High dietary wheat starch negatively regulated growth performance, glucose and lipid metabolisms, liver and intestinal health of juvenile largemouth bass, Micropterus salmoides.

Largemouth bass (Micropterus salmoides) were fed with three diets containing 6%, 12%, and 18% wheat starch for 70 days to examine their impacts on growth performance, glucose and lipid metabolisms, and liver and intestinal health. The results suggested that the 18% starch group inhibited the growth, and improved the hepatic glycogen content compared with the 6% and 12% starch groups (P < 0.05). High starch significantly improved the activities of glycolysis-related enzymes, hexokinase (HK), glucokinase (GK), phosphofructokinase (PFK), and pyruvate kinase (PK) (P < 0.05); promoted the mRNA expression of glycolysis-related phosphofructokinase (pfk); decreased the activities of gluconeogenesis-related enzymes, pyruvate carboxylase (PC), and phosphoenolpyruvate carboxykinase (PEPCK); and reduced the mRNA expression of gluconeogenesis-related fructose-1,6-bisphosphatase-1(fbp1) (P < 0.05). High starch reduced the hepatic mRNA expressions of bile acid metabolism-related cholesterol hydroxylase (cyp7a1) and small heterodimer partner (shp) (P < 0.05), increased the activity of hepatic fatty acid synthase (FAS) (P < 0.05), and reduced the hepatic mRNA expressions of lipid metabolism-related peroxisome proliferator-activated receptor α (ppar-α) and carnitine palmitoyltransferase 1α (cpt-1α) (P < 0.05). High starch promoted inflammation; significantly reduced the mRNA expressions of anti-inflammatory cytokines transforming growth factor-ß1 (tgf-ß1), interleukin-10 (il-10), and interleukin-11ß (il-11ß); and increased the mRNA expressions of pro-inflammatory cytokine tumor necrosis factor-α (tnf-α), interleukin-1ß (il-1ß), and interleukin-8 (il-8) in the liver and intestinal tract (P < 0.05). Additionally, high starch negatively influenced the intestinal microbiota, with the reduced relative abundance of Trichotes and Actinobacteria and the increased relative abundance of Firmicutes and Proteobacteria. In conclusion, low dietary wheat starch level (6%) was more profitable to the growth and health of M. salmoides, while high dietary starch level (12% and 18%) could regulate the glucose and lipid metabolisms, impair the liver and intestinal health, and thus decrease the growth performance of M. salmoides.

Thermal, Rheological, Structural and Adhesive Properties of Wheat Starch Gels with Different Potassium Alum Contents.

Wheat starch (WS) is a common adhesive material used in mounting of calligraphy and paintings. Potassium alum (PA) has indeed been used for many centuries to modify the physicochemical properties of starch. Thermal analysis revealed that the presence of PA led to an increase in the gelatinization temperature and enthalpy of the starch gels. The leached amylose and the swelling power of the starch gels exhibited a maximum at the ratio of 100:6.0 (WS:PA, w/w). The rheological properties of starch gels were consistent with changes in the swelling power of starch granules. SEM observations confirmed that the gel structure became more regular, and the holes grew larger with the addition of PA below the ratio of 100:6.0 (WS:PA, w/w). The short-range molecular order in the starch gels was enhanced by the addition of PA, confirmed by FT-IR analysis. Mechanical experiments demonstrated that the binding strength of the starch gels increased with higher PA concentrations and decreased significantly after the aging process. TGA results revealed that PA promoted the acid degradation of starch molecules. This study provides a detailed guide for the preparation of starch-based adhesive and its applications in paper conservation.

Influence of damaged starch on thermal and rheological properties of wheat starch and wheat starch-gluten systems in water and sucrose.

BACKGROUND: The granular integrity of starch granules is affected by the mechanical action of the milling-process, thus producing what is called damaged starch (DS). The effect of DS on bakery products was extensively studied, but there is not much information about the effect of this minor flour component on batter-type products in which there is a high amount of sucrose. The objective of this work was to study the influence of damaged wheat-starch on starch and starch-gluten systems dispersed in water and sucrose 500 g kg-1 solution. RESULTS: Thermal and pasting properties and the viscoelastic behavior of the systems were evaluated. Gelatinization enthalpy decreased when DS amount increased in the samples in both solvents. In starch-gluten systems, the degree of influence of DS on the gelatinization enthalpy was solvent-dependent. The presence of gluten minimized the effect of DS on the gelatinization process in water. The viscosity profile of starch and starch-gluten samples was reduced in both solvents when DS level increased. The influence of DS on the viscosity profile was solvent-dependent in starch-gluten systems. The presence of gluten lessened the influence of DS on the viscosity profile during the pasting process in sucrose solution. Higher DS levels decreased the viscoelastic behavior of the systems in both solvents and further reduced the viscoelastic behavior of the systems in sucrose solution. CONCLUSION: These results contribute to understanding the influence of the DS levels on the batter properties of flour-based batter-type products, mainly those generated on starch and gluten-starch systems dispersed in sucrose solution. © 2022 Society of Chemical Industry.

