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1.
Int J Biol Macromol ; 258(Pt 2): 128864, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158059

RESUMO

Starch a natural polymer, has made significant advancements in recent decades, offering superior performance and versatility compared to synthetic materials. This review discusses up-to-date diverse applications of starch gels, their fabrication techniques, and their advantages over synthetic materials. Starch gels renewability, biocompatibility, biodegradability, scalability, and affordability make them attractive. Also, advanced theoretical foundations and emerging industrial technologies could further expand their scope and functions inspiring new applications.


Assuntos
Indústrias , Amido , Géis
2.
World J Gastrointest Surg ; 15(11): 2463-2469, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38111774

RESUMO

BACKGROUND: Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer. The examination of high-risk recurrence factors post-surgery provides critical insights for disease evaluation and treatment planning. AIM: To explore the relationship between metastasis-associated factor-1 in colon cancer (MACC1) and vacuolar ATP synthase (V-ATPase) expression in colon cancer tissues, and recurrence rate in patients undergoing radical colon cancer surgery. METHODS: We selected 104 patients treated with radical colon cancer surgery at our hospital from January 2018 to June 2021. Immunohistochemical staining was utilized to assess the expression levels of MACC1 and V-ATPase in these patients. RESULTS: The rates of MACC1 and V-ATPase positivity were 64.42% and 67.31%, respectively, in colon cancer tissues, which were significantly higher than in paracancerous tissues (P < 0.05). Among patients with TNM stage III, medium to low differentiation, and lymph node metastasis, the positive rates of MACC1 and V-ATPase were significantly elevated in comparison to patients with TNM stage I-II, high differentiation, and no lymph node metastasis (P < 0.05). The rate of MACC1 positivity was 76.67% in patients with tumor diameters > 5 cm, notably higher than in patients with tumor diameters ≤ 5 cm (P < 0.05). We observed a positive correlation between MACC1 and V-ATPase expression (rs = 0.797, P < 0.05). The positive rates of MACC1 and V-ATPase were significantly higher in patients with recurrence compared to those without (P < 0.05). Logistic regression analysis revealed TNM stage, lymph node metastasis, MACC1 expression, and V-ATPase expression as risk factors for postoperative colon cancer recurrence (OR = 6.322, 3.435, 2.683, and 2.421; P < 0.05). CONCLUSION: The upregulated expression of MACC1 and V-ATPase in colon cancer patients appears to correlate with clinicopathological features and post-radical surgery recurrence.

3.
Food Chem ; 404(Pt B): 134549, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283307

RESUMO

Enzymatic browning has been a significant factor affecting the sale of fresh noodles. This study used a combination of physical and chemical methods to achieve a long-lasting and effective anti-browning effect in fresh noodles. The results showed that the combinations of citric acid (CA), NaOH, and KOH with heat treatment blunted the polyphenol oxidase activity and improved the color of fresh noodles. Specifically, the L* value of fresh noodles stored at 6 °C treated by the combination of CA and 75 °C (CHFN-75) at 72 h (81.71) was significantly higher than that of the control at 72 h (74.42). Mixolab and confocal laser scanning microscopy showed that the combined treatment affected the protein and starch of the flour. However, the hardness and chewiness of the cooked noodles increased only slightly, and the adhesiveness decreased slightly. The innovative combination can be used as an effective way to delay the darkening of fresh noodles.


Assuntos
Temperatura Alta , Triticum , Farinha/análise , Culinária , Amido
4.
Psychoradiology ; 2(4): 146-155, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38665276

RESUMO

Alcohol use disorder (AUD) is a worldwide problem and the most common substance use disorder. Chronic alcohol consumption may have negative effects on the body, the mind, the family, and even society. With the progress of current neuroimaging methods, an increasing number of imaging techniques are being used to objectively detect brain impairment induced by alcoholism and serve a vital role in the diagnosis, prognosis, and treatment assessment of AUD. This article organizes and analyzes the research on alcohol dependence concerning the main noninvasive neuroimaging methods, structural magnetic resonance imaging, functional magnetic resonance imaging, and electroencephalography, as well as the most common noninvasive brain stimulation - transcranial magnetic stimulation, and intersperses the article with joint intra- and intergroup studies, providing an outlook on future research directions.

