Construction of Vectors to Express Foreign Protein within Potato Starch Grains

[Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expression level of foreign protein. [Method] By using molecular biological techniques of RT-PCR and nested PCR, plant expression vector for the foreign protein locating in the potato starch grains was constructed. [ Result] Coding sequence （ GC20 ） of potato starch grains that was located and expressed by GBSSI promoter was cloned. Plant expression vector was screened out through connection, transformation and enzyme digestion identification. [ Conclusion] This result laid a foundation for further screening the foreign protein on the potato starch grains.

Morphological Change of Starch Grain Based on Simulated Experiment and its Significance of Agricultural Archaeology——Taking Wheat as an Example

[Objective] The aim was to research and identify starch grain microfossil found in archaeological sites in China, and to find appropriate procedures for the starch grain analysis experiment.[Method] Wheat starch grain size distribution was analyzed, and some simulated experiments were carried out, like mortar grinding, ultrasonic treatment, hydrochloric acid and hydrogen peroxide immersion, drying treatment, and so on. [Result] The mean size of wheat starch grains had increased in the growth process. Mortar grinding would make wheat starch grains larger than untreated sample. Long time of ultrasonic treatment can also make the starch grain size larger. 10% HCl and 6% H2O2 would have little effects on morphological feature of wheat starch grains. Low temperature heating did not cause starch grains to be gelatinized. [Conclusion] These experiment results can improve the accuracy of starch grain microfossil identification in the archaeological site. Starch grain analysis may be a utility and effective analytical tool in studying the origin of agriculture and the dispersal of crops in China.

Plant food sources and stone tools' function at the site of Shunshanji based on starch grain analysis

The upper-middle Huai River valley(HRV) is located in the transition zone in the middle of eastern China. Previous studies have shown that the past populations in the upper HRV obtained plant food through gathering and cultivation of both rice and millet during the middle Neolithic. However, for the middle HRV it is not very clear what methods were used by humans to obtain plant food in that time. In this paper, starch grain analysis was carried out on 17 stone tools and 29 cauldron pottery sherds unearthed at Shunshanji(8.5–7.0 kyr BP), which is known as the earliest Neolithic site in the middle HRV excavated so far. Here, ancient starches from Coix lacryma-jobi, Triticeae, Oryza sativa, Trichosanthes kirilowii and one unidentified specie were recovered. This study contributes to the limited knowledge of food strategies as observed in the middle HRV. It demonstrates that both gathering and cultivation of rice took place during the middle-Neolithic. Among the identified species, Coix lacryma-jobi appears to have been the main plant food at Shunshanji. Moreover, it is clear that Oryza sativa was not consumed as much as other plant species according to the occurrence frequency of different starch grains. Starch grains were also found on the used surfaces of grinding stone implements as well as pestles, which means that these stone tools were used for food processing. In addition, axes from Shunshanji may also have been used for food processing as well as wood working because starches were also found on the edge of axes. Information about subsistence strategies and tool use at Shunshanji will also be helpful to understanding the utilization of plants and agricultural development in the middle HRV during the early-middle Neolithic period.

Starch grain analysis reveals Late Neolithic plant utilization in the middle reaches of the Ganjiang River

Plant utilization is poorly known in South China as compared to North China.Fanchengdui, Zhuweicheng, Shinianshan, and Yinjiaping, which date back to 5-4 ka BP, are typical Neolithic sites located at the middle reaches of the Ganjiang River in Jiangxi Province.Due to the lack of systematic plant archaeological work, only rice straw and husk residues have been found in some archaeological sites in Jiangxi Province.Thirteen stone tools excavated from these sites were examined in this study.The results showed that among the plants utilized are Coix spp., Oryza spp., Vigna spp., plants from the tribe Triticeae, roots from some plants of Zingiberaceae, and other species of roots and tubers.More than 457 grains were retrieved from the 13 stone tools.The fact that Coix spp.were found in all stone tools suggests that these species were a major food source during the Neolithic era.In addition, 28 starch grains of Oryza spp.were found in 8 stone tools.The analysis also revealed that not only seeds of Gramineae but also those of Leguminosae, Zingiberaceae and other species of roots and tubers are among the plants utilized in the four Fanchengdui culture sites.These results indicate that ancient plant utilization was rather diverse, and this study elucidates the prehistoric agricultural systems of South China.

