Research on the ultrafast fluorescence property of thylakoid membranes of the wild-type and mutant rice

A high yielding rice variety mutant (Oryza sativa L., Zhenhui 249) with low chlorophyll b (Chl b) has been discovered in natural fields. It has a quality character controlled by a pair of recessive genes (nuclear gene). The partial loss of Chl b in content affects the efficiency of light harvest in a light harvest complex (LHC), thus producing the difference of the exciting energy transfer and the efficiency of photochemistry conversion between the mutant and wild-type rice in photosynthetic unit. The efficiency of utilizing light energy is higher in the mutant than that in the wild-type rice relatively. For further discussion of the above-mentioned difference and learning about the mechanism of the increase in the photochemical efficiency of the mutant, the pico-second resolution fluorescence spectrum measurement with delay-frame-scanning single photon counting technique is adopted. Thylakoid membranes of the mutant and the wild-type rice are excited by an Ar^+ laser with a pulse width of 120 ps, repetition rate of 4 MHz and wavelength of 514 nm. Compared with the time and spectrum property of exciting fluorescence, conclusions of those ultrafast dynamic experiments are: 1) The speeds of the exciting energy transferred in photo-system I are faster than that in photo-system II in both samples. 2) The speeds of the exciting energy transfer of mutant sample are faster than those of the wild-type. This might be one of the major reasons why the efficiency of photosynthesis is higher in mutant than that in the wild-type rice.     

Cloning of Promoter of Chinese Bean GRP 1.8 Gene and Characterization of Its Function in Transgenic Tobacco Plants

IntroductionVascular cells that are determined to becometracheary elements undergo a very distinct celldifferentiation.In contrast to many other types ofplant cells that can dedifferentiate and evenultimately form a new plant,cells determined tobecome tracheary elements are programmed to die.Glycine- rich proteins belong to a class ofstructural cell wall proteinsthatcontain about60 %glycine on the molar basis. Glycine- rich proteinsare localized in cell walls of bean[1] .Glycine- richprotein1…     

血透患者微量元素营养状况初步探讨

对门诊维持性血透肾衰患者进行了膳食营养调查。结果表明：（1）在临床检查中发现,血透肾衰患者面黄肌瘦,面色苍白,浮肿,疲劳;体质虚弱,四肢无力;精神不振,具有明显的营养不良的临床表现。（2）在膳食调查中发现,每人每日营养素摄入量为蛋白质41．54mg,热量5288kJ,钙104mg、铁4．86mg和锌8．86mg、硒35μg、铜2．28mg、锰2．86mg、镁76．50mg、磷448mg、钾752mg和钠1385．4mg;视黄醇当量368μg、vitarmin B10.58mg、vitamin B20.39mg、vitarnin C51mg、vitaminPP12.60mg和vitaminE0.38mg。提示血透肾衰患者蛋白质－热量营养不良,K、Na过量,而Ca、Mg、P等宏量元素和Zn、Cu、Fe、Mn、Se等微量元素和RE、vitamin B1、vitamin B2、vitamin C均未达到RDA要求。原因是主食营养不平衡。因此,建议对血透肾衰患者进食主食营养平衡米（NBR）和制订平衡食谱,开展透析日营养治疗和病人家庭营养治疗。改善血透肾衰患者微量元素营养状况。     

固相萃取-高效液相色谱法同时检测大米中12种磺酰脲类除草剂的残留

建立了固相萃取前处理净化技术-高效液相色谱（HPLC）同时检测大米中12种磺酰脲类除草剂残留的方法。采用ENVITM-18(C18)硅胶柱和ENVI-Carb(GCB)石墨化碳柱对样品进行净化、萃取,采用C8柱,以乙腈和5 mmol/L 冰乙酸混合溶剂为流动相进行梯度洗脱,在240 nm下进行检测。12种磺酰脲类除草剂在0.01~0.50 μg/g添加范围内的回收率为72.2%~106.5%,相对标准偏差为0.6%~6.4%,检出限为0.01~0.02 μg/g。     

