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1.
Int J Biol Macromol ; 124: 1033-1039, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30496856

RESUMO

The present study investigates on the succinylation of native starch isolated from the rhizomes of Kaempferia galanga. Succinylated starch with different degree of substitution in the range of 0.030-0.189 was prepared using varying concentrations of succinic anhydride. Morphological study showed the formation of porous structure on the outer surface of the starch granules, whereas FTIR spectra showed the presence of ester group on the modified starches. With the increase in degree of substitution, there was an increased amylose content and less fraction of amylopectin and thereby modified starch samples showed relatively less water retention capacity and faster disintegration. The swelling and solubility power of native and modified starches were found to increase with increase in temperature. From the TGA analysis, the succinylated starches were found to be more thermally stable than native starch. In vitro drug release study also supports the disintegration pattern and proves the potential of succinylated Kaempferia galanga starch as resilient material in sustained-drug release systems.


Assuntos
Amilopectina/química , Amilose/química , Rizoma/química , Ácido Succínico/química , Zingiberaceae/química , Preparações de Ação Retardada/química
2.
Int J Biol Macromol ; 122: 417-424, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30336248

RESUMO

Starch mixture is an important approach in designing drug delivery system with modulated properties. The aim of the present work is to study the effect of pregelatinization on starch mixture by varying the concentration of palmyrah and maize starch. All the starch mixtures were statistically designed using 32 full factorial design. Further, the mixtures were characterized for physicochemical and drug release properties. The amylose content, water holding capacity (WHC), swelling and solubility power tend to increase with increase in pregelatinization time. The X-ray diffractogram (XRD) confirmed the reduction in crystallinity of starch mixture with increase in pregelatinization time. The FT-IR study confirmed the gelatinization characteristics of the mixture. All the pregelatinized starch mixture exhibited shear-thinning behavior. Micromeritic property of various starch mixture showed the good flow properties. Formulation with this novel excipient system, using paracetamol as model drug indicated its utility for immediate release dosage form.


Assuntos
Arecaceae/química , Amido/química , Zea mays/química , Amilose/análise , Solubilidade , Viscosidade , Água/química
3.
Int J Biol Macromol ; 118(Pt B): 2156-2162, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30009917

RESUMO

Polysaccharides with unique functional and drug release characteristics have received more and more attention in the field of drug delivery systems. In this study, characterization of polysaccharide (PPSP) from yellow poinciana seeds and its utility as pharmaceutical excipient was investigated. The molecular weight of isolated PPSP was found to be 1.33 × 102 kDa. The high swelling and water binding capacity, low moisture content and fat-binding capacity of isolated polysaccharide explore to use as an excipient for drug delivery. The micromeritic properties revealed its flow and compressibility properties rendering its use in tablet manufacturing. Zeta potential measurements revealed PPSP as non-ionic polysaccharide. TGA data reveals a thermally stable polysaccharide and SEM confirms the fibrous network-like structure. The monosaccharide analysis confirmed the presence of galactose (49.94%), glucose (22.69%), mannose (15.99%), rhamnose (2.36%), arabinose (5.74%) and fucose (3.30%). The XRD pattern and viscosity measurements confirm the semi-crystalline nature and shear thinning behavior of polysaccharide respectively. The drug release profile indicates that the polysaccharide can be used as a potential agent for the design of smart pH-sensitive drug delivery systems.


Assuntos
Liberação Controlada de Fármacos , Fabaceae/química , Polissacarídeos/química , Cinética , Monossacarídeos/análise , Polissacarídeos/ultraestrutura , Solubilidade , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Viscosidade , Difração de Raios X
4.
Int J Biol Macromol ; 116: 239-246, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29719218

RESUMO

Smart polymers, one of the class of polymers with extensive growth in the last few decades due to their wide applications in drug targeting and controlled delivery systems. With this in mind, the aim of the present study is to design and formulate smart releasing o/w emulsion by using Albizia lebbeck L. seed polysaccharide (ALPS). For this purpose, the physicochemical and drug release characteristics like emulsion capacity (EC), emulsion stability (ES), viscosity, microscopy, zeta potential, polydispersity index (PDI) and in-vitro drug release were performed. The EC and ES values were found to increase with an increased concentration of ALPS. The emulsion formulations were statistically designed by using 32 full factorial design. All the emulsions showed a shear-thinning behavior. The zeta potential and polydispersity index were found to be in the range of -35.83 mV to -19.00 mV and 0.232-1.000 respectively. Further, the percent cumulative drug release of the emulsions at 8 h was found to be in the range of 30.19-82.65%. The drug release profile exhibited zero order release kinetics. In conclusion, the ALPS can be used as a natural emulsifier and smart polymer for the preparation of pH sensitive emulsions in drug delivery systems.