Starch grain analysis reveals function of grinding stone tools at Shangzhai site, Beijing

Prehistoric groundstone tools including slabs (metate, mo-pan) and mullers (mano, mo-bang) are often considered to be tools that were used to process cereals in ancient China. Most archaeologists believe that groundstone tools are indicators of an agrarian economy. This study employed starch grain analysis to examine a slab and a muller excavated from the Shangzhai Site (7500-7000 cal a BP), Beijing. Identifiable starch grains recovered from the stone tools were classified into 9 genera and 12 species, most of which were from acorns and foxtail millets. Remains from the oak species Q. mongolicus, Q. acuttssima, and Q. dentate were identified as well as a few starch grains from broomcorn (Panicum miliaseum) and bean (Vigna sp.). Other starch grains were from unidentifiable roots and grasses. A variety of starch grains indicates that the grinding stone tools were used to process not only cereals, but also other seeds or roots that had to be ground or husked, thus bringing into question the aforementioned cereal hypothesis. Because the numbers of starch grains from nuts and millets were so large, both gathering and cultivation might have been important economic patterns before 7000 years ago in Beijing area. Moreover, the starch remains are derived from plants that indicate that the paleoclimate of Beijing was wetter and warmer than today’s.

Starch grain analysis reveals ancient diet at Kuahuqiao site,Zhejiang Province

Charred residues adhering to sherds of ceramic cooking vessels,pots (Fu),excavated from the Kuahuqiao site (8000-7000 cal a BP) in Zhejiang Province were examined using the method of starch grain analysis.Ancient starch grains were recovered from charred residues and were classified into 8 genera.Remains from rice (Oryza spp.),job's-tears (Coix chinesis T.),bean (Vigna spp.),acorn (Quercus spp.) as well as possibly buckeye tree (Aesculus chinensis B.) were identified.Other starch grains from unidentified plants were also recovered.Tracheids with bordered pits from softwood fibers were also found,indicating that some food might have been processed with wooden tools.The range of starch grains in the charred residues adhering to the ceramic pots reveals the diversity of ancient plant foods at the Kuahuqiao site,Zhejiang Province.

Starch grains from dental calculus reveal ancient plant foodstuffs at Chenqimogou site, Gansu Province

Chenqimogou site, located at the south bank of Tao River, is comprised of a large group of graves dated to ~4000 a BP. For its large scale, unique mortuary system, and abundant of typical artifacts, the site was named one of 'Top Ten Archaeological Discoveries of 2008 in China'. Many intact human skeletons have been excavated from the graves. Three teeth from two adult skeletons excavated from graves M187 and M194 were examined. Forty-eight starch grains were retrieved from dental calculus of three teeth. Six of those starch grains could not be identified because of damage. The others were classified into seven groups. Most of them were from wheat (Triticum aestivum) and/or barley (Hordeum vulgare). Remains possibly from foxtail millet (Setaria italica), buckwheat (Fagopyrum esculentum), gingkgo (Ginkgo biloba), acorn (Quercus spp.), bean, roots or tubers were identified. Ancient starch grains from dental calculus indicate that human foodstuffs primarily sourced from wheat, buckwheat, and foxtail millet. Acorn, beans, tubers or roots were supplements. A variety of starch grains retrieved from dental calculus revealed that diverse crops were cultivated in the Chenqimogou site 4000 years ago, and both dry-land farming and gathering were engaged.

