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1.
Food Res Int ; 182: 114178, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519192

RESUMO

To explore the feasibility of substituting waxy rice with waxy or sweet-waxy corn, eight varieties of waxy and sweet-waxy corns were selected, including three self-cultivated varieties (Feng nuo 168, Feng nuo 211, and Feng nuo 10). Their starches were isolated and used as research objects, and commercially available waxy rice starch (CAWR) and waxy corn starch (CAWC) were used as controls. X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, rapid viscosity analyzer, and rotational rheometer were used to analyze their physicochemical and structural characteristics. The morphologies of all corn starch granules were generally oval or round, with significant differences in particle size distributions. All ten starches exhibited a typical A-type crystal structure; however, their relative crystallinity varied from 20.08% to 31.43%. Chain length distribution analysis showed that the A/B ratio of Jing cai tian nuo 18 and Feng nuo 168 was similar to that of CAWR. Peak viscosities of corn starches were higher than that of CAWR, except for Feng nuo 10, while their setback values were lower than that of CAWR. Except for Feng nuo 10, the paste transparency of corn starches was higher than that of CAWR (10.77%), especially for Jing cai tian nuo 18 (up to 24%). In summary, Jing cai tian nuo 18 and Feng nuo 168 are promising candidates to replace CAWR in developing various rice-based products.


Assuntos
Oryza , Zea mays , Zea mays/química , Oryza/química , Ceras/química , Estudos de Viabilidade , Amido/química , Amilopectina/química
2.
Sci Rep ; 14(1): 6743, 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509120

RESUMO

In rice, grain filling is a crucial stage where asynchronous filling of the pollinated spikelet's of the panicle occurs. It can influence both grain quality and yield. In rice grain, starch is the dominant component and contains amylose and amylopectin. Amylose content is the chief cooking quality parameter, however, rice varieties having similar amylose content varied in other parameters. Hence, in this study, a set of varieties varying in yield (04) and another set (12) of varieties that are similar in amylose content with variation in gel consistency and alkali spreading value were used. Panicles were collected at various intervals and analysed for individual grain weight and quantities of amylose and amylopectin. Gas exchange parameters were measured in varieties varying in yield. Upper branches of the panicles were collected from rice varieties having similar amylose content and were subjected to gene expression analysis with fourteen gene specific primers of starch synthesis. Results indicate that grain filling was initiated simultaneously in multiple branches. Amylose and amylopectin quantities increased with the increase in individual grain weight. However, the pattern of regression lines of amylose and amylopectin percentages with increase in individual grain weight varied among the varieties. Gas exchange parameters like photosynthetic rate, stomatal conductance, intercellular CO2 and transpiration rate decreased with the increase in grain filling period in both good and poor yielding varieties. However, they decreased more in poor yielders. Expression of fourteen genes varied among the varieties and absence of SBE2b can be responsible for medium or soft gel consistency.


Assuntos
Amilose , Oryza , Amilose/metabolismo , Amilopectina/metabolismo , Amido/metabolismo , Grão Comestível/metabolismo , Oryza/genética , Oryza/metabolismo , Expressão Gênica
3.
Int J Biol Macromol ; 261(Pt 2): 129918, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309388

RESUMO

This study examined four types of japonica rice from Yangtze River Delta, categorized based on amylose content (AC) and protein content (PC): high AC with high PC, high AC with low PC, low AC with high PC, and low AC with low PC. It systematically explored the effect of starch, protein and their interactions on eating quality of japonica rice. Rheological analysis revealed that increased amylose, long chains amylopectin or protein levels during cooking strengthen starch-protein interactions (hydrogen bonding), forming a firm gel network. Scanning electron microscopy showed that increased amylose, long chains amylopectin or protein levels made protein and starch more stable in combination during cooking, limiting starch structure cleavage. Therefore, the eating quality of high AC in similar PC japonica rice and high PC in similar AC japonica rice were poor. Further, correlation and random-forest analysis (RFA) identified amylose as the most influential factor in starch-protein interactions affecting rice eating quality, followed by amylopectin and protein. RFA also revealed that in high AC japonica rice, the interactions of Fb3 and albumin with amylose were more conducive to forming good eating quality. In low AC japonica rice, the interactions of Fb2 and prolamin with amylose were more beneficial.


