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1.
Pharm Nanotechnol ; 12(4): 365-377, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38192139

RESUMO

BACKGROUND: Orally disintegrating tablets (ODTs) have become an excellent choice for delivering drugs as their palatability is greatly improved. In this work, ß-cyclodextrin has been used to improve the solubility of curcumin by encapsulating it into the hydrophobic cavity for the treatment of neurodegenerative disorders. OBJECTIVES: The current study aimed to present the design, formulation, and optimisation of fastdissolving oral tablets of curcumin- ß-cyclodextrin molecular inclusion complex using a 32-factorial design. METHODS: The drug-excipient compatibility was studied by FTIR spectroscopy. The inclusion complex of curcumin-ß-cyclodextrin was prepared using solvent casting and confirmed using XRD studies. Powder blends were evaluated for flow properties. Tablets prepared by direct compression were evaluated for post-compression parameters. Further, the effect of formulation variables, such as sodium starch glycolate (X1) and Neusilin® ULF2 (X2), on various responses, including disintegration time and dissolution at 2 hours, was studied using statistical models. RESULTS: Post-compression parameters, i.e., hardness (4.4-5 kg/cm2), thickness (3.82-3.93 mm), weight variation (±7.5%), friability (< 1%), wetting time (51-85 seconds) and drug content (96.28- 99.32%) were all found to be within the permissible limits and the disintegration time of tablets with super-disintegrants ranged between 45-58 seconds. The in-vitro dissolution profile of tablets showed that higher SSG and Neuslin® ULF2 levels promoted drug release. For statistical analysis, the 2FI model was chosen. Optimised variables for formulation have been determined and validated with the experimental findings based on the significant desirability factor. CONCLUSION: The current study reveals the validated curcumin-ß-cyclodextrin inclusion complex fastdissolving tablets with SSG and Neusilin® ULF2 to be an ideal choice for effectively treating neurodegenerative disorders.


Assuntos
Curcumina , Doenças Neurodegenerativas , Solubilidade , Comprimidos , Água , beta-Ciclodextrinas , Curcumina/química , Curcumina/administração & dosagem , beta-Ciclodextrinas/química , Água/química , Doenças Neurodegenerativas/tratamento farmacológico , Excipientes/química , Liberação Controlada de Fármacos , Amido/química , Amido/análogos & derivados , Composição de Medicamentos/métodos , Administração Oral , Dureza , Interações Hidrofóbicas e Hidrofílicas , Humanos , Portadores de Fármacos/química
2.
Int J Biol Macromol ; 257(Pt 1): 128804, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38101664

RESUMO

In this paper, using a coprecipitation method to prepare Fe3O4 magnetic nanoparticles (Fe3O4 MNPS), magnetic dialdehyde starch nanoparticles with immobilized phospholipase A1 (MDSNIPLA) were successfully prepared by using green dialdehyde starch (DAS) instead of glutaraldehyde as the crosslinking agent. The Fe3O4 MNPS was characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), the Brunauer-Emmett-Teller (BET) surface area analysis method, thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) et al. The results showed that the alkaline resistance and acid resistance of the enzyme were improved after the crosslinking of DAS. After repeated use (seven times), the relative activity of MDSNIPLA reached 56 %, and the magnetic dialdehyde starch nanoparticles (MDASN) had good carrier performance. MDSNIPLA was applied to enzymatic hydrolysis of phospholipids in the soybean oil degumming process. The results showed that the acyl transfer rate of sn-2-HPA was 14.01 %, and the content of free fatty acids was 1.144 g/100 g after 2 h reaction at 50 °C and pH 5.0 with appropriate boric acid. The immobilized enzyme has good thermal stability and storage stability, and its application of soybean oil improves the efficiency of the oil.


