, being the most stable the biocatalyst blocked with Gly. These biocatalysts had been utilized to analyze if the enzyme activity could decrease differently along thermal inactivation courses depending on the utilized substrate (that is, if the enzyme specificity was altered during its inactivation using 4 different substrates to determine the activity), and if this can be altered by the nature of the blocking agent and the inactivation conditions (we use pH 5, 7 and 9). Results show great changes in the enzyme specificity during inactivation (e.g., activity versus triacetin was much more quickly lost than versus the other substrates), and how this was modulated by the immobilization protocol and inactivation conditions. The difference in the changes induced by immobilization and inactivation were confirmed by fluorescence studies. That is, the functional and structural analysis of partially inactivated immobilized enzyme showed that their inactivation pathway is strongly depended on the support features and inactivation conditions.


Assuntos
Enzimas Imobilizadas/química , Eurotiales/enzimologia , Proteínas Fúngicas/química , Lipase/química , Microesferas , Sefarose/análogos & derivados , Ácido Aspártico/química , Enzimas Imobilizadas/metabolismo , Etilenodiaminas/química , Proteínas Fúngicas/metabolismo , Glicina/química , Lipase/metabolismo , Especificidade por Substrato , Sulfonas/química , Triacetina/química
4.
Carbohydr Polym ; 273: 118621, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34561016

RESUMO

Migration of additives is an important issue for proper application in food packaging. In this work, propionylated waxy and normal starch-based nanocomposites (PW-N and PN-N) with two different amylopectin content were immersed in distilled water, and structural changes and migration mechanism of plasticizer (triacetin) were discussed in detail. Results showed that when immersion time was prolonged to 150 h, small crystals of PN-N disappeared, and amorphous structures formed gradually in PW-N and PN-N. Exfoliated structures still remained in PW-N with prolonged immersion time, while exfoliated structures gradually formed from intercalated ones in PN-N, and the peak representing d001 (d-spacing) at q = 1.70 nm-1 faded. The migration mechanism of triacetin obeyed the first-order kinetic model and Fick's law; furthermore, in comparison with PW-N, PN-N showed a larger diffusion coefficient (D2 = 12.13 µm2·h-1). These results contributed to expanding the application of starch-based nanocomposites in future environmentally friendly food packaging.


Assuntos
Amilopectina/análogos & derivados , Amilose/análogos & derivados , Embalagem de Alimentos , Nanocompostos/química , Plastificantes/química , Triacetina/química , Difusão , Cinética , Zea mays/química
5.
Food Chem ; 336: 127660, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32771898

RESUMO

Curcumin is a powerful coloring agent widely used in the food industry. Its extraction from the plant Curcuma longa is commonly done with aqueous solvent solutions. In contrast to the conventional extraction methods, the present study aimed to compare two different green and bio-based surfactant-free microemulsion (SFME) extraction systems, which are approved for food and yield a higher extracting power of curcuminoids. Two SFMEs, water/ethanol/triacetin and water/diacetin/triacetin, were investigated via dynamic light scattering. Curcumin solubility in binary mixtures consisting of ethanol/triacetin or diacetin/triacetin was studied both experimentally and theoretically using UV-Vis measurements and COSMO-RS. The SFMEs were further examined and compared to a common ethanol/water (80/20) extraction mixture with respect to their extracting ability using high performance liquid chromatography. The SFMEs containing ethanol were found to extract ~18% more curcuminoids than the SFMEs containing diacetin and ~53% more than the ordinary ethanol/water mixture.


Assuntos
Curcuma/química , Curcumina/química , Curcumina/isolamento & purificação , Emulsões/química , Cromatografia Líquida de Alta Pressão/métodos , Curcumina/análise , Diarileptanoides/química , Difusão Dinâmica da Luz , Etanol/química , Química Verde , Extratos Vegetais/química , Solubilidade , Solventes/química , Espectrofotometria Ultravioleta , Tensoativos/química , Triacetina/química , Água/química
6.
J Chromatogr Sci ; 59(1): 23-29, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33078189

