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1.
Food Chem ; 352: 129267, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33691207

RESUMO

In this study, a soluble complex formed between 0.5% (w/v) heated whey protein isolate (HWPI) and 5% (w/v) octenyl succinic anhydride (OSA)-modified starch at pH 4.5 was used to encapsulate ß-carotene for improving its solubility and stability. The apparent aqueous solubility of ß-carotene was increased markedly (264.05 ± 72.53 µg/mL) after encapsulation in the soluble complex. Transmission electron microscopy and scanning electron microscopy were used to evaluate the effect of the encapsulation of ß-carotene on the structure of the soluble complex. Fourier transform infrared spectroscopy showed that the characteristic peaks of ß-carotene disappeared in the soluble complex, suggesting that ß-carotene may have been encapsulated into the soluble complex via hydrophobic interactions. X-ray diffraction indicated that the ß-carotene was in an amorphous form within the soluble complex. An accelerated stability test showed that the soluble complex could effectively improve the chemical stability of ß-carotene during long-term storage under low pH conditions.


Assuntos
Amido/análogos & derivados , Proteínas do Soro do Leite/química , beta Caroteno/química , Cápsulas , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Amido/química
2.
Carbohydr Polym ; 254: 117294, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357863

RESUMO

The physicochemical properties and structural changes of potato starch esterified with octenyl succinic anhydride (OSA) assisted with pulsed electric field (PEF) were investigated. Results showed that PEF treatment during esterification resulted in a significant modification of pasting properties. The pasting temperature at 2-6 kV/cm reduced by 7.6-15.1 °C for PEF-assisted OSA starches but only by 3 °C for OSA modified starch without PEF treatment as compared to that of native starch. PEF-assisted esterification could reduce the reaction time and improve the reaction efficiency over the control by 6.1-39.1 %. A novel schematic model on structure-functionality relationship for PEF-assisted OSA modified starch was proposed. Structural disorganizations of starch induced lower pasting temperature and paste viscosity. The results suggest that PEF could be a potential eco-friendly and cost-effective physical technique to prepare starch products with desired paste behaviors and to broaden its application area especially in papermaking and textile industries.


Assuntos
Eletricidade , Solanum tuberosum/química , Amido/análogos & derivados , Esterificação , Ligação de Hidrogênio , Estrutura Molecular , Pomadas , Tamanho da Partícula , Amido/química , Relação Estrutura-Atividade , Anidridos Succínicos/química , Temperatura , Viscosidade
3.
Carbohydr Polym ; 237: 116137, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32241438

RESUMO

Enzymatic modification is generally applied to enhance desirable attributes of starch. In this study, ß-cyclodextrin glycosyltransferase (ß-CGTase) together with a specific cyclodextrinase (CDase) was used to modify corn starch. For single ß-CGTase treatment, the molecular weight (Mw) was reduced to 36.7 × 105 g/mol and 7.7 × 105 g/mol for 1 h and 6 h reaction, and the debranched samples had a high proportion of chains with degree of polymerization (DP) < 13, indicating an apparent depolymerization effect. CDase could hardly act on starch, while it had a high preference for cyclodextrin hydrolysis and produced mainly maltotetraose with ß-CGTase. There was a synergistic effect between ß-CGTase and CDase in starch degradation. Interestingly, the utilization of dual-enzyme significantly promoted the retrogradation inhibition property of starch, reducing the retrogradation enthalpy from 5.65 J/g to 1.42 J/g. It was proved that ß-CGTase and CDase had a great prospect in the future application.


Assuntos
Amido/análogos & derivados , Amido/química , Glucosiltransferases/metabolismo , Glicosídeo Hidrolases/metabolismo , Hidrólise , Zea mays/química
4.
Carbohydr Polym ; 235: 115975, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122506

RESUMO

The control of blood flow from breached blood vessels during surgery or trauma is challenging. With the existing treatment options being either expensive or ineffective, the development of a haemostat that overcome such drawbacks would be beneficial. With an aim to develop an ideal haemostat, the potential of sodium starch glycolate (SSG), a commonly used pharmaceutical disintegrant was modified to obtain porous microparticles (pSSG). The biodegradability, cyto-compatibility and haemo-compatibility of the modified particles were confirmed using appropriate studies. In comparison to starch and SSG, the irregular shaped pSSG demonstrated spontaneous and significant fluid absorption (3500+500 %) and formed a physical barrier to blood flow. In addition, significant blood cells aggregation and platelet activation was observed in the modified micoparticles leading to rapid clot formation. In-vivo studies on liver and abdominal artery injury models in rats indicated the superior haemostatic potential of pSSG over SSG and starch. The results indicated that pSSG can be explored further in clinical evaluation as a hemostat.


