排序方式: 共有18条查询结果,搜索用时 125 毫秒
1.
S. Li M. Johansson J. K. Vidanarachchi J. Pickova G. Zamaratskaia 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2016,66(4):199-205
The aim of this study was to develop a high-performance thin-layer chromatography densitometry method to simultaneously evaluate levels of different biogenic amines (BAs) in beef stored aerobically at 4°C. Steaks from M. longissimus thoracis et lumborum muscles were overwrapped with polyvinyl chloride film and stored for 0, 4, 7, and 10 days. For this purpose, the solvent system and pH for the derivatization of BAs with dansyl chloride were optimized. Moreover, this method was also validated for linearity, limits of detection and quantification, precision, and recovery. As found using this method in beef samples, spermine content decreased significantly after 7 days of storage, and tyramine and cadaverine were not detected until day 10. 相似文献
2.
Twelve types of gingko flavonoids were separated with SDS/n -C4 HgOH/n- C7 Hls/H2O microernlusion as developer on polyamide film. The polarity of the microemulsion was regulated through adding or reducing water. Compared with general mobile phase, the sensitivity of detection was improved markedly and the test results were satisfied. By means of HPTLC, fingerprint was argued on gingko flavonoids. It can meet the needs of simple and convenient, reasonable standard quality control methods. 相似文献
3.
Navjot Kaur Raghbir Chand Gupta 《Communications in Soil Science and Plant Analysis》2018,49(18):2247-2255
Presently, the fingerprint analysis of kaempferol and quercetin has been developed simultaneously via High-Performance Thin Layer Chromatography (HPTLC) from leaves, stem, and inflorescence of Heteropogon contortus. The HPTLC method for kaempferol and quercetin was optimized with the elution of toluene: ethyl acetate: formic acid (7:3:0.5 v/v) as a mobile phase. The fingerprint analysis of kaempferol and quercetin was developed at Rf values of 0.39 and 0.24, respectively, and densitometric evaluation was done at 254 nm. The linear regression data for the calibration curve of both the compounds show a good linear relationship in the concentration range of 2–12 nanogram spot?1. The suggested method has been validated in terms of limit of detection (LOD) and limit of quantification (LOQ), precision, specificity, sensitivity, and accuracy. Present results show that maximum amount of kaempferol and quercetin is found in leaf extracts (35.80 and 17.01 milligram/gram of dry weight, respectively) of H. contortus. 相似文献
4.
室温条件下,以硅胶板为固定相,用5种展开剂(体积比9:9:2的甲苯-丙酮-甲酸、5.0:10.0:1.0:0.5的甲苯-甲酸乙酯-甲醇-甲酸、8.0:5.0:15.0:0.3的甲苯-三氯钾烷-丙酮-甲酸、12.5:7.5:1.8:0.6的三氯钾烷-丙酮-甲醇-水、12.5:7.5:1.8:0.6的三氯钾烷-丙酮-甲酸-水)对茶叶中的儿茶素进行薄层色谱分离,筛选出其中较优的展开剂后,进一步优化其配比,并用其分离绿茶和白茶提取物中的儿茶素以进行验证.结果表明,以体积比12.5:7.5:2.2的三氯甲烷-丙酮-甲酸为展开剂,茶叶内主要的4种儿茶素单体(EGCg、EGC、ECg、EC)可得到良好分离,绿茶与白茶提取物中的儿茶素能较好地得以分离. 相似文献
5.
本文采用双波长紫外扫描法测定饮料中糖精钠的含量。样品经乙醚提取,用展开剂三氯甲烷:丙酮:甲酸(9:3:0.1)展开,用岛津CS-930型双波长薄层扫描仪λs=225nm,λR=350nm时进行扫描,本法灵敏,准确,简便,用样量少,便于掌握,回收率为93.7%-104.6%。 相似文献
6.