Assuntos
Oryza , Amido , Amido/química , Amilopectina/química , Amilose/química , Oryza/química , Rios
4.
Carbohydr Polym ; 330: 121785, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368080

RESUMO

The relationship between the fine structure of starch and its gelatinization properties is not well studied, particularly in relation to the influence of sugar or sugar alcohol. In this study, seven starches with distinct molecular structures were investigated to determine how different sugars and sugar alcohols affect their gelatinization properties. The inclusion of sugars and sugar alcohols resulted in a significant elevation of starch gelatinization temperatures (∼ 8 °C), especially with sucrose, isomaltose and isomalt. Nevertheless, the influence of these sugars/ sugar alcohols on the gelatinization temperature range and enthalpy change varied depending on the particular starch varieties. According to the correlation analysis, sugars and sugar alcohols mainly exert their impact on the starch gelatinization temperature range and enthalpy change by possibly interacting with amylose chains possessing a degree of polymerization ranging from 100 to 1000 (p < 0.05) and inhibiting the amylose leaching during gelatinization. These findings help a better understanding of the complex relationship between starch fine structure and gelatinization properties under the influence of sugars and sugar alcohols.


Assuntos
Amilose , Amido , Amido/química , Amilose/química , Estrutura Molecular , Álcoois Açúcares , Açúcares , Amilopectina/química
5.
Carbohydr Polym ; 330: 121791, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368094

RESUMO

This work aimed to evaluate the structure and functional characteristics of starch from ten hulled oat cultivars grown in different locations in China. The protein, phosphorus, amylose, and starch contents were 0.2-0.4 %, 475.7-691.8 ppm, 16.2-23.0 %, and 93.6-96.7 %, respectively. All the starches showed irregular polygonal shapes and A-type crystallization with molecular weights ranging from 7.2 × 107 to 4.5 × 108 g/mol. The amounts of amylopectin A (DP 6-12), B1 (DP 13-24), B2 (DP 25-36), and B3 (DP > 36) chains were in the ranges of 10.3-16.0 %, 54.5-64.8 %, 16.5-21.1 %, and 4.9-13.1 %, respectively. The starches differed significantly in gelatinization temperatures, pasting viscosity, solubility, swelling power, rheological properties, and digestion parameters. The results revealed that the larger particle size could increase the peak viscosity of the starch paste. The presence of phosphorus increased the gelatinization temperature and enhanced the resistant starch content. The starch granules with higher crystallinity contained a higher proportion of phosphate, which increased final viscosity and setback viscosity but decreased rapidly digestible starch. Overall, oat starch with a high phosphorus content could be used to prepare low-glycemic-index food for diabetes patients.


Assuntos
Avena , Amido , Humanos , Amido/química , Avena/metabolismo , Amilopectina/química , Amilose/química , Viscosidade , Grão Comestível/metabolismo , Fósforo
6.
Carbohydr Polym ; 330: 121826, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368105

RESUMO

Zinc deficiency is a serious risk to human health and growth, especially in children. The development of zinc supplements can effectively reduce this harm. Here, a series of debranched starch­zinc complexes (DS-Zn) were prepared, whose zinc complexation was inversely proportional to the amylopectin content in the debranched starch (DS). The physicochemical properties of DS-Zn were characterized using the conductivity, XRD, iodine staining and thermogravimetry. Combined with XPS, solid-state 13C NMR and IR, it was elucidated that the structure of DS-Zn is endoconcave structure with 2-O and 3-O of DS on the inner side and 6-O of DS on the outer side, where zinc is located. The DS-Zn exhibits good biosafety including blood, cellular and mutagenicity. In vitro simulations of digestion and zinc-deficient cellular models showed that DS-Zn was more tolerant to the gastrointestinal environment and more effective in zinc supplementation (increased by 33 %) than inorganic zinc supplements. Utilizing the compressibility of starch, DS-Zn was prepared as a more palatable oral cartoon tablet for children. This study will provide important support to advance the development and application of novel starch-based zinc nutritional supplements.