5.
Food Chem ; 309: 125767, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31711811

RESUMO

This study explored the impact of re-acetylation on induced electric field (IEF)-assisted hydrolysis of chitosan. Chitosan with different degree of deacetylation (DD) exhibited different charge content but similar electrical conductivity and output voltage of the electrolyte system, thus theoretically resulting in equivalent electro-processing efficiency. However, molecular and rheological measurements suggested that the hydrolysis rate decreased with an increase of DD. Re-acetylation had no significant effect on the molecular weight and viscosity of chitosan but damaged its granular and crystal structure, making chitosan chains more susceptible to the acid. The IEF-assisted hydrolysis of dissolved chitosan confirmed that the structural compactness of chitosan played a more important role on the hydrolysis than the charge content. This study extended current knowledge regarding the effect of charge content and structural compactness on IEF-assisted hydrolysis process, which contributed to the applications of IEF in biopolymer modification.


Assuntos
Ácidos/química , Quitosana/química , Acetilação , Cristalização , Condutividade Elétrica , Hidrólise , Microscopia Eletrônica de Varredura , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade
6.
Int J Biol Macromol ; 137: 697-702, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31276727

RESUMO

The physicochemical and cooking properties of wheat starch isolated from alkaline yellow dough treated with sodium carbonate (Na2CO3; 0-3.2 g/100 g) were investigated. With increasing Na2CO3 addition, swelling power increased from 7.28 to 10.70 g/g. X-ray diffraction showed no changes in crystalline patterns while the relative crystallinity decreased from 30.11% to 23.13%. Differential scanning calorimetry results suggested that alkaline salt shifted the gelatinization peak of starch to higher temperatures. The values of pasting viscosity and pasting temperature in alkali-treated starch increased and decreased, respectively. Farinograph results revealed the strengthened structure of dough with alkali-treated starch that was manifested by an increase in the dough development time and dough stability time. Cooking loss and rehydration values of noodles prepared from alkali-treated starch increased by 42% and 36%, respectively. The results suggested that Na2CO3 affected starch crystalline structure, swelling power, gelatinization, pasting properties, starch-gluten interactions and cooking characteristics of noodle products.


Assuntos
Carbonatos/química , Fenômenos Químicos , Culinária , Farinha/análise , Qualidade dos Alimentos , Amido/química , Concentração de Íons de Hidrogênio
7.
Food Chem ; 265: 18-22, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29884370

RESUMO

Properties of starches isolated from soft and hard wheat dough after freezing/thawing (F/T) treatment were investigated. Significance of results was observed between isolated hard wheat starch (HWS) and soft wheat starch (SWS), but both cultivars showed an increase in the amounts of damaged starch and leaching proteins, lipids, and amylose with F/T cycles. The freezing-treated HWS exhibited a higher swelling power and peak, trough, breakdown and final viscosity than SWS after F/T treatment. The onset, peak and conclusion gelatinization temperatures and the enthalpy of the isolated HWS determined by differential scanning calorimetry, decreased throughout F/T cycles. Concomitantly, the bread containing freezing-treated HWS exhibited a lower bread specific volume and harder crumb firmness, which might be associated with its significant structural changes induced by F/T treatment.


Assuntos
Congelamento , Amido/química , Triticum/química , Amilose/análise , Pão , Dureza , Amido/metabolismo , Temperatura , Viscosidade
8.
J Food Drug Anal ; 26(2): 688-695, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29567239

RESUMO

The serious cytotoxicity of tyramine attracted marked attention as it induced necrosis of human intestinal cells. This paper presented a novel and facile high performance thin-layer chromatography (HPTLC) method tailored for screening tyramine in cheese. Separation was performed on glass backed silica gel plates, using methanol/ethyl acetate/ammonia (6/4/1 v/v/v) as the mobile phase. Special efforts were focused on optimizing conditions (substrate preparation, laser wavelength, salt types and concentrations) of surface enhanced Raman spectroscopy (SERS) measurements directly on plates after derivatization, which enabled molecule-specific identification of targeted bands. In parallel, fluorescent densitometry (FLD) scanning at 380

