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1.
The present time, chloropicrin (CP) is commonly used as the fumigant for stored grain insects, nematodes, soil fungus and weed seeds. The quantitative determination of CP has been performed by total chlorine method1), colorimetric method2), and polarography3). However, these methods require a great deal of trouble. In the previous paper, the author reported on the operating conditions and retention datas for the determination of CP by gas-liquid chromatography (GLC)4). The method reported here is an application of this work for analysis of liquid soil fumigants.  相似文献   

2.
A gas-liquid chromatographic technique was applied to the separation of pyrrolnitrin and its derivatives. The simultaneous use of a flame detector and an electron capture detector made possible the distinction between the nitro derivatives of pyrrolnitrin and the other metabolites. The metabolites could be readily quantitated with the electron capture detector, offering a much more sensitive assay than the flame detector.  相似文献   

3.
A convenient gas-liquid chromatography procedure to quantify poly-beta-hydroxybutyrate and poly-beta-hydroxyvalerate in activated sludge was developed by combining lyophilization of the samples, purification of the chloroform phase by water reextraction, and the use of capillary columns. With a flame ionization detector the sensitivity was estimated at 10 g/liter.  相似文献   

4.
Metabolic modulation of acetone-butanol-ethanol fermentation by Clostridium acetobutylicum with carbon monoxide (CO) and organic acids is described. CO, which is a known inhibitor of hydrogenase, was found to be effective in the concentration range of dissolved CO corresponding to a CO partial pressure of 0.1 to 0.2 atm. Metabolic modulation by CO was particularly effective when organic acids such as acetic and butyric acids were added to the fermentation as electron sinks. The uptake of organic acids was enhanced, and increases in butyric acid uptake by 50 to 200% over control were observed. Hydrogen production could be reduced by 50% and the ratio of solvents could be controlled by CO modulation and organic acid addition. Acetone production could be eliminated if desired. Butanol yield could be increased by 10 to 15%. Total solvent yield could be increased 1 to 3% and the electron efficiency to acetone-butanol-ethanol solvents could be increased from 73 to 78% for controls to 80 to 85% for CO- and organic acid-modulated fermentations. Based on these results, the dynamic nature of electron flow in this fermentation has been elucidated and mechanisms for metabolic control have been hypothesized.  相似文献   

5.
6.
利用酵母菌发酵工业废糟渣生产单细胞蛋白 (SCP)类饲料 ,其发酵液也含有蛋白类物质 ,酸水解后用高效液相色谱法测定氨基酸含量 ,结果表明 :酵母菌发酵液中氨基酸含量全面 ,总量达 2 95 .1mg·L- 1 ,有较高的应用价值。  相似文献   

7.
本实验建立了HPLC法同时测定香菇中酒石酸、苹果酸、乙酸和柠檬酸的方法。在酸提条件下,利用Agela Venusll MP C18色谱柱,以2%CH3OH-20 mM(NH4)2HPO4(pH 2.40)为流动相,流速为1.0 mL/min,柱温为35℃,检测波长为210 nm,进样量为10μL。四种有机酸均在8 min内出峰。本法准确、可靠、快速、简便,检出限较低,适合于大批量样品的分析与检测。  相似文献   

8.
气相色谱法测定了发酵液中胆固醇的含量。采用Rtx-1(100%二甲基聚硅氧烷)毛细管色谱柱、FID检测器进行分析测定。当胆固醇浓度在0~200μg/mL范围内与色谱峰面积呈良好线性关系(r=0.9981)。方法的平均回收率为99.38%,相对标准偏差为0.75%(n=8),最低检出限可达到0.816μg/mL。气相色谱法作为发酵液中胆固醇含量的快速测定方法,具有试剂用量少、操作简单、结果准确等特点。  相似文献   

9.
The chromatographic behavior of aromatic and aliphatic acids was studied using an ion-exclusive column. The conditions were determined under which the separation of the acids by single-column ion-exclusion chromatography with UV detection was the most selective and efficient. The method developed was employed for determining the content of carboxylic acids in wines.  相似文献   

10.
Fifty-eight strains of nonphotochromogenic mycobacteria representing nine different serotypes were studied, including 38 strains of Mycobacterium avium and 20 strains of Battey bacilli. The lipids were extracted from whole cells, saponified with potassium hydroxide, and esterified with diazomethane. The fatty-acid profiles determined by gas-liquid chromatography included saturated fatty acids ranging from C(8) to C(24), plus some unsaturated analogues and a branched-chain acid. No consistent differences in the fatty-acid profiles were observed between strains of M. avium and Battey bacilli. Quantitative differences in the means (significant at P < 0.01) were observed in the relative amounts of 14:0, 16:1, 18:0, 18:1, and a branched-chain acid among strains of the same serotype. We were unable to differentiate the fatty-acid profiles of recently isolated strains or those maintained in culture for more than 2 years.  相似文献   