Changes in wheat starch grains using different cooking methods: Insights into ancient food processing techniques

We investigate the morphological changes in starch grains from wheat(Triticum aestivum) using different cooking methods(boiling, steaming, frying, and baking). We compare the cooked starch grains with starch grains from ancient wheat flour cakes(Astana Cemetery, Turpan Basin, Xinjiang, China) to determine the cooking techniques used by people in Xinjiang 1200 years ago. Heat and water content affect starch grains when different cooking methods are used. Boiling and steaming results in the collapse of wheat starch grains accompanied by extreme swelling, curved granules, pasting, almost full gelatinization, a distinct extinction cross and vague granule outlines. Frying and baking cause less swelling, fewer curved granules, less pasting and only partial gelatinization of wheat starch grains, but the extinction lines are still distinct and the outlines of granules relatively clear. The pale brown substances on the starch grains make starch from baked-wheat products distinct from those cooked using other methods.

Starch Digestibility and Physicochemical and Cooking Properties of Irradiated Rice Grains

This study evaluated the starch digestibility, physicochemical properties and cooking characteristics of polished rice（varieties IRGA417 and IAC202） subjected to the doses of 0（as the control）, 1, 2 and 5 k Gy of gamma radiation. The highest dose decreased the apparent amylose content, peak viscosity, water absorption and volume expansion. Irradiation increased the solid loss by 119% and 187% for IAC202 and IRGA417, respectively, when comparing the higher dose with the control. For IAC202, irradiation decreased the rapidly digestible starch and increased the slowly digestible starch（SDS） and resistant starch（RS）. IRGA417 showed an elevation of SDS and a reduction in RS. And 1 k Gy dose of gamma radiation generated the highest level of RS for both the two varieties and presented the smallest changes in other physicochemical and cooking properties.

Changes in Activities of the Key Enzymes Related to Starch Synthesis in Rice Grains During Grain Filling and Their Relationships with the Filling Rate and Cooking Quality

With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during grain filling, and theirrelationships with the filling rate, gel consistency (GC), alkali spreading value (ASV) and amylose content (AC) werestudied. The results showed that changes in activities of ADPGPase, SSase and Q-enzyme exhibited a single peak duringgrain filling, and the time of the activity peaks for the former two enzymes was earlier than that of the maximum grain-fillingrate (Tmax), and the time reaching the peak for Q-enzyme was synchronous with Tmax. The activities at early grain fillingstage, and the mean and maximum activities of each enzyme during grain filling period were positively and significantly orvery significantly correlated with the mean and maximum grain filling rate and starch content (mg grain-1) in the grains.Activities of ADPGPase at all grain filling stages and those of Q-enzyme at the early and mid filling stages were notsignificantly correlated the cooking quality (GC, ASV and AC). SSase activities at the early filling stage were significantlyand negatively correlated with GC and ASV, and positively correlated with AC. Activities of SSase at mid and late grainfilling stages and Q-enzyme at the late filling stage were significantly and positively correlated with GC and ASV, andnegatively correlated with AC. Spraying zeatin or abscisic acid at early grain filling stage could obviously regulate theactivities of ADPGPase, SSase and Q-enzyme in the grains.

Effects of exogenous ABA application on post-anthesis dry matter redistribution and grain starch accumulation of winter wheat with different staygreen characteristics

The objective of this study was to investigate whether and how exogenous abscisic acid(ABA)is involved in mediating starch accumulation in the grain and redistribution of carbohydrates during grain filling of two wheat cultivars with different staygreen characteristics.At blooming stage,plants of Wennong 6(a staygreen cultivar)and Jimai 20(control)were sprayed with10 mg L-1abscisic acid(ABA)for 3 days.The application of ABA significantly(P<0.05)increased grain filling rate,starch accumulation rate and content,remobilization of dry matters to kernels,and 1000-grain weight of the two cultivars.Exogenous ABA markedly(P<0.05)increased grain yield at maturity,and Wennong 6 and Jiami 20 showed 14.14%and 4.86%higher compared yield than the control.Dry matter accumulation after anthesis of Wennong 6 was also significantly(P<0.05)influenced by exogenous ABA,whereas that of Jimai 20 was unchanged.Application of ABA increased endogenous zeatin riboside(ZR)content 7 days after anthesis(DAA),and spraying ABA significantly increased endogenous indole-3-acetic acid(IAA)and ABA contents from 7 to 21 DAA and decreased gibberellin(GA3)content at 14 DAA,but increased GA3content from 21 to 35 DAA.The results suggested that increased yield of staygreen was due to greater starch assimilation owing to a higher filling rate and longer grain-filling duration.