Assuntos
Hemostáticos/farmacologia , Amido/análogos & derivados , Eritrócitos/efeitos dos fármacos , Hemostáticos/síntese química , Hemostáticos/química , Humanos , Tamanho da Partícula , Agregação Plaquetária/efeitos dos fármacos , Porosidade , Amido/síntese química , Amido/química , Amido/farmacologia , Propriedades de Superfície
5.
Chemosphere ; 244: 125515, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050331

RESUMO

Stable and long-term power output is a prerequisite for the application of the energy recovered from microbial fuel cells (MFCs). In this study, a novel fuel supplying strategy based on slow-release carbon embedded in polymer gels was attempted in MFCs aimed to achieve a sustainable power generation. Polymer gels containing starch acetate as the carbon source (40% (w/w)) were prepared, and the effects of its loading dosage on power generation and microbial community structure were investigated. Results showed that the MFCs once fed with 20.0 g/L, 37.5 g/L and 55.0 g/L polymer gels attained a long-term power generation periods of 110, 140 and 170 days, respectively, with a maximum power density of 386-427 mW/m2. The MFC with a medium loading dosage (37.5 g/L polymer gels) performed best. MFCs fed with the slow-release carbon enriched a distinct microbial community comparing to the control MFC with acetate as the carbon source, with the genera Geobacter, Sphaerochaeta, Christensenellaceae, Aminiphilus and Proteiniphilum significantly enriched on the anode electrode, and Sphaerochaeta, Proteiniphilum and Bacteroidetes in the anolyte. This carbon source providing method will promote the application of MFCs as a sustainable and stable power source for environmental monitoring and remediation.


Assuntos
Fontes de Energia Bioelétrica , Acetatos , Bactérias , Carbono , Eletricidade , Eletrodos , Polímeros , Amido/análogos & derivados
6.
Food Chem ; 315: 126288, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32032833

RESUMO

ß-Carotene was encapsulated in the Pickering emulsions stabilized by chitosan hydrochloride - carboxymethyl starch (CHC-CMS) nanogels. During ultraviolet radiation and storage, the retention of ß-carotene in Pickering emulsions was higher than that of other formulations, such as Tween 80 stabilized emulsions (TEs) and bulk oil. The Pickering emulsions were found to be stable during thermal treatment. Meanwhile, lipid oxidation was delayed in Pickering emulsions compared to TEs and bulk oil. The vitro digestion results suggested that the free fatty acids (FFA) released were below 30% for all Pickering emulsions, which indicated that a physical barrier was formed by CHC-CMS nanogels to restrain the lipid hydrolysis. The bioaccessibility of ß-carotene in Pickering emulsions was higher than that in bulk oil. This research helped establish a connection between the physicochemical properties of CHC-CMS stabilized Pickering emulsions with their applications in the protection effect and oral delivery of bioactive compounds.


Assuntos
Quitosana/química , beta Caroteno/química , Quitosana/análogos & derivados , Emulsões/química , Ácido Clorídrico/química , Hidrólise , Lipídeos/química , Nanogéis/química , Oxirredução , Tamanho da Partícula , Amido/análogos & derivados , Raios Ultravioleta
7.
Food Chem ; 315: 126241, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32014667

RESUMO

Chemical modification with octenyl succinic anhydride (OSA) helps to control the physicochemical and thermal properties of isolated starches. The main objective, herein, was to partially characterize modified starches from Dominico-Harton plantain and FHIA 21 planted in Colombia. The highest degree of substitution was found in FHIA 21 (0.020) starch with 3% OSA and 4-h reaction at room temperature. The grain morphology was not affected, but small changes on the surface were evident. Both modified starches reported absorption bands in the IR at 1566 and 1738 cm-1, proper for these types of starch derivatives. The hexagonal and monoclinic structures of starch were altered through chemical modification. In the bending curves, a drastic decrease in the viscosity of the modified starches was observed with respect to the native one. The gelatinization temperatures of the modified starches were similar to those of the isolated starches.