RESUMO

In our present study, the standard chemicals of triacetin were purified by reverse-phase and normal-phase semi-preparative high-performance liquid chromatography (HPLC), and 1H NMR and 13C NMR were employed to determine the purity and structure of triacetin. Moreover, a simple and rapid HPLC-photodiode array (PDA) method was developed to determine the contents of triacetin in 30 batches from different suppliers. The chromatographic separation was performed on a Phenomenex Gemini-NX C18 column (250 × 4.6 mm, 5 µm) using a gradient elution system of water and acetonitrile (contained 0.1% of formic acid) solution with a flow rate of 1.0 mL/min at 30°C at 210 nm. Sample preparation method is rapid and energy efficient, and the obtained sample have a good purity. Validation shows good specificity, linearity (R2 = 0.9995), precision, stability, repeatability (% RSD < 2.80) and the average recovery (99.72%) of triacetin. The content of triacetin in most samples is concentrated in 94-97%. This developed approach is simple, rapid, accurate and can be used to quickly determine the purity and the content of triacetin in plasticizers and filter plugs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Triacetina/análise , Triacetina/química , China , Cromatografia de Fase Reversa , Contaminação de Medicamentos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Molecules ; 25(22)2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182532

RESUMO

In this study, an optimized mesoporous sulfonated carbon (OMSC) catalyst derived from palm kernel shell biomass was developed using template carbonization and subsequent sulfonation under different temperatures and time conditions. The OMSC catalyst was characterized using acid-base titration, elemental analysis, XRD, Raman, FTIR, XPS, TPD-NH3, TGA-DTA, SEM, and N2 adsorption-desorption analysis to reveal its properties. Results proved that the OMSC catalyst is mesoporous and amorphous in structure with improved textural, acidic, and thermal properties. Both FTIR and XPS confirmed the presence of -SO3H, -OH, and -COOH functional groups on the surface of the catalyst. The OMSC catalyst was found to be efficient in catalyzing glycerol conversion to acetin via an acetylation reaction with acetic acid within a short period of 3 h. Response surface methodology (RSM), based on a two-level, three-factor, face-centered central composite design, was used to optimize the reaction conditions. The results showed that the optimized temperature, glycerol-to-acetic acid mole ratio, and catalyst load were 126 °C, 1:10.4, and 0.45 g, respectively. Under these optimum conditions, 97% glycerol conversion (GC) and selectivities of 4.9, 27.8, and 66.5% monoacetin (MA), diacetin (DA), and triacetin (TA), respectively, were achieved and found to be close to the predicted values. Statistical analysis showed that the regression model, as well as the model terms, were significant with the predicted R2 in reasonable agreement with the adjusted R2 (<0.2). The OMSC catalyst maintained excellent performance in GC for the five reaction cycles. The selectivity to TA, the most valuable product, was not stable until the fourth cycle, attributable to the leaching of the acid sites.


Assuntos
Bacteriocinas/química , Carbono/química , Glicerídeos/química , Enxofre/química , Triacetina/química , Catálise , Química Orgânica/métodos , Glicerol/química , Microscopia Eletrônica de Varredura , Modelos Estatísticos , Análise de Regressão , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Temperatura , Termogravimetria , Difração de Raios X
8.
Int J Mol Sci ; 21(18)2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32899537

RESUMO

To exploit the hydrolytic activity and high selectivity of immobilized lipase B from Candida antarctica on octyl agarose (CALB-OC) in the hydrolysis of triacetin and also to produce new value-added compounds from glycerol, this work describes a chemoenzymatic methodology for the synthesis of the new dimeric glycerol ester 3-((2,3-diacetoxypropanoyl)oxy)propane-1,2-diyl diacetate. According to this approach, triacetin was regioselectively hydrolyzed to 1,2-diacetin with CALB-OC. The diglyceride product was subsequently oxidized with pyridinium chlorochromate (PCC) and a dimeric ester was isolated as the only product. It was found that the medium acidity during the PCC treatment and a high 1,2-diacetin concentration favored the formation of the ester. The synthesized compounds were characterized using IR, MS, HR-MS, and NMR techniques. The obtained dimeric ester was evaluated at 100 ppm against seven bacterial strains and two Candida species to identify its antimicrobial activity. The compound has no inhibitory activity against the bacterial strains used but decreased C. albicans and C. parapsilosis growth by 49% and 68%, respectively. Hemolytic activity was evaluated, and the results obtained support the use of the dimeric ester to control C. albicans and C. parapsilosis growth in non-intravenous applications because the compound shows hemolytic activity.


Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Éteres de Glicerila/síntese química , Lipase/química , Lipase/metabolismo , Candida/química , Diglicerídeos/química , Enzimas Imobilizadas/química , Ésteres , Hidrólise , Oxidantes , Compostos de Piridínio/química , Triacetina/química
9.
J Chem Theory Comput ; 16(7): 4734-4743, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32496775

RESUMO

The characterization of the affinity and binding mechanism of specific molecules to a protein active site is scientifically and industrially relevant for many applications. In principle, this information can be obtained using molecular dynamics (MD) simulations by calculating the free energy profile of the process. However, this is a computationally demanding calculation. Currently, coarse-grained (CG) force fields are very well implemented for MD simulations of biomolecular systems. These computationally efficient force fields are a major advantage to the study of large model systems and/or those requiring long simulation times. The Martini model is currently one of the most popular CG force fields for these systems. For the specific case of protein simulations, to correctly maintain the macromolecular three-dimensional structure, the Martini model needs to include an elastic network (EN). In this work, the effect of protein flexibility, as induced by three EN models compatible with the Martini force field, was tested on the calculation of free energy profiles for protein-ligand binding. The EN models used were ElNeDyn, GoMartini, and GEN. The binding of triolein (TOG) and triacetin (TAG) to a lipase protein (thermomyces lanuginosa lipase-TLL) was used as a case study. The results show that inclusion of greater flexibility in the CG parameterization of proteins is of high importance in the calculation of the free energy profiles of protein-ligand systems. However, care must be taken in order to avoid unjustified large protein deformations. In addition, due to molecular flexibility there may be no absolute need for the center of the ligand to reach the center of the protein-binding site. The calculation of the energy profile to a distance of about 0.5 nm from the active site center can be sufficient to differentiate the affinity of different ligands to a protein.


Assuntos
Proteínas Fúngicas/química , Ligantes , Lipase/química , Sítios de Ligação , Eurotiales/enzimologia , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Triacetina/química , Triacetina/metabolismo , Trioleína/química , Trioleína/metabolismo
10.
Int J Pharm ; 573: 118873, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31765772

RESUMO

The potential for zero-order drug-release was evaluated for ethyl cellulose (EC) coated, acetaminophen-layered sugar pellets (Suglets®) of mesh size 18/20 (850-1000 µm). To determine optimal plasticizer/pore-former concentrations for EC films, solvent-cast Aquacoat® ECD (ethyl cellulose dispersion) films were prepared with 0-50% w/w ratios of two triethyl citrate (TEC) or triacetin (TA). Characterization studies showed that films with excipient concentrations ≥20% were homogenous, mechanically strong at room temperature (Young's modulus of 25-35 MPa), and have a glass transition (Tg) in the range of 20-45 °C. Based on these results, a working range of 20-50% weight concentrations was selected for drug release studies. Suglets® were layered with acetaminophen (APAP) using Wurster Glatt GPCG-3 to yield roughly 10% w/w coating (controls). The Controls were coated using the same Wurster process with Aquacoat® ECD containing 20-50% w/w of TEC or TA. Samples were removed periodically at 3-11% weight gain, to evaluate impact of weight gain, and consequently film-formation, on drug release. Dissolution was monitored over a period of 12 h in a media consisting of simulated gastric fluid (first two hours), followed by simulated intestinal fluid. The controls showed near 100% release within the first 30 min, indicating the value of EC-coating to achieve controlled release. Dissolution release profiles showed that TEC is more effective than TA as a plasticizer and pore-former, as linear profiles were apparent at lower concentrations and % weight gain. For a quantitative evaluation of these results, linear regression was fitted to all cumulative release profiles, and R-squared values examined as a function of excipient concentration and % weight gain. The corresponding response surface plots and the second order regression were shown to aid in optimization. The design space for zero-order release was represented as contour plots between excipient concentration and % weight gain.