Relationship Between Variation in Activities of Key Enzymes Related to Starch Synthesis During Grain Filling Period and Quality of Eating and Cooking in Rice

Four japonica rice varieties with significant differences in quality of eating and cooking were used in the experiment. The varieties showed differences in amylose and amylopectin contents at different grain filling stages, which were attributed to the accumulative speed of starch at different grain filling stages. During grain filling period, the varieties had no difference in the time when the activities of ADPglocose pyrophosphorylase （AGPP） and soluble starch synthesis （SSS） reached a maximum, but had difference in the time when the activity of starch branching enzyme （SBE） reached a maximum, in which the inferior quality varieties were earlier than the high quality ones, and high quality varieties still kept high enzyme activities at the late stage of grain filling. The correlation and correlative degree between AGPP, SSS, SBE and amylose content, amylopectin content, taste meter value, and RVA properties varied with the different stages of grain filling. The correlation between SSS activity and taste meter value was not significant during the whole period of grain filling, but the activities of AGPP and SBE had significant or highly significant correlation with taste meter value. It was helpful for improving quality of eating and cooking of japonica rice to use the materials with low enzyme activity at the early stage of grain filling or high enzyme activity at the late stage as parents.

Methodological impact of starch determination on starch content and ileal digestibility of starch in grain legumes for growing pigs

Background： Grain legumes represent a valuable energy source in pig diets due to their high starch content. The present study was conducted to determine the content and apparent ileal digestibility（AID） of starch in different grain legume cultivars for pigs by means of both a polarimetric and enzymatic method for starch determination.Methods： Three experiments were conducted with six barrows each which were fitted with ileal T-cannulas. In total, 18 diets including six different cultivars of faba beans（Vicia faba L.） and peas（Pisum sativum L.）, five different cultivars of lupins（Lupinus luteus L., Lupinus angustifolius L.）, and one diet with a soybean meal（SBM） were fed.Results： The starch content of faba beans and peas was greater（P ＆lt; 0.05） when determined polarimetrically than enzymatically（438 vs. 345 g/kg dry matter（DM） in faba beans and 509 vs. 390 g/kg DM in peas, respectively）.Considerable lower starch contents were obtained in lupins and SBM, with 82 and 48 g/kg DM（analyzed polarimetrically） and ＆lt;1.1 and 3 g/kg DM（analyzed enzymatically）, respectively. Mean values for contents of neutral detergent fiber（NDF） and acid detergent fiber（ADF） in grain legumes ranged from 111 and 79 g/kg DM in peas to248 and 207 g/kg DM in lupins, respectively. Contents of condensed tannins in the colored flowered faba bean cultivars ranged from 2.1 to 7.4 g/kg DM. The AID of starch was greater（P ＆lt; 0.05） in pea than in faba bean cultivars,and using the polarimetric starch determination method resulted in greater（P ＆lt; 0.05） digestibility values than using enzymatic starch analysis（84 vs. 80% in faba beans and 86 vs. 83% in peas）. Moreover, AID of starch differed（P ＆lt; 0.05）within pea cultivars and starch digestibility in faba beans decreased linearly（P ＆lt; 0.05） as the content of condensed tannins increased. However, there was no relationship between contents of NDF and ADF and AID of starch in pea and faba bean cultivars.Conclusion： Both contents and AID of starch in grain legumes can vary as influenced by the analytical method used for starch determination. Generally, starch digestibility is greater when measured by polarimetric rather than enzymatic methods.