Assuntos
Plantago/química , Amido/química , Amilose/análise , Colômbia , Microscopia Eletrônica de Varredura , Plantago/crescimento & desenvolvimento , Amido/análogos & derivados , Anidridos Succínicos/química , Viscosidade , Difração de Raios X
8.
J Acad Nutr Diet ; 120(2): 230-244, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32040399

RESUMO

Resistant starch (RS; types 1 to 5) cannot be digested in the small intestine and thus enters the colon intact, with some types capable of being fermented by gut microbes. As a fiber, types 1, 2, 3, and 5 are found naturally in foods, while types 2, 3, and 4 can be added to foods as a functional ingredient. This narrative review identifies RS content in whole foods commonly consumed in the United States. Scientific databases (n=3) were searched by two independent researchers. Ninety-four peer-reviewed articles published between 1982 and September 2018 were selected in which the RS was quantified and the food preparation method before analysis was suitable for consumption. The RS from each food item was adjusted for moisture if the RS value was provided as percent dry weight. Each food item was entered into a database according to food category, where the weighted mean±weighted standard deviation was calculated. The range of RS values and overall sample size for each food category were identified. Breads, breakfast cereals, snack foods, bananas and plantains, grains, pasta, rice, legumes, and potatoes contain RS. Foods that have been cooked then chilled have higher RS than cooked foods. Foods with higher amylose concentrations have higher RS than native varieties. The data from this database will serve as a resource for health practitioners to educate and support patients and clients interested in increasing their intake of RS-rich foods and for researchers to formulate dietary interventions with RS foods and examine associated health outcomes.


Assuntos
Análise de Alimentos , Amido/análise , Pão/análise , Culinária/métodos , Grão Comestível/química , Fabaceae/química , Alimento Funcional/análise , Humanos , Oryza/química , Solanum tuberosum/química , Amido/análogos & derivados , Triticum/química , Estados Unidos
9.
J Sci Food Agric ; 100(6): 2807-2811, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31975414

RESUMO

BACKGROUND: Pickering emulsions are known to have advantages over conventional emulsions, in particular, improved and long-term stability against coalescence. This research is an eight-year stability investigation of oil-in-water Pickering emulsions stabilized by quinoa starch granules modified by octenyl succinic anhydride (OSA). Two different concentrations of starch (i.e. 200 and 600 mg mL-1 based on oil) were used at oil fraction (ϕ) of 0.1. The emulsions were prepared using a high-pressure homogenizer. The emulsions were stored in a refrigerator (at 6 °C) and evaluated using particle size analyzer over the storage period and light microscopy at the end of the storage period. RESULTS: Starch granule stabilized Pickering emulsions produced by a high-pressure homogenizer displayed remarkable storage stability over the eight years with no indication of coalescence. In addition, the results showed that increasing the concentration of starch granules resulted in a decrease in droplet sizes. The sizes measured by the particle size analyzer showed a decline over the storage period which was due to dissociation of some networks of aggregated droplets that, in addition to representing smaller droplet sizes, resulted in the release of free and unbound starch entrapped in these networks. CONCLUSIONS: This study showed that Pickering emulsions produced by OSA modified starch granules from quinoa can be used in practical applications for the development of highly stable formulations when prolonged storage is required. © 2020 Society of Chemical Industry.


Assuntos
Emulsificantes/química , Emulsões , Amido/análogos & derivados , Chenopodium quinoa , Estudos Longitudinais , Tamanho da Partícula , Amido/química , Triglicerídeos/química , Água/química
10.
J Food Sci ; 85(3): 666-672, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31999366