Assuntos
Enzimas Imobilizadas , Óleo de Soja , Amido/análogos & derivados , Espectroscopia de Infravermelho com Transformada de Fourier , Enzimas Imobilizadas/química , Fosfolipases , Fenômenos Magnéticos
3.
J Sci Food Agric ; 102(14): 6373-6386, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35535559

RESUMO

BACKGROUND: Catechins, a member of the flavonoids, exist widely in teas, and have health benefits. However, catechins have poor stability, which greatly limits their application. In order to improve the stability of catechins, different catechins including (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG) were conjugated onto dialdehyde starch by acid-mediated coupling method. The structure, stability and antioxidant activity of dialdehyde starch-catechin conjugates were determined. RESULTS: Thin-layer chromatography and ultraviolet-visible spectroscopy, fluorescence, nuclear magnetic resonance and infrared spectra revealed that catechins were successfully conjugated onto dialdehyde starch, coupling between 6-H/8-H of catechins' A ring and dialdehyde starch's aldehyde groups. The conjugates presented an amorphous structure and sheet-like and/or blocky morphologies. As compared to dialdehyde starch, the conjugates showed enhanced thermal stability. Furthermore, the stability of catechins in pH 7.4 phosphate-buffered saline was improved after conjugating onto dialdehyde starch. The conjugates exhibited significantly higher antioxidant activities than dialdehyde starch, decreasing in the following order: dialdehyde starch-ECG, dialdehyde starch-EGCG, dialdehyde starch-EC, dialdehyde starch-EGC and dialdehyde starch. CONCLUSION: Dialdehyde starch-catechin conjugates have great potential as stable antioxidant agents. © 2022 Society of Chemical Industry.


Assuntos
Catequina , Aldeídos/análise , Antioxidantes/análise , Catequina/análogos & derivados , Catequina/química , Flavonoides/análise , Fosfatos , Amido/análogos & derivados , Chá/química
4.
Int J Biol Macromol ; 186: 820-828, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280445

RESUMO

Recently, food industries are directing on the promotion of innovative food matrices fortified with bioactive compounds in order to enhance the consumer's health. Octenyl succinic anhydride modified starches (OSA-MS) such as Hi-cap100 (HCP) and purity gum 2000 (PUG) were used to fabricate emulsions co-entrapped with borage seed oil (BSO), resveratrol (RES) and curcumin (CUR), which were further spray dried to obtain powders. The fabricated microcapsules loaded with BSO, RES, and CUR displayed excellent dissolution performance, high encapsulation efficiency (≈93.05%) as well as semi-spherical shape, revealed via scanning electron microscopy (SEM). We also evaluated the impact of storage time (4 weeks) and temperature (40 °C) on the physicochemical characterization of OSA-MS coated microcapsules. Microcapsules coated with HCP exhibited greater oxidative stability, lower water activity and moisture contents rather than PUG coated microcapsules during storage because of its good film-forming properties. Addition of CUR enhanced the oxidative stability and retention of bioactive compounds. HCP microcapsules loaded with BSO + RES + CUR presented supreme retention of RES (70.32%), CUR 81.6% and γ-linolenic acid (≈ 96%). Our findings showed that CUR acted as an antioxidant agent; also, lower molecular weight OSA-MS as wall material could be used for the entrapment of bioactive compounds and promotion of innovative food products.


Assuntos
Antioxidantes/química , Curcumina/química , Portadores de Fármacos , Nanopartículas , Óleos de Plantas/química , Resveratrol/química , Amido/química , Ácido gama-Linolênico/química , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Emulsões , Nanotecnologia , Oxirredução , Pós , Secagem por Atomização , Amido/análogos & derivados , Fatores de Tempo
5.
Molecules ; 26(8)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920373

