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1.
Improving cereal grain carbohydrates for diet and health 总被引：1，自引：0，他引：1
Starch and cell wall polysaccharides (dietary fibre) of cereal grains contribute to the health benefits associated with the consumption of whole grain cereal products, including reduced risk of obesity, type 2 diabetes, cardiovascular disease and colorectal cancer. The physiological bases for these effects are reviewed in relation to the structures and physical properties of the polysaccharides and their behaviour (including digestion and fermentation) in the gastro-intestinal tract. Strategies for modifying the content and composition of grain polysaccharides to increase their health benefits are discussed, including exploiting natural variation and using mutagenesis and transgenesis to generate further variation. These studies will facilitate the development of new types of cereals and cereal products to face the major health challenges of the 21st century. 相似文献
2.
Massimiliano CarciofiShahnoor S. Shaik Susanne L. Jensen Andreas BlennowJan T. Svensson Éva VinczeKim H. Hebelstrup 《Journal of Cereal Science》2011,54(3):339-346
Plant starch is naturally phosphorylated at a fraction of the C6 and the C3 hydroxyl groups during its biosynthesis in plastids. Starch phosphate esters are important in starch metabolism and they also generate specific industrial functionality. Cereal grains starch contains little starch bound phosphate compared with potato tuber starch and in order to investigate the effect of increased endosperm starch phosphate, the potato starch phosphorylating enzyme glucan water dikinase (StGWD) was overexpressed specifically in the developing barley endosperm. StGWD overexpressors showed wild-type phenotype. Transgenic cereal grains synthesized starch with higher starch bound phosphate content (7.5 (±0.67) nmol/mg) compared to control lines (0.8 (±0.05) nmol/mg) with starch granules showing altered morphology and lower melting enthalpy. Our data indicate specific action of GWD during starch biosynthesis and demonstrates the possibility for in planta production of highly phosphorylated cereal starch. 相似文献
3.
Enpeng Li Jovin Hasjim Sushil Dhital Ian D. Godwin Robert G. Gilbert 《Journal of Cereal Science》2011
Inhibition of plant growth by Trinexapac-ethyl, TE, a gibberellin-biosynthesis inhibitor, can produce a shorter stemmed plant, requiring less nutrients and water to grow, while maintaining grain yield. Although TE and other plant growth regulators are commonly used in grain crops, their effects on starch biosynthesis in the grains have not been systematically examined. The changes in the structural and functional properties of starch in grains harvested from TE-treated sorghum (Sorghum bicolor (L.) Moench) were examined, and the results compared with those from the untreated controls. TE treatment had little or no effects on the molecular structures of starch, starch granule morphology, and starch and amylose contents, but increased the protein content of the grains significantly. Consistent with the lack of change in the molecular structure, there were no significant effects on the thermal properties of the starch. The pasting properties of TE-treated sorghum flours, however, showed lower peak viscosity, trough, and final viscosity, which were attributed to their higher protein contents. The TE treatment thus does not have an appreciable effect on the biosynthesis of starch during grain development in sorghum. 相似文献
4.
The starchy endosperm of the mature wheat grain comprises three major cell types, namely sub-aleurone cells, prismatic cells and central cells, which differ in their contents of functional components: gluten proteins, starch, cell wall polysaccharides (dietary fibre) and lipids. Gradients are established during grain development but may be modified during grain maturation and are affected by plant nutrition, particularly nitrogen application, and environmental factors. Although the molecular controls of their formation are unknown, the high content of protein and low content of starch of sub-aleurone cells, compared to the other starchy endosperm cells types, may result from differences in developmental programming related to the cells having a separate origin (from anticlinal division of the aleurone cells). The gradients within the grain may be reflected in differences in the compositions of mill streams, particularly those streams enriched in the central and outer cells of the starchy endosperm, respectively, allowing the production of specialist flours for specific end uses. 相似文献
5.
