Polyamines mediate the effect of post-anthesis soil drying on starch granule size distribution in wheat kernels

Polyamines(PAs) are important endogenous plant growth regulators responding to environmental stress and mediating many physiological processes including grain filling in cereals.This study investigated whether PAs mediate the effect of post-anthesis soil drying on starch granule size distribution,starch content,and weight of superior and inferior kernels of wheat(Triticum aestivum L.).Two wheat cultivars were grown in pots.Three treatments,well-watered(WW),moderate soil drying(MD) and severe soil drying(SD),were imposed from 9 days post-anthesis until maturity.PA levels in kernels and small,medium and large granules were measured.The results showed that superior kernels had much higher free spermidine(Spd) and free spermine(Spm) concentrations,larger volumes of medium starch granules,and smaller-sized large granules than did inferior kernels under all the treatments.Compared to WW,MD significantly increased the concentrations of free Spd and free Spm,activities of soluble starch synthase and granule-bound starch synthase,volume of medium granules,and starch content and kernel weight of inferior kernels,and decreased the size of large granules.SD produced the opposite effect.Application of Spd or Spm to spikes produced effects similar to those of MD,and application of an inhibitor of Spd and Spm synthesis produced effects similar to those of SD.These results suggest that PAs mediate the effect of post-anthesis soil drying on starch biosynthesis in wheat kernels by regulating key enzymes in starch synthesis and that elevated PA levels under MD increase the volume of medium granules and kernel weight of inferior kernels.

Comparison of Starch Granule Size Distribution Between Hard and Soft Wheat Cultivars in Eastern China

Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai＇an Experimental Station of Shandong Agricultural University, Taian, Shandong, China, were examined in this study. The granule size distribution and amylose contents in wheat grains were studied and compared, and relationships between the properties were identified. A clear bimodal distribution of granule size was shown in all wheat cultivars. Volume distribution of starch granules shows the typical bimodal with peak values in the ranges of 5.6-6.1μm and 20.7-24.9μm, respectively. Also, granule surface area distribution was bimodal with peak values in the ranges of 2.4-3.2μm and 20.7-24.9μm, respectively. Number distribution of granules was a typical population with a peak value in the range of 0.54-1.05μm. Contributions from the granules 〈 2.8μm and 〈 9.9μm to the total volume were in the ranges of 94.2-95.1% and 99.7-99.9% of total number, respectively. Proportions of granules〈2.8μm, 2.8-9.9μm, 9.9-22.8μm, and 22.8-42.8μm were in the ranges of 12.9-14.3%, 28.4-31.1%, 33.5-35.6%, and 19.7-22.7% for hard wheat, and 10.3-13.9%, 26.6-28.1%, 32.7-34.6%, and 24.2-27% for soft wheat. Hard wheat had greater B-type granules （ 〈 9.9μm）, and had fewer granules of 22.8-42.8μm than soft wheat. Amylose content was positively related to volume percentage of granules 22.8-42.8μm, and negatively related to volume percentage of granules 2.8-22.8μm.

QTL mapping of starch granule size in common wheat using recombinant inbred lines derived from a PH82-2/Neixiang188 cross

Starch is a crucial component determining the processing quality of wheat(Triticum aestivum L.)-based products. Wheat starch generally contains A-type and B-type starch granules, having different effects on starch properties and end-use qualities. In the present study, 240 recombinant inbred lines(RILs) derived from a PH82-2/Neixiang 188 cross were grown in Anyang, Henan, China, during three cropping seasons. A-type and B-type granule contents were determined using a laser diffraction particle size analyzer, defined as the percentage of total starch volume. A total of 195 SSR and STS markers were used to construct a genetic map. QTL analysis was performed by composite interval mapping. Three QTL for A-type starch granule content were mapped on chromosomes 1DL, 7BL and 4AL, explaining5.6%, 5.2% and 3.8% of the phenotypic variation, respectively. These results provide useful information for improving starch quality in common wheat.

