Lipids of seven cereal grains

Grain samples of representative varieties of barley, corn, oats, rye, sorghum, triticale, and wheat grown commercially in the north central US were analyzed. Chemical constituents of the varieties studied are presented to provide an overview of their characteristics. Lipids of the milled grain samples were solvent extracted, classified by silicic acid column chromatography, and separated by thin layer chromatography. Fatty acid composition of the total lipid was determined by gas liquid chromatography and the fatty acid content was determined by saponification and extraction. Total lipid content of the grains ranged from 2.3% for ‘Polk’ wheat to 6.6% for ‘Chief’ oats. Lipid composition varied considerably. The row crops, corn and sorghum, have a high neutral lipid and low glycolipid content. The small grain varieties have a more balanced distribution among neutral lipids, glycolipids, and phospholipids. Fatty acid composition of the total lipid was similar for all grains. Minor qualitative differences were noted among the lipid classes of the 7 cereals.     

Tocol levels in milling fractions of some cereal grains and soybean

Tocol levels in the milling fractions of rice, barley, corn, wheat, and soybeans were analyzed by HPLC with a fluorescence detector. Among all milling fractions tested in this study, rice germ had the highest total tocol levels. In the four milling fractions of barley, except pearling flour, all eight tocol isomers were detected, and they were more uniformly distributed than in any other cereal grains measured in this study. The total tocol and α-tocopherol levels of wheat germ were significantly (P<0.05) higher than the other wheat milling fractions. A significantly (P<0.05) higher proportion of γ-tocopherol was obtained from corn germ (71.5%) and endosperm (50.3%) than from corn hulls. Only four tocol isomers (α-, β-, γ-, and δ-tocopherol) were detected in soybean milling fractions; no tocotrienol isomers were detected. The δ-tocopherol level of soybean endosperm, although minor, was significantly higher than those in milling fractions of other cereal grains in this study.     

Batch and continuous spouted bed drying of cereal grains: The thermal equilibrium model

A complete set of equations with no adjustable parameters are written for numerically predicting the variation of grain temperature and moisture content with time for batch drying of well mixed deep beds of three cereal grains, as well as the exit grain and air moisture contents and temperatures for continuous drying. Unlike previous studies, the surface moisture content of the grains is not assumed constant. Agreement with both batch and continuous spouted bed drying data from the literature is good, in the continuous case especially when the assumed exit age distribution of the isothermal bed solids is specific to spouting.     

Large granules,nests or bands: Methods of increasing efficiency of fall-applied urea for small cereal grains in North America

In North America where the climate is cool enough only one crop is grown yearly, N fertilizers are sometimes applied in the previous fall rather than in the spring for fall- or spring-sown cereal grains. However, in areas where snow accumulates in winter, fall application of N fertilizers is generally inferior to spring application. Substantial nitrification takes place in winter and subsequent N loss occurs primarily in early spring by denitrification after the snow melt. Immobilization of N is also greater with fall- than spring-applied N fertilizers. Nitrogen is more efficiently retained in the soil as NH₄ and thus more effectively used by plants if formation of nitrite (NO₂) and NO₃ is reduced or prevented by inhibiting nitrification. The nitrification is reduced when urea is placed in bands, because of high pH, ammonia concentration and osmotic pressure in the soil. The rate of nitrification is further reduced when urea is placed in widely-spaced nests (a number of urea prills placed together at a point below the soil surface) or as large urea granules (LUG) by reducing contact between the nitrifying bacteria and the NH₄ released upon urea hydrolysis. A further reduction in nitrification from LUG can be obtained by addition of chemical nitrification inhibitors (such as dicyandiamide (DCD)) to LUG. The concentration of a chemical inhibitor required to suppress nitrification decreases with increasing granule size. The small soil-fertilizer interaction zone with placement of urea in nests or as LUG also reduces immobilization of fertilizer N, especially in soils amended with crop residues. The efficiency of fall-applied N is improved greatly by placing urea in nests or as LUG for small cereal grains. Yields of spring-sown barley from nests of urea or LUG applied in the fall are close to those obtained with spring-applied urea prills incorporated into the soil. Delaying urea application until close to freeze-up is also improved the efficiency of fall-applied N. This increased effectiveness of urea nests or LUG is due to slower nitrification, lower N loss over the winter by denitrification, and reduced immobilization of applied N. Fall application of LUG containing low rates of DCD slows nitrification, reduces over-winter N loss, and causes further improvement in yield and N uptake of winter wheat compared to urea as LUG alone in experiments in Ontario; in other experiments in Alberta there is no yield advantage from using a nitrification inhibitor with LUG for barley. Placement of LUG or nests of urea in soil is an agronomically sound practice for reducing N losses. This practice can eliminate or reduce the amount of nitrification inhibitor necessary to improve the efficiency of fall-applied urea where losses of mineral N are a problem. The optimum size of urea nest or LUG, and optimum combination of LUG and an efficient nitrification inhibitor need to be determined for different crops under different agroclimatic conditions. The soil (texture, CEC, N status), plant (winter or spring crop, crop geometry, crop growth duration and cultivar) and climatic (temperature, amount and distribution of precipitation) factors should be taken into account during field evaluation of LUG. There is a need to conduct region-specific basic research to understand mechanisms and magnitudes of N transformations and N losses in a given ecosystem. Prediction of nitrification from LUG or urea nests in various environments is needed. In nitrification inhibition studies with LUG and chemical nitrification inhibitors, measurements of nitrifier activity will be useful. Finally, there is need for development of applicators for mechanical placement of LUG or urea prills in widely-spaced nests in soil.     