Assuntos
Albizzia/química , Emulsificantes/química , Emulsões/química , Polissacarídeos/química , Sementes/química , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Estabilidade de Medicamentos , Excipientes/química , Tamanho da Partícula , Polímeros/química , Reologia/métodos , Viscosidade/efeitos dos fármacos
5.
Carbohydr Polym ; 175: 502-508, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917894

RESUMO

Plant polysaccharides, generally regarded as safe (GRAS), are gaining importance as excipients in drug delivery. Therefore, the current paper presents the studies on structural, functional and drug release study of water soluble polysaccharide (ALPS) from seeds of Albizia lebbeck L. High swelling, water holding capacity, foam stability and lower moisture content suggests its use as additive in food preparations. The apparent molecular weight of polysaccharide was found to be 1.98×102kDa. Monosaccharide composition analysis indicated that ALPS consists of mannose (4.06%), rhamnose (22.79%), glucose (38.9%), galactose (17.84%) and xylose (16.42%). Micromeritic properties revealed that the polysaccharide possess potential for pharmaceutical applications. From the surface charge analysis, ALPS was found to be non-ionic polysaccharide. Morphological study reveals the polysaccharide with irregular particle shape and rough surface. Fourier transformed infrared spectroscopy (FTIR) study confirms the carbohydrate nature of polysaccharide. From the thermogravimetric analysis (TGA) data, the second mass loss (243-340°C) attributed to polysaccharide degradation. The drug release profile reveals the use of polysaccharide for the preparation of pH sensitive pharmaceutical dosage forms.


Assuntos
Albizzia/química , Portadores de Fármacos/química , Polissacarídeos/química , Sementes/química , Liberação Controlada de Fármacos , Excipientes/química , Concentração de Íons de Hidrogênio , Monossacarídeos , Espectroscopia de Infravermelho com Transformada de Fourier , Água
6.
Int J Biol Macromol ; 74: 523-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25561049

RESUMO

Increasing demand and considerable attention to the non-conventional sources of starches leads to explore new sources. Starches of Dioscorea (Da1 and Da2) from Jharkhand, North Eastern region of India have been studied for its physicochemical properties. An attempt has been made to study the carboxymethylated derivatives of starches from two varieties of Dioscorea of this region. Different concentration of monochloroacetate was used to study the effect of degree of substitution (DS) on the physicochemical properties of starches. A considerable effect of DS was noticed on the ash content, amylose content, water-holding capacity, swelling and solubility power of carboxymethylated derivatives. Morphological studies showed the increase in the deformation of structure of the starch granule with an increase in the degree of substitution. FTIR confirmed the carboxymethylation reaction. TGA data of carboxymethylated starches revealed the stability to the temperature. Micromeritics of starch powder and granules showed the value which makes these starches to be utilized as an excipient. With the increase in DS, the % release of drug was found to be decreased. This further makes the carboxymethyl derivatives of Dioscorea a good source to be used as an excipient for sustained release formulations.


Assuntos
Dioscorea/química , Amido/análogos & derivados , Amilose , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Amido/ultraestrutura , Comprimidos/química , Termogravimetria
7.
Int J Biol Macromol ; 72: 1020-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25451752

RESUMO

Starch from Kyllinga nemoralis (KNSS) rhizomes was investigated for its morphological, chemical and functional properties in order to utilize its potential as a pharmaceutical adjuvant. Rhizomes of K. nemoralis yielded an appreciable amount of starch that is 19.77% (w/w). Amylose content was measured as of 28.66%. The shapes of starch granules were mostly round, disc like, flat and the size varied from 3.93 to 9.45 µm. Further polysaccharide nature of KNSS was confirmed by FTIR spectra. The solubility and swelling power was found to be increased with the increase in the temperature. Micromeritic properties of the isolated starch showed unique feasibility of KNSS being used as a pharmaceutical excipient. The TGA data revealed that KNSS is thermally stable with less bound water. In vitro release study confirmed that KNSS in pH 6.8 slows down the release of the drug smartly compared to pH 1.2, due its ability to respond to the external pH-stimuli. Release profile proved that KNSS could find an application as a smart polymer for its stimuli-responsive and bio-related applications such as drug delivery.