用近红外光谱分析转基因抗虫棉根际全氮和有机质含量

随着转基因植物的普及推广,人们越来越关心其生态安全性。以转基因棉花及其对照为实验材料,借助于近红外光谱仪对转基因棉花及其对照根际土壤和非根际土壤中的全氮和有机质进行了分析测定,扫描区间为12 000～4 000 cm-1,分辨率为4 cm-1,扫描次数为64次;同时用标准方法进行对比测定。结果显示近红外检测样品的结果与标准方法结果无明显差别,说明通过扫描光谱加上数学和计算机软件分析,非常准确、方便地测定了转基因作物根际土壤中的全氮和有机质。结果显示,转基因棉花根际土壤中的全氮和有机质含量显著高于对照中的含量,分析原因主要可能与转基因抗虫棉向根际土壤分泌毒蛋白所致,毒蛋白会结合在土壤颗粒上,降解较慢,增加了全氮和有机质的含量,有机质又会增加土壤微生物的繁殖,进一步增加了土壤有机质含量。     

应用ICP-MS检测转基因大豆油中22种元素含量

随着转基因食品的推广应用,人们越来越关心其营养特性。以转基因大豆油为实验材料,借助于ICP-MS对转基因大豆油中22种元素含量进行了测定。结果显示,七种大量元素含量在0.13～12.52 μg·g-1范围内;15种微量元素在0.15～700.00 ng·g-1之间。大量元素由多到少的顺序是：Ca>Na>K>Mg>Al>P>Si;微量元素中含量最多的五种元素是Zn>Ba>Cr>Fe>Ti。结果说明市场上销售的转基因大豆油,各种营养元素含量可以达到要求,特别是Zn,Ba,Cr,Fe等微量元素含量较高。     

ICP-MS/ICP-AES法快速测定转基因棉花种子中的矿质元素和重金属含量

转基因植物生理生态已成为当前的研究热点,外源基因的导入可能会造成许多无法预料的结果。文章借助ICP-MS/ICP-AES技术对我国自己研制的转基因棉花和对照种子中的矿质元素和重金属进行了研究。结果显示,转基因棉花种子中,所测量的15种矿质元素含量有12种显著低于非转基因对照,说明转基因棉花种子吸收和累积矿质元素的能力下降;而只有镁、铁、铜含量高于对照。在测定的九种重金属(有害元素)中有七种转基因抗虫棉高于对照,特别是铝和砷的含量高出许多甚至上百倍,而铬和汞两种重金属含量明显低于对照。     

近红外光谱在转基因玉米检测识别中的应用

随着转基因食品的推广应用,人们越来越关心其食用安全性。以转基因玉米及其亲本为实验材料,借助于近红外光谱仪对转基因玉米及其亲本进行了识别分析：扫描区间为12 000～4 000 cm-1,分辨率为4 cm-1,扫描次数为64次;以三层误差反向传播算法(简称BP算法)进行数据处理。结果显示通过扫描光谱及数学和计算机软件分析,非常准确、方便地识别了转基因农产品。所以通过近红外光谱所建立的转基因BP-网络识别模型完全可用于实际应用。近红外分析还具有无污染、成本低等优点,是一种极具前景的转基因食品安全检测识别技术。     

环氧氯丙烷改性稻草

环氧氯丙烷改性稻草;稻草;环氧氯丙烷;醚化;改性     

火焰和石墨炉原子吸收光谱法对大米中金属元素含量的测定分析

采用火焰和石墨炉原子吸收光谱法对随机抽取的江西省、吉林省共五种大米中的Fe、Cu、Zn、Mn、Ca、Pb等六种金属元素进行了测定。结果表明,江西省大米中的金属元素含量均略高于吉林省前谷县达里巴乡大米,这可能与南北土壤中金属元素的分布不同有关。