This review deals with the biochemical basis and implications of hardness and grain strength in sorghum and maize. Grain hardness affects various aspects of the growth and processing of cereal grain from resistance to fungal infection to cooking quality. It is clear that the prolamins play an important role with the γ-prolamins being the most important. It would appear that these prolamins help shape the protein bodies and form disulphide bonds within themselves or with other proteins. The γ-prolamins form the cement while the α-prolamins are the bricks. Both prolamins are present in greater proportions in hard grains and in the vitreous portion of hard grains. Genetic and environmental effects on the amounts of the different prolamins and on their distributions within the protein body and in different parts of the endosperm also determine grain hardness. Grains that will be hard appear to deposit prolamins and antifungal proteins earlier and in greater amount than do soft grains. The cell wall composition is also different between the two types of grains while there is a higher proportions of amylose in the starch of hard than in that of soft grains. Most of the differences that exist between hard and soft grains also exist between the outer and inner portion of the grain. It is postulated that there might be a master gene controlling the onset of strength in grains by simultaneously altering the levels of various apparently unrelated biochemical events. It is also suggested that solute availability may play an important role in the regulation of expression of genes for hardness-related proteins. 相似文献
6.
糯小麦与酿酒谷物黏度特性的比较 总被引：2，自引：0，他引：2
为明确糯小麦与其他酿酒谷物糊化特性的差异,为糯小麦在白酒酿造中的应用提供参考依据,比较分析了CD糯麦-2、普通小麦、糯米、高粱和玉米籽粒的淀粉RVA黏度特性。结果表明,不同作物的糊化特性有很大的差异,高梁的峰值黏度最高,糯小麦次之,玉米最低,普通小麦比糯米高,但二者差异较小;到达峰值黏度的时间为5.2~11.2 min,其中糯米糊化最快,糯小麦与糯米接近,比普通小麦快近2 min,普通小麦与高粱相近,玉米最慢;到达峰值黏度的温度为67.2~92.2℃,其中糯小麦和糯米低,分别为70.3℃和67.2℃,普通小麦和高粱分别为84.6℃和83.1℃,玉米则高达92.2℃,糯小麦比普通小麦低约14.3℃。糯小麦配粉能改变谷物的黏度特性,对糊化温度和糊化时间的影响小于对峰值黏度的影响,从不同作物考虑,糯小麦配粉对糯米的黏度特性影响相对较小。结果显示,糯小麦像糯米一样直链淀粉含量极低,其淀粉易糊化,糊化温度低,耗能少;向其他谷物中添加糯小麦可改变其淀粉黏度特性;糯小麦具有代替其他谷物酿造新型风味白酒的潜在优势。 相似文献
7.
Surface properties and locations of gluten proteins and lipids revealed using confocal scanning laser microscopy in bread dough 总被引：1，自引：0，他引：1
Surface properties of gluten proteins were measured in a dilation test and in compression and expansion tests. The results showed that monomeric gliadin was highly surface active, but polymer glutenin had almost no surface activity. The locations of those proteins in bread dough were investigated using confocal scanning laser microscopy and compared with polar and nonpolar lipids. Added gluten proteins participated in the formation of the film or the matrix, surrounding and separating individual gas cells in bread dough. Gliadin was found in the bulk of dough and gas ‘cell walls’. Glutenin was found only in the bulk dough. Polar lipids were present in the protein matrix and in gas ‘cell walls’, as well as at the surface of some particles, which appeared to be starch granules. However, nonpolar lipid mainly occurred on the surface of particles, which may be starch granules and small lipid droplets. It is suggested that the locations of gluten proteins in bread dough depends on their surface properties. Polar lipid participates the formation of gluten protein matrix and gas ‘cell walls’. Nonpolar lipids may have an effect on the rheological properties by associating with starch granule surfaces and may form lipid droplets. 相似文献
8.