Impact of flavonol extracts derived from green tea or targeted flavonols as secondary ingredients on intestinal glucose transport.

The purpose of the current study was to examine the effect of adding secondary ingredients such as green tea derived water-soluble polysaccharides (GTP) and flavonol aglycone rich fractions derived from cellulase treated green tea extract (FVN) into catechin rich green tea extracts (GTE) on wheat starch digestion and intestinal glucose transport using in vitro digestion with Caco-2 cells. Co-digestion of wheat starch with GTE (16.88 g L-1) or GTE + GTP + FVN (16.69 g L-1) appeared to promote starch hydrolysis compared to control (15.49 g L-1). In case of major flavonoids, addition of epigallocatechin gallate (EGCG), EGCG + myricetin (M) into wheat starch significantly increased the digestion of starch into glucose. Glucose transport rate decreased by 22.35% in wheat starch + GTE + GTP + FVN (1.39%), while the least amount of glucose (1.70%) was transported in EGCG mixed with M (1% of EGCG) as secondary ingredients among individual flavonoids formulation. It indicated that inhibitory effect on glucose transport was higher in addition of GTE, GTP, and FVN as excipients ingredients rather than targeted major flavonoids. Results from the current study suggest that whole green tea including flavonoid rich fractions could enhance hypoglycemic potential of GTE. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05140-2.

Application of high-pressure homogenization to tailor the functionalities of native wheat starch.

BACKGROUND: The effect of high-pressure homogenization (HPH) on the rheological and thermal properties, water retention capacity (WRC), morphology and in vitro digestion of wheat starch was evaluated. Starch suspensions (50 g kg-1 , w/w) were treated at increasing pressures (up to 100 MPa) and numbers of cycles (up to 5) to generate a wide range of energy densities (70-500 MJ m-3 ) delivered to the sample during processing. RESULTS: High-pressure homogenization induced a partial starch gelatinization confirmed by higher digestibility. Gelatinization degree (GD) was between 13% and 83%, causing a wide range of functional properties. High-pressure homogenization-treated starch samples showed WRC values of 810-1910 g kg-1 . Storage modulus (G') and complex viscosity (η* ) of starch dispersions were almost two and three times higher than the control at 13% and 83% GD, respectively. Positive linear relationships between GD (R = 0.98, P < 0.001), WRC (R = 0.87, P < 0.05), or rheological parameters (R = 0.89÷0.90, P < 0.01) and energy density of HPH treatments were found. CONCLUSION: High-pressure homogenization treatment represents a promising technology to obtain wheat starch with tailored rheological properties and digestibility, which allows the texture and glycemic response of food products to be adjusted. © 2020 Society of Chemical Industry.

Polysaccharide-Based Injection Matrix for Serial Crystallography.

Serial crystallography (SX) provides an opportunity to observe the molecular dynamics of macromolecular structures at room temperature via pump-probe studies. The delivery of crystals embedded in a viscous medium via an injector or syringe is widely performed in synchrotrons or X-ray free-electron laser facilities with low repetition rates. Various viscous media have been developed; however, there are cases in which the delivery material undesirably interacts chemically or biologically with specific protein samples, or changes the stability of the injection stream, depending on the crystallization solution. Therefore, continued discovery and characterization of new delivery media is necessary for expanding future SX applications. Here, the preparation and characterization of new polysaccharide (wheat starch (WS) and alginate)-based sample delivery media are introduced for SX. Crystals embedded in a WS or alginate injection medium showed a stable injection stream at a flow rate of < 200 nL/min and low-level X-ray background scattering similar to other hydrogels. Using these media, serial millisecond crystallography (SMX) was performed, and the room temperature crystal structures of glucose isomerase and lysozyme were determined at 1.9-2.0 Å resolutions. WS and alginate will allow an expanded application of sample delivery media in SX experiments.

Suitability and Modification of Different Renewable Materials as Feedstock for Sustainable Flame Retardants.