Assuntos
Amido , Zinco , Criança , Humanos , Amido/química , Zinco/química , Amilopectina , Espectroscopia de Ressonância Magnética
7.
Food Chem ; 444: 138622, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38310779

RESUMO

Three cultivars of waxy rice starch with different multi-scale structures were subjected to α-amylase hydrolysis to determine amylopectin fine structure, production of oligosaccharides, morphology, and crystallinity of the partially hydrolyzed starch granules. α-amylases hydrolyzed the amylopectin B2 chain during the initial stage of hydrolysis, suggesting that it is primarily located in the outer shell of the granules. For waxy rice starch with loose structure, α-amylases attacked the crystalline and amorphous regions simultaneously in the initial stage, while for starch granules with compact structure, the outer shell blocklet (crystalline structure) can be a hurdle for α-amylases to proceed to hydrolysis of the internal granule structure. The ability of α-amylases from porcine pancreatic α-amylases to attack the outer shell crystalline structure was lower than that of α-amylases from Bacillus amyloliquefaciens and Aspergillus oryzae. These results show that α-amylase source and rice cultivar combinations can be used to generate diverse structures in degraded waxy rice starch.


Assuntos
Oryza , Amido , Amido/química , Amilopectina/química , alfa-Amilases/metabolismo , Hidrólise , Oryza/química
8.
Carbohydr Polym ; 331: 121860, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38388056

RESUMO

Potato starch with mutations in starch branching enzyme genes (SBEI, SBEII) and granule-bound starch synthase gene (GBSS) was characterized for molecular and thermal properties. Mutations in GBSS were here stacked to a previously developed SBEI and SBEII mutation line. Additionally, mutations in the GBSS gene alone were induced in the wild-type variety for comparison. The parental line with mutations in the SBE genes showed a âˆ¼ 40 % increase in amylose content compared with the wild-type. Mutations in GBSS-SBEI-SBEII produced non-waxy, low-amylose lines compared with the wild-type. An exception was a line with one remaining GBSS wild-type allele, which displayed ∼80 % higher amylose content than wild-type. Stacked mutations in GBSS in the SBEI-SBEII parental line caused alterations in amylopectin chain length distribution and building block size categories of whole starch. Correlations between size categories of building blocks and unit chains of amylopectin were observed. Starch in GBSS-SBEI-SBEII mutational lines had elevated peak temperature of gelatinization, which was positively correlated with large building blocks.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana , Solanum tuberosum , Sintase do Amido , Amilopectina/química , Sintase do Amido/genética , Sintase do Amido/metabolismo , Amilose , Solanum tuberosum/metabolismo , Estrutura Molecular , Amido/química , Mutação , Enzima Ramificadora de 1,4-alfa-Glucana/química
9.
Carbohydr Polym ; 329: 121770, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286545

RESUMO

The complete dissolution of starch without degradation are necessary prerequisites for starch fractionation to obtain amylose or amylopectin (AP). With the recent, continuous progress in finding efficient and eco-friendly starch-dissolving solutions, applying new solvents for starch fractionation is important. In this study, the effects of dimethyl sulfoxide (DMSO), NaOH, and CaCl2 solutions on starch structure and AP product parameters during starch fractionation were compared with respect to the starch deconstruction effect. This study proved that the CaCl2 solution could effectively dissolve corn starch (50 °C, solubility of 98.96 %), and promote the regeneration of starch into uniform and fine particles. Furthermore, the three solvents (DMSO, NaOH, and CaCl2) changed the crystal structure of corn starch, but they were all non-derivatizing solvents. The effect of the CaCl2 solution on the molecular structure of corn starch was the least significant of the three solvents. Finally, the extraction rate of AP from the CaCl2 solution reached 69.45 %. In conclusion, this study presents a novel and effective method for AP extraction.