Effect of Temperature at Grain Filling Stage on Activities of Key Enzymes Related to Starch Synthesis and Grain Quality of Rice

Three japonica rice varieties with different cooking and eating quality were grown at high temperature in the greenhouse and natural field. Effects of temperature at the grain filling stage on these varieties were investigated in terms of the activities of key enzymes related to starch synthesis and cooking and eating quality of rice grain. The high temperature at the grain filling stage increased protein content, and decreased amylose content and taste meter value of rice; inferior grain quality varieties showed a greater magnitude of the increase or decrease than the superior ones. Reaction of rapid visco analyser profiles to the temperature varied with rice varieties. The activities of adenosine diphosphoglucose pyrophosphoryiase （AGPP）, soluble starch synthase （SSS） and starch branching enzyme （SBE） gradually increased to a peak value, and thereafter declined as grain filling progressed. Enzyme activities in different varieties differed in a same filling stage, and also in the time when the enzyme activity reached a maximum. AGPP and SSS were insensitive to the environmental temperature, but SBE was comparatively sensitive to the temperature, and its activity declined when temperature was too high or too low.

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.

糯小麦“山农糯麦1号”籽粒及淀粉品质分析

为更好地了解糯小麦的品种特性,以山东省第一个审定的高产糯小麦“山农糯麦1号”为材料,研究其籽粒和淀粉特性。结果发现:该品种几乎不含直链淀粉(仅0.1%),较普通小麦具有较高的蛋白质含量(16.4%)和面粉白度(81.2%)。扫描电镜观察淀粉粒度分布不均匀,A型淀粉颗粒较多。快速粘度分析(RVA)测定表明淀粉具有较低的糊化温度,较短的糊化时间,较低的峰值黏度、最终粘度和回生值。加工时面团吸水率明显较高,形成时间大于稳定时间。这些结果将为山农糯麦1号适于用作配粉和加工食品提供参考依据。

淀粉及其改性产品对东鞍山细粒赤铁矿聚团——磁选的影响

针对东鞍山强磁选抛尾存在粒度小于20μm的微细粒铁矿物流失的问题,研究了不同种类淀粉及其改性产品对微细粒赤铁矿的选择性聚团效果,通过团聚—磁选试验确定了适宜的团聚药剂和用量,借助偏光显微镜和红外光谱等手段检测了药剂与赤铁矿和石英作用前后的形貌特征,最后通过研究高分子药剂的作用机理,论述了药剂的选择性和团聚效果。结果表明:在药剂用量为200 g/t时,交联玉米淀粉的选矿指标优于其他几种药剂,团聚药剂的加入能实现微细粒赤铁矿的选择性聚团,使铁精矿回收率提高2.13~3.94个百分点,选矿效率提高2.77~3.46个百分点,但由于赤铁矿被团聚后呈不规则絮状,在较大的聚团中会夹杂少量石英,导致磁选精矿铁品位略微降低。

Fe元素对半夏试管珠芽形成及试管苗生长的影响

为选出培养半夏试管珠芽的适宜Fe^(2+)浓度,该研究通过梯度改变1/2MS基本培养基中Fe^(2+)浓度,依据试管珠芽的形成时间、诱导率,试管苗地上、地下形态指标,试管珠芽中淀粉粒数量与分布,叶片叶绿素含量及试管珠芽有效成分含量等指标,得出试验结果为9.2×10^(-5)mol·L^(-1)浓度下各项指标最佳。此外,还发现Fe缺素下无法形成完整试管珠芽,说明Fe是半夏试管珠芽形成过程中必不可少的微量元素,但同时浓度不宜过高,因高浓度Fe^(2+)下,形成的试管珠芽极小且后续无法正常萌发成苗。