Assuntos
Queijo/análise , Cromatografia em Camada Fina/métodos , Densitometria/métodos , Microscopia Óptica não Linear/métodos , Tiramina/análise , Análise de Alimentos/métodos , Sensibilidade e Especificidade
9.
Food Chem ; 232: 560-565, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490111

RESUMO

In this study, the effects of high hydrostatic pressure and retrogradation (HHPR) treatments on in vitro digestibility, structural and physicochemical properties of waxy wheat starch were investigated. The waxy wheat starch slurries (10%, w/v) were treated with high hydrostatic pressures of 300, 400, 500, 600MPa at 20°C for 30min, respectively, and then retrograded at 4°C for 4d. The results indicated that the content of slowly digestible starch (SDS) in HHPR-treated starch samples increased with increasing pressure level, and it reached the maximum (31.12%) at 600MPa. HHPR treatment decreased the gelatinization temperatures, the gelatinization enthalpy, the relative crystallinity and the peak viscosity of the starch samples. Moreover, HHPR treatment destroyed the surface and interior structures of starch granules. These results suggest that the in vitro digestibility, physicochemical, and structural properties of waxy wheat starch are effectively modified by HHPR.


Assuntos
Amido , Triticum , Amilopectina , Pressão Hidrostática , Temperatura
10.
Carbohydr Polym ; 151: 381-391, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474580

RESUMO

In this study, response surface methodology (RSM) was employed to optimize microwave-assisted extraction (MAE) technology of mucilage polysaccharide from the peel of Opuntia dillenii haw. fruits (OFPP), and the physicochemical characteristics of OFPP were also investigated. The three parameters were the ratio of water to raw material (30-40ml/g), microwave power (300-400W) and extraction time (120-180s). The results indicated that the yield of OFPP was 15.62±0.37% under the optimum extraction conditions. Compared with MAE, the OFPP yield by hot water extraction (HWE) was 13.36±0.71%. In addition, the rheological properties of OFPP were also explored. The OFPP obtained by HWE exhibited a lower viscosity compared with that by MAE. The FT-IR spectra analysis, scanning electron microscopy (SEM) observation and thermogravimetric analysis (TGA) revealed that there were strong interactions between Ca(2+) and OFPP, which resulted in the high viscosity, different microstructure and thermal stability of OFPP.


Assuntos
Fracionamento Químico/métodos , Opuntia/química , Mucilagem Vegetal/isolamento & purificação , Viscosidade , Cálcio/química , Cátions Bivalentes/química , Frutas/química , Micro-Ondas , Mucilagem Vegetal/química , Reologia
11.
Biochem J ; 473(14): 2141-54, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27208177

RESUMO

Selenophosphate synthetase (SPS) was initially detected in bacteria and was shown to synthesize selenophosphate, the active selenium donor. However, mammals have two SPS paralogues, which are designated SPS1 and SPS2. Although it is known that SPS2 catalyses the synthesis of selenophosphate, the function of SPS1 remains largely unclear. To examine the role of SPS1 in mammals, we generated a Sps1-knockout mouse and found that systemic SPS1 deficiency led to embryos that were clearly underdeveloped by embryonic day (E)8.5 and virtually resorbed by E14.5. The knockout of Sps1 in the liver preserved viability, but significantly affected the expression of a large number of mRNAs involved in cancer, embryonic development and the glutathione system. Particularly notable was the extreme deficiency of glutaredoxin 1 (GLRX1) and glutathione transferase Omega 1 (GSTO1). To assess these phenotypes at the cellular level, we targeted the removal of SPS1 in F9 cells, a mouse embryonal carcinoma (EC) cell line, which affected the glutathione system proteins and accordingly led to the accumulation of hydrogen peroxide in the cell. Furthermore, we found that several malignant characteristics of SPS1-deficient F9 cells were reversed, suggesting that SPS1 played a role in supporting and/or sustaining cancer. In addition, the overexpression of mouse or human GLRX1 led to a reversal of observed increases in reactive oxygen species (ROS) in the F9 SPS1/GLRX1-deficient cells and resulted in levels that were similar to those in F9 SPS1-sufficient cells. The results suggested that SPS1 is an essential mammalian enzyme with roles in regulating redox homoeostasis and controlling cell growth.