Exogenous Application of Abscisic Acid or Gibberellin Acid Has Different Effects on Starch Granule Size Distribution in Grains of Wheat

Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and the functionality of wheat products. Two high-yield winter wheat cultivars were used to evaluate the effects of the application of exogenous ABA or GA during the reproductive phase of the initial grain filling on starch granule size distribution and starch components in grains at maturity. The results indicated that a bimodal curve was found in the volume and surface area distribution of grain starch granules, and a unimodal curve was observed for the number distribution under all treatments. The exogenous ABA resulted in a significant increase in the proportions （both by volume and by surface area） of B-type （〈9.9 Ixm in diameter） starch granules, with a reduction in those of A-type （〉9.9 ~tm） starch granules, while, the exogenous GA3 led to converse effects on size distribution of those starch granules. The exogenous ABA also increased starch, amylose and amylopectin contents at maturity but significantly reduced the ratio of amylose to amylopectin. Application of GA3 significantly reduced starch content, amylopectin content but increased the ratio of amylose to amylopectin. The ratio of amylose to amylopectin showed a significant and negative relationship with the volume proportion of granules 〈9.9 μm, but was positively related to the volume proportion of granules 22.8-42.8 μm.

The Effect of Maize Grain Size on the Physicochemical Properties of Isolated Starch, Crude Maize Flour and Nixtamalized Maize Flours

Usually, the maize cob is formed by grains of medium size. However, the extremes have larger or smaller size grains. The objective of this study was to investigate the influence of grain size from the same hybrid on the physicochemical properties of isolated starch, crude maize flours and nixtamalized maize flours. Two hybrids, one from CIMMyT-Mexico called IMIC-254 and one commercial sample from Monsanto (Puma) were studied. The isolated starch granules from small, medium, and large grains exhibit the same size and distribution. The grain size has influence in the determination of cooking and steeping times;small grains reach these parameters faster than medium and large ones. The hardness of the grain size for both hybrids does not showed statistical differences between them. The starch from small, medium and large grains is mainly composed of amylopectin;this result is confirmed by X-ray diffraction and Megazine analysis. The apparent viscosity of the isolated starches of small grains showed statistically significant higher peak values. According to these results, it is possible to use small, medium, and large grains to obtain products with the same physicochemical properties, by adjusting the cooking and steeping times and Ca2+ content.

烟用接装纸原纸非挥发性物质总迁移量影响因素分析

针对各卷烟材料厂提出烟用接装纸原纸中非挥发性物质总迁移量的要求,比对分析四台纸机生产的烟用接装纸原纸中非挥发性物质总迁移量以及生产工艺的差异,结果表明:表面施胶对其影响最大,不进行表面施胶时非挥发性物质总迁移量值最低,使用表面施胶时,CMC对其影响要高于氧化淀粉,针对不同客户要求,要设定不同的施胶量标准,以保证能够完全满足客户要求,提高产品市场竞争力。

糙米粉粒径对糙米直条米粉品质的影响

[目的]改善糙米直条米粉品质。[方法]采用低温冲击磨制备平均粒径(D[4,3])分别为370,86,62,47,30μm的糙米粉,并分别制备糙米直条米粉,考察糙米直条米粉淀粉短程有序结构、晶体结构、蒸煮品质和质构特性。[结果]糙米直条米粉淀粉短程有序度和相对结晶度随着粒径的减小呈先升后降的趋势,硬度和咀嚼性也呈先升后降的趋势,由适中粒径(D[4,3]为86μm)糙米粉制作的糙米直条米粉的淀粉短程有序度和相对结晶度最高,硬度和咀嚼性最大,品质最好。[结论]适度粉碎有利于糙米粉中的淀粉在直条米粉制作过程中形成更有序的结构,提高糙米直条米粉的硬度和咀嚼性。

韧化处理辅助酶解法制备表面施胶淀粉及其对纸张机械性能的影响

本研究首先对玉米淀粉进行韧化处理,再通过淀粉酶解法制备表面施胶淀粉。探究了改性后淀粉的理化性质,及其对纸张机械性能的影响。结果表明,相比于玉米原淀粉,韧化处理可有效调控直链淀粉含量和淀粉结晶结构,以水分含量75%、处理温度60℃、处理时间24 h韧化处理制备的表面施胶淀粉可有效提高纸张机械性能,横向环压指数最大提升约3.7%,横向抗张指数最大提升约10.5%,纵向抗张指数最大提升约3.4%,耐破指数最大提升约10%。本研究从表面施胶淀粉短程有序性角度诠释了其对纸张机械性能的增强机制,为韧化处理制备表面施胶淀粉提供一定的理论依据与技术支撑。