Assuntos
Acetaminofen/farmacocinética , Celulose/análogos & derivados , Excipientes/química , Plastificantes/química , Acetaminofen/administração & dosagem , Acetaminofen/química , Administração Oral , Celulose/química , Química Farmacêutica , Citratos/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Composição de Medicamentos/instrumentação , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Transição de Fase , Solubilidade , Triacetina/química
11.
Carbohydr Polym ; 222: 114973, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320052

RESUMO

The viscoelastic behaviour of cellulose acetate with a degree of substitution (DS) of 245 plasticized by triacetin was studied at short times by dynamic oscillatory measurements. Two distinct regimes and unexpected scaling behaviour according to plasticizer content were highlighted. The dynamics of chains and their structural organization are not modified up to 35 wt% of triacetin. The rheological behaviour is led by a constant correlation length corresponding to the distance between strong intermolecular interactions subsisting in the melt state at high temperature even in the presence of plasticizer. This particular structure involves the apparition of strain hardening effects during uniaxial extensional flow tests and an important elasticity corresponding to the apparition of a Weissenberg effect at really low shear rates during shear sweeps. Intramolecular hydrogen bonds are responsible of the high rigidity of cellulose acetate chains. Plasticized cellulose acetate in the melt state belongs to the class of associating polymers and its rheological behaviour is mainly led by stickers.


Assuntos
Celulose/análogos & derivados , Plastificantes/química , Triacetina/química , Celulose/química , Elasticidade , Ligação de Hidrogênio , Reologia , Temperatura , Viscosidade
12.
Int J Pharm ; 565: 20-32, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31051232

RESUMO

The target of the current study is to formulate letrozole loaded nanoemulsion (LET-NE) for the direct nose to brain delivery to reduce peripheral effects of letrozole (LET). LET-NE is compared against intraperitoneally administered free LET in kainic acid (KA) induced status epilepticus (SE) in mice. LET loaded nanoemulsion (LET-NE) was prepared by aqueous microtitration method using Triacetin, Tween 80 and PEG-400 as the oil phase, surfactant, and co-surfactant. Nanoemulsion was studied for droplet size, polydispersity index (PDI), zeta potential, percentage transmittance, drug content, surface morphology. TEM images of developed formulation demonstrated spherical droplets with a mean diameter of 95.59 ±â€¯2.34 nm, PDI of 0.162 ±â€¯0.012 and zeta potential of -7.12 ±â€¯0.12 mV respectively. In in-vitro and ex-vivo drug release, LET-NE showed prolonged drug release profile as compared to suspension. SE was induced by KA (10 mg/kg, i.p.) in Swiss albino mice. Behavioral seizure monitoring, biochemical estimations, and histopathological examination were performed. The onset time of SE was significantly enhanced and % incidence of SE was reduced by intranasal administration of LET-NE as compared to KA and LET administered intraperitoneally. Biochemical estimations revealed that LET-NE effectively decreased levels of 17-ß estradiol while the levels of 5α-Dihydrotestosterone (5α-DHT) and 3α-androstanediol (3α-Diol) were significantly increased in the hippocampus. In cresyl violet staining LET-NE showed better protection of the hippocampus from neurotoxicity induced by KA as compared to LET. Also, in gamma scintigraphy of mouse brain, intranasal administration of nanoemulsion exhibited the presence of high concentration of LET. The study demonstrates the anticonvulsant and neuroprotective effect of LET-NE probably by inhibition of aromatization of testosterone into 17-ß estradiol, proconvulsant, and diverting the pathway into the synthesis of testosterone metabolites, 3α-Diol with known anticonvulsant and neuroprotective action. Brain targeting of LET-NE showed better anticonvulsant and neuroprotective action than LET.


Assuntos
Anticonvulsivantes/administração & dosagem , Inibidores da Aromatase/administração & dosagem , Sistemas de Liberação de Medicamentos , Letrozol/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Estado Epiléptico/tratamento farmacológico , Animais , Anticonvulsivantes/química , Inibidores da Aromatase/química , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Di-Hidrotestosterona/sangue , Desenho de Fármacos , Liberação Controlada de Fármacos , Emulsões , Estradiol/sangue , Cabras , Ácido Caínico , Letrozol/química , Masculino , Camundongos , Mucosa Nasal/metabolismo , Fármacos Neuroprotetores/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polissorbatos/administração & dosagem , Polissorbatos/química , Estado Epiléptico/induzido quimicamente , Triacetina/administração & dosagem , Triacetina/química
13.
Int J Pharm ; 565: 367-377, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31071420