RESUMO

The study focused on the influence of starch modified by octenyl succinic anhydride (OSA) on the rheological and thermal properties of gluten-free dough containing corn and potato starch with the addition of pectin and guar gum as structure-forming substances. The starch blend used in the original dough recipe was partially (5% to 15%) replaced with OSA starch. The rheological properties of dough samples were determined, and the properties of the resulting bread were analyzed. It was found that the dough samples behaved as weak gels, and the values of storage and loss moduli (G' and G″, respectively) significantly depended on angular frequency. Various shares of OSA starch in recipes modified dough in different ways, causing changes in its rheological characteristics. The introduction of OSA starch preparations resulted in changes in the bread volume and physical characteristics of the crumb. All the applied preparations caused an increase in bread porosity and the number of pores larger than 5 mm, and there was a parallel decrease in pore density. The presence of OSA starch preparations modified bread texture depending on the amount and type of the applied preparation. The introduction of OSA starches in gluten-free bread formulation caused a significant drop in the enthalpy of retrograded amylopectin decomposition, indicating a beneficial influence of such type of additive on staling retardation in gluten-free bread.


Assuntos
Pão/análise , Tecnologia de Alimentos/métodos , Galactanos/química , Mananas/química , Pectinas/química , Gomas Vegetais/química , Amido/análogos & derivados , Culinária/métodos , Dieta Livre de Glúten , Humanos , Porosidade , Reologia , Amido/química , Zea mays/química
6.
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
7.
Carbohydr Polym ; 243: 116499, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32532383

RESUMO

Medium-substituted esters of starch and higher fatty acids, structurally identified in the first part of paper were subjected to further analyses, mainly to check application potential. In order to determine the possibility of using the esters in the packaging industry, the glycerol-plasticized starch esters were extruded on a single screw extruder in the form of a film. The mechanical properties tests consisted of tensile and tear strength. Hydrophobicity, water absorption and oil absorption were checked as the processing and functional properties. Environmental tests, such as phytotoxicity on monocotyledonous and dicotyledonous plants and biodegradability in soil under strictly controlled conditions of the vegetation hall were carried out. Esterification increased the hydrophobicity of the starch and the tensile and tear strength, without losing important environmental features such as biodegradability and non-toxicity. The obtained polymer materials give hope for their use in the production of new ecofriendly and biodegradable packaging.


Assuntos
Óleos de Plantas/química , Embalagem de Produtos , Amido , Interações Hidrofóbicas e Hidrofílicas , Amido/análogos & derivados , Amido/química , Resistência à Tração
8.
Int J Biol Macromol ; 151: 702-712, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32092424

RESUMO

This investigation aims to evaluate the synergistic effects of amorphous OSA-modified starch, unsaturated lipid-carrier (RBD-SFO), and high-energy microfluidization in synergy with the ultrasonic techniques in fabricating of Lavandula angustifolia essential oil (LAF-EO) nanoparticle. GC-MS and SEM techniques were employed to investigate the LAF-EO isolation method used. DLS analysis was employed along with CLSM and TEM techniques to investigate the physicochemical properties of nanoemulsion formulation (NE) matrices. The NE achieved the optimal spherical and size distributions of droplets (125.7 nm), Poly Dispersity Index (PdI) (0.183), and ζ-potential (-40.3 mV) when the contents of the formulation matrix were as follows: OSA-MS (2%), LAF-EO (1%), RBD-SFO (1%), and Tween-80 (1%). The findings of this work provide a new concept about the synergistic effects of amorphous OSA-modified starch and unsaturated lipid carrier as safe-grade macromolecules in the fabricating of LAF-EO nanoparticles. Besides, the application of the ultrasound cavitation phenomenon has been shown to have effective effect in reducing the droplet hydrodynamic diameter along with enhancing the distribution (PdI) and electrokinetic potential of the LAF-EO nanoparticles.