Assuntos
Amilose/química , Rizoma/química , Amido/química , Cyperaceae/química , Sistemas de Liberação de Medicamentos , Humanos , Polímeros/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
8.
J Nat Med ; 68(2): 284-94, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23934054

RESUMO

Amukkara choornam ethanolic extract (ACE) was investigated for phytochemical screening, content of total phenolics and flavonoids, in vitro radical scavenging activity (RSA), quantification of various antiulcer marker compounds (i.e., eugenol, piperine, trans-caryophyllene, and withaferine A) by a validated HPTLC method, and evaluated for its in vivo gastroprotective ability against ethanol (EtOH)-induced and pylorus ligation (PL)-induced ulcer models in rats. Phytochemical screening revealed the presence of flavonoids, saponins, phenols, bitter principles, and steroids. Total phenolic and flavonoid content was found to be 61.12 ± 0.72 mg GAE/g of ACE and 24.06 ± 1.07 mg RE/g of ACE, respectively; this was found to be very high in plant extracts showing very good antioxidant and antiulcerogenic effect. RSA of ACE appeared significantly (p < 0.05) lower than that of ascorbic acid (AA), but higher than that of ranitidine (RAN). In vivo the pretreatment of rats with RAN (100 mg/kg) and 50, 100, and 200 mg/kg doses of ACE significantly reduced the ulcer index in a dose-dependant manner in both the models by blocking lipid peroxidation and by significant increases in superoxide dismutase and catalase activity. But rats treated with AA (200 mg/kg) did not have any effect on the ulcer induced by EtOH or PL as it has very good in vitro and in vivo antioxidant activity. HPTLC analysis showed the presence of 0.198 ± 0.01 µg/g, 0.754 ± 0.06 mg/g, 3.50 ± 0.04, and 0.854 ± 0.04 µg/g of eugenol, piperine, trans-caryophyllene, and withaferine A per gram of Amukkara choornam (AC). So the antiulcerogenic activity of ACE might be due to a possible synergistic antioxidant, supported by the holistic approach of polyherbal formulations, i.e., systematism, multi-target and multi-channel owing to their complex chemical constituents and antihistaminic-like effects.


Assuntos
Antiulcerosos/uso terapêutico , Antagonistas dos Receptores Histamínicos/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , Antiulcerosos/química , Antiulcerosos/normas , Antioxidantes/uso terapêutico , Flavonoides/análise , Antagonistas dos Receptores Histamínicos/química , Antagonistas dos Receptores Histamínicos/normas , Peroxidação de Lipídeos/efeitos dos fármacos , Fenóis/análise , Extratos Vegetais/química , Extratos Vegetais/normas , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
9.
Int J Biol Macromol ; 61: 396-403, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23921208

RESUMO

Starch isolated from under-utilized seeds of five different cultivars of Lagenaria siceraria (Mol.) standley (Cucurbitaceae) was carboxymethylated. The influence of the degree of substitution (DS) on physicochemical properties and drug release properties of starches was studied. The physicochemical profiles of the derivatives were assessed by means of FT-IR, XRD, SEM, elemental analysis, reaction efficiency, water binding capacity, swelling power, powder characteristics and visual estimation. The highest values of the DS obtained when the carboxymethylation was performed at 45 °C for 4h. Scanning electron microscopy (SEM) showed that after carboxymethylation, the granular appearance of the native starch was distorted. The new bands at 1576.87 cm(-1) and 1423.81 cm(-1) in Fourier transform infrared (FT-IR) indicated that the starch granules were substituted. Wide-angle X-ray diffractometry revealed that crystallinity was reduced significantly after carboxymethylation. Powder studies revealed that these starches possess potential for pharmaceutical applications. The matrix tablets were found to release the drug by Korsmeyer and Peppas kinetics. The carboxymethylated starches with high DS can be used as a drug release retardant in sustained release formulations, as the drug dissolution rate of native starches was significantly lower than the modified starches.


Assuntos
Cucurbitaceae/química , Amido/química , Portadores de Fármacos/química , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/isolamento & purificação , Amido/ultraestrutura , Comprimidos/química , Difração de Raios X
10.
Carbohydr Polym ; 96(1): 253-8, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23688478

RESUMO

There is an increasing interest in starch manufactured from edible tubers for controlled delivery of drug. Starches of different cultivars of Colocasia from Jharkhand, North Eastern State of India, were isolated and their morphological, physicochemical, structural properties were studied. The yield of starches was estimated in the range of 6.46-13.75%. All the isolated starches revealed their irregular shape with a diameter of 5-10 µm. There was considerable variation in amylose content, swelling and solubility power, water hydration capacity. FTIR spectra confirmed their carbohydrate nature. Powder studies revealed that these starches possess potential for pharmaceutical industries. In vitro release data revealed the delayed release of all tablets made by using Colocasia starches at pH 6.8 and 7.4 when compared with maize starch. Delayed release of all starches showed there is a great potential to be used these starches as pharmaceutical excipient in sustained release dosage form with minimum modification.


