高效液相色谱法测定小麦幼苗中植物生长调节剂

介绍了高效液相色谱法测定麦苗中植物生长调节剂（赤霉素ＧＡ３），３－吲哚乙酸（ＩＡＡ）的方法，用国产预处理小柱处理样品，并以甲醇：１％，冰乙酸＝１２：８８（Ｖ／Ｖ）为流动相，色谱柱为ＺｏｒｂａｘＣ１８，在２１０ｎｍ紫外检测。     

Computational gibberellin‐binding channel discovery unraveling the unexpected perception mechanism of hormone signal by gibberellin receptor

Gibberellins (GAs) are phytohormones essential for many developmental processes in plants. In this work, fundamental mechanism of hormone perception by receptor GID1 has been studied by performing computational simulations, revealing a new GA‐binding channel of GID1 and a novel hormone perception mechanism involving only one conformational state of GID1. The novel hormone perception mechanism demonstrated here is remarkably different from the previously proposed/speculated mechanism [Murase et al., Nature 2008 , 456, 459] involving two conformational states (“OPEN” and “CLOSED”) of GID1. According to the new perception mechanism, GA acts as a “conformational stabilizer,” rather than the previously speculated “allosteric inducer,” to induce the recognition of protein DELLA by GID1. The novel mechanistic insights obtained in this study provide a new starting point for further studies on the detailed molecular mechanisms of GID1 interacting with DELLA and various hormones and for mechanism‐based rational design of novel, potent growth regulators that target crops and ornamental plants. © 2013 Wiley Periodicals, Inc.     

高效液相色谱-串联质谱法测定葡萄中的吡效隆和赤霉素

采用高效液相色谱-串联质谱法（HPLC-MS/MS）建立了葡萄果实中吡效隆（CPPU）和赤霉素（GA3）两种植物生长调节剂残留量的定性定量分析方法。样品用0.5%甲酸水溶液和乙腈（体积比4:1）混合溶剂提取,经Strata-X固相萃取净化,使用Agilent SB-C18 色谱柱（50mm×2.1mm,1.8μm）,以0.5%甲酸水溶液-乙腈为流动相,流量0.3mL/min,采用电喷雾离子化源（ESI）多反应监测（MRM）模式下HPLC-MS/MS检测。在最佳检测条件下,得到吡效隆和赤霉素在2.0～100.0μg/L检测范围内线性关系良好,相关系数大于0.999;检出限(LOD)分别为0.3μg/L、0.5μg/L,定量限(LOQ)分别为1.0μg/L、2.0μg/L,回收率和精密度均能达到要求,表明该法准确,可用于葡萄中吡效隆和赤霉素残留量测定。     

Gibberellin Increases the Bud Yield and Theanine Accumulation in Camellia sinensis (L.) Kuntze

Tea (Camellia sinensis) is one of the most important cash crops in the world. Theanine, as an important amino acid component in tea, is a key quality index for excellent tea quality and high economic value. People increase theanine accumulation in tea mainly through the application of nitrogen fertilizer, shading and pruning. However, these methods are not effective. In this study, we treated tea buds with a 100 μM solution of GA₃ containing 1‰ tween-20, investigated the effects of GA₃ on theanine accumulation, bud yield, chlorophyll fluorescence parameters and expression level of theanine biosynthesis pathway genes in tea plant by qPCR, LC-MS/MS etc. Results showed that change trends of theanine and GA₃ was extremely positively correlated with each other. Exogenous GA₃ upregulated the expression level of theanine biosynthesis pathway genes, caused an increase of theanine content (mg·g^-1) by 27% in tea leaves compared with Mock, and accelerated the germination of buds and elongation of shoots, which lead to a significant increase of tea yield by 56% (w/w). Moreover, the decrease of chlorophyll contents, photochemical quenching coefficient (qP) and relative electron transport rate (rETR) under GA₃ treatment suggested that GA₃ reduced photosynthesis in the tender tea leaves, indicating that the decline of carbon assimilation in tea plants was conducive to the nitrogen metabolism, and it was beneficial to the accumulation of theanine. This study provided a new technical and theoretical support for the precise control of tea quality components and phenophase.     