RESUMO

Octenyl succinic anhydride modified sweet potato starch (OSA-SPS) were synthesized in different degrees of substitution (DS) from 0.0073 to 0.0153. Unlike sweet potato starch (SPS), two additional characteristic peaks were detected at 1,572 and 1,724 cm-1 from the Fourier Transform-Infrared spectroscopy in OSA-SPS and their intensities were generally increased with the elevation in DS. Scanning electron microscopy and X-ray diffraction analyses revealed that the esterification did not alter the initial shape of starch granules and mainly occurred on the surface of starch pellets. In addition, OSA-SPS possessed higher transmittance, viscosity and stability, lower gelatinization temperature, and shorter gelatinization time than SPS. The changes of these properties of SPS after the esterification with OSA would be more conducive to its application in food and other fields. PRACTICAL APPLICATION: Octenyl succinic anhydride modified starch (OSAS), as a relatively novel amphiphilic surfactant, have been applied to the processing of many products due to its special hydrophilicity and lipophilicity. The structural and physicochemical properties of sweet potato starch (SPS) and octenyl succinic anhydride modified sweet potato starch (OSA-SPS) with different degrees of substitution (DS) were systematically analyzed in this research. The findings give fundamental understanding of OSA-SPS and provide a basic reference for its application in industries including food, cosmetics, textiles, and so on.


Assuntos
Ipomoea batatas/química , Extratos Vegetais/química , Amido/análogos & derivados , Esterificação , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Anidridos Succínicos/química , Temperatura , Viscosidade
11.
Int J Pharm ; 577: 119080, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31988030

RESUMO

Superdisintegrants are a key excipient used in immediate release formulations to promote fast tablet disintegration, therefore understanding the impact of superdisintegrant variability on product performance is important. The current study examined the impact of superdisintegrant critical material attributes (viscosity for sodium starch glycolate (SSG), particle size distribution (PSD) for croscarmellose sodium (CCS)) on their performance (swelling) and on drug dissolution using surface dissolution UV imaging. Acidic and basic pharmacopoeia (compendial) media were used to assess the role of varying pH on superdisintegrant performance and its effect on drug dissolution. A highly soluble (paracetamol) and a poorly soluble (carbamazepine) drug were used as model compounds and drug compacts and drug-excipient compacts were prepared for the dissolution experiments. The presence of a swelled SSG or CCS layer on the compact surface, due to the fast excipient hydration capacity, upon contact with dissolution medium was visualized. The swelling behaviour of superdisintegrants depended on excipient critical material attributes and the pH of the medium. Drug dissolution was faster in presence compared to superdisintegrant absence due to improved compact wetting or compact disintegration. The improvement in drug dissolution was less pronounced with increasing SSG viscosity or CCS particle size. Drug dissolution was slightly more complete in basic compared to acidic conditions in presence of the studied superdisintegrants for the highly soluble drug attributed to the increased excipient hydration capacity and the fast drug release through the swelled excipient structure. The opposite was observed for the poorly soluble drug as potentially the improvement in drug dissolution was compromised by drug release from the highly swelled structure. The use of multivariate data analysis revealed the influential role of excipient and drug properties on the impact of excipient variability on drug dissolution.


Assuntos
Excipientes/química , Tecnologia Farmacêutica , Raios Ultravioleta , Acetaminofen/química , Carbamazepina/química , Carboximetilcelulose Sódica/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Solubilidade , Amido/análogos & derivados , Amido/química , Comprimidos , Viscosidade
12.
Carbohydr Polym ; 230: 115627, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887941

RESUMO

In this study, chitosan (C) tripolyphosphate (T) sub-micro particles containing ungeremine (CTUn), an alkaloid particularly active against Penicilliumroqueforti, a fungus responsible of the bakery products deterioration, were prepared through external gelation crosslinking process. The particles were included in a thermoplastic starch based polymer Mater-Bi (MBi), and MBi/CTUn bioactive biocomposites were obtained. The films showed bioactivity against P. roqueforti. In particular, the bioassays were performed on films with different concentration of CTUn and at different pH values. CTUn particles influenced MBi crystallization (DSC analysis) and promoted thermal degradation of MBi starch component (TGA). Morphological analysis confirmed even distribution of sub-micro particles into the polymeric matrix. Water permeability slightly increased, as expected, whereas oxygen permeability decreased. Tensile tests showed CTUN sub-microparticles improved rigidity and tensile strength of the films at the expense of ductility. Finally, MBi/CTUn biocomposites evidenced interesting performances potentially exploitablein bioactive bakery based food packaging materials.