RESUMO

This study assesses the feasibility of printing implantable devices using 3D printing Fused deposition modeling (FDM) technology. The influence of the deposition temperature, the deposition rate and the layer thickness on the printing process and the physical properties of the devices were evaluated. The filaments were composed of neat poly(lactic acid) (PLA) and blends of different plasticizers (polyethylene glycol 400 (PEG 400), triacetine (TA), acetyltriethyl citrate (ATEC) and triethyl citrate (TEC)) at 10% (w/w). The assessment of thermomechanical characteristics and morphology of both filaments and devices (cylinders and dog bones) were performed. The influence of each parameter was evaluated using a design of experiment (DoE) and the significance of the results was discussed. A large amount of data about the evaluation of FDM process parameters are already available in the literature. However, specific insights needed to be increased into the impact of the use of PLA and plasticized PLA raw material on the feasibility of printing devices in three dimensions. To conclude, the ductility was improved with a high layer thickness, low temperature and using ATEC. Whereas, adhesion was promoted with an increase in temperature, a lower layer thickness and adding TA.


Assuntos
Poliésteres/química , Impressão Tridimensional , Tecnologia Farmacêutica , Citratos/química , Plastificantes/química , Polietilenoglicóis/química , Temperatura , Triacetina/química
14.
Environ Sci Pollut Res Int ; 25(22): 22035-22051, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29797204

RESUMO

The energy situation and the concerns about global warming nowadays have ignited research interest in non-conventional and alternative fuel resources to decrease the emission and the continuous dependency on fossil fuels, particularly for various sectors like power generation, transportation, and agriculture. In the present work, the research is focused on evaluating the performance, emission characteristics, and combustion of biodiesel such as palm kernel methyl ester with the addition of diesel additive "triacetin" in it. A timed manifold injection (TMI) system was taken up to examine the influence of durations of several blends induced on the emission and performance characteristics as compared to normal diesel operation. This experimental study shows better performance and releases less emission as compared with mineral diesel and in turn, indicates that high performance and low emission is promising in PKME-triacetin fuel operation. This analysis also attempts to describe the application of the fuzzy logic-based Taguchi analysis to optimize the emission and performance parameters.


Assuntos
Biocombustíveis , Óleo de Palmeira/química , Emissões de Veículos/análise , Ésteres/química , Modelos Teóricos , Triacetina/química
15.
J Pharm Biomed Anal ; 150: 95-106, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29216591

RESUMO

For poly (lactide-co-glycolide acid) (PLGA)-based in situ forming implants, the rate of implant formation plays an important role in determining the overall drug release kinetics. Currently, in vitro techniques capable of characterizing the processes of drug release and implant formation at the same time are not available. A hydrogel-based in vitro experimental setup was recently developed requiring only microliter of formulation and forming a closed system potentially suitable for interfacing with various spectroscopic techniques. The aim of the present proof-of-concept study was to investigate the feasibility of concomitant UV imaging, Vis imaging and light microscopy for detailed characterization of the behavior of in situ forming PLGA implants in the hydrogel matrix mimicking the subcutis. The model compounds, piroxicam and α-lactalbumin were added to PLGA-1-methyl-2-pyrrolidinone and PLGA-triacetin solutions. Upon bringing the PLGA-solvent-compound pre-formulation in contact with the hydrogel, Vis imaging and light microscopy were applied to visualize the depot formation and UV imaging was used to quantify drug transport in the hydrogel. As compared to piroxicam, the α-lactalbumin invoked an acceleration of phase separation and an increase of implant size. α-Lactalbumin was released faster from the PLGA-1-methyl-2-pyrrolidinone system than the PLGA-triacetin system opposite to the piroxicam release pattern. A linear relationship between the rate of implant formation and initial compound release within the first 4h was established for the PLGA-NMP systems. This implies that phase separation may be one of the controlling factors in drug release. The rate of implant formation may be an important parameter for predicting and tailoring drug release. The approach combining UV imaging, Vis imaging and light microscopy may facilitate understanding of release processes and holds potential for becoming a useful tool in formulation development of in situ forming implants.