Assuntos
Fosfotransferases/metabolismo , Animais , Linhagem Celular , Glutarredoxinas/genética , Glutarredoxinas/metabolismo , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Homeostase/genética , Homeostase/fisiologia , Humanos , Fígado/metabolismo , Camundongos , Camundongos Knockout , Oxirredução , Fosfotransferases/genética , Fosfato de Piridoxal/metabolismo
12.
PLoS One ; 10(6): e0127349, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26043259

RESUMO

Selenocysteine tRNA 1 associated protein (Trnau1ap) has been characterized as a tRNA[Ser]Sec-binding protein of 43 kDa, hence initially named SECp43. Previous studies reported its presence in complexes containing tRNA[Ser]Sec implying a role of SECp43 as a co-factor in selenoprotein expression. We generated two conditionally mutant mouse models targeting exons 3+4 and exons 7+8 eliminating parts of the first RNA recognition motif or of the tyrosine-rich domain, respectively. Constitutive inactivation of exons 3+4 of SECp43 apparently did not affect the mice or selenoprotein expression in several organs. Constitutive deletion of exons 7+8 was embryonic lethal. We therefore generated hepatocyte-specific Secp43 knockout mice and characterized selenoprotein expression in livers of mutant mice. We found no significant changes in the levels of 75Se-labelled hepatic proteins, selenoprotein levels as determined by Western blot analysis, enzymatic activity or selenoprotein mRNA abundance. The methylation pattern of tRNA[Ser]Sec remained unchanged. Truncated Secp43 Δ7,8mRNA increased in Secp43-mutant livers suggesting auto-regulation of Secp43 mRNA abundance. We found no signs of liver damage in Secp433-mutant mice, but neuron-specific deletion of exons 7+8 impaired motor performance, while not affecting cerebral selenoprotein expression or cerebellar development. These findings suggest that the targeted domains in the SECp43 protein are not essential for selenoprotein biosynthesis in hepatocytes and neurons. Whether the remaining second RNA recognition motif plays a role in selenoprotein biosynthesis and which other cellular process depends on SECp43 remains to be determined.


Assuntos
Regulação da Expressão Gênica , Hepatócitos/metabolismo , Fígado/metabolismo , Neurônios/metabolismo , Proteínas de Ligação a RNA/metabolismo , Selenoproteínas/biossíntese , Motivos de Aminoácidos , Animais , Éxons , Camundongos , Camundongos Mutantes , Especificidade de Órgãos/genética , Proteínas de Ligação a RNA/genética , Selenoproteínas/genética
13.
Food Chem ; 187: 218-24, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25977019

RESUMO

The effects of debranching treatment (DT) and debranching-heat-moisture treatment (D-HMT) on the structural characteristics and in vitro digestibility of sweet potato starch were investigated. The results indicated that DT and D-HMT decreased the percentage of starch fraction with degree of polymerization (DP) ⩽ 13, increased the percentages of the other fractions, and decreased the molecular weight of starch sample. The D-HMT starch showed a considerable SDS content of 31.60%. Compared with the DT starch sample, the T(o), T(p), T(c), T(c)-T(o) and ΔH of D-HMT starch samples for the second endothermal were increased significantly, crystalline pattern was altered from C(a) to A type, the surface became more smooth. The pasting temperatures of DT and D-HMT starch samples were higher while the peak viscosities, breakdown and setback values were lower than that of native starch. These results suggested that structural changes of sweet potato starch by D-HMT significantly affected the digestibility.


Assuntos
Ipomoea batatas/metabolismo , Amido/química , Configuração de Carboidratos , Digestão , Temperatura Alta , Humanos , Ipomoea batatas/química , Amido/metabolismo , Viscosidade
14.
Food Chem ; 187: 378-84, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25977040

RESUMO

In this study, citric acid was used to react with cassava starch in order to compare the digestibility, structural and physicochemical properties of citrate starch samples. The results indicated that citric acid esterification treatment significantly increased the content of resistant starch (RS) in starch samples. The swelling power and solubility of citrate starch samples were lower than those of native starch. Compared with native starch, a new peak at 1724 cm(-1) was appeared in all citrate starch samples, and crystalline peaks of all starch citrates became much smaller or even disappeared. Differential scanning calorimetry results indicated that the endothermic peak of citrate starches gradually shrank or even disappeared. Moreover, the citrate starch gels exhibited better freeze-thaw stability. These results suggested that citric acid esterification induced structural changes in cassava starch significantly affected its digestibility and it could be a potential method for the preparation of RS with thermal stability.