Due to their chemical structure, conventional flame retardants are often toxic, barely biodegradable and consequently neither healthy nor environmentally friendly. Their use is therefore increasingly limited by regulations. For this reason, research on innovative flame retardants based on sustainable materials is the main focus of this work. Wheat starch, wheat protein, xylan and tannin were modified with phosphate salts in molten urea. The functionalization leads to the incorporation of phosphates (up to 48 wt.%) and nitrogen (up to 22 wt.%). The derivatives were applied on wood fibers and tested as flame retardants. The results indicate that these modified biopolymers can provide the same flame-retardant performances as commercial compounds currently used in the wood fiber industry. Besides, the flame retardancy smoldering effects may also be reduced compared to unmodified wood fibers depending on the used biopolymer. These results show that different biopolymers modified in phosphate/urea systems are a serious alternative to conventional flame retardants.

Hypoglycemic effect of soluble polysaccharide and catechins from green tea on inhibiting intestinal transport of glucose.

BACKGROUND: Water soluble polysaccharide derived from green tea (WSP) is produced as byproducts when catechins were extracted from green tea. Although inhibitory effect of green tea catechins on the glucose transport in small intestine has been studied, the hypoglycemic efficacy of the WSP or its combinational effect has not been studied. In order to investigate hypoglycemic efficacy of the WSP or its combinational effect with green tea extract (GTE), co-consumption of GTE and WSP with wheat starch was investigated using in vitro digestion coupled with Caco-2 cells. The mechanism of the intestinal glucose transport was elucidated throughout the gene expression of the intestinal glucose transporters, which included sodium dependent glucose transporter (SGLT1) and glucose transporter 2 (GLUT2), using quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: The co-digestion of wheat starch with GTE during the small intestinal phase was the most rapidly digested into reducing sugar (73.96 g L-1 ) compared to itself (48.44 g L-1 ), WSP (60.35 g L-1 ), and GTE + WSP (61.81 g L-1 ). Intestinal glucose transport was 11.82, 7.59, 4.49, and 2.40% for wheat starch, wheat starch with GTE, WSP, and GTE + WSP, respectively. The highest decreased expression pattern in SGLT1 was observed when cells treated with wheat starch + GTE + WSP (0.66-fold) compared to GTE or WSP treatment. CONCLUSION: The results suggested that co-consumption of green tea derived products with wheat starch could delay the intestinal absorption of glucose. Results from the current study suggested that GTE and WSP could be the useful supplements of dietary therapy for hyperglycemia to delay glucose absorption. © 2020 Society of Chemical Industry.

Identification of Differentially Expressed Micrornas Associate with Glucose Metabolism in Different Organs of Blunt Snout Bream (Megalobrama amblycephala).

Blunt snout bream (Megalobrama amblycephala) is a widely favored herbivorous fish species and is a frequentlyused fish model for studying the metabolism physiology. This study aimed to provide a comprehensive illustration of the mechanisms of a high-starch diet (HSD) induced lipid metabolic disorder by identifying microRNAs (miRNAs) controlled pathways in glucose and lipid metabolism in fish using high-throughput sequencing technologies. Small RNA libraries derived from intestines, livers, and brains of HSD and normal-starch diet (NSD) treated M. amblycephala were sequenced and 79, 124 and 77 differentially expressed miRNAs (DEMs) in intestines, livers, and brains of HSD treated fish were identified, respectively. Bioinformatics analyses showed that these DEMs targeted hundreds of predicted genes were enriched into metabolic pathways and biosynthetic processes, including peroxisome proliferator-activated receptor (PPAR), glycolysis/gluconeogenesis, and insulin signaling pathway. These analyses confirmed that miRNAs play crucial roles in glucose and lipid metabolism related to high wheat starch treatment. These results provide information on further investigation of a DEM-related mechanism dysregulated by a high carbohydrate diet.

Formation of macromolecules in wheat gluten/starch mixtures during twin-screw extrusion: effect of different additives.

BACKGROUND: Wheat gluten comprises a good quality and inexpensive vegetable protein with an ideal amino acid composition. To expand the potential application of wheat gluten in the food industry, the effect of different additives on the physicochemical and structural properties of wheat gluten/starch mixtures during twin-screw extrusion was investigated. RESULTS: Macromolecules were observed to form in wheat gluten/starch mixtures during twin-screw extrusion, which may be attributed to the formation of new disulfide bonds and non-covalent interactions, as well as Maillard reaction products. Additionally, the water retention capacity and in vitro protein digestibility of all extruded wheat gluten/starch products significantly increased, whereas the nitrogen solubility index and free sulfhydryl group (SH) content decreased, during twin-screw extrusion. Secondary structural analysis showed that α-helices disappeared with the concomitant increase of antiparallel ß-sheets, demonstrating the occurrence of protein aggregation. Microstructures suggested that the irregular wheat gluten granular structure was disrupted, with additive addition favoring transformation into a more layered or fibrous structure during twin-screw extrusion. CONCLUSION: The findings of the present study demonstrate that extrusion might affect the texture and quality of extruded wheat gluten-based foods and suggest that this process might serve as a basis for the high-value application of wheat gluten products. © 2017 Society of Chemical Industry.