Assuntos
Antifúngicos/química , Quitosana/análogos & derivados , Amido/análogos & derivados , Antifúngicos/farmacologia , Embalagem de Alimentos/métodos , Nanocompostos/química , Oxigênio/química , Penicillium/efeitos dos fármacos , Resistência à Tração
13.
Drug Dev Ind Pharm ; 46(1): 42-49, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31794271

RESUMO

The number of Parkinson's disease (PD) patients with the advanced phase and motor fluctuations is increasing. The objective of this study is developing levodopa/benzylhydrazine orally disintegrating tablets (L/B ODTs), which would provide greater convenience and ease of use than conventional tablets for these patients. In the present study, the L/B ODTs were developed successfully with an optimized formulation using response surface methodology (RSM). The direct compression technology was employed for the preparation of L/B ODTs. Considerably shorter disintegration time and faster dissolution profile were obtained under the optimum formulation with microcrystalline cellulose 25.7%, cross-polyvinylpyrrolidone 6.22% and Sodium carboxymethyl starch 5.36%. The content uniformity (%) of levodopa and benzylhydrazine was 50 ± 1.4% and 14.25 ± 0.6%, respectively. Thickness, friability, hardness and wetting time were 2.8 ± 0.05 mm, 0.46 ± 0.21%, 5.42 ± 1.1 kp and 31.2 ± 2.1 s, respectively, and all of data well comply with the General Principles of the Chinese Pharmacopeia. Mannitol of 22% in formulation could bring a pleasant taste: sweet, cool and refreshing. Almost all the volunteers felt that the ODTs had good taste, no roughness, and no gritty feeling, indicating that the ODTs prepared had good palatability, so patients will have good compliance when taking medicine.


Assuntos
Antiparkinsonianos/administração & dosagem , Excipientes/química , Hidrazinas/administração & dosagem , Levodopa/administração & dosagem , Administração Oral , Adulto , Antiparkinsonianos/química , Celulose/química , Química Farmacêutica , Combinação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Hidrazinas/química , Levodopa/química , Masculino , Povidona/química , Amido/análogos & derivados , Amido/química , Comprimidos , Paladar , Tecnologia Farmacêutica , Adulto Jovem
14.
Food Sci Technol Int ; 26(3): 254-264, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31726872

RESUMO

The purpose of this study is to reveal the mechanism of preparing high quality modified starch by ultrasonic technology. In this paper, ultrasonic modified starch and octenyl succinic anhydride modified starch with low degree of substitution were prepared under ultrasonic conditions, using sweet potato starch as raw material. The effects of ultrasound on the structure and properties of native sweet potato starch were studied to see whether ultrasound could produce mechanochemical effect on starch. Then the mechanism of ultrasonic effect on quality of octenyl succinic anhydride modified starch was studied by mechanochemical effect. The results showed that after ultrasonic treatment for 1 min, the crystallinity decreased from 37.6 to 33.8% and reaction efficiency increased from 49.43 to 54.39%, while after ultrasonic treatments for 8 and 32-60 min had different changes. These changes showed that ultrasonic treatment produced significant mechanochemical effect on native sweet potato starch. Ultrasound significantly improved the quality of octenyl succinic anhydride modified starch, and its influence mechanism was revealed using the theory of mechanochemistry. This study provides a feasible method for the research of high quality modified starch and lays a theoretical foundation for expanding the application of ultrasound in various fields.


Assuntos
Manipulação de Alimentos/métodos , Ipomoea batatas/química , Som , Amido/análogos & derivados , Anidridos Succínicos , Humanos , Amido/química
15.
Int J Biol Macromol ; 144: 705-714, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31857164

RESUMO

The impact of starch granule size on 2-octenyl-1-succinic anhydride (OSA) modification remains unclear. To investigate changes of structural, physicochemical, digestibility and emulsifying properties due to OSA modification, five small granule starches (from wheat, rice, oat, quinoa and amaranth) were selected and compared with a standard large granule starch (waxy maize). OSA starches were prepared in 3% (volume by weight) OSA reagent with continuous stirring for 6 h under constant pH of 8.5. The hypothesis was that property changes induced by OSA treatment can be more efficiently achieved in small granule starches (< 10 µm diameter). Small granule OSA starches generally had greater emulsion stability, swelling power and digestibility after gelatinization than waxy maize OSA starch, likely due to the unique physical properties and specific molecular structures of small granule starches, i.e. low sedimentation coefficient, low DP of amylopectin and highly branched amylopectin with short chain length. Granule sizes of OSA starches significantly impact on swelling power, amylose leaching, digestibility and emulsifying capacity, but to different extents depending on botanical origin.