Assuntos
Lipídeos/química , Nanopartículas/química , Óleos Voláteis/química , Amido/análogos & derivados , Ondas Ultrassônicas , Fenômenos Químicos , Emulsões , Micro-Ondas , Oxirredução , Tamanho da Partícula , Análise Espectral , Amido/química , Tensoativos/química
9.
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
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.
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
12.
Food Funct ; 10(9): 5446-5460, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31403644

RESUMO

A high internal phase emulsion (HIPE) was firstly fabricated with octenyl succinic anhydride modified starch through simple shear dispersion. The impact of the emulsifier level, pH, and ionic strength on the rheology, microstructure, interfacial properties, water binding and thermal stability of the HIPE was determined. The results indicated that HIPEs could be formed at a suitably modified starch concentration (≥3 wt%), a wider range of pH (3 to 7) and all test salt levels (0 to 400 mM NaCl). Encapsulation of a sensitive hydrophobic nutraceutical (ß-carotene) within the HIPEs could improve its chemical stability under UV exposure, and the degradation ratio was fairly similar at all test pH values. The ß-carotene stability and bioaccessibility during in vitro digestion were improved by encapsulation into HIPEs, but their values depended on pH to some extent. These results are useful for designing and fabricating modified starch-stabilized HIPEs which can be utilized in functional food and pharmaceutical applications.


Assuntos
Composição de Medicamentos/métodos , Óleos de Plantas/química , Amido/análogos & derivados , beta Caroteno/química , Camellia/química , Composição de Medicamentos/instrumentação , Estabilidade de Medicamentos , Emulsificantes/química , Emulsões/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Reologia , Amido/química
13.
Food Chem ; 295: 466-474, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174783

RESUMO

Physicochemical properties and emulsion stability of octenyl succinic anhydride (OSA)-modified partial waxy rice Baegjinju starches which were made with different OSA additions and the color stability of the encapsulated paprika pigment powder using the OSA starch were investigated. The DSs of the OSA starches ranged from 0.0152 to 0.0269. The band at 3303 cm-1 reduced as the OSA levels increased, but the A-type crystallinity was maintained. The oil absorption and emulsion stability, the short chain (DP6-12) amylopectin, the resistant starch levels, and the peak and final viscosities increased as the OSA levels increased. The encapsulated pigment powder with freeze-drying had higher color stability and better emulsion, and heating stabilities occurred with spray drying and the native pigment. From these results, it is suggested that the OSA-modified Baegjinju rice starch is a good wall material to protect lipophilic carotenoids. The encapsulated pigment powders could be used as stable natural colorants.


Assuntos
Capsicum/química , Oryza/química , Pigmentos Biológicos/química , Amido/análogos & derivados , Amilopectina , Emulsões/química , Liofilização , Extratos Vegetais/química , Pós/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Viscosidade
14.
Food Chem ; 288: 291-296, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902296

RESUMO

Potato starch was pre-treated with CaCl2 solutions prior to modification with octenyl succinic anhydride (OSA). Starch pre-treated with 1.0 M CaCl2 showed higher degree of substitution (DS) and reaction efficiency (RE) on OSA modification, whereas pre-treatment with CaCl2 solutions at 0.05 M, 0.1 M and 0.5 M had no effect on DS and RE. CaCl2 pre-treatment decreased the swelling power, paste clarity, peak viscosity (PV), breakdown (BD) and some textural parameters of potato starch, with the effects being greater at higher concentrations of CaCl2. Pre-treatment with 1.0 M CaCl2 caused a small disruption to starch crystallinity and granule morphology. OSA modification significantly decreased the textural parameters, PV, BD, relative crystallinity, swelling power, gelatinization temperatures and enthalpy of potato starch, but it increased the paste clarity and emulsifying activity. OSA-1.0 M-starch showed improved functional properties over OSA-starch, indicating that CaCl2 pre-treatment provides advantages for improving the functional characters of succinylated starch.