11.
Cholera-like vibrios examined by pyrolysis gas-liquid chromatography could be distinguished from other common aerobic gram-negative bacilli, including oxidase-positive organisms, e.g., Aeromonas. Vibrios in Heiberg group I were subdivided into three types on the basis of differences in one complex in the chromatogram, and these closely corresponded with the identification as classical, El Tor, or "intermediate" biotypes of Vibrio cholerae by conventional methods.  相似文献   

12.
A rapid and accurate method is described for the determination of griseofulvin and dechlorogriseofulvin extracted from Penicillium urticae with chloroform. Thinlayer chromatography was used to tentatively identify griseofulvin or dechlorogriseofulvin, or both. Two gas-liquid chromatographic systems provided additional qualitative information and simultaneous quantitation of the individual compounds.  相似文献   

13.
反相高效液相色谱法测定烟叶中的游离氨基酸   总被引:4,自引:1,他引:3  
用不同浓度的乙醇溶液提取烟样中的游离氨基酸 ,结果显示 ,存在最佳的乙醇溶液浓度 ,使烟样中被提取的游离氨基酸总量最大 ;对比了活性炭、乙醚、5 %磺基水杨酸、阳离子交换柱的纯化效果 ,发现阳离子交换柱的纯化效果较其它三种试剂要好。在提取和纯化之后 ,采用OPA、FMOC联合在线衍生反相高效液相色谱法测定了烟样中的游离氨基酸 ,该方法使烟样中的氨基酸和亚氨基酸能被同时测定 ,并且分析方法的重现性和回收率均令人满意。最后用该方法对云南B2 F98(上部、橘黄、二等烟叶 ,98年产 )烟叶中的游离氨基酸进行了测定 ,有 15种氨基酸被测出 ,其中Pro含量最高 ,约占总量的 2 5 % ,Thr含量最低 ,约占总量的 1%。  相似文献   

14.
15.
气相色谱-质谱法测定中药沙苑子中的氨基酸   总被引:4,自引:0,他引:4  
本文利用气相色谱一质谱(GC/MS)联用技术首次对中药沙苑子中的氨基酸进行了定性定量分析。沙苑子经盐酸水解后,对其氨基酸水解液进行羟基脂化和氨基酰化的衍生化反应,利用GC/MS法共测得15种氨基酸,由外标法测定了每种氨基酸的含量。由此得出沙苑子中氨基酸的总质量分数为4.23%。  相似文献   

16.
A major growth inhibitory substance of tulip bulbs (Tulipa gesneriana L. cv Paul Richter) has been unequivocally shown to be abscisic acid (ABA). The ABA methyl ester of the free ether-soluble acid fractions of tulip organs had the identical retention time on gas-liquid chromatography with electron capture detector as authentic ABA methyl ester. In addition, the mass spectra were the same. On a unit dry matter basis, the basalplate and floral shoot contained 3.6 and 2.6 times more ABA than the fleshy scales, respectively.  相似文献   

17.
A gas-liquid chromatographic (GLC) procedure is reported for the quantitation of the trimethylsilyl (TMS) derivatives of substituted 2-hydroxy-2H-1,4-benzoxazin-3(4H)-ones (2-hydroxy-2H-1,4-benzoxazin-3(4H)-one[HBOA]; 2-hydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one[HMBOA];2,4- dihydroxy-2H-1,4-benzoxazin-3(4H)-one[DIBOA]; 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one[DIMBOA]; and 2,4-dihydroxy-7,8-dimethoxy-2H-1,4-benzoxazin-3(4H)-one[DIM 2BOA]) found in maize (Zea mays L.) extracts. Derivatized samples were chromatographed on columns with liquid phases of 2% DC-11 and 3% OV-17 and detected by flame ionization. Internal standards were methyl palmitate and methyl stearate on DC-11 and methyl behenate on OV-17. Detector response was linear to at least 5 nanomoles for TMS2-HBOA and TMS2-DIBOA and to 19 nanomoles for TMS2-DIMBOA. Standard errors of 2% or less were obtained when four replicate samples were analyzed. For each of the 15 maize lines examined, the amount of DIMBOA determined by GLC was directly proportional to the amount of ferric chloride-reactive material determined colorimetrically.  相似文献   

18.
建立了顶空毛细管气相色谱法测定阿魏酸钠中的乙醇、哌啶与吡啶。采用DB-624毛细管色谱柱,FID检测器,程序升温。3种溶剂在一定浓度范围内线性关系良好,平均回收率分别为99.3%、100.1%和99.5%,RSD均小于1.0%。  相似文献   

19.
合成气来自于煤、石油、生物质和有机废物的气化,其主要成份为CO、H2和CO2。研究发现某些厌氧菌能利用合成气生成乙醇、乙酸、丁醇和丁酸等燃料和化学品。由于生物转化所具有的优势,合成气厌氧发酵被认为是一项极具潜力和竞争力的技术,在生物质及有机废物的利用方面将发挥重要作用。对厌氧发酵合成气生产有机酸和醇的研究进展,包括利用合成气产有机酸和醇的微生物,合成气发酵的代谢途径和关键酶(一氧化碳脱氢酶/乙酰辅酶A合成酶)及用于合成气发酵的反应器等进行了综述,并对该项技术的发展提出了一些建议。  相似文献   

20.
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