Assuntos
Sistemas de Liberação de Medicamentos , Lactalbumina/administração & dosagem , Ácido Láctico/química , Piroxicam/administração & dosagem , Ácido Poliglicólico/química , Química Farmacêutica/métodos , Portadores de Fármacos/química , Implantes de Medicamento , Liberação Controlada de Fármacos , Hidrogéis , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pirrolidinonas/química , Espectrofotometria Ultravioleta/métodos , Análise Espectral/métodos , Tela Subcutânea/metabolismo , Triacetina/química
16.
Pak J Pharm Sci ; 30(2(Suppl.)): 601-606, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28650328

RESUMO

The aim of the study was to successfully design, formulate and evaluate self-nanoemulsifying drug delivery system (SNEDDS) of poorly aqueous soluble drug viz. flurbiprofen using long (LCT), medium (MCT) and short chain triglycerides (SCT). The SNEDDS are thermodynamically stable lipid based drug delivery systems which consist of mixture of oil, surfactant and co-surfactant. Upon aqueous dilution, this mixture produces nano-emulsion spontaneously on slight agitation. The excipients intended to be used were screened for their potential to dissolve the drug and to form clear dispersion upon aqueous dilution. Labrafil M 1944 CS, capryol-90 and triacetin were selected as long, medium and short chain triglycerides, respectively, as lipids while tween-80 and polyethylene glycol-400 (PEG-400)/ethanol (3:1 ratio) were selected as surfactant and co-surfactant, respectively. The excipients were studied at every possible combination ratios using pseudo-ternary diagram. The LCT, MCT and SCT-SNEDDS were optimized using thermodynamic studies, percentage transmittance value, viscosity, refractive index (RI), electrical conductivity, globule size analysis and in-vitro drug release studies. The drug release profiles of optimized SNEDDS were then compared with market product at different pH mediums. The LCT-SNEDDS was considered to be superior for enhancement of the drug bioavailability when compared with other SNEDDS formulations and market product.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Flurbiprofeno/administração & dosagem , Flurbiprofeno/farmacocinética , Nanopartículas/química , Triglicerídeos/química , Administração Oral , Disponibilidade Biológica , Liberação Controlada de Fármacos , Emulsões/administração & dosagem , Glicerídeos/química , Nanopartículas/administração & dosagem , Tamanho da Partícula , Polietilenoglicóis/química , Polímeros/química , Polissorbatos/química , Propilenoglicóis/química , Triacetina/química , Triglicerídeos/administração & dosagem
17.
Colloids Surf B Biointerfaces ; 154: 350-356, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28365424

RESUMO

Oil-in-water (O/W) microemulsions based on Tween 80 as the emulsifier and triacetin as the dispersed oil phase were formulated to be used as delivery vehicles of Vemurafenib analog PLX4720. PLX4720 is a lipophilic antitumor drug against various cancer types correlated with the BRAFV600E mutation. The limits of the single-phase region corresponding to O/W microemulsions as described by ternary phase diagrams were examined. Droplet size measurements determined by dynamic light scattering (DLS) showed mean droplet diameters equal to 10±0.1nm both in the presence and in absence of the drug. Cryogenic-transmission electron microscopy (Cryo-TEM) images of the microemulsions showed the existence of small structures with uniform size distribution having also average diameters of approximately 10nm. Electron paramagnetic resonance (EPR) spectroscopy applying the spin probing technique confirmed PLX4720 location in the oil cores excluding its participation in the surfactants monolayer. Furthermore, cell viability assays on colon cancer cell lines Colo-205 and HT29 showed that microemulsions did not exhibit any cytotoxicity when added in ratios between 0.005% v/v and 0.2% v/v. When the cells were treated with encapsulated PLX4720 at two different concentrations (0.063 and 0.12µΜ) the same response as when dissolved in classic DMSO was observed.


Assuntos
Antineoplásicos/química , Portadores de Fármacos , Indóis/química , Nanocápsulas/química , Polissorbatos/química , Sulfonamidas/química , Triacetina/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Emulsões , Células HT29 , Humanos , Indóis/farmacologia , Nanocápsulas/ultraestrutura , Sulfonamidas/farmacologia , Tensoativos/química
18.
Artif Cells Nanomed Biotechnol ; 45(3): 591-597, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28211300

RESUMO

The aim of this study was to investigate the wound healing effects of clove oil (CO) via its encapsulation into nanoemulsion. Optimized nanoemulsion (droplet size of 29.10 nm) was selected for wound healing investigation, collagen determination, and histopathological examination in rats. Optimized nanoemulsion presented significant would healing effects in rats as compared to pure CO. Nanoemulsion also presented significant enhancement in leucine content (0.61 mg/g) as compared to pure CO (0.50 mg/g) and negative control (0.31 mg/g). Histopathology of nanoemulsion treated rats showed no signs of inflammatory cells. These results suggested that nanoemulsion of CO was safe and nontoxic.