Mutation breeding was used to produce mutants of the potato breeding selection NDA1725-1 with reduced levels of tuber glycoalkaloids. Excised tuber eye-pieces were exposed to 35 Gy of gamma rays from a 60Co source. In the M1V1, leaf tissue was screened using high-performance thin layer chromatography and each plant given a relative score based on a subjective rating of band intensity. Tubers were harvested from all plants that produced leaves with relatively low levels of glycoalkaloids. Tuber glycoalkaloids were quantified in the M1V2 and M1V3 using high-performance liquid chromatography, and 35% and 23% of clones with the lowest glycoalkaloid content were selected for further evaluation in each generation, respectively. In the M1V4, M1V5 and M1V6, selection was based on statistically significant differences between the mutant clones and the controls for glycoalkaloid content, as determined using a gravimetric quantification method, as well as on agronomic and quality characteristics. At the end of six clonal generations three selections exhibited acceptable levels of tuber glycoalkaloids and retained enough of the parent clone's exceptional traits to have potential in the commercial potato chip (crisp) industry. 相似文献
7.
6种有机磷农药分离及水中残留高效薄层析测定方法研究 总被引:1,自引:0,他引:1
[目的]比较有机磷农药的分离方法,用高效薄层色谱测定农药在水中残留。[方法]采用高效薄层析技术AMD和双槽展缸上行展开方式分离水中辛硫磷、毒死蜱、双硫磷、甲基异柳磷、喹硫磷和三唑磷6种有机磷农药,并对自来水中4种有机磷残留的测定方法进行研究。[结果]两种展开方式均能很好分离6种农药。AMD展开Rf值分布范围较窄(相差0.34),双槽展缸上行展开Rf值分布范围较宽(相差0.76);AMD多步展开检测灵敏度较双槽展缸上行展开低。采用双槽展缸上行展开薄层色谱法检测水中有机磷农药残留,添加回收率在86.05%-109.80%之间,添加回收率、变异系数均满足农药残留分析的要求。[结论]该研究中,双槽展缸上行展开表现出灵敏度较高、操作简便、分析速度快的特点。 相似文献
8.
Christine Reimers Beate Zielonka Rainer Stegmann Hans Steinhart 《Journal of Soils and Sediments》2001,1(3):159-163
A thin-layer Chromatographic screening-method is presented for the determination of polycyclic aromatic hydrocarbons (PAH)
in soil samples. This screening method is intended for a quick overview of the composition of a contaminant. The developed
method of separation is well suited for the semi-quantitative determination of PAH in soil samples, and can be used to identify
samples that require further analysis by means of GC or HPLC. The separation of 8 PAH groups with a maximum of 2 PAH (discernible
by selective excitation of fluorescence) each is possible. The results of the analysis based on PAH group separation can be
regarded as semi-quantitative. The extraction of PAH is effected by means of a solvent mixture consisting of n-hexane-acetone
(1:1, v/v). The extraction is aided by ultrasonic treatment. The extract is purified by application to an activated silica
gel column (solid-phase extraction). The qualitative analysis can be carried out either by visual observation or by fluorimetric
scanning (TLC-Scanner). The characteristic fluorescent colours facilitate a reliable visual identification of PAH. The applicability
of the method is shown and a comparison to other analytical methods is carried out. Some of the remarkable features of this
method are its user-friendly handling, the low consumption of solvents and the applicability without the necessity for extra
equipment. 相似文献
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10.
Eleven free amino acids were identified in the grass weed loose silky-bent (Apera spica-venti) after exposure to four rates of the thiocarbamate herbicide prosulfocarb. A new HPTLC method was developed for quantification of amino acids in raw plant extracts. A pattern of significant changes in the content of glutamine, glycine, alanine, and proline due to exposure were detected. The content of all four amino acids increased at increasing exposure rates. Quantitative analyses 7 and 21 days after herbicide application showed that over time the amount of proline increased, the alanine and glycine content decreased, and that at high exposure rates the amount of glutamine increased. Visual effects were evaluated and the biomass was measured. The visual symptoms increased and the biomass decreased with increasing exposure rates. A significant correlation between the changes in the content of the four amino acids and the visual effects and the biomasses were found. 相似文献