Javier Echave Maria Fraga-Corral Pascual Garcia-Perez Jelena Popovi&#x;-Djordjevi&#x; Edina H. Avdovi&#x; Milanka Radulovi&#x; Jianbo Xiao Miguel A. Prieto Jesus Simal-Gandara 《Marine drugs》2021,19(9)
Seaweeds are industrially exploited for obtaining pigments, polysaccharides, or phenolic compounds with application in diverse fields. Nevertheless, their rich composition in fiber, minerals, and proteins, has pointed them as a useful source of these components. Seaweed proteins are nutritionally valuable and include several specific enzymes, glycoproteins, cell wall-attached proteins, phycobiliproteins, lectins, or peptides. Extraction of seaweed proteins requires the application of disruptive methods due to the heterogeneous cell wall composition of each macroalgae group. Hence, non-protein molecules like phenolics or polysaccharides may also be co-extracted, affecting the extraction yield. Therefore, depending on the macroalgae and target protein characteristics, the sample pretreatment, extraction and purification techniques must be carefully chosen. Traditional methods like solid–liquid or enzyme-assisted extraction (SLE or EAE) have proven successful. However, alternative techniques as ultrasound- or microwave-assisted extraction (UAE or MAE) can be more efficient. To obtain protein hydrolysates, these proteins are subjected to hydrolyzation reactions, whether with proteases or physical or chemical treatments that disrupt the proteins native folding. These hydrolysates and derived peptides are accounted for bioactive properties, like antioxidant, anti-inflammatory, antimicrobial, or antihypertensive activities, which can be applied to different sectors. In this work, current methods and challenges for protein extraction and purification from seaweeds are addressed, focusing on their potential industrial applications in the food, cosmetic, and pharmaceutical industries. 相似文献
9.
Sorghum is a staple food for half a billion people and, through growth on marginal land with minimal inputs, is an important source of feed, forage and increasingly, biofuel feedstock. Here we present information about non-cellulosic cell wall polysaccharides in a diverse set of cultivated and wild Sorghum bicolor grains. Sorghum grain contains predominantly starch (64–76%) but is relatively deficient in other polysaccharides present in wheat, oats and barley. Despite overall low quantities, sorghum germplasm exhibited a remarkable range in polysaccharide amount and structure. Total (1,3;1,4)-β-glucan ranged from 0.06 to 0.43% (w/w) whilst internal cellotriose:cellotetraose ratios ranged from 1.8 to 2.9:1. Arabinoxylan amounts fell between 1.5 and 3.6% (w/w) and the arabinose:xylose ratio, denoting arabinoxylan structure, ranged from 0.95 to 1.35. The distribution of these and other cell wall polysaccharides varied across grain tissues as assessed by electron microscopy. When ten genotypes were tested across five environmental sites, genotype (G) was the dominant source of variation for both (1,3;1,4)-β-glucan and arabinoxylan content (69–74%), with environment (E) responsible for 5–14%. There was a small G × E effect for both polysaccharides. This study defines the amount and spatial distribution of polysaccharides and reveals a significant genetic influence on cell wall composition in sorghum grain. 相似文献
10.
There is an amazing diversity of cell wall composition and cell wall polysaccharide structure in wheat grain that is only partly explained by the complexity of plant tissues and cell type functions present in this organ. This review presents the state of the art on the structure and diversity of cell wall polymers in mature wheat grain and recent knowledge on cell wall metabolism with a focus on development-associated changes in wheat grain cell wall polysaccharides and genes controlling their biosynthesis. The diversity of polysaccharide structure observed in endosperm cell walls is tentatively explained on the basis of polysaccharide properties and cell type function. 相似文献
11.
同源四倍体水稻胚乳发育:糊粉层细胞壁纤维素物质发育、胚乳淀粉积累及胼胝质“套”的形成 总被引：2，自引：0，他引：2
利用荧光显微术观察，发现同源四倍体水稻与其二倍体原种的糊粉层细胞壁纤维素物质都存在一个“充实”的过程。授粉后5～6 d，糊粉层开始分化形成，此时其细胞壁上未观察到纤维素物质；授粉后6～8 d，糊粉层细胞壁上开始积累纤维素物质；授粉后8～9 d，糊粉层细胞壁积累了大量的纤维素物质。胚乳淀粉的积累存在一个变化的过程：初生胚乳核周围可见一些淀粉体，随着胚乳游离核的增多，游离核周围淀粉体的数量逐渐减少，胚乳细胞化后，胚乳细胞内开始大量形成淀粉体。利用苯胺蓝染色连续切片荧光观察，发现同源四倍体水稻及其二倍体原种胚乳发育过程中，在珠心表皮和内珠被之间存在一层胼胝质物质，围绕着胚囊并包裹住珠心呈“套”状。这个结构的形成变化过程为：授粉后30 min在珠孔端珠心表皮细胞与内珠被之间开始积累少量的胼胝质，之后胼胝质逐渐增多并向合点端扩展延伸；授粉后1～2 d包裹着整个胚囊外的珠心而仅在维管束处断开；授粉后9～13 d，胼胝质“套”消失。该结构可能与胚和胚乳在发育期间的水分和养分的调节等有密切关系。同源四倍体水稻还存在糊粉层细胞壁发育不同步、糊粉层细胞壁结构异常以及胼胝质“套”不消失等异常现象。这些现象有可能会影响同源四倍体水稻的结实率。 相似文献
12.