Application of wide-line NMR to analysis of cereal products and fats and oils

The principal areas of interest to cereal and oil chemists of wide-line NMR have been reviewed. It provides a rapid method for moisture in cereals where a large number of analyses are required. In the field of plant breeding and genetics of oil seed it provides a non-destructive means of selecting seeds for test and evaluating the seeds grown. In the area of fats, oils and shortenings it provides a rapid and accurate means of measuring the solids content over a wide range of temperatures and can be applied to a finished product as is, under selected conditions. Presented at the AOCS-AACC Joint Meeting, Washington, D.C., April, 1968.     

Solvent extraction of corn oil from distillers grains

A process has been developed for extracting the corn oil from distillers’ grains rather than the incoming corn. Yields by various methods of recovery are considered. Solvent extraction by the use of low boiling petroleum naphthas was adopted. Pilot unit extraction and refining was followed by oil acceptance by refiners. Feeding tests showed the extracted grains to be superior to the original distillers’ grains. The 100-ton extraction plant expects to be in full operation the early part of 1938.     

Rapid screening method for zearalenone in corn,wheat and sorghum

A rapid and sensitive screening method has been developed for zearalenone in corn, wheat and sorghum. The method is based on minicolumn chromatography, and an analysis can be completed in ca. 10 min in most cases. Because several items used are disposable, the amount of cleanup is reduced and the cost per determination is maintained at a low level.     

玉米赤霉烯酮单克隆抗体的制备及鉴定

采用玉米赤霉烯酮(ZEN)与羧甲基羟胺半盐酸盐在吡啶中反应,生成玉米赤霉烯酮肟(ZENO),用活性酯法将ZENO与牛血清白蛋白(BSA)的氨基相连合成ZEN人工抗原;并进行了紫外吸收鉴定;以合成的BSA偶联物(ZEN-BSA)为免疫抗原,免疫Balb/c小鼠,经细胞融合,采用非竞争/竞争ELISA两步筛选法获得能够稳定分泌抗体的杂交瘤细胞株1C7.抗体1C7灵敏度(IC50)达0.61μg/L,与T-2毒素、呕吐毒素(DON)、黄曲霉毒素(AFT)的交叉反应率均＜0.1％.本研究为研发粮油产品中玉米赤霉烯酮特异性免疫分析技术及产品奠定了重要基础.     

Toxicity of cereal protein—Derived peptides for in vitro developing intestine from rat fetus

This paper describes work that shows that the PTC digest of gliadins extracted from hexaploid wheat flour have the same toxic activity of the PTC digest of gliadins extracted from hexaploid wheat gluten. Moreover, not all wheat species apparently contain the toxic components, thus suggesting that durum wheat foods may present, as compared to soft wheat foods, a lower risk for human health under particular circumstances. Similar considerations seem to apply to other cereal genera that seem to differ with respect to the presence and/or content of toxic peptides. Further experiments to test such a working hypothesis are now being made.     

脱氧雪腐镰刀菌烯醇免疫分析核心试剂特异性单克隆抗体的研制与特性研究

采用1,1’-羰基二咪唑(CDI)活化法成功将脱氧雪腐镰刀菌烯醇分子上C-3和C-15位羟基与载体蛋白赖氨酸的氨基共价偶联得到免疫原DON-BSA和包被原DON-OVA,并用三硝基苯磺酸法对合成结果进行鉴定。以人工抗原免疫Balb/c小鼠,取小鼠脾细胞与SP2/O鼠骨髓瘤细胞融合,经筛选和多次亚克隆,得到了1株能稳定分泌脱氧雪腐镰刀菌烯醇抗体的单克隆细胞株1D5,并制备单克隆抗体腹水。经检测该抗体亚型为IgG1,亲和力常数Ka为8.33×107L/mol,交叉反应的试验结果显示该抗体与其他真菌毒素无交叉反应率,稳定性良好,为粮油食品中脱氧雪腐镰刀菌烯醇免疫快速检测技术建立及产品研发提供了关键试剂材料。     

