首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12篇
  免费   1篇
机械仪表   1篇
轻工业   10篇
武器工业   2篇
  2020年   2篇
  2016年   1篇
  2013年   1篇
  2012年   2篇
  2011年   1篇
  2010年   1篇
  2009年   1篇
  2007年   1篇
  2002年   1篇
  1999年   1篇
  1993年   1篇
排序方式: 共有13条查询结果,搜索用时 250 毫秒
1.
A simple method for the analysis of capsaicin and dihydrocapsaicin in peppers by ultrasound assisted extraction (USAE) followed by gas chromatography–mass spectrometry (GC-MS) has been developed. USAE conditions were optimized by experimental design in order to maximize analyte extraction. A full factorial design involving extraction variables such as solvent (ethanol and water), extraction time (5–25 min), extraction temperature (25–50 °C), sample amount (0.25–0.5 g), and ultrasound amplitude (40–80%) was applied. The most significant conditions for capsaicinoid extraction by USAE were solvent type, extraction time, and sample amount. The obtained results were compared with other extraction methods: the official Soxhlet method and a previously reported solid phase microextraction method. Results showed that the extraction efficiency with the application of USAE (98%) was as good as that obtained with Soxhlet and the precision of recovery was less than 5%; in addition, the extraction time was decreased from 5 h to 25 min. The GC-MS analytical method was linear in the range 10–100 μg/mL for capsaicin and dihydrocpsaicin with correlation coefficient r = 0.998 and peak area variability of ~1% for both capsaicinoids. The method was applied to the analysis of 11 varieties of hot peppers cultivated in México. A large concentration range for capsaicin (101–6800 μg/g) and dihydrocapsaicin (110–2736 μg/g) was found in these pepper samples.  相似文献   
2.
The pro- or antioxygenic activity of tejpat and red chilli, their fractions extracted using various solvents, and of chlorophyll, capsaicin and dihydrocapsaicin were determined in refined sunflower oil at 37 °C. Tejpat and its fractions containing chlorophyll showed pro-oxygenic activity and the catalytic action increased with increase in concentration of chlorophyll in the fractions. On the other hand, fractions which did not contain chlorophyll, such as the aqueous extract, and chlorophyll-free spice or fractions freed of chlorophyll by column chromatography were devoid of pro-oxygenic activity. The ground red chilli and its 80:20 (v/v) ethanol/water fraction exhibited strong antioxygenic activity. On the other hand, the petroleum ether fraction showed marginal antioxygenic activity, whereas the water-soluble fraction was practically devoid of any activity in refined sunflower oil. The pungent constituents of red chilli, capsaicin and dihydrocapsaicin also exhibited considerable antioxygenic activity. © 1999 Society of Chemical Industry  相似文献   
3.
建立了用氨基固相萃取小柱净化提取液,液相色谱串联质谱(LC-MS/MS)法测定食用油中辣椒素和二氢辣椒素含量的检测方法。结果表明,辣椒素在0~100 ng/mL范围内线性关系良好(R2 = 0.998 6),平均回收率在70.6%~90.5%,相对标准偏差(RSD,n=3)在3.1%~8.9%,检出限为0.03 μg/kg;二氢辣椒素在0~20 ng/mL范围内线性关系良好(R2 = 0.998 8),平均回收率在71.5%~100.7%,相对标准偏差(RSD,n=3)在6.0%~13.2%,检出限为0.006 μg/kg。该方法简便快速、准确可靠,是鉴别地沟油和测定食用油中辣椒素类物质的有效方法。  相似文献   
4.
双波长高效液相色谱法分析催泪喷射器内容物   总被引:1,自引:0,他引:1  
建立了采用双波长,利用简单流动相组成测定催泪喷射器中各有效成分的反相高效液相色谱法。色谱柱为Kromasil C18(250 mm×4.6 mm,5μm),流动相为甲醇:水(80:20,V/V),流速0.8 mL/min,柱温25℃;紫外检测波长为227 nm和300 nm.能够清楚地分辨催泪喷射器内容物中主要的3种成分:邻氯苯亚甲基丙二腈(CS),辣椒素(OC)和二氢辣椒素(DC).该方法简便快捷,线性关系良好,结果准确可靠,对建立催泪喷射器内容物检测的新质量标准具有参考作用。  相似文献   
5.