Assuntos
Ácido Cítrico/química , Manihot/química , Amido/química , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Esterificação , Géis/química , Solubilidade
15.
PLoS One ; 10(4): e0124487, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25886253

RESUMO

Selenoproteins mediate much of the cancer-preventive properties of the essential nutrient selenium, but some of these proteins have been shown to also have cancer-promoting effects. We examined the contributions of the 15kDa selenoprotein (Sep15) and thioredoxin reductase 1 (TR1) to cancer development. Targeted down-regulation of either gene inhibited anchorage-dependent and anchorage-independent growth and formation of experimental metastases of mouse colon carcinoma CT26 cells. Surprisingly, combined deficiency of Sep15 and TR1 reversed the anti-cancer effects observed with down-regulation of each single gene. We found that inflammation-related genes regulated by Stat-1, especially interferon-γ-regulated guanylate-binding proteins, were highly elevated in Sep15-deficient, but not in TR1-deficient cells. Interestingly, components of the Wnt/ß-catenin signaling pathway were up-regulated in cells lacking both TR1 and Sep15. These results suggest that Sep15 and TR1 participate in interfering regulatory pathways in colon cancer cells. Considering the variable expression levels of Sep15 and TR1 found within the human population, our results provide insights into new roles of selenoproteins in cancer.


Assuntos
Neoplasias do Colo/patologia , Selenoproteínas/metabolismo , Tiorredoxina Redutase 1/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/enzimologia , Neoplasias do Colo/metabolismo , Perfilação da Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Selenoproteínas/genética , Tiorredoxina Redutase 1/genética
16.
Carbohydr Polym ; 124: 25-34, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-25839790

RESUMO

In this study, a novel water-soluble polysaccharide fraction with molecular weight of 6479.1kDa was isolated from the fruits of Opuntia dillenii Haw., which consisted of rhamnose, xylose, mannose and glucose in the molar ratio of 14.99:1.14:1.00:6.47. The protective effect of O. dillenii Haw. fruits polysaccharide (ODFP) against oxidative damage in streptozotocin (STZ)-induced diabetic rats was investigated. The results showed that oral administration of ODFP significantly decreased food intake, water intake, urine production, organ weights and blood glucose level, and increased body weight in STZ-induced diabetic rats. ODFP also significantly increased the activities of SOD, GPx and CAT, and decreased malondialdehyde level in serum, liver, kidney, and pancreas in STZ-induced diabetic rats. Moreover, histopathological examination showed that ODFP could markedly improve the structure integrity of pancreatic islet tissue in STZ-induced diabetic rats. These results suggest that ODFP have hypoglycemic and antioxidant properties and can protect rats from STZ-induced oxidative damage.


Assuntos
Antioxidantes/uso terapêutico , Diabetes Mellitus Experimental/prevenção & controle , Hipoglicemiantes/uso terapêutico , Ilhotas Pancreáticas/efeitos dos fármacos , Polissacarídeos/uso terapêutico , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Frutas/química , Ilhotas Pancreáticas/patologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Opuntia/química , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Ratos
17.
Food Chem ; 169: 430-8, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25236248

RESUMO

A novel polysaccharide fraction (LP2-1) was isolated and purified from the edible bulbs of Lilium lancifolium Thunb. by DEAE cellulose chromatography and Sephacryl S-400 size-exclusion chromatography. The structural characterisation, physicochemical properties and antioxidant activity of LP2-1 were investigated. The results showed that LP2-1 had an average molecular weight of approximately 8.52×10(3)kDa and was mainly composed of l-rhamnopyranose, d-arabinofuranose, d-glucopyranose and d-galactopyranose in the molar ratio of 1.88:2.13:1.00:2.50, and major functional groups of LP2-1 were COO and OH. The viscoelastic properties of LP2-1 systems exhibited a gel-like behaviour, with storage modulus higher than loss modulus, and both moduli increased with increasing Ca(2+) concentration. In addition, LP2-1 had DPPH and hydroxyl radicals scavenging activities, and also had the strong reducing power and chelating activity on ferrous ion. These results suggest that LP2-1 has good antioxidant activity and can be used in food industry.