Assuntos
Hidrogéis/química , Amido/análogos & derivados , Amido/química , Anidridos Succínicos/química , Amaranthus/química , Amilopectina/química , Amilose/química , Avena/química , Chenopodium quinoa/química , Emulsões/química , Estrutura Molecular , Oryza/química , Tamanho da Partícula , Amido/síntese química , Relação Estrutura-Atividade , Triticum/química , Água , Zea mays/química
16.
Int J Biol Macromol ; 143: 401-412, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31760022

RESUMO

Copolymer nanoparticles with pH-responsive properties were prepared by grafting different amounts of 2-(dimethylamine) ethyl methacrylate (DMAEMA) on carboxymethyl maize starch (CMS). The formation of CMS-g-DMAEMA was verified by different techniques and was then used for stabilization of Pickering emulsion at different pH values. The CMS-g-DMAEMA nanoparticles showed pH-responsive properties in Pickering emulsion and the pH-responsivity increased as the amount of DMAEMA increased in the CMS-g-DMAEMA copolymer. The prepared Pickering emulsion underwent emulsion/demulsification transitions at different pH values. The microscopy analysis verified the attachment of CMS-g-DMAEMA on oil-water interface of Pickering emulsion. Pickering emulsion showed different droplets size, contact angle, and Zeta-potential depend on pH value and CMS/DMAEMA ratio in the CMS-g-DMAEMA copolymer. The obtained results revealed that CMS-g-DMAEMA copolymer can be successfully used for preparing and stabilizing of Pickering emulsion at pH 10.


Assuntos
Nanopartículas/química , Amido/análogos & derivados , Zea mays/química , Emulsões , Amido/química , Água/química
17.
Food Chem ; 308: 125674, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669944

RESUMO

Cadmium-contaminated rice has been a serious food safety issue in China. In this research, carboxymethyl rice starch (CMS) from cadmium-contaminated rice and native rice was prepared to remove the cadmium in rice. The preparation of native rice starch (NRS) and starch from cadmium-contaminated rice (Cd-CRS) was similar, and carboxymethyl starch was prepared following the same steps. A single factor experiment was performed to obtain the carboxymethyl starch prepared under the optimal conditions. Cadmium content was reduced from 0.38 mg/kg to 0.04 mg/kg after alkalization. The physical properties, including particle size, degree of crystallinity, water absorption and freeze-thaw stability, of NRS and Cd-CRS and their carboxymethyl starches were studied. The results showed that the cadmium was significantly removed after extracting starch from cadmium-contaminated rice by alkalization and carboxymethylation. Then, starch samples and carboxymethyl starch samples were characterized. All results showed no obvious difference between Cd-CMS and NCMS, indicating that carboxymethyl starch from cadmium-contaminated rice could be widely used in both food and nonfood industries.


Assuntos
Cádmio/análise , Oryza/química , Amido/análogos & derivados , Contaminação de Alimentos , Inocuidade dos Alimentos , Tamanho da Partícula , Amido/química , Água
18.
Food Chem ; 303: 125391, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466030

RESUMO

Sunflower oil-in-water Pickering emulsions were fabricated using octenyl succinic anhydride (OSA) modified starch particles and small molecular surfactants (e.g., SDS, CTAB and Tween 20) as stabilizers. Emulsions were characterized for physical stabilities by cream volume, droplet size distribution and microstructure. Oxidative stabilities of the emulsions were investigated by accelerated oxidation tests at 50 °C. Results showed that cream volumes had little difference after 14 days of storage, while the droplet sizes of emulsions stabilized by starch particles and surfactants decreased greatly compared to those only with starch particles (p < 0.05). Droplet microstructure revealed that small molecular surfactants competed with starch particles for the adsorption at interface. The emulsion stabilized by 1.0% OS-starch particle and 1.0% SDS had the lowest peroxide value and acid value. These findings implied that starch particles were compatible with anionic surfactants and could enhance the stabilities and decrease the oxidation rate of Pickering emulsions.