辣椒素提取方法研究进展   总被引:2,自引:0,他引:2  
辣椒素是辣椒的主要辛辣成分。本文主要对辣椒素研究概况及生物学功能进行了综述,并对不同的辣椒素提取方法进行了探讨;同时对辣椒素的应用前景进行了展望。  相似文献   
6.
ABSTRACT: A rapid, single-stage, quantitative extraction procedure is described for high-performance liquid chromatographic (HPLC) analysis of capsaicin and dihydrocapsaicin in whole chili peppers. Individual and multiple Capsicum chinense (orange habañero) pepper samples were analyzed in a 2 y study. Peppers, both undried and dried, contained average values of 1250 ppm capsaicin and 540 ppm dihydrocapsaicin relative to undried weight. Relative to dry weight, the orange habañero peppers contained 8840 ppm capsaicin and 3940 ppm dihydrocapsaicin.  相似文献   
7.
Dihydrocapsaicin Oxidation by Capsicum annuum (var. annuum) Peroxidase   总被引:2,自引:0,他引:2  
Oxidation of dihydrocapsaicin (8-methyl-N-vanillyl-6-nonanamide) by peroxidase (EC 1.11.1.7) from Capsicum annuum var. annuum fruits yielded one absorbent oxidation product with E262= 4.7 103 M?1 cm?1. Dependence of oxidation rate on dihydrocapsaicin and H2O2 concentrations revealed Michaelis-Menten type kinetics with inhibition at high substrate concentrations and optimal pH near 6.0. Dihydrocapsaicin was oxidized by pepper peroxidase, and participation of peroxidase in capsaicinoid metabolism of pepper fruits should be taken into account.  相似文献   
8.
吴娟 《中国油脂》2020,45(12):118-121
以加标植物油为研究对象,通过优化前处理条件,用有机溶剂一步萃取植物油中的辣椒素和二氢辣椒素,再结合高效液相色谱和荧光检测器,建立了一种植物油中辣椒素、二氢辣椒素的快速检测方法。优化的前处理条件为:甲醇为萃取溶剂,萃取溶剂体积30 mL(油样质量30 g),萃取次数2次,每次萃取时间10 min。优化条件下,辣椒素、二氢辣椒素的回收率为81.08%~100.28%,日内、日间相对标准偏差分别在0.18%~1.92%和0.55%~5.14%范围内,两种目标物的检出限均为5 μg/kg。该方法前处理较为简单,省时省力、检测成本较低、实用性强,为植物油中辣椒素、二氢辣椒素提供了一种新的检测方法。  相似文献   
9.
10.
HPLC法检测辣椒不同部位中辣椒碱和二氢辣椒碱的含量   总被引:2,自引:0,他引:2  
辣椒果实中的辣味成分包括辣椒碱及其衍生物(统称为辣椒碱类化合物),其中,引起辛辣味的主要化学成分辣椒碱和二氢辣椒碱约占总量的90%以上.本试验的目的是检测不同辣椒品种的不同部位中辣椒碱和二氢辣椒碱含量.因此建立了高效液相色谱方法,采用色谱条件为:C18色谱柱(4.6mm×250mm,5μm),1‰磷酸水溶液-乙腈(600:400)为流动相,流速为1.5mL/min,柱温为30℃,检测波长为281nm.该法简便,结果准确,可用于测定辣椒中辣椒碱和二氢辣椒碱的含量.利用该方法,检测了不同辣椒品种的不同部位中辣椒碱和二氢辣椒碱的含量,结果发现印度Teja中辣椒碱和二氢辣椒碱含量最高;辣椒果实不同部位辣椒碱和二氢辣椒碱含量的趋势为胎座>果肉>种子,为合理选择果实不同部位生产辣椒碱提供参考.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号