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1.
<正>Gibberellin A4 is effectively separated from mixture of gibberellin A4 and its analogue gibberellin A7,in the form of its crystalline complex with N,N,N',N'-tetramethylethylenediamine.After removing the tetramethylethylenediamine from the crystal by dilute HCl,gibberellin A4 is obtained a purity of 98.1%and a yield of 72.7%.  相似文献   
2.
研究了赤霉素快速分光光度法测定,并首次应用于微量元素添加剂促进赤霉素分泌的研究.结果表明,固体发酵培养基中添加了硼酸、磷酸二氢钾、硫酸镁对促进赤霉素分泌有重要作用.结合使用作者多次筛选得到的高产赤霉素产生菌株等措施,终于研制得含量高达约15000×10-5的固体粉剂,其含量高出一般固体发酵产品的3~5倍.  相似文献   
3.
赤霉素-二氯化锡混合液在钼蓝法测定水中无机磷的应用   总被引:2,自引:0,他引:2  
应用赤霉素-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-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,最大吸收波长为 690 nm,表观摩尔吸光系数为 2.36× 104 L· mol- 1· cm- 1。质量浓度范围在 0~ 3.0 mg/L符合朗伯-比尔定律。赤霉素-二氯化锡混合还原剂还原速度快,产物稳定性好,操作简便,该法用于水中无机磷的测定,结果令人满意。  相似文献   
4.
将植物生长刺激素赤霉素引入光度分析作新显色剂,研究了赤霉素将砷、磷、硅杂多酸还原成相应杂多蓝的显色反应。在084、120、216mol/LHCl介质中,赤霉素能分别将砷、磷、硅杂多酸还原成相应的杂多蓝,其最大吸收波长分别为835、820和810nm,表观摩尔吸光系数分别为264×104、254×104和351×104L·mol-1·cm-1。线性范围分别为0~24mg/L、0~1mg/L和0~08mg/L。该法应用于钢铁中砷、磷、硅的连续测定,结果令人满意。  相似文献   
5.
An easy and mild way to construet 13-hydroxy-9,15-cyclo GA skeletons was reported and it could be used as a general protocol in the synthesis of GAs with this structure.  相似文献   
6.
The gibberellins (GAs) are diterpenoid plant growth hormones which are essential to the normal growth and development of plants1. Over one hundred GAs have been identified to date and most of these compounds are present in nature only in minute quantities. Based on their carbon skeleta, the known gibberellins can be classified into two major groups, i.e., C20-gibberellins (C20-GAs, e.g. GA12, GA53) which contain the full twenty diterpenoid carbon atoms and C19-gibberellins (C19-GAs, e.…  相似文献   
7.
An accurate and sensitive method for the simultaneous determination of gibberellic acid(GA3), gibberellin A4(GA4) and gibberellin A7(GA7) residues in tomato paste was developed by coupling solid phase extraction to high performance liquid chromatography-tandem mass spectrometry(LC-MS/MS) with electrospray ionization based stable isotope dilution analysis(SIDA). The isotope labeled internal standard can compensate for the losses during the extraction and cleanup steps and for discrimination due to ion suppression. After extraction from methanol, hydrophile lipophilic balance(HLB) solid phase extraction(SPE) column was tested for the capacity of the cleanup of the tomato paste in compared with C18 SPE column which is the common way to the detection of GAs, and the former gained better result. Spiked experiments were performed in the non-contaminated tomato pastes and the recoveries of GA3, GA4 and GA7 were 42.6%―75.0% in external standard method(ESM) and 91.1%―103.8% in internal standard method(ISM) respectively. The validities of this method were investigated and good analytical performance for the three GAs was obtained, including low limits of method detection(2 ng/g for GA3 and GA4, 0.3 ng/g for GA7), excellent linear dynamic ranges(5―500 ng/g for GA3 and GA4, 1―100 ng/g for GA7) and good relative standard deviation ranges(4.8%―9.4% for the intra-day test and 3.5%―11.9% for the inter-day test).  相似文献   
8.
Sincelaserirradiationwasappliedtoinducemutationofstrainsofmicroorganism,thismethodhasdrawnmanyrelatedresearcher’sattention.Inthisstudy,wenotonlyusedlaserirradiationonGibberellinproducedstraininordertoimprovetheyieldofGibberellin,butalsocomparedthemu…  相似文献   
9.
由异丙醇/硫酸铵-水溶液组成的醇盐-水双液相萃取体系,可用于植物激素赤霉素的提取。研究了醇盐比、体系pH及赤霉素浓度对萃取结果的影响。结果表明在醇盐比(异丙醇/硫酸铵)为1.5mL/4.3g,体系酸度为pH4.0,赤霉素浓度小于0.064g/L时,赤霉素在该体系的一步提取率可达93.47%,富集倍数为11.36。发酵液中常含的氯化钠和葡萄糖,在最佳实验条件下对赤霉素的提取没有影响。用紫外、红外色谱等方法证实,异丙醇提取的赤霉素结构稳定,纯度高。绿豆发芽生长实验表明,该体系提取的赤霉素生物活性不变。  相似文献   
10.
固相萃取-高效液相色谱测定番茄中的赤霉素GA3残留   总被引:4,自引:0,他引:4  
建立了固相萃取-高效液相色谱(SPE-HPLC)法分析番茄中赤霉素GA3残留量的方法.研究了不同填料的固相萃取小柱对番茄中赤霉素的萃取回收率以及各自的纯化结果.该方法线性范围为0.21~1.05×102mg/L,检出限为0.011mg/kg,在优化条件下,以C18小柱萃取样品的效果最好,加标回收率为88.45%~95.90%,其RSD为1.15%~6.56%.  相似文献   
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