Assuntos
Cloreto de Cálcio/química , Solanum tuberosum/metabolismo , Amido/química , Succinatos/química , Varredura Diferencial de Calorimetria , Emulsões/química , Amido/análogos & derivados , Temperatura , Viscosidade , Difração de Raios X
15.
Appl Microbiol Biotechnol ; 103(5): 2367-2379, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30675636

RESUMO

High-throughput function-based screening techniques remain the major bottleneck in the novel biocatalysts development pipeline. In the present study, we customized protocols for amylolytic activity determination (Somogyi-Nelson and starch-iodine tests) to micro-volume thermalcycler-based assays (linearity range 60-600 µM of reducing sugar, R2 = 0.9855; 0-2 mg/mL of starch, R2 = 0.9921, respectively). Exploitation of a thermalcycler enabled rapid and accurate temperature control, further reduction of reagents and samples volumes, and limited evaporation of the reaction mixtures, meeting several crucial requirements of an adequate enzymatic assay. In the optimized micro-volume Somogyi-Nelson protocol, we were able to reduce the time required for high-temperature heating sixfold (down to 5 min) and further increase sensitivity of the assay (tenfold), when compared to the previous MTP-based protocol. The optimized microassays have complementary scope of specificities: micro-starch-iodine test for endoglucanases, micro-Somogyi-Nelson test for exoglucanases. Due to rapid, micro-volume and high-throughput character, the methods can complement toolbox assisting development of novel biocatalysts and analysis of saccharides-containing samples.


Assuntos
Ensaios Enzimáticos/métodos , Ensaios de Triagem em Larga Escala/métodos , alfa-Amilases/metabolismo , Celulase/metabolismo , Glucana 1,4-alfa-Glucosidase/metabolismo , Temperatura Alta , Amido/análogos & derivados , Amido/metabolismo
16.
Int J Biol Macromol ; 124: 582-590, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30502427

RESUMO

In this work, a multielement compound fertilizer (MCF) was fabricated using ammonium zinc phosphate (AZP) as kernel nutrient element, and polydopamine (Pdop) film as inner coating. Besides, sodium carboxymethyl starch (SCS) was proposed as a constituent in AZP@Pdop mixture due to its adhesion, gelling and swelling abilities, to prepare well dispersed suspensions and consolidate the single-coated fertilizer. What's more, iron (Fe), the vital microelement for the growth of crops and alleviating the leaf chlorosis, was chelated by the carboxylate groups of SCS, contributing to make the outer coating compact. The release behavior showed that zinc (Zn), phosphorus (P) and Fe reached 60% cumulative release in 30 days, and the use efficiency of nutrients for corn was about 60%. In summary, this work provides a novel approach to improve the utilization efficiency and prolong duration of the MCF, which might have a potential application in agronomics.


Assuntos
Fertilizantes , Indóis , Polímeros , Compostos de Sódio , Amido/análogos & derivados , Compostos de Amônio/química , Produtos Agrícolas , Fertilizantes/análise , Indóis/química , Fosfatos/química , Fósforo , Polímeros/química , Compostos de Sódio/química , Solo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Termogravimetria , Zea mays , Zinco , Compostos de Zinco/química
17.
Int J Biol Macromol ; 116: 224-231, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29730009

RESUMO

A controlled release fertilizer system based on phosphate bound-carboxymethyl starch-graft-polyacrylamide (P-CMS-g-PAM) has been prepared in order to deliver the phosphate fertilizer to the plant at a constant rate thereby. This system aims to increase fertilizer phosphorus use efficiency (FPUE) and maintain a hydration level for the plant at the same time. Two types of starch phosphate monoesters were prepared using mono-ammonium (MAP) and di-ammonium phosphate (DAP). First, starch was converted to carboxymethyl starch and then was phosphorylated with mono-ammonium dihydrogen phosphate and di-ammonium dihydrogen phosphate. After phosphorylation, the samples were grafted with acrylamide in the presence of methylene bisacrylamide as a crosslinking agent. The prepared systems of P-CMS-g-PAM were differently characterized by Fourier transformer infrared (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM) and phosphorous analysis. The swelling behavior was investigated. The kinetics of grafting reaction were also studied. The release behavior of phosphate bound was studied at pH 7 and 25 °C. The mechanism of the phosphate release from P-CMS-g-PAM was examined using the Korsmeyer-Peppas model.