Effects of carbohydrate/protein ratio on the microstructure and the barrier and sorption properties of wheat starch-whey protein blend edible films.

BACKGROUND: Starch and whey protein isolate and their mixtures were used for making edible films. Moisture sorption isotherms, water vapour permeability, sorption of aroma compounds, microstructure, water contact angle and surface properties were investigated. RESULTS: With increasing protein content, the microstructure changes became more homogeneous. The water vapour permeability increases with both the humidity gradient and the starch content. For all films, the hygroscopicity increases with starch content. Surface properties change according to the starch/whey protein ratio and are mainly related to the polar component of the surface tension. Films composed of 80% starch and 20% whey proteins have more hydrophobic surfaces than the other films due to specific interactions. CONCLUSIONS: The effect of carbohydrate/protein ratio significantly influences the microstructure, the surface wettability and the barrier properties of wheat starch-whey protein blend films. © 2016 Society of Chemical Industry.

Multilevel Structure of Wheat Starch and Its Relationship to Noodle Eating Qualities.

Although the processing and eating qualities of noodles are largely related to the quality and quantity of wheat protein (gluten), the importance of starch, a major ingredient of wheat flour, is often overlooked. Recent developments on the multilevel structural model of starch have brought new insights into the role of starch for better processing and noodle eating qualities. With critical analysis and discussion, this review outlines the comprehensive relationships between the multilevel (molecular, crystalline, and granular) starch structure, noodle eating qualities, and related physicochemical properties. Further, the major and minor structural features of wheat starch and their contributions toward noodle quality are summarized and presented as a schematic diagram, which shows the effects of starch structure on cooked noodles. These features provide new insights for the scientific community, as well as industry, into the role of starch, along with gluten, on the quality of noodles.

Thermal, pasting and morphological properties of starch granules of wheat (Triticum aestivum L.) varieties.

Large (A) and small (B) granules of wheat starch were separated and their morphological, thermal, structural and pasting properties were investigated. The pasting properties of starches from two wheat varieties showed significant differences. For wheat variety C-306, the unfractionated starch showed higher peak, trough, breakdown, final, and setback viscosities than the starch isolated from wheat variety WH-147. On the contrary, unfractionated starch of variety WH-147 has higher pasting temperature than the starch of the variety C-306. Differential scanning calorimetry results showed that unfractionated starch exhibited the higher gelatinization enthalpy, peak and conclusion temperatures than the isolated A- and B-starch granules from both the varieties. Scanning electron microscopy results revealed that large A-granules appeared to be smooth and displayed disk or lenticular shape having diameter 13-35 µm, while B-granules showed a spherical shape with diameter of 2-6 µm. The variations in structures and content would result in starch granules with different chemical and physical properties.

Mixture design of rice flour, maize starch and wheat starch for optimization of gluten free bread quality.

Gluten-free bread production requires gluten-free flours or starches. Rice flour and maize starch are two of the most commonly used raw materials. Over recent years, gluten-free wheat starch is available on the market. The aim of this research was to optimize mixtures of rice flour, maize starch and wheat starch using an experimental mixture design. For this purpose, dough rheology and its fermentation behaviour were studied. Quality bread parameters such as specific volume, texture, cell structure, colour and acceptability were also analysed. Generally, starch incorporation reduced G* and increased the bread specific volume and cell density, but the breads obtained were paler than the rice flour breads. Comparing the starches, wheat starch breads had better overall acceptability and had a greater volume than maize-starch bread. The highest value for sensorial acceptability corresponded to the bread produced with a mixture of rice flour (59 g/100 g) and wheat starch (41 g/100 g).

Functional properties of wheat starch with different particle size distribution.