New C20-gibberellin diterpene from the leaves of Schefflera sessiliflora De P. V.

From the leaves of Schefflera sessiliflora De P. V., one new C₂₀-gibberellin diterpene 2β,12β-dihydroxygibberellin (12β-hydroxy-GA₁₁₀ or 2β-hydroxy-GA₁₁₂) (1), together with three known compounds, trans-tiliroside (2), kaempferol 3-O-β-d-glucuronopyranoside (3), 5-p-trans-coumaroylquinic acid (4), was isolated for the first time from the genus Schefflera by various chromatography methods. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and comparison with previous reported data. The α-glucosidase inhibitory activity of all compounds was measured. The isolates (2, 3) showed better α-glucosidase inhibitory activity (IC₅₀ = 134.60, 147.10 μM, respectively) than the standard drug acarbose (IC₅₀ = 214.50 μM).     

测定水中硅的新还原剂——赤霉素－葡萄糖－二氯化锡混合液

采用赤霉素－葡萄糖－二氯化锡混合液作为钼蓝法中的新还原剂。在 0.2 mol/L HNO3介质中 , 赤霉素－葡萄糖－二氯化锡混合物与硅杂多酸反应生成杂多蓝。λ max=801 nm, 表观摩尔吸光系数为 1.28× 104 L· mol－ 1· cm－ 1, 硅含量在 0.1～ 4 mg/L范围内符合朗伯－比尔定律。以赤霉素－葡萄糖－二氯化锡混合液作还原剂,还原速度快,产物稳定性好,操作简便,结果令人满意。     

高效液相色谱法测定谷子幼苗中的GA_1和GA_3

建立了同时测定谷子幼苗中赤霉素Ａ１（ＧＡ１）和赤霉素Ａ３（ＧＡ３）的高效液相色谱（ＨＰＬＣ）方法。采用ＯＤＳ Ｃ１８色谱柱,以磷酸盐缓冲液和甲醇为流动相,ＧＡ１和ＧＡ３在１０ｍｉｎ内获得良好分离。利用该方法对谷子的两个正常栽培品种及其矮秆突变体的幼苗进行了测定。测定结果表明,谷子幼苗中同时含有ＧＡ１和ＧＡ３两种活性赤霉素,它们各自的质量比是影响谷子株高的重要因素。     

赤霉素-葡萄糖-二氯化锡混合液测定水中无机磷的应用研究

引入赤霉素 -葡萄糖 -二氯化锡混合液作为钼蓝法的新显色剂 .在 1.0 mol/ L HNO3介质和有机相中 ,赤霉素 -葡萄糖 -二氯化锡混合物与无机磷杂多酸反应生成杂多蓝 ,经萃取分离测定有机相 ,λmax=690 nm,表观摩尔吸光系数为 2 .54× 10 4 L· mol-1· cm-1.PO3-4 浓度范围在 0 .1～ 4 mg/ L符合朗伯 -比耳定律 .赤霉素 -葡萄糖 -二氯化锡混合还原剂还原速度快 ,产物稳定性好 ,操作简便 ,结果令人满意     

SPE-GC-MS选择离子法直接测定果品中赤霉素残留量

建立了固相萃取-气相色谱-质谱选择离子(SPE-GC-MS-SIM)直接分析果品中赤霉素 (GA3)残留量的方法。研究了样品在C18萃取柱上的保留行为。采用HP-1的色谱柱,直接进样 GC-MS测定,选择离子监测(SIM)克服了样品基体干扰,灵敏度较全谱扫描高。线性范围为0．11 -3．3×103mg·L-1,检出限为0．11 mg·kg-1,回收率为75．3-101．3％,RSD小于4．75％。