Recent advances in detoxification strategies for zearalenone contamination in food and feed

Zearalenone (ZEN) is a widely distributed mycotoxin that frequently contaminates crops and animal feed. ZEN can cause serious health problems in livestock and humans alike, leading to great economic losses in the food industry and livestock farming. Therefore, approaches for efficient ZEN decontamination in food and feed are urgently needed. Traditional physical and chemical methods may decrease the nutritional quality of food and palatability of feed, or leading to residues and safety concerns. By contrast, biological methods for the removal or degradation of ZEN overcome these problems, especially for biological degradation by microorganisms and specific enzymes extracted from strains that can convert ZEN to less toxic or even completely harmless products. In this review, we comprehensively describe methods for ZEN degradation, focusing especially on biological strategies. Finally, emerging strategies and advice on remaining challenges in biodegradation research are also briefly discussed.     

Microstructure transition from normal to abnormal grains for BaTiO3

Quantitative characterization on the microstructure evolution during sintering of barium titanate has been conducted. The microstructure of the specimens sintered at 1320–1360 °C exhibits a typical mixture of normal and abnormal grains. The size of normal grains and abnormal grains differs by two orders of magnitude. No grain with an intermediate size is observed. A “pseudo-abnormal” region composing of many partially oriented normal grains is found instead. The formation of such pseudo-abnormal regions may help the transition from fine normal grains to coarse abnormal grains.     

Electrostatic charging during the flow of grains from a cylinder

Electrostatic charging is ubiquitous in granular processing, leading to problems of safety, jamming and unwanted material segregation. To better understand the mechanics of granular charging, we focus here on flow through a metal cylinder, where we can isolate charging regions near the cylinder walls from noncharging regions further away. We confirm that monodisperse grains charge in proportion to the area of contact between grains and the cylinder walls, and so in large cylinders, most particles remain almost uncharged. Those particles that do charge reach a plateau charge density after filling the cylinder and flowing past the walls a distance of less than one and a half centimeters. For bidisperse granular blends, the net charge produced by the mixture is dominated by the component that comes into contact with the walls of the apparatus. This is found to be caused by segregation effects as well as the coating of the larger particles by the smaller ones. We make use of these results to predict the charge generated in mass flow hoppers, and we test these predictions. Finally we examine the effect of grounding the experimental apparatus, and we find that paradoxically, grounding does not prevent charge accumulation.     

玉米赤霉烯酮抗独特型单抗的制备及特异性分析

目的制备并鉴定玉米赤霉烯酮(Zearalenone,ZEN)抗独特型单抗Ab2β-1D5。方法将ZEN单抗1G4与载体蛋白KLH偶联作为免疫原,免疫BALB/c小鼠,取免疫小鼠脾细胞,与小鼠骨髓瘤细胞SP2/0融合后,以ZEN单抗Fab片段作为包被抗原,间接ELISA法筛选阳性杂交瘤细胞。经小鼠腹腔注射杂交瘤细胞,制备腹水型单抗,并经Protein G亲和层析柱进行纯化。间接ELISA法检测ZEN抗独特型单抗的抗体效价及特异性;间接竞争ELISA法检测ZEN抗独特型单抗类型、灵敏度及其与ZEN毒素间的相关性。结果共获得6株稳定分泌ZEN抗独特型单抗的杂交瘤细胞株,腹水型抗体效价为1∶1.2×105～1∶2.0×105;6株单抗均为β型抗独特型抗体(Ab2β),其中Ab2β-1D5抗体灵敏度最高,对ZEN的IC50值达10.09 ng/ml,其与ZEN毒素呈线性相关(r=0.990);ZEN抗独特型单抗与莱克多巴胺、重金属铅、铬及虾过敏原单抗均无交叉反应,特异性良好。结论已成功制备玉米赤霉烯酮抗独特型单抗,该抗体与ZEN间存在"内影像"关系,可以替代ZEN毒素标准品,用于建立ZEN的无毒免疫学检测技术。     

Nitrogen loss from different tillage systems and the effect on cereal grain yield