Assuntos
Antioxidantes/farmacologia , Lilium/química , Polissacarídeos/farmacologia , Cromatografia em Gel , Espectroscopia de Ressonância Magnética , Polissacarídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Urônicos/análise
18.
Food Chem ; 174: 31-6, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529648

RESUMO

The effects of continuous retrogradation (CR) and intermittent retrogradation (IR) treatments under 4 °C and 25 °C or temperature-cycled condition of 4/25 °C on the digestibility and structural properties of waxy wheat starch were investigated. The results indicated that IR treatment under temperature cycles of 4/25 °C (IR-4/25) was more beneficial to the formation of slowly digestible starch (SDS, 42.24%). Moreover, the gelatinisation enthalpy of IR-4/25-treated starch sample was lower than that of CR-4/25-treated sample. Variation in infrared absorbance ratio of 1047 cm(-1)/1022 cm(-1) of IR-treated starch samples was consistent with relative crystallinity. Through retrogradation treatment under 4/25 °C or 4 °C, starch samples exhibited X-ray diffraction pattern of B-type, while CR-25 and IR-25-treated samples showed a mixed A+B type pattern. Besides, the swelling power of CR-4/25-treated starch sample was higher than that of IR-4/25-treated sample. The pasting temperatures of IR-treated starch samples were higher than those of the CR-treated samples.


Assuntos
Amido/química , Triticum/química , Digestão , Temperatura , Termodinâmica , Difração de Raios X
19.
Food Chem ; 163: 219-25, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24912719

RESUMO

The effects of repeated retrogradation (RR) treatment on the structural characteristics and in vitro digestibility of waxy potato starch were investigated. The cycling times of RR ranging from 1 to 5 were designated as RR-1, RR-2, RR-3, RR-4, and RR-5, respectively. A maximum SDS content (40.41%) was obtained by RR-2 treatment with the time interval of 48h. RR-2-treated starch product exhibited a narrower melting temperature range, a higher onset temperature and a lower melting enthalpy compared with RR-1 treatment. Compared with native starch, X-ray diffraction patterns of treated starches were altered from B-type to C-type. The variation in relative crystallinity of RR-treated starch products was consistent with that in melting enthalpy. Moreover, compared with RR-1-treated starch, a large number of cavities were observed on the surface of RR-2-treated starch product with a time interval of 48h, whereas more smooth regions were found on the surface of RR-5-treated starch product. This study suggested that structural changes of waxy potato starch treated with different cycling times of RR significantly affected the digestibility.


Assuntos
Digestão , Solanum tuberosum/metabolismo , Amido/química , Humanos , Modelos Biológicos , Solanum tuberosum/química , Amido/metabolismo , Termodinâmica , Difração de Raios X
20.
Food Chem ; 157: 373-9, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24679793

RESUMO

The effects of single-retrogradation (SR), dual-retrogradation (DR) and triple-retrogradation (TR) treatments on in vitro digestibility and structural characteristics of waxy wheat starch were investigated. The yield of slowly digestible starch in a DR-treated starch with retrogradation time interval of 48 h reached a maximum of 44.41%. The gelatinization temperature range and gelatinization enthalpy of DR-treated starch samples were the lowest. Moreover, compared with native starch, X-ray diffraction patterns of treated starches were altered from A-type to B-type and relative crystallinity was significantly decreased, which was responsible for the interaction between amylose-amylose and/or amylose-amylopectin chains that may generate more imperfect structures. Scanning electron micrographs revealed that compared with SR-treated and TR-treated starches, the surface of DR-treated starch with a retrogradation time interval of 48 h exhibited a net-like structure with numerous cavities. These results suggest that structural changes of waxy wheat starch by cycled retrogradation treatment significantly affect digestibility, and DR treatment can be used for preparing SDS product.


Assuntos
Amilose/química , Varredura Diferencial de Calorimetria/métodos , Amido/química , Triticum/química , Amilopectina/química , Técnicas In Vitro , Termodinâmica
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