Rubi G. Utrilla-Coello Edith Agama-Acevedo Ana Paulina Barba de la Rosa Jose L. Martinez-Salgado Sandra L. Rodriguez-Ambriz Luis A. Bello-Perez 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(1):18-24
The use of pigmented maize varieties has increased due to their high anthocyanins content, but very few studies are reported
about the starch properties of these grains. The aim of this work was to isolate the starch granules from pigmented blue maize
and carry out the morphological, physicochemical, and biochemical characterization studies. The proximate composition of starch
granules showed high protein contents, after purification, the blue maize starch presented lower protein amount than starch
from white maize (control). Although the purity of starch granules was increased, the damaged starch (determined for the Maltase
cross absence) was also increased. Scanning electron microscopy showed the presence of some pores and channels in the blue
maize starch. The electrophoretic protein profiles showed differences in the bands that correspond to the enzymes involved
in the starch biosynthesis; these differences could explain the variation in morphological characteristics of blue maize starches
against starch from white maize. 相似文献
13.
The effect of chemical composition of starch samples derived from selected wheat cultivars harvested in different years (lipid content, amylose–lipid complex (AML) content, amylose concentration and the degree of starch damage) on physicochemical properties of glucose syrups produced from these starches was determined. It was found that glucose syrups obtained from the same wheat cultivar but harvested in different years displayed different physicochemical attributes such as concentration of reducing compounds, rate of filtration and coefficients of colour and transparency. Besides, the analyses showed that AML changed their form from amorphous to crystalline during enzymatic starch liquefaction by α-amylase. This in turn rendered starch less susceptible to enzymatic digestion and affected physicochemical features of glucose syrups. Presented results provide evidence that not only the total concentration of lipids and AML but also the AML polymorph present in starch hydrolysates (on completion of starch liquefaction) have an impact on quality of glucose syrups. 相似文献
14.
15.
以水稻糖质胚乳突变体Sug-11与其野生型对照中花11为材料,通过对两者籽粒中可溶性总糖、蔗糖含量和淀粉含量以及有关淀粉品质理化指标的比较,结合籽粒灌浆过程中糖类物质含量、淀粉合成代谢关键酶活性和相关同工型基因转录表达水平的动态测定,从籽粒淀粉合成代谢角度,对水稻糖质突变体Sug-11的籽粒糖类含量变化和千粒重下降的生理原因进行了分析。结果表明,Sug-11糖质突变体与其野生型在灌浆初期的可溶性糖和蔗糖含量差异并不明显,随着籽粒灌浆进程,两者间的籽粒糖分含量差异在灌浆中后期逐步趋于明显;与野生型相比,Sug-11糖质胚乳突变体的稻米直链淀粉含量和直链淀粉碘蓝值显著下降,而淀粉溶解度和支链淀粉碘蓝值则显著升高,糖质胚乳突变对稻米淀粉的理化特性也产生了明显的影响;在籽粒淀粉合成代谢的几个关键酶中,Sug-11糖质突变体籽粒中的DBE活性及其在灌浆过程中的动态变化与其野生型存在明显差异,揭示了胚乳糖质突变体Sug-11籽粒中淀粉积累减少、糖分含量增加主要是由籽粒灌浆中后期的PUL转录表达水平和DBE活性的大幅下降所引起的,而Sug-11的籽粒灌浆不良和千粒重下降等现象,则与其ADPGase活性在籽粒灌浆前期的显著下降存在一定的联系。 相似文献
16.
Sindhu NairMichael Knoblauch Steven UllrichByung-Kee Baik 《Journal of Cereal Science》2011,54(3):354-362
Kernel hardness, an important quality trait of cereal grains, is known to influence pearling properties and malting quality of barley. To understand the endosperm micro-structural features of kernels and their relationship to kernel hardness, endosperms of three hard and three soft hulled spring barley lines based on single kernel characterization system hardness index were observed under light (LM) and scanning electron (SEM) microscopy. Under LM, endosperm cell wall of the three hard kernel lines was significantly thicker than that of the three soft kernel lines. Hard and soft lines showed differences in the degree of starch-protein association and continuity of protein matrix under the SEM. Hard kernel lines with a continuous protein matrix exhibited greater starch-protein adhesion than the soft kernel lines, suggesting that starch-protein binding may be one of the factors influencing barley kernel hardness. SEM of flour particles of soft kernel lines showed numerous well defined individual A and B-type starch granules, while, flour of hard kernel lines mostly showed small flour aggregates with few individual starch granules. 相似文献
17.