丙酸酯化-叔胺化淀粉浆料的制备及其黏附性能

为改善淀粉浆料的黏附性能,以提升淀粉浆料对经纱的上浆质量,以丙酸酐(PA)为酯化剂,二甲氨基氯乙烷盐酸盐(DMC-HCl)为叔胺醚化剂,采用固定PA用量及改变DMC-HCl用量的方式,以水为介质,在弱碱性和低温条件下,对酸解淀粉(AHS)进行丙酸酯化-叔胺化处理,制备出一系列具有不同总取代度的丙酸酯化-叔胺化淀粉(PTAS)。对其进行化学结构表征、元素分析、颗粒形貌观察分析以及取代度测定,并对其与涤纶、涤/棉与棉粗纱间黏附性,以及浆液表面张力进行考察。结果表明:固定PA对AHS质量分数为4.63%、改变DMC-HCl用量为10~40 g,可制备出丙酸酯化程度为0.030、叔胺化程度为0.010~0.035的PTAS样品;化学结构表征与元素分析结合证实了PTAS的成功制备,PTAS颗粒仍保持颗粒态形貌,但部分颗粒表面产生损伤;这种复合变性能够明显改善淀粉对涤纶、棉纤维的黏附性能,提升淀粉浆液的表面活性,表现为PTAS对涤纶、涤/棉及棉3种粗纱的黏合力均明显高于AHS,表面张力明显低于后者;随着PTAS总取代度的增加,其表面张力逐渐降低、黏合力逐渐增大、对棉纤维黏附性的提升优于对涤纶纤维。

淀粉基微球的滴入法制备及性能

以玉米淀粉、木薯淀粉、糯玉米淀粉3种天然淀粉为原料,在高温糊化后以滴入法制备了淀粉基微球。采用SEM、DSC和XRD对淀粉基微球进行了表征。考察了淀粉种类、淀粉质量分数、针头孔径对淀粉基微球平均粒径的影响,探究了玉米淀粉基微球的α-淀粉酶酶解性能和在高温水溶液中的释放行为,并评价了玉米淀粉基微球负载亚甲基蓝(MB)的性能。结果表明,在糊化温度80℃、淀粉质量分数10.0%,采用内径0.21 mm的27 G型针头制备的3种淀粉基微球形貌均一,粒径介于1.0~1.5 mm之间,收率均>90%,微球内部存在不同程度的中空结构;淀粉基微球糊化放热峰基本消失、晶型改变(由典型的A型晶体结构转变为较弱的V型结晶结构)且结晶度显著降低;3种淀粉基微球平均粒径均随着淀粉质量分数和针头孔径的增大而增大,相同制备条件下,玉米淀粉基微球的平均粒径最大;玉米淀粉基微球经α-淀粉酶24 h酶解后(酶解率42.78%)基本转变为水溶物,比玉米淀粉(酶解率41.91%)有更高的酶解率;玉米淀粉基微球负载MB时,MB添加量过大会导致包封率下降、释放率增大,不利于负载。与其他玉米淀粉基载体(玉米淀粉、多孔玉米淀粉)相比,玉米淀粉基微球负载MB的载药量(2.01%±0.03%)和包封率(60.33%±0.90%)最大,在温度>70℃的水溶液中MB释放率最低,90℃水溶液中MB的释放率为73.17%±0.61%。