BACKGROUND: Functional properties of wheat starches with different particle size distribution were investigated. RESULTS: A-granules displayed a disc shape and B-granules displayed a spherical shape. A-granules had the highest conclusion temperature (Tc , 80.28 °C) and gelatinisation enthalpy (3.268 J g(-1)) and B-granules had the highest peak temperature (Tp, 66.00 °C) and the lowest gelatinisation enthalpy (2.237 J g(-1)). The gelatinisation onset temperature (To), the peak temperature (Tp), Tc and retrogradation of mixed starches increased with the increase of the ratio of B-granules, while the enthalpy, all the viscosity parameters and syneresis of mixed starches decreased with the increase of the ratio of B granules. B-granules had a higher pasting temperature. The sample of B/A = 0.5/10 had the highest peak, breakdown and final viscosity. The percentage of water separated from B-granule gels was minimal, indicated that B-type gels were more stable than other samples. The ΔH2 of A-granules was obviously higher than that of B-granules. However, during storage, the ΔH2 of the starch paste was dramatically increased and the ΔH2 of B-granules was obviously higher than that of A-granules. CONCLUSION: B-granules were easier to age than A-granules and most of the properties of wheat starches varied significantly with the ratio of B-granules. The relationship between structure and functionality of wheat starch received further verification.

Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

Modification of wheat starch with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures. II. Chemical and physical properties.

The aim of this research was to investigate the influence of modification with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures on chemical and physical properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetanhydride and azelaic acid and acetanhydride in 4, 6 and 8% (w/w). Total starch content, resistant starch content, degree of modification, changes in FT-IR spectra, colour, gel texture and freeze-thaw stability were determined. Results showed that resistant starch content increased by both investigated modifications, and degree of modification increased proportionally to amount of reagents used. FT-IR analysis of modified starches showed peak around 1,740 cm(-1), characteristic for carbonyl group of ester. Total colour difference caused by modifications was detectable by trained people. Adhesiveness significantly increased, while freeze-thaw stability decreased by both investigated modifications.

A study of the low-protein diet in delaying the course of chronic kidney disease.

A low-protein diet (LPD) has become an important way to delay the progression of chronic kidney disease (CKD) and to delay the need for dialysis. A review of the literature reveals the low-protein diet's influence on the course of chronic kidney disease. An artificial low-protein food, wheat starch, for example, can not only increase the high-quality protein intake ratio, but can ensure adequate energy intake on a low-protein diet while meeting the nutritional needs of the body, effectively reducing the burden on the damaged kidneys. The purpose of this review is to provide a reference for the clinical implementation of diet and nutrition therapy in patients with chronic kidney disease.

A- and B-type wheat starch granules: The multiscale structural evolution during digestion and the distinct digestion mechanisms.

The digestive characteristics of wheat starch are closely related to human health. However, the digestive mechanisms of distinct wheat starch granules are not well understood. To address this problem, A- and B-type wheat starch granules (AWS and BWS, respectively) were digested in vitro and the structural evolution of the digestive remnants was compared. After stomach-intestinal digestion of AWS, its crystallinity decreased from 12.75 % to 6.65 %, its fractal dimension decreased from 3.12 to 2.35, and the median particle size decreased from 20.613 to 10.135 µm. Additionally, the number of short chains (polymerization degree<14) and thermodynamic stability decreased after digestion. For BWS, Fourier transform infrared ratio of 1047/1022 cm-1 and 995/1022 cm-1 increased from 0.665 and 0.725 to 0.990 and 0.800, respectively. The median particle size decreased from 5.480 to 4.769 µm. An enzyme-resistant scattering peak was observed in the 1.35 nm-1 lamellar structure. Additionally, the number of B2 and B3 chains and the thermodynamic stability increased after digestion. Our study confirmed that BWS is more likely than AWS to form enzyme-resistant structures during digestion. These findings provide insights into the distinct digestion mechanisms of AWS and BWS, and serve as a foundation for modifying wheat starch to increase its nutritional value.

Effects of heat-moisture treatment on structural characteristics and in vitro digestibility of A- and B-type wheat starch.

In this study, A- and B-type wheat starch granules (AWS and BWS) were separated and modified by heat-moisture treatment (HMT) with different moisture content (10 %-40 %). The effects of HMT on the structure characteristics and digestibility of raw/cooked AWS and BWS were investigated by SEM, FT-IR, XRD, DSC, TGA and NMR. SEM and FT-IR results showed that BWS was more sensitive to HMT than AWS. Interestingly, crystalline conformation of AWS and BWS changed from A type to A + V type after HMT, and the relative crystallinity (V-type) of starch increased to 2.7 % and 3.4 %, respectively. XRD and NMR results verified the formation of V-type crystalline structure. The resistant starch (RS) content of cooked starch was increased, especially for BWS (from 11.46 % to 28.29 %). Compared to the cooked starch, the RS content of raw AWS and BWS was affected by relative crystallinity and the size of starch granules. Furthermore, structure characteristics and digestion kinetics results indicated that the digestion rate of cooked AWS increased due to the deconstruction of starch chains, opposite to BWS (because of the more V-type crystals). The results enrich our understanding of the mechanism of digestion subjected to HMT by different grain sizes of the same wheat starch.