Assuntos
Amilopectina , Amido , Amido/química , Amilopectina/química , Zea mays/química , Dimetil Sulfóxido/química , Cloreto de Cálcio , Hidróxido de Sódio , Amilose/química , Solventes
10.
Int J Biol Macromol ; 254(Pt 1): 127765, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287575

RESUMO

Waxy maize starch serves as a pivotal component in global food processing and industrial applications, while high temperature (HT) during the grain-filling stage seriously affects its quality. Salicylic acid (SA) has been recognized for its role in enhancing plant heat resistance. Nonetheless, its regulatory effect on the quality of waxy maize starch under HT conditions remains unclear. In this study, two waxy maize varieties, JKN2000 (heat-tolerant) and SYN5 (heat-sensitive) were treated with SA after pollination and then subjected to HT during the grain-filling stage to explore the effect of SA on grain yield and starch quality. The results indicate that exogenous SA under HT treatment led to an increase in kernel weight and starch content in both varieties. Moreover, SA reduced the HT-induced holes on the surfaces of starch granules, enlarged the starch granule size, elevated the amylopectin branching degree, and reduced amylopectin average chain length. Consequently, improvements of pasting viscosity and the decrease of retrogradation percentage of starch were observed with SA under HT. Exogenous SA reduced HT-induced rapidly digestible starch content in SYN5, but had no significant effect on that in JKN2000. In summary, SA pretreatment effectively alleviated the detrimental effects of HT on starch pasting and thermal properties of waxy maize.


Assuntos
Amilopectina , Amido , Amido/química , Amilopectina/química , Zea mays/química , Ceras/química , Grão Comestível , Resposta ao Choque Térmico , Digestão
11.
Food Chem ; 441: 138280, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38176139

RESUMO

In this study, waxy corn starch (WCS) was modified by amylosucrase and pullulanase, producing linear starch chains with elongated length that favored the complexation with unsaturated fatty acids (uFAs). Compared to native WCS, the amylosucrase-modified WCS with an average chain length of 47.8 was easier to form V-type complexes with oleic acid, while increasing the degree of unsaturation impeded the formation of V-type complexes. The pullulanase treatment hydrolyzed the branching points of amylosucrase-modified WCS and the linear starch chains could forme V-type complexes with oleic acid, linoleic acid, and linolenic acid, with V-type crystallinity decreasing from 38.2 % to 20.1 %. V-type complexes had a lower thermal stability than the B-type starch crystallites, and their peak melting temperature ranged from 67.2 to 79.0 °C. The content of resistant starch in the complexes was in the range of 21.8 %-40.9 % and the formation of V-type complexes decreased the susceptibility of uFAs to oxygen.


Assuntos
Amilopectina , Amido , Amido/química , Amilopectina/química , Ácidos Graxos Insaturados , Temperatura , Ácido Oleico , Zea mays/química , Ácidos Graxos
12.
Int J Biol Macromol ; 260(Pt 1): 129408, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228203