Assuntos
Antibacterianos/farmacologia , Óleo de Cravo/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Óleo de Cravo/química , Colágeno/agonistas , Colágeno/biossíntese , Emulsões , Feminino , Glicerídeos/química , Nanoestruturas , Tamanho da Partícula , Polissorbatos/química , Ratos , Ratos Wistar , Pele/lesões , Triacetina/química , Cicatrização/fisiologia
19.
Molecules ; 22(12)2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29292721

RESUMO

Lipases with unique characteristics are of value in industrial applications, especially those targeting cost-effectiveness and less downstream processes. The aims of this research were to: (i) optimize the fermentation parameters via solid state fermentation (SSF); and (ii) study the performance in hydrolysis and esterification processes of the one-step partially purified Schizophyllum commune UTARA1 lipases. Lipase was produced by cultivating S. commune UTARA1 on sugarcane bagasse (SB) with used cooking oil (UCO) via SSF and its production was optimized using Design-Expert® 7.0.0. Fractions 30% (ScLipA) and 70% (ScLipB) which contained high lipase activity were obtained by stepwise (NH4)2SO4 precipitation. Crude fish oil, coconut oil and butter were used to investigate the lipase hydrolysis capabilities by a free glycerol assay. Results showed that ScLipA has affinities for long, medium and short chain triglycerides, as all the oils investigated were degraded, whereas ScLipB has affinities for long chain triglycerides as it only degrades crude fish oil. During esterification, ScLipA was able to synthesize trilaurin and triacetin. Conversely, ScLipB was specific towards the formation of 2-mono-olein and triacetin. From the results obtained, it was determined that ScLipA and ScLipB are sn-2 regioselective lipases. Hence, the one-step partial purification strategy proved to be feasible for partial purification of S. commune UTARA1 lipases that has potential use in industrial applications.


Assuntos
Fermentação , Lipase/química , Schizophyllum/enzimologia , Esterificação , Óleos de Peixe/química , Glicerol/química , Hidrólise , Cinética , Lipase/isolamento & purificação , Lipase/metabolismo , Ácidos Oleicos/química , Óleos de Plantas/química , Triacetina/química , Triglicerídeos/química
20.
Eur J Pharm Sci ; 92: 146-55, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27402100

RESUMO

Recent studies have demonstrated polymer films to be a promising platform for delivery of poorly water-soluble drug particles. However, the impact of critical material attributes, for example plasticizer, on the properties of and drug release from such films has yet to be investigated. In response, this study focuses on the impact of plasticizer and plasticizer concentration on properties and dissolution rate of polymer films loaded with poorly water-soluble drug nanoparticles. Glycerin, triacetin, and polyethylene glycol were selected as film plasticizers. Griseofulvin was used as a model Biopharmaceutics Classification System class II drug and hydroxypropyl methylcellulose was used as a film-forming polymer. Griseofulvin nanoparticles were prepared via wet stirred media milling in aqueous suspension. A depression in film glass transition temperature was observed with increasing plasticizer concentration, along with a decrease in film tensile strength and an increase in film elongation, as is typical of plasticizers. However, the type and amount of plasticizer necessary to produce strong yet flexible films had no significant impact on the dissolution rate of the films, suggesting that film mechanical properties can be effectively manipulated with minimal impact on drug release. Griseofulvin nanoparticles were successfully recovered upon redispersion in water regardless of plasticizer or content, even after up to 6months' storage at 40°C and 75% relative humidity, which contributed to similar consistency in dissolution rate after 6months' storage for all films. Good content uniformity (<4% R.S.D. for very small film sample size) was also maintained across all film formulations.


Assuntos
Sistemas de Liberação de Medicamentos , Griseofulvina/química , Nanopartículas/química , Plastificantes/química , Glicerol/química , Derivados da Hipromelose/química , Polietilenoglicóis/química , Solubilidade , Suspensões , Triacetina/química , Água/química
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