种植密度对沿淮玉米籽粒淀粉粒度分布与糊化特性的影响

分析不同种植密度对沿淮玉米籽粒中淀粉粒度分布与糊化特性的影响。以豫单132、京科968等13个玉米杂交品种为材料,设置56 250株/hm^(2)、67 500株/hm^(2)、77 250株/hm^(2)等3个种植密度,分析不同种植密度对玉米籽粒品质、淀粉粒度分布与糊化特性的影响。结果表明,在种植密度56 250~77250株/hm^(2)范围内,随着种植密度的增加,玉米籽粒的蛋白质和脂肪含量呈递减趋势,淀粉含量呈递增趋势,即淀粉/蛋白质比率增加。玉米籽粒大型淀粉粒体积和表面积百分比显著增加,小型淀粉粒却显著降低。增加种植密度后玉米淀粉的峰值黏度、低谷黏度、最终黏度和稀懈值等黏度参数均呈显著升高。相关分析表明,玉米籽粒峰值黏度等黏度参数与小、大型淀粉粒体积百分比呈正相关,与中型淀粉粒体积百分比呈显著或极显著负相关。说明种植密度影响玉米籽粒淀粉粒度分布、淀粉黏度参数和组分含量。

十二烷基化淀粉浆料的制备及浆纱性能

为了改善玉米淀粉浆膜脆、硬的缺点,对玉米淀粉氧化,在碱性条件下与溴代十二烷进行醚化反应,制备了具有优异韧性浆膜的十二烷基化淀粉浆料。采用红外光谱对制备的十二烷基化淀粉浆料进行表征,并对其浆液、浆膜各项性能指标进行测试;分别用含有十二烷基化淀粉和磷酸酯淀粉的浆料配方对14.6 tex纯棉纱线上浆并测试浆纱性能。结果表明:此制备方法能够将烷基链引入到淀粉结构上,得到十二烷基化淀粉浆料;十二烷基化淀粉浆料成膜后浆膜柔软,对棉纤维黏附力好;使用十二烷基化淀粉浆料浆纱,纱线毛羽降低率及纱线增强率均优于磷酸酯淀粉浆料的浆纱。

低取代度淀粉烷基羧酸单酯的烷基链长对涤纶上浆性能的影响

为在纺织经纱上浆中合理使用含有烷基羧酸单酯取代基的酯化淀粉,以酸解淀粉为原料,选取乙酸乙烯酯、丙酸酐、丁酸酐和己酸酐为酯化剂,分别进行化学变性处理,制备了4种取代度相近(0.018左右)、烷基羧酸单酯取代基的烷基链长逐渐增大的淀粉烷基羧酸单酯,即醋酸酯淀粉、丙酸酯淀粉、丁酸酯淀粉和己酸酯淀粉。以酸解淀粉为对比样,探究4种酯化变性对淀粉浆液性能及浆膜性能的影响,明确烷基羧酸单酯烷基链长对性能的影响规律。结果表明:部分淀粉颗粒经酯化变性后产生了一定损伤,颗粒表面形成了凹槽;在较低取代度下,4种淀粉烷基羧酸单酯浆液表观黏度与酸解淀粉浆液相比无明显不同,表明4种酯化变性对淀粉浆液黏度无明显影响;4种淀粉烷基羧酸单酯对涤纶的黏附力及其浆膜的断裂伸长率和耐屈曲性均优于酸解淀粉,且其性能随着烷基羧酸单酯取代基烷基链长的增加而逐渐增强,但浆膜断裂强度呈现与之相反的趋势。综合考虑实验结果,推荐4种淀粉烷基羧酸单酯中的己酸酯淀粉应用于涤纶的经纱上浆。

拔节期渍水对软质小麦淀粉粒度分布与糊化特性的影响

为明确拔节期渍水对软质小麦淀粉粒度分布与糊化特性的影响。在大田条件下,于2021—2023年,选用软质小麦品种华成麦1688和荃麦725为试验材料,设对照(CK)和渍水(WL)2种处理,在小麦拔节期进行连续10 d的渍水处理,研究拔节期渍水对软质小麦淀粉粒度分布及黏度参数的影响及其相互关系。结果表明,与对照相比,拔节期渍水胁迫通过降低小麦穗数、穗粒数及千粒重,从而降低小麦产量,籽粒湿面筋含量、蛋白质含量显著降低,淀粉含量显著增加。拔节期渍水胁迫抑制了小麦胚乳B淀粉的产生和生长,使小麦B型淀粉粒体积、表面积及数目百分比显著降低,其中主要影响2.8~10.0μm的淀粉粒;A型淀粉粒体积、表面积百分比显著增加,以影响其中10.0~22.0μm的淀粉粒为主,渍水胁迫对A型淀粉粒数目百分比无显著性影响。渍水胁迫后,面粉峰值黏度、低谷黏度、最终黏度、稀懈值及回升值显著增加。可见,拔节期渍水胁迫改变了小麦淀粉粒度分布,通过降低B型淀粉粒占比,增加A型淀粉粒占比,进而增加峰值黏度等黏度参数,最终影响小麦籽粒品质。