Assuntos
Resinas Acrílicas/química , Preparações de Ação Retardada/química , Fósforo/química , Amido/análogos & derivados , Fertilizantes , Microscopia Eletrônica de Varredura/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Amido/química , Temperatura , Termogravimetria/métodos
18.
Ann N Y Acad Sci ; 1398(1): 47-61, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28445585

RESUMO

The C-type starches are widely distributed in seeds or rhizomes of various legumes, medicinal plants, and crops. These carbohydrate polymers directly affect the application of starchy plant resources. The structural and crystal properties of starches are crucial parameters of starch granules, which significantly influence their physicochemical and mechanical properties. The unique crystal structure consisting of both A- and B-type polymorphs endows C-type starches with specific crystal adjustability. Furthermore, large proportions of resistant starches and slowly digestible starches are C-type starches, which contribute to benign glycemic response and proliferation of gut microflora. Here, we review the distribution of C-type starches in various plant sources, the structural models and crystal properties of C-type starches, and the behavior and functionality relevant to modified C-type starches. We outline recent advances, potential applications, and limitations of C-type starches in industry, aiming to provide a theoretical basis for further research and to broaden the prospects of its applications.


Assuntos
Proliferação de Células/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Amido/química , Amilose/química , Cristalografia por Raios X , Humanos , Hidrólise , Estrutura Molecular , Sementes/química , Amido/análogos & derivados , Amido/metabolismo , Amido/farmacologia , Zea mays/química
19.
J Microencapsul ; 33(8): 773-784, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27927052

RESUMO

The objective of the study was to optimise the encapsulation of Michelia alba D.C. (MAD) extract using octenyl succinic anhydride (OSA) starch. The MAD extract (5-10 g/100 g of dry starch) and the OSA starch (25-100 g/100 ml of water) was used in microcapsule preparation and analysed for the physicochemical and encapsulation properties. The optimised formula using the MAD extract and the OSA starch were 15.00 g/100 g of dry starch and 96.32 g/100 g water, which provided the highest in yield recovery (40.65% ± 0.99) and encapsulation efficiency (68.91% ± 1.50), with the lowest moisture content (3.19% ± 0.06) and water activity (0.236 ± 0.004). The aroma release from the optimum encapsulated powder in simulated artificial saliva fluid (SSF) suggested that linalool retention in microcapsules was higher than verbenone and 2-methyl butanoic acid. This study shows that the optimised formulation of MAD encapsulated flavour powder was found to be effective for controlling the aroma release.


Assuntos
Preparações de Ação Retardada/química , Aromatizantes/administração & dosagem , Magnoliaceae/química , Odorantes , Extratos Vegetais/administração & dosagem , Amido/análogos & derivados , Anidridos Succínicos/química , Aromatizantes/química , Odorantes/análise , Extratos Vegetais/química
20.
Food Chem ; 212: 453-9, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27374555

RESUMO

Native potato starch (PS) granules were separated into three size fractions: larger than 30µm (P-L), 15-30µm (P-M), and smaller than 15µm (P-S). The morphological and crystalline structure of fractionated potato starches were investigated by light and scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The P-L fraction showed ellipsoidal shape and B-type X-ray pattern, whereas the P-S fraction had spherical shape and A-type pattern. The fluorophore-assisted capillary electrophoresis data showed that the P-L fraction had more B2 chains and less short A and B1 chains than the P-S counterparts. Smaller granules with larger specific surface area had higher degree of substitution when reacted with octenylsuccinic anhydride (OSA), and showed more uniform distribution of octenylsuccinate substituents. Both OSA modified and unmodified P-S samples showed higher flowability compared with the P-L counterparts.


Assuntos
Solanum tuberosum/química , Amido/análogos & derivados , Difração de Raios X , Eletroforese Capilar , Microscopia Eletrônica de Varredura , Amido/análise , Amido/química , Difração de Raios X/métodos
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