氮素穗肥对杂交籼稻籽粒灌浆影响及其与淀粉合成关键酶活性间关系

【目的】为明确氮素穗肥对杂交稻籽粒灌浆和淀粉合成关键酶活性的影响。【方法】选用两个直链淀粉含量差异较大的杂交稻品种锦优1319(高直链淀粉)和蓉优702(低直链淀粉),在不同的氮素穗肥处理下(设0、60、90和120 kg/hm^(2)4个纯氮水平,分别用CK、N1、N2、N3表示)研究氮素穗肥水平对籽粒灌浆和淀粉合成关键酶活性的影响。【结果】不同穗肥处理下杂交稻籽粒灌浆特性差异显著,且不同类型品种表现各异,其中氮素穗肥的施用显著降低了稻米的直链淀粉含量。锦优1319的Gmax和Gmean随氮素穗肥水平的变化均表现为N2>CK>N1>N3,而蓉优702则表现为N3>N2>CK>N1;施用氮素穗肥显著增加了花后5~25 d籽粒腺苷二磷酸焦磷酸化酶(ADPG)和淀粉分支酶(DBE)的活性,降低了花后5~15 d籽粒GBSS活性,降低了花后5~25 d籽粒淀粉合成酶(SSS)和SBE活性。【结论】高直链淀粉品种锦优1319籽粒灌浆的最佳氮素穗肥施用量低于低直链淀粉品种蓉优702:其中锦优1319的最佳氮素穗肥施用量为90 kg/hm^(2),蓉优702为120 kg/hm^(2)。施用氮素穗肥显著降低了GBSS、SSS的活性,加之SBE活性下降,DBE活性提高,最终降低稻米直链淀粉含量。本研究条件下,籽粒ADPG活性未对稻米直链淀粉含量产生显著影响。

施磷量对不同耐低磷型水稻品质及淀粉合成酶活性的影响

适宜磷肥用量对水稻品质具有一定影响。为明确施磷量对不同耐低磷型水稻品质及其强、弱势粒淀粉合成相关酶活性的影响,以‘连粳7号’(弱耐低磷)和‘甬优2640’(强耐低磷)为供试水稻品种进行盆栽试验,设置4个磷肥施用量(按P_(2)O_(5)计):0 kg·hm^(-2)(P0)、60 kg·hm^(-2)(P60)、120 kg·hm^(-2)(P120)、180 kg·hm^(-2)(P180),分析不同施磷量下稻米品质与淀粉合成酶活性之间的关系,为高品质稻米栽培提供参考。结果表明:1)与P0相比,增施磷肥改善了稻米品质。随着施磷量增加,糙米率、精米率、整精米率呈先增加后降低趋势,垩白粒率、垩白面积、垩白度、碱消值、直链淀粉含量先降低后增加。‘连粳7号’与‘甬优2640’分别在P120、P60时稻米品质最优,糙米率、精米率和整精米率分别比P0增加19.6%、25.3%、79.7%(‘连粳7号’)与17.8%、23.5%、38.4%(‘甬优2640’);‘甬优2640’稻米品质优于‘连粳7号’。2)与P0相比,增施磷肥提高了水稻籽粒淀粉合成相关酶活性。腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)、可溶性淀粉合成酶(StSase)、蔗糖合成酶(SuSase)、淀粉分支酶(Q-酶)、三磷酸腺苷酶(ATPase)活性随施磷量增加先增加后降低。总体来看,‘连粳7号’与‘甬优2640’分别在P120、P60时淀粉合成相关酶活性最高,灌浆中期强势粒AGPase、StSase活性分别比P0增加18.4%、51.1%(‘连粳7号’)与20.0%、51.5%(‘甬优2640’);‘甬优2640’籽粒酶活性高于‘连粳7号’。3)不同耐低磷型品种淀粉合成相关酶活性与蛋白质含量、直链淀粉含量相关性不同。淀粉合成相关酶显著或极显著影响‘连粳7号’蛋白质含量,对直链淀粉含量影响较小;淀粉合成相关酶活性显著或极显著影响‘甬优2640’直链淀粉含量,对蛋白质含量影响较小。‘连粳7号’与‘甬优2640’分别在P120、P60处理下能够提高强弱势粒中淀粉合成相关酶活性,促进籽粒中淀粉的合成与积累,有利于水稻品质改善。