氧化-叔胺化淀粉的制备及其对羊毛低温性能的影响

为提高淀粉在羊毛经纱低温上浆中的应用效果,在碱性条件下,制备氧化玉米淀粉(OCS)并与醚化剂(二甲氨基甲酰氯)反应制备氧化-叔胺化淀粉(OTAS),使用扫描电子显微镜(SEM)和X射线能谱仪(EDS)对其进行了表征分析,并考察了这种变性对淀粉溶解度及其低温粘度及粘度热稳定性、粘附性、羊毛经纱上浆等性能的影响。结果表明,OTAS能有效降低淀粉的低温粘度,提高其低温粘度热稳定性,提高其溶解度及其对羊毛纤维的低温粘合性能,提升淀粉膜的溶胀度、溶解率,缩短水溶时间,降低膜脆性,具有更好的低温浆纱性能。随着取代度增加,OTAS的低温粘度、溶解度及其对羊毛纤维的低温粘附性能均逐渐提升,从而为OTAS在羊毛经纱低温上浆中的应用奠定了基础。

大小粒型藜麦籽粒表型、灌浆特性及淀粉合成酶活性的差异分析

【目的】籽粒大小是影响藜麦产量、商品性和加工特性的重要因素,考察灌浆期大小粒型藜麦籽粒表型、灌浆特性和淀粉合成酶活性的差异,可为大粒型藜麦品种的选育提供理论指导。【方法】选择千粒重大于5.0 g和小于3.0 g的藜麦材料各2份,在青海省农林科学院种质资源创新试验基地进行田间试验,比较自灌浆期始7 d、14 d、21 d和28 d籽粒表型、灌浆特性和淀粉合成酶活性等在大小粒型藜麦间的差异。【结果】(1)大小粒型藜麦籽粒面积、周长、直径、粒长、粒宽表型性状随着生育时期均极显著增大,且粒型间存在显著差异,并以籽粒面积和周长差异最大,大粒型藜麦分别显著高于小粒型藜麦9.12%~11.54%和21.49~23.92%。(2)灌浆期间大粒型藜麦百粒干质量始终显著高于同期小粒型藜麦,平均增幅在21.23%~31.04%;大小粒型藜麦灌浆速率随生育期均先上升后下降,均符合“慢—快—慢”的变化规律,但达到峰值时间和峰高明显不同,大粒型峰值出现早而高,小粒型则低而迟。(3)淀粉分支酶(SBE)、蔗糖合成酶(SS)、可溶性淀粉合成酶(SSS)和ADPG焦磷酸化酶(AGP)在大小粒型藜麦籽粒灌浆期呈现不同的变化趋势,SBE和SS活性表现为小粒型藜麦强于大粒型藜麦,而SSS和AGP活性则表现为大粒型藜麦强于小粒型藜麦。【结论】藜麦籽粒灌浆期间4种淀粉合成酶活性的差异,致使淀粉合成积累量和灌浆速率峰值的不同,进而形成籽粒表型性状的差异,而SSS和AGPase是影响藜麦籽粒大小形成的关键酶。