不同类型小麦品种大、小淀粉粒的分离和特性 总被引：10，自引：2，他引：8
为给小麦品质育种提供依据,以3个不同类型的小麦品种(济南17号、扬麦12号和扬麦9号)为材料,分离了大、小淀粉粒,并对它们的特性(形状、大小、膨胀势、晶体特性、糊化特性等)进行了测定和分析.结果表明,大、小淀粉粒形状为椭球形或球形,品种间无差别,但其大小和含量在品种间存在很大差异;大淀粉粒的膨胀势大于小淀粉粒.大、小淀粉粒都为A型淀粉晶体,大淀粉粒的相对结晶度差别不大,但小淀粉粒的相对结晶度差别较大,表现为济南17号＜扬麦12号＜扬麦9号.品种内大淀粉粒的起始温度To、峰值温度Tp值和吸收热焓△H高于小淀粉粒,终止温度Tc值却比小淀粉粒低. 相似文献
18.
Phospholipids are a major kind of lipids in rice grains and have fundamental nutritional and functional benefits to the plant. Their lyso forms(lysophospholipids, LPLs) often form inclusion complexes with amylose or independently influence the physicochemical and functional properties of rice starch. However, the genetic basis for LPL synthesis in rice endosperm is largely unknown. Here, we performed a preliminary association test of 13 LPL compositions among 20 rice accessions, and identified 22 putative main-effect quantitative trait loci responsible for all LPLs except for LPC14:0 and LPE14:0. Five derived cleaved amplified polymorphic sequences and one insertion/deletion marker for three LPL-synthesis-related candidate genes were developed. Association analysis revealed two markers significantly associated with starch LPL traits. These results provide an insight into the genetic basis of phospholipid biosynthesis in rice and may contribute to the rice quality breeding programs using functional markers. 相似文献
19.
Aybeke M 《Pakistan journal of biological sciences: PJBS》2011,14(2):146-148
In this study, investigation of some anther structures in Sanguisorba minor Scop. subsp. muricata was aimed. Therefore, anthers were squashed by modified glycerine-gelatine method and additionally different histochemical stainings also were tested. The result illustrated that in different parts of anther, such as marginal, connection tissue, starch and protein granules accumulated. Furthermore, during maturation these deposits were detected in pollen grains also. In addition, a very interesting feature, balloon-like structures filled by proteins, were observed in anther cavity. In the light of these findings, their importance on pollen development was discussed. 相似文献
20.
Edith K. Hüttner Fabio Dal Bello Kaisa Poutanen Elke K. Arendt 《Journal of Cereal Science》2009,49(3):363-370
The use of grains alternative to wheat or rye is a challenging task for cereal technologists, and currently new technologies are under investigation as tools to improve the performances of these alternative grains. In this work the effects of high Hydrostatic Pressure (HP) on oat batters were investigated. Oat batters were treated for 10 min at 200, 300, 350, 400 or 500 MPa. Scanning electron microscopy and bright field microscopy showed that high HP significantly affected oat batter microstructure, and both starch and proteins were affected. Treatment at high HP significantly improved batter viscosity and elasticity. At pressures ≤300 MPa the increase in the viscous component was higher than the increase in the elastic component. On the contrary, at pressures ≥350 MPa the elastic component was predominant. Differential scanning calorimetry revealed that high HP induced starch gelatinisation, which started at 300 MPa and was almost complete after treatment at 500 MPa. High HP also affected water- and salt-soluble as well as urea-soluble oat proteins. Analysis of proteins soluble in different buffers revealed that pressures ≥300 MPa induced the formation of urea-insoluble complexes and/or disulfide bonds. Overall, the extent of starch gelatinisation and protein modification was dependent on the applied pressure, but the results collected so far clearly show that high HP can be used to improve the functionality of oat batters. 相似文献