RESUMO

This study aimed to investigate the role of amylose and amylopectin in the formation of starch-polyphenol complex and elucidate the interaction mechanisms. Gallic acid (GA) was used to complex with maize starch with various amylose contents. Results showed GA formed V-type crystals with normal maize starch (NMS) and high amylose maize starch (HAMS), while higher relative crystallinity was exhibited in HAMS-GA complexes than NMS counterparts. Molecular structure analysis revealed more amylose in GA-starch complexes than in treated starch counterparts without GA, and this was more apparent in HAMS than NMS, implying amylose is preferred to complex with GA than amylopectin. FTIR detected higher R1047/1022 value in starch-GA complexes than their starch counterparts without GA, suggesting increased short-range ordered structrure of complexes. Typical signatures of hydrophobic interactions were further revealed by isothermal titration calorimetry, indicating the complexation of GA to starch is mainly through hydrophobic bonds. More binding sites were observed for HAMS (72.50) than NMS (11.33), which proves the preferences of amylose to bind with GA. Molecular dynamics simulated the complexation of GA to amylose, and confirmed hydrophobic bond is the main interaction force. These findings would provide guidance for precise design and utilization of starch-polyphenol complexes in functional foods.


Assuntos
Amilose , Amido , Amido/química , Amilose/química , Amilopectina/química , Ácido Gálico/metabolismo , Zea mays/química , Interações Hidrofóbicas e Hidrofílicas , Polifenóis/metabolismo
13.
Int J Biol Macromol ; 260(Pt 1): 129421, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228206

RESUMO

The quantitative analysis and spatial chemical visualization of amylopectin and amylose in different varieties of sweet potatoes were studied by merging spectral and image information. Three-dimensional (3D) hyperspectral images carrying 1D spectra and 2D images of hundreds of the samples (amylopectin, n = 644; amylose, n = 665) in near-infrared (NIR) range of 950-1650 nm (426 wavelengths) were acquired. The NIR spectra were mined to correlate with the values of the two indexes using a linear algorithm, generating a best performance with correlation coefficients and root mean square error of prediction (rP and RMSEP) of 0.983 and 0.847 g/100 mg for amylopectin, and 0.975 and 0.500 g/100 mg for amylose, respectively. Then, 14 % of the wavelengths (60 for amylopectin, 61 for amylopectin) were selected to simplify the prediction with rP and RMSEP of 0.970 and 1.103 g/100 mg for amylopectin, and 0.952 and 0.684 g/100 mg for amylose, respectively, comparable to those of full-wavelength models. By transferring the simplified model to original images, the color chemical maps were created and the differences of the two indexes in spatial distribution were visualized. The integration of NIR spectra and 2D image could be used for the more comprehensive evaluation of amylopectin and amylose concentrations in sweet potatoes.


Assuntos
Ipomoea batatas , Solanum tuberosum , Amilopectina , Amilose/análise , Amido , Algoritmos
14.
Int J Biol Macromol ; 260(Pt 2): 129328, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242403

RESUMO

Pulsed electric field (PEF) technology was used to extract starch from Q. robur flours using low-intensity electric fields (0 and 0.1 kV/cm) and study the impact of PEF on the structure and properties of acorn starch concerning commercial starch. PEF technology is an advantageous method for starch extraction than the aqueous steeping from an industrial perspective since reduces extraction time and allows for continuous processing of larger suspension volumes. PEF technology preserved the amylose and amylopectin contents, hydrogen bonds, and diffraction patterns, as well as the starch native properties. Hence, PEF could be used to obtain native starches, but future studies should verify its economic viability. Acorn starches have lower damaged starch content, gelatinization temperatures, enthalpies, improved pseudoplastic behavior, reduced in-vitro digestibility, and lower resistance to deformation compared to commercial corn starch. The higher solubility and swelling power of acorn starches up to 80 °C make them a suitable food additive in fermented yogurt and milk products and thus help to value acorn and acorn starches. Hence, acorns can be used to obtain native starches, a food ingredient with a wide range of food and non-food usage, using PEF.


