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排序方式: 共有6762条查询结果,搜索用时 15 毫秒
1.
Shanshan Zhuang Wenxiong Zheng Yunong Na Naiyi Chen Fan Gong Bingxuan Huang Stephen Brennan Charles Congyi Liu Jian Cheng Lukai Ma Huifan Liu 《International Journal of Food Science & Technology》2022,57(2):1093-1103
The β-Carotene (BC), an important precursor of vitamin A (VA), possesses antioxidant activity but is fat-soluble and has low bioavailability. In previous in-vitro assays evaluating antioxidant and 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) free radical scavenging, both BC and VA showed a strong ability to scavenge radicals and protected cells from oxidative stress. Here, we used artificially simulated gastrointestinal digestion and Caco-2 cell absorption models to evaluate the bioavailability of the BC during gastrointestinal digestion and absorption using high-performance liquid chromatography (HPLC) analysis. We observed high absorptive and transfer rates of BC and detected retinol metabolites (Vitamin A). Therefore, BC can be detected in the acidic gastrointestinal environment using HPLC. Optimised method provided better separation of BC and VA in the column, improving the accuracy of the test results. 相似文献
2.
Vijay Singh Sharanagat Prabhat K. Nema Lochan Singh Ankur Kumar 《International Journal of Food Science & Technology》2022,57(3):1654-1665
The effect of microwave roasting parameters (300, 450 and 600 W; 5, 10 and 15 min) on acrylamide content in sorghum grain was determined using High Pressure Liquid Chromatography (HPLC)-photo diode array (PDA) detector coupled with C-18 column. Samples roasted at 300 and 450 W did not possess acrylamide, whereas 600 W (15 min) favoured formation of 2740.19 µg/kg of acrylamide, levels far exceeding the defined European Union (EU) limits. The chronic daily intake (CDI) for acrylamide through consumption of such grain flour was 3.25–9.5-fold higher to Joint FAO/WHO Expert Committee on Food Additives (JECFA) defined high exposure limits. The margin of exposure (MOE) values ranged from 4.3 to 12.76 and from 11.07 to 32.27 for neoplastic and neurological effects, respectively, demonstrating high exposure and serious health concerns associated with dietary intake of this toxicant. This study assesses the risk for the Indian population and highlights the importance of optimising process parameters for food product to minimise such exposure risks. 相似文献
3.
Franco Cataldo 《Fullerenes, Nanotubes and Carbon Nanostructures》2004,12(4):765-779
The polyynes produced by the electric arc between graphite electrodes submerged in hexane are readily reduced to a mixture of polyenes and ene-ynes by a treatment with Zn dust and hydrochloric acid. Experimental evidences of this reduction reaction are presented by electronic absorption spectroscopy, FT-IR spectroscopy, and HPLC analysis with diode-array detector. Some consequences of this simple passage from polyynes to ene-ynes are briefly discussed in a biochemical context. 相似文献
4.
5.
Karin Bucher Jens Mende Michael Mehring Martin Jansen 《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(1):29-42
A new Eu-endohedral fullerene cage, namely, Eu@C72, was synthesized, separated, and a single isomer, Eu@C72-I, has been isolated by multi-step HPLC for the first time and characterized by LDI-TOF mass spectrometry, UV-Vis and EPR spectroscopy. Additionally, a second isomer, Eu@C72-II, has been separated by HPLC and identified by LDI-TOF mass spectrometry. 相似文献
6.
报道了 30 %苯噻·苄·乙复酸除草剂的高效液相色谱分析方法 ,采用乙腈 +甲醇+水 =30 +4 0 +30 (V/V )为流动相 ,在C18柱上UV - 2 30nm下 ,同时测定了苯噻草胺、苄嘧磺隆和乙草胺的含量 ,标准偏差分别为 0 0 38、0 0 15和 0 0 16,变异系数分别为 0 16%,0 5 9%,0 63%,回收率在 98 10 %~ 10 2 2 8%之间。 相似文献
7.
目的:改进头孢拉定制剂含量测定方法。方法:高效液相色谱条件:以Shim—Pack CLC—ODS(250mm×4.6mm)为色谱柱;柱温为35℃;流动相为水—甲醇—3.86%醋酸钠溶液-4%醋酸溶液(1364:500:30:6);流速为0.8mL·min~(-1);检测波长为254nm。结果:头孢拉定峰形良好,分离度和柱效满足药典要求,保留时间由原来的21.32min缩短至8.06min,提高了分析速度,含量测定结果与中国药典无显著差异。结论:该方法快速、准确、能更好地适用于常规检验工作和大批量生产时的质量控制。 相似文献
8.
Michael Moir 《Journal of the Institute of Brewing》1992,98(3):215-220
Flavour is arguably the most important aspect of the quality of foods and beverages. Beer, however, is an extremely complex mixture of volatile and non-volatile components, and the measurement and control of beer flavour is one of the greatest challenges in brewing research. Recent progress towards understanding the contributions of raw materials and processing conditions to the aroma and taste of beer is reviewed. 相似文献
9.
Jacques Landry Sonia Delhaye D G Jones 《Journal of the science of food and agriculture》1992,58(3):439-441
The tryptophan content of nine samples of commercial feed was determined using two procedures (I and II) differing mainly in the hydrolysis conditions used prior to analysis. With I, hydrolysis was performed with 4 M LiOH in the presence of maltodextrin with 5-methyltryptophan used as internal standard at 110°C for 24 h; with II. oxygen-free 1.3 M Ba(OH)2 was used at 125°C for 16 h. The two procedures gave identical results for a given sample indicating that the corrections for the incomplete recovery of tryptophan 5-methyltryptophan quantitation were satisfactory. 相似文献
10.
New HPLC Method to Determine Ethyl Carbamate in Alcoholic Beverages Using Fluorescence Detection 总被引:2,自引:0,他引:2
ABSTRACT: A new methodology to the quantification of ethyl carbamate (EC) has been developed. This method allows the analysis by HPLC of ethyl carbamate in samples of wine, fortified wine, and wine brandy, by a pre-column derivatization with 9-xanthydrol, and fluorescence detection. This does not require previous sample extraction or concentration. The method presents an average recovery of 96% among samples studied, a detection limit of 4.2μg/L, and an average intermediate precision of 6.3%. The comparison of the results obtained for EC analysis on the same wine brandy samples by GC/MS and HPLC are statistically indistinguishable with 97.5% probability. The results of the analysis of 42 samples are presented. 相似文献