Assuntos
Colocasia , Preparações de Ação Retardada/química , Excipientes/química , Tubérculos/química , Amido/química , Amilose/análise , Preparações de Ação Retardada/isolamento & purificação , Excipientes/isolamento & purificação , Concentração de Íons de Hidrogênio , Índia , Pós , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/isolamento & purificação , Comprimidos , Água/análise
11.
Drug Dev Ind Pharm ; 39(8): 1175-86, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22607046

RESUMO

The objective of this study is to develop, in vitro and in vivo evaluation of novel approaches for controlled release of paroxetine hydrochloride hemihydrate (PHH) in comparison to patented formulation PAXIL CR(®) tablets of GlaxoSmithKline (Geomatrix™ technology). In one of the approaches, hydrophilic core matrix tablets containing 85% of the dose were prepared and further coated with methacrylic acid copolymer to delay the release. An immediate release coating of 15% was given as top coat. The tablets were further optionally coated using ethyl cellulose. In the second approach, hydrophobic matrix core tablets containing metharylic acid copolymer were prepared. In the third approach, PHH was granulated with enteric polymer and further hydrophobic matrix core tablets were prepared. The effect of polymer concentration, level of enteric coating on drug release was evaluated by in vitro dissolution study by varying dissolution apparatus and the rotation speeds. It was found that increase in concentration of high viscosity hydroxypropylmethylcellulose (HPMC) resulted in reduction of the release rate. The drug release was observed to be dependent on the level of enteric coating and ethyl cellulose coating, being slower at increased coating. The release mechanism of PHH followed zero-order shifting to dissolution dependent by the increase of HPMC content. The formulation was stable without change in drug release rate. In vivo study in human volunteers confirmed the similarity between test and innovator formulations. In conclusion, HPMC-based matrix tablets, which were further coated using methacrylic acid copolymer, were found to be suitable for the formulation of single layer-controlled release PHH.


Assuntos
Paroxetina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Adolescente , Adulto , Disponibilidade Biológica , Química Farmacêutica , Preparações de Ação Retardada , Humanos , Derivados da Hipromelose , Masculino , Metilcelulose/administração & dosagem , Metilcelulose/análogos & derivados , Pessoa de Meia-Idade , Paroxetina/química , Paroxetina/farmacocinética , Solubilidade , Comprimidos , Comprimidos com Revestimento Entérico
12.
Int J Biol Macromol ; 55: 193-200, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23201777

RESUMO

Starches were isolated from varieties of Dioscorea (Da1, Da2) grown in Jharkhand state of India and it was characterized in terms of moisture, ash, amylose content, bulk density, tapped density, true density, porosity, Carr's index, Hausner's ratio, swelling power, solubility, water holding capacity, paste clarity. Morphological, thermal and IR spectroscopic studies were also done to characterize the isolated starch. The shape and size of starch granules were round/oval to ellipsoid and 5-10µm. There were considerable differences in powder characteristics, amylose content, ash values, and water holding capacity, swelling and solubility power. Starch from variety Da2 showed high enthalpy of gelatinization temperature as compared to variety Da1. Peaks in FTIR spectra of both starches revealed its carbohydrate nature. In vitro studies revealed that both the starches from Da1 and Da2 can be used in developing sustained release formulations. The result showed that starches from both Dioscorea can be used in pharmaceutical industries as excipients with minimal modifications.


Assuntos
Dioscorea/química , Amido/química , Amilose/química , Concentração de Íons de Hidrogênio , Minerais/química , Pós/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/isolamento & purificação , Amido/ultraestrutura , Termodinâmica , Água
13.
Int J Biol Macromol ; 49(3): 305-10, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21600918

RESUMO

The objective of the study is to compare the different formulations prepared by using gum, grafted gum and hydrogel of katira as a carrier for colon-specific drug delivery using in vitro methods with and without enzymes. Katira gum is naturally occurring polysaccharides containing mainly l-rhamnose and d-galactose sugar unit and small percent of d-galactouronic acid. Compared to grafted gum and hydrogel, all proportions of katira gum protect the drug from being released completely in the physiological environment of the stomach and small intestine. In vitro release studies in enzymes (Pectinex Ultra SP-L having galactouronidase activity) have demonstrated the susceptibility of katira gum to the colonic bacterial enzyme (galactouronidase activity from Pectinex Ultra SP-L) with a consequent drug release. It illustrates that katira gum, a natural polysaccharide may be suitable as a carrier for colon targeting.


Assuntos
Química Farmacêutica/métodos , Colo/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Cinética , Especificidade de Órgãos
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