Grain yield, nitrogen (N) assimilation, ammonia (NH₃) volatilization, denitrification and fertilizer N distribution were examined in three commercially grown cereal crops; two were sown into conventionally tilled fields, while the third was direct drilled into an untilled field. The crops were top dressed with urea at establishment, tillering or ear initiation. Crop yield and N assimilation were measured in 16 m by 2.5 m plots receiving 0, 35, 70, 105, 140 or 175 kg N ha^–1. A mass balance micrometeorological technique was used to measure NH₃ volatilization, and other fertilizer N transformations and transfers were studied using¹⁵N labelled urea in microplots.On the conventionally tilled sites application of urea increased the grain yield of wheat from 3.9 to 5.5 t ha^–1, when averaged over the five application rates, three application times and two sites. There were no site or application time effects. However, on the direct drilled site, time of application had a significant effect on grain yield. When urea was applied at establishment, grain yield was not significantly increased and the mean yield (2.81 t ha^–1) was less than that obtained from treatments fertilized at tillering or ear initiation (4.09 and 4.0 t ha^–1, respectively). Much of the variation in grain yield at the no-till site could be ascribed to differences in NH₃ volatilization. At the no-till site, NH₃ losses were equivalent to 24, 12 and 1% of the N applied at establishment, tillering and ear initiation, respectively. Negligible volatilization of NH₃ occurred at the other sites. The surface soil at the no-till site had the highest urease activity and the soil was covered with alkaline ash resulting from stubble burning.Plant recovery of fertilizer N did not vary with application time on conventionally tilled sites (mean 62%). However, plant recovery of¹⁵N applied to the no-till site at establishment (35% of the applied N) was significantly less than that from plots where the application was delayed (45% at tillering and 55% at ear initiation, respectively). Leaching of N to below 300 mm depth was minimal (0 to 5% of the applied N). The calculated denitrification losses ranged from 1% to 14% of the applied N.The results show that the relative importance of NH₃ volatilization, leaching and denitrification varied with site and fertilization time. The importance of the various N loss mechanisms needs to be taken into account when N fertilization strategies are being developed.     

Paper coating performance of hemicellulose-rich natural polymer from distiller's grains

Coatings contribute to about 10% of the overall cost of paper production of which, the binder is the highest cost component in the formulation. In addition to costs, the binders that are currently being used are synthesized from fossil fuel feedstock raising concerns towards the sustainability of paper coatings. Furthermore, papers coated with waxes, polyolefins and other synthetic materials are difficult to recycle or compost. These challenges inherent with synthetic binders can be addressed by using renewable, plant based binders. This research focused on an abundant and underutilized source of hemicellulose based binders (DG gum) that can be extracted from distiller's dried grains. The extracted binder was compared with polyvinyl alcohol (PVA) in a coating formulation consisting of 10:1 CaCO₃ to binder formulation coated on light weight paper. Cobb test, dry and wet tensile tests, optical properties (brightness, color, opacity), water vapor transmission rate (WVTR) analysis were performed to compare the hemicellulose based binder with PVA. The results indicate water absorptivity reduction by 25% for both DG gum and PVA coatings from the base paper value. Dry tensile index was lower with higher coating weights for both coatings with similar performance. The performance on WVTR analysis for both coatings was also comparable. No significant differences in optical properties after coating were observed from that of the base paper. These results suggest that hemicellulose based binder extracted from distiller's grains has the potential to replace synthetic binders in paper coating formulations.     

Flotation of flocculated coal grains for effective enrichment

The deposition of coal slurry by means of various flocculants is experimentally studied. The flotation of flocculated coal grains is investigated. Effective conditions of coal flotation are developed.     

粮食作物对化肥的需求分析

根据相关文献资料,综述化肥在保障我国粮食安全中的作用与贡献,分析与预测实现2010年、2015年、2020年粮食总产目标所需新增化肥的数量。根据近5年来我国粮食生产中出现的问题,指出要保障我国粮食安全,除了继续发展化肥工业,增加化肥用量之外,国家应采取其他相应措施,包括稳定粮食作物的种植面积(至少应维持在11 000万hm2水平);调整粮食价格,保护农民种粮积极性;改善农田基本生产条件,推行节水灌溉技术,促进粮食均衡增产;适度提高粮食净进口份额等等。单纯依靠增加化肥的投入,实现国内粮食供需平衡,不仅代价太大(包括资源、环境和成本代价),市场和农民也不一定能够接受。     

Comparison of supercritical CO2 and hexane extraction of lipids from sorghum distillers grains

Total yields and compositions of sorghum dried distillers grains with solubles (DDGS) lipids obtained by supercritical CO₂ (SC‐CO₂) extraction were compared with those obtained by recirculated solvent extraction (RSE) with hexane. The total yield of lipids obtained by SC‐CO₂ extraction at 27.5 MPa and 70 °C was 150 g lipids/kg DDGS, while the yield obtained by RSE with hexane at 69 °C was only 85 g lipids/kg DDGS. The contents of four high‐value compounds, i.e., policosanols, phytosterols, free fatty acids (FFA) and tocols, in the lipids obtained by SC‐CO₂ extraction were 31.2, 15.6, 155.3 and 0.50 mg/g at 27.5 MPa and 70 °C, compared to 26.6, 9.6, 57.3 and 0.03 mg/g for RSE with hexane at 69 °C. The profiles of phytosterols and FFA in the sorghum DDGS lipids were relatively independent of the extraction methods and operating conditions.