监控施肥配施有机肥和生物炭对小麦产量及籽粒淀粉理化特性的影响

为了明确不同施肥措施对冬小麦籽粒淀粉结构、理化特性和小麦籽粒产量的影响,以小麦品种洛旱6号为材料,通过裂区试验(以农户施肥和监控施肥2种施肥方式为主区,以不配施有机物料、配施有机肥和配施生物炭为副区),分析不同处理下冬小麦籽粒淀粉结构、理化特征及产量的差异。结果表明,与农户施肥方式相比,监控施肥显著增加了小麦籽粒总淀粉含量、直链淀粉含量和直支比,提高了A型淀粉粒的体积和数目百分比,显著提升了平均低谷黏度、最终黏度、稀懈值和回升值。在同一施肥方式下,与不配施有机物料相比,配施有机肥对总淀粉含量、直链淀粉含量、淀粉直支比、A型淀粉粒体积百分比和淀粉黏度参数也均表现出正向效应,同时降低了B型淀粉粒的体积和数目百分比,而配施生物炭对淀粉含量及直支比、A型淀粉粒体积及表面积分布影响均不显著。施用生物炭对淀粉糊化特性影响在不同施肥方式下存在差异,农户施肥+生物炭处理显著降低了峰值黏度、低谷黏度和最终黏度,而监控施肥+生物炭处理显著增加了峰值黏度、最终黏度、稀懈值和回升值。监控施肥对产量影响不显著,但监控施肥+配施有机肥处理显著提高产量。在所有处理中,监控施肥+配施有机肥处理的小麦籽粒淀粉含量、直支比、淀粉粒分布、淀粉黏度参数综合表现最好,说明在监控施肥条件下减少施用化肥同时配施有机肥可改善小麦淀粉品质和增加产量,促进渭北旱地冬小麦高产优质生产。

花后弱光对弱筋小麦淀粉粒度分布与黏度参数的影响

为探讨花后弱光对弱筋小麦淀粉粒度分布与黏度参数的影响,以弱筋小麦品种皖西麦0638、宁麦13为材料,设置开花后(开花期—成熟期)30%遮荫处理,分析了不同处理下弱筋小麦淀粉粒度分布与黏度参数及其相互关系。结果表明,与正常光照相比,花后弱光显著降低小麦穗粒数、千粒重、产量和容重,显著增加籽粒蛋白质含量、湿面筋含量及沉降值;显著降低B型淀粉粒体积、表面积及数目百分比,以影响2.8~10μm淀粉粒为主;增加A型淀粉粒体积、表面积及数目百分比,以影响10~22μm淀粉粒为主;显著降低小麦峰值黏度、低谷黏度、最终黏度、稀懈值及回升值。相关分析表明,弱筋小麦B型淀粉粒体积分布与峰值黏度、低谷黏度、最终黏度、稀懈值和回升值均呈显著正相关,与A型淀粉粒体积分布呈显著负相关。综上,花后弱光降低弱筋小麦产量、B型淀粉粒占比,增加A型淀粉粒占比;显著降低峰值黏度等黏度参数。

多元酯化淀粉在新型纤维品种中的上浆工艺

探讨多元酯化淀粉JF-999的浆料性能,替代PVA用于新型纤维纱线上浆的效果。对比测试JF-999浆料和常规PVA浆料的浆液和浆纱性能,对两种配方的浆纱各项指标分析,以及织造生产效率对比。试验结果表明:JF-999多元酯化淀粉黏度及稳定性较好,与天竹等新型纤维具有良好的亲和性,且黏着力较好;浆纱质量稳定,好轴率较高,具有良好的浆纱增强和减伸效果,布机效率提升明显;易退浆、无污染,完全符合绿色环保要求,可以替代PVA用于新型纤维品种的经纱上浆。

THE ADHESIVE CAPACITY OF STARCH GRAFT COPOLYMERS TO POLYESTER/COTTON FIBER

The advantages of using starch graft copolymers as warp sizes in textile were briefly discussed, and the factors of affecting adhesive capacity to the fiber were analysed. By using eerie ammonium nitrate as an initiator under nitrogen atomosphere, a number of vinyl and/or acrylic monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, butyl methacrylate, vinyl acetate and the combinations among them were graft copolymerized respectively onto granular corn starch in aqueous dispersion. The adhesive capacity of these starch graft copolymers to polyester/cotton fibers was evaluated by a slightly sized rovings according to V. K. Aggarwal’s method which measures the breaking strength and elongation of the rovings impregnated with the size paste. The influences of the monomers and their combinations, the grafting technological processes and the pretreatment methods before graft copolymerization upon adhesive capacity have been