Vitreosity,its stability and relationship to protein content in durum wheat

High quality requirements are set on durum wheat (Triticum durum) from semolina mills and pasta producers. For the production of semolina and pasta with good cooking quality, high grain protein content and vitreosity is required. The dependency of vitreosity on protein content as well as its stability under the influence of humidity was not well investigated up to now. We (1) compared two methods to determine vitreosity, (2) investigated the relationship between vitreosity and protein content, (3) developed a method to analyze vitreosity under humidity, and (4) examined the relationship between protein content and agronomical as well as quality traits in durum wheat. The results showed that the formation of vitreous kernels greatly depends on the protein content. To evaluate the stability of vitreosity under the influence of humidity a new method was elaborated and employed to assess the durum germplasm under study. This revealed that vitreosity of a durum wheat variety depends on the potential to form vitreous kernels but also to maintain this vitreosity under the influence of humidity. Our results further show that protein content is a central trait in durum wheat that strongly influences important traits like grain yield, vitreosity, and b-value.     

脂肪细胞定向和分化因子1(ADD1)基因的研究进展

脂肪细胞定向和分化因子1(ADD1)是重要的核转录因子。ADD1不但是脂肪分化过程中重要的转录因子,同时还可以调控与脂肪代谢相关酶基因的表达。在人类和老鼠的研究发现ADD1基因与肝脏、脾脏等非脂肪组织的脂肪沉积有明确的连锁关系。实验研究提示:ADD1基因可能是影响动物肉质性状和屠体性状的候选基因。     

月饼中安赛蜜、糖精钠、苯甲酸、山梨酸、脱氢乙酸检测方法的研究

建立了反相高效液相色谱法同时测定月饼中安赛蜜、糖精钠、苯甲酸、山梨酸、脱氢乙酸的检测技术。实验采用AQ-C18色谱柱(250 mm×4.6 mm),以0.02 mol/L的乙酸铵-甲醇(90∶10)为流动相,柱温25℃,二极管阵列检测器在波长23 0 nm处进行检测。整个分离过程在1 4m in内完成。上述5种物质的回收率为9 6.8%~1 0 2.1%,相对标准偏差小于1.21%。方法快速准确,适用于月饼的常规检测。     

不同预处理方法对饲料中微量元素含量测定的影响

[目的]研究不同预处理方法对饲料中各微量元素含量测定结果的影响,找出各元素测定的最佳预处理方法。[方法]采用干灰化法、硝酸一高氯酸湿消化法和微波消解法对样品（精料和草料）进行预处理,利用电感耦合等离子原子发射光谱仪分别测定样品中舢、ca、cu、Fe、Mn、Se和Zn等7种微量元素含量。[结果]3种预处理方法都适合对精料中Cu、Mn、Zn和草料中cu、ca含量的测定,但利用硝酸一高氯酸湿消化法处理后,测定的草料中cu和ca含量较高;微波消解法适合精料中m、ca和草料中Al、Fe、Mn、Zn含量的测定;硝酸一高氯酸消化法适合精料中Fe含量的测定。[结论]测定饲料中不同微量元素的含量应选择不同的预处理方法。     

黄河干流重要景观的确定方法研究

从自然和历史的角度,根据景观与水资源的响应关系,确定重要景观选取原则,建立了黄河干流重要景观确定的方法与步骤,并选出了黄河干流需要保护的重要景观。     

山苦茶多糖的分离和含量测定

用石油醚和95％乙醇分别浸提山苦茶叶,以去除其中脂溶性成分和单糖、低聚糖、苷类等杂质,再用水提醇沉法提取分离山苦茶多糖,最后采用Sevag试剂法和蛋白酶酶解法去除茶多糖中的蛋白质。以葡萄糖为标准,蒽酮-硫酸比色法测定山苦茶多糖含量。考察了乙醇浓度对山苦茶多糖沉淀量的影响。结果表明,采用Sevag试剂法和蛋白酶酶解法相结合去除蛋白质效果较好。采用80％乙醇浓度沉淀山苦茶多糖效果最佳,测定波长为604 nm,山苦茶中多糖含量为1.012％,方法回收率96.7％,RSD为2.45％,多糖提取液4 h内显色稳定。该试验方法测定茶多糖准确快速,显色稳定且精密度好。     

高效液相色谱法测定除草剂苄嘧磺隆含量研究

[目的]建立高效液相色谱法（HPLC）测定除草剂苄嘧磺隆含量的方法。[方法]以甲醇∶水=80∶20（V/V）为流动相,使用反相色谱柱和紫外检测器,在236 nm波长下采用HPLC测定除草剂苄.乙中的苄嘧磺隆含量。[结果]在0.5～16.0 mg/L范围内采用HPLC测定苄嘧磺隆含量的线性回归方程为y=3.565 9x＋0.657 2,R^2=0.998 6,线性关系良好。方法的添加回收率为101.4%～110.3%,标准偏差为0.168,变异系数为2.09%（n=6）,检测限为0.1 mg/L。[结论]该方法分析结果较理想,可作为苄嘧磺隆试样分析的参考方法。     

HPLC法测定六味地黄丸熊果酸的含量

[目的]用高效液相色谱（HPLC）法测定六味地黄丸（浓缩丸）的熊果酸含量,提高熊果酸的质量控制标准。[方法]色谱柱：WelchMaterials AQ-C18柱（5μm,4.6 mm×250.0 mm）;流动相：乙腈-水-磷酸（V∶V∶V=90∶10∶0.1）;柱温：25℃;流速：1.0 ml/min;检测波长为210 nm。[结果]在0.457 6~1.542 3μg/ml的线性范围内,熊果酸与峰面积呈良好的线性关系,平均回收率为99.31%,RSD值为1.09%（n=6）。[结论]高效液相色谱法灵敏、简单、快速、准确,适用于六味地黄丸（浓缩丸）熊果酸含量的测定。     

微波消解一氢化物原子荧光光谱法测定粤东地区海产品中砷的研究

[目的]建立一种测定海产品中微量砷的有效方法。[方法]采用微波消解一氢化物原子荧光光谱法测定了粤东地区海产品中砷的含量。[结果]砷在1．0-50．0μg/L范围内线性关系良好,相关系数为0．995,方法的检出限为0．02107μg/L,相对标准偏差为0．932％。部分海产品的含砷量超过国家标准,其超标原因可能与沿海地区的工业污染有关。[结论]该方法试剂用量少、污染小、简便、快速、准确,适于各类海产品中砷含量的检测。     

The investigation of the interaction between 5-Iodouracil and human serum albumin by spectroscopic and modeling methods and determination of protein by synchronous fluorescence technique

The interaction of 5-Iodouracil with human serum albumin (HSA) was investigated in aqueous solution by fluorescence quenching spectrum in combination with UV absorption spectrum and modeling method. The quenching mechanism and binding characteristics of 5-Iodouracil with HSA were obtained from the fluorescence measurement. The binding constants were calculated according to the Lineweaver-Burk equation at different temperatures. And the thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS), were calculated by thermodynamic equations. The results showed that the hydrophobic interaction played a major role in the binding of 5-Iodouracil with HSA. The binding distance was obtained according to Föster’s non-radiative energy transfer theory. The effect of some normal ions on the binding constants was discussed. Modeling method was applied to elucidate the interaction mode between 5-Iodouracil and HSA, which was agreed with the calculated result by thermodynamic method. Moreover, the synchronous fluorescence technique was successfully applied to quantify total protein in human body fluids including serum, urine, and saliva samples. The results showed that this method was stable, reliable, selective, sensitive, and practical for the determination of HSA.