Assuntos
Quercus , Amido , Amido/química , Quercus/química , Amilopectina/química , Amilose/química , Temperatura
15.
Int J Biol Macromol ; 260(Pt 2): 129508, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266836

RESUMO

Corn starch was gelatinized by high hydrostatic pressure (HHP) and spray drying to make amorphous granular starch (AGS), and their physicochemical properties were compared with the conventionally prepared (heat-gelatinized and spray dried) AGS to devise a novel AGS preparation methodology. Pressure-induced (PAGS) and heat-induced AGS (HAGS) maintained their granular shape but lost their birefringence indicating that both methods could prepare AGS. DSC (differential scanning calorimeter) and XRD (X-ray diffraction) analysis confirmed the complete loss of amylopectin double helices and crystallinity of both PAGS and HAGS. However, their swelling power, solubility, RVA pasting properties, acid/shear stability, gel forming ability and textural properties were completely different. PAGS exhibited constrained swelling, suppressed amylose leaching, and reduced viscosity. Notably, HAGS formed a gel without heating, whereas PAGS yielded a viscous paste with water-soluble attributes. Even after reheating, PAGS maintained its granular structure with comparably less swelling and weaker gel strength than HAGS. Consequently, newly developed PAGS exhibited distinctive characteristics compared to the conventional HAGS, such as lower solubility and swelling power, viscosity, textural properties, and high acid and shear stabilities, rendering it a viable option for various applications within the food industry.


Assuntos
Secagem por Atomização , Amido , Amido/química , Pressão Hidrostática , Amilose/química , Amilopectina/química , Viscosidade
16.
Int J Biol Macromol ; 259(Pt 1): 129183, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176498

RESUMO

The emulsion was prepared with peanut oil and corn starch with different amylose content using high-speed homogenization assisted high-pressure homogenization, and the effect of starch-based emulsion on the gel properties, whiteness, microstructure, protein secondary structure, chemical forces, texture and sensory properties of Nemipterus virgatus surimi was investigated. The results showed that high amylose corn starch was more beneficial to the stability of emulsion than normal and waxy starch. The gel strength, water holding capacity and texture properties of surimi were significantly improved by adding 10 % waxy corn starch-based emulsion or 15 % high amylose or normal corn starch-based emulsion. Moreover, the whiteness of surimi gel containing starch-based emulsion was higher, and the microstructure was more compact and delicate than that of surimi without emulsion. The addition of starch-based emulsion could increase the hydrophobic interaction and disulfide bond content, and promote the transformation of protein secondary structure to irregular direction. The sensory properties such as color, texture, taste and overall acceptability could be improved to varying degrees. Therefore, starch-based emulsion could be used to enhance the gel properties and nutritional value of surimi products.


Assuntos
Amilose , Amido , Animais , Amilose/química , Amido/química , Emulsões , Géis/química , Peixes , Amilopectina
17.
Int J Biol Macromol ; 259(Pt 1): 129139, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176497

RESUMO

Normal and waxy maize starches with and without removal of starch granule surface lipids (SGSLs) were crosslinked by POCl3 (0.01 %, 0.1 % and 1 %). Crosslinked starches showed lower swelling power and solubility, but higher pasting viscosity, pseudoplasticity, thixotropy, storage modulus and loss modulus. Crosslinking increased the double helical structure but decreased the crystallinity for waxy maize starch. The phosphorus content of crosslinked waxy maize starches after SGSLs removal increased, indicating SGSLs removal promoted crosslinking. SGSLs removal increased G' and G" for crosslinked waxy maize starches. SGSLs removal increased SP and solubility and decreased pasting and rheological parameters of starches. With increased POCl3 dosage, the effect of SGSLs removal on starch properties was gradually suppressed by crosslinking. Waxy and normal maize starches showed significantly different changes with crosslinking and SGSLs removal, and the presence of amylose seemed to impede the effect of crosslinking and SGSLs removal. The removal of SGSLs could extend the application of crosslinked starch in frozen foods, drinks, and canned foods as thickener and stabilizer, due to its better hydrophilicity and viscous liquid-like rheological properties. The study will assist carbohydrate chemists and food processors in developing new food products.