Assuntos
Emulsões/química , Amido/análogos & derivados , Oxirredução , Amido/química , Óleo de Girassol/química , Tensoativos/química , Água/química
19.
Polim Med ; 49(1): 19-26, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31756060

RESUMO

BACKGROUND: Sugar substitutes are used by diabetic, obese and calorie-conscious people. As artificial sweeteners are harmful to the body, natural sweeteners are more suitable. Sugar substitutes are available on the market in tablet forms, which are added to hot or cold drinks. Rapid disintegration and dissolution of sugar substitute-loaded tablet is desired. However, the tablets should be hard enough to maintain their integrity during mechanical shocks. OBJECTIVES: The objective of this research was to develop rapidly disintegrating and dissolving stevia-loaded tablets with appropriate wetting, hardness and friability. MATERIAL AND METHODS: Several tablets were prepared using different superdisintegrants using the direct compression method. Flowability tests of the powder blends were performed before compression; these test took into account such physical parameters as bulk density, tapped density, angle of repose, compressibility index, and Hausner's ratio. Evaluation of the compressed cores was accomplished with weight variation, hardness, thickness, friability, disintegration time, wetting time, and dissolution. RESULTS: The disintegration time and wetting time of the tablets were in the following order: sodium starch glycolate > croscarmellose sodium > crospovidone containing tablets. A powder blend consisting of stevia extract, crospovidone, lactose, and magnesium stearate at the optimized ratio of 15/2.5/32/0.5 (w/w/w/w) showed the best flow, rapid disintegration (38 ±0.894 s), wetting (30 ±1 s), and dissolution (~ 95% in 1 min). Moreover, this formulation showed more rapid wetting (30 ±1 s vs 91 ±1.9 s), disintegration (38 ±0.894 s vs 143 ±1.276 s) and dissolution (~ 95% vs 60% in 1 min) than a commercial product. CONCLUSIONS: The tablet consisting of stevia, crospovidone, lactose, and magnesium stearate at the weight ratio of 15/2.5/32/0.5 showed excellent results with regards to dissolution and disintegration; accordingly, this formulation could be a potential sugar substitute for diabetic, obese and/or calorie-conscious individuals.


Assuntos
Povidona , Stevia , Carboximetilcelulose Sódica , Química Farmacêutica , Dureza , Humanos , Solubilidade , Amido/análogos & derivados , Comprimidos
20.
Int J Pharm ; 572: 118801, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678529

RESUMO

This study was aimed to monitor the transit through the intestine by X-ray imaging using barium sulfate (BS) as tracer. The in vitro features of monolithic tablets were correlated with their in vivo behavior in order to provide a tool for the development of targeted formulations containing macromolecular bioactive agents. The impact of BS on various matrices (neutral, ionic) was studied in simulated fluids using the disintegration time (DT) as main parameter. Dry tablets were characterized by spectroscopic methods (X-ray diffraction and Infra-Red) and scanning electron microscopy (SEM). The selected formulations were followed in a beagle dog model. The in vivo and in vitro DT of tablets formulated with BS were compared. Results: anionic excipients carboxymethylcellulose (CMC) and carboxymethylstarch (CMS) protected the active ingredient from the gastric acidity, ensuring its targeted delivery in the intestine. The SEM analysis, before and after transit in simulated fluids, showed that BS remained in the tablets allowing their good follow-up in vivo. The incorporation of 30% protein in tablets with 40% BS had no impact on their behavior. In conclusion, BS and X-ray imagery could be a good alternative to scintigraphy for development of targeted formulations containing high molecular weight bioactive agents.


Assuntos
Sulfato de Bário/administração & dosagem , Carboximetilcelulose Sódica/química , Meios de Contraste/administração & dosagem , Excipientes/química , Intestinos/diagnóstico por imagem , Soroalbumina Bovina/administração & dosagem , Amido/análogos & derivados , Animais , Sulfato de Bário/química , Meios de Contraste/química , Cães , Composição de Medicamentos , Liberação Controlada de Fármacos , Suco Gástrico/química , Trânsito Gastrointestinal , Concentração de Íons de Hidrogênio , Secreções Intestinais/química , Soroalbumina Bovina/química , Amido/química , Comprimidos , Fatores de Tempo
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