Assuntos
Amido , Zea mays , Zea mays/química , Amido/química , Amilose/química , Amilopectina/química , Viscosidade , Ceras/química
18.
Nat Struct Mol Biol ; 31(2): 255-265, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177679

RESUMO

Resistant starch is a prebiotic accessed by gut bacteria with specialized amylases and starch-binding proteins. The human gut symbiont Ruminococcus bromii expresses Sas6 (Starch Adherence System member 6), which consists of two starch-specific carbohydrate-binding modules from family 26 (RbCBM26) and family 74 (RbCBM74). Here, we present the crystal structures of Sas6 and of RbCBM74 bound with a double helical dimer of maltodecaose. The RbCBM74 starch-binding groove complements the double helical α-glucan geometry of amylopectin, suggesting that this module selects this feature in starch granules. Isothermal titration calorimetry and native mass spectrometry demonstrate that RbCBM74 recognizes longer single and double helical α-glucans, while RbCBM26 binds short maltooligosaccharides. Bioinformatic analysis supports the conservation of the amylopectin-targeting platform in CBM74s from resistant-starch degrading bacteria. Our results suggest that RbCBM74 and RbCBM26 within Sas6 recognize discrete aspects of the starch granule, providing molecular insight into how this structure is accommodated by gut bacteria.


Assuntos
Glucanos , Amido , Humanos , Amido/química , Amido/metabolismo , Glucanos/química , Glucanos/metabolismo , Amilopectina/metabolismo , Ruminococcus/metabolismo , Bactérias/metabolismo
19.
Food Funct ; 15(4): 1923-1937, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38261274

RESUMO

The effects of fermentation on barley starch were studied using Lactiplantibacillus plantarum dy-1. Changes in multi-scale structure and physicochemical properties of barley starch were studied. The chain structure results revealed that fermentation could increase the content of short chain and medium short chain by breaking down long amylopectin side chains in barley and increase amylose content by debranching amylopectin. Also, fermentation promoted the arrangement of short chains into short order structure, leading to the enhancement of hydrogen bond interaction. Furthermore, it improved the helical structure content and relative crystallinity of barley starch by degrading the amorphous structure of barley starch. In terms of physicochemical properties, fermentation inhibited the hydration characteristics of barley starch, thus improving its thermal stability. It also enhanced shear stability, resistance to short-term aging and digestion, and improved gel texture properties. These findings offer potential for the processing and nutritional regulation of fermented barley products.


Assuntos
Hordeum , Amido , Amido/química , Amilopectina/química , Hordeum/química , Fermentação , Amilose/química
20.
Carbohydr Polym ; 327: 121702, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171666

RESUMO

The chain structure of starch affects its interaction with polyphenol molecules which in turn determines the nutritional function of starch. In this study, starch with different amylose content including waxy maize starch (WMS), normal maize starch (NMS) and G50 high-amylose maize starch (G50) were selected to complex with resveratrol (RA) in high-pressure homogenization (HPH) environment, and structural changes of the complexes, together with their effects on in vitro digestibility and gut microbiota were discussed. The results showed that with increasing amylose content, RA could form more inclusion complex with starch through non-covalent bonds accompanied by the increased single helix structure, V-type crystalline structure, compact nano-aggregates and total ordered structure content, which thus endowed the complex lower digestibility and intestinal probiotic function. Notably, when RA addition reached 3 %, the resistant starch (RS) content of HP-G50-3 % rose to 29.2 %, correspondingly increased the relative abundance of beneficial gut microbiota such as Megamonas and Bifidobacterium, as well as the total short-chain fatty acids (SCFAs) content. Correlation analysis showed that V-type crystalline structure positively correlated with the growth of Pediococcu and Blautia (p < 0.05) for producing SCFAs. These findings provided feasible ideas for the development of personalized nutritional starch-based foods.


Assuntos
Amilose , Microbioma Gastrointestinal , Humanos , Amilose/química , Zea mays/química , Resveratrol , Amido/química , Amilopectina/química , Ácidos Graxos Voláteis
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