摘要
以洋葱、胡萝卜和姜黄为原料，以乙醇为提取溶剂，研究了洋葱、胡萝卜和姜黄中天然染料的提取与表征，探讨了天然染料的物理性质和光谱特征。得到的染料颜色分别为深褐色、深红色和深橙色，洋葱、胡萝卜和姜黄的染料得率分别为5.00%、11.10%和16.00%。他们还进行了其他物理分析，如熔点、溶解度和pH值测定。经物理分析，得到的熔点为26?-洋葱和34?胡萝卜46?——姜黄。溶解性试验表明，洋葱不溶于冷水而溶于热水，胡萝卜溶于冷水，姜黄溶于冷水而溶于热水。洋葱的pH值为4.04，胡萝卜的pH值为4.57，姜黄的pH值为5.25，这表明每种提取的染料中都含有酸性成分。还进行了光谱分析，观察到所有染料都在可见区域吸收，结果还显示洋葱、胡萝卜和姜黄的最大吸收波长分别为400nm、400nm和420nm，这表明每种染料提取物中都存在共轭键和发色团。 Fourier Transformed Infra-Red (FTIR) spectroscopic analyses were also carried out on the dye stuff and the results showed various peaks with IR frequencies. The peaks at 3288 cm-1, 3257 cm-1, and 3339 cm-1 for onion, carrot and turmeric respectively is an indicative of the presence of O-H stretch, H-bonded of alcohol/phenol in the dyestuffs. The peaks at 1640 cm-1, 1636 cm-1, and 1677 cm-1 are indicative of the -C=C- stretch of conjugated alkene/ ketone. And the peaks at 1408 cm-1, 1408 cm-1 and 1580 cm-1 for onion, carrot and turmeric dye extracts respectively are indicative of -C-C- stretch in rings (aromatics). The peaks at 1777 cm-1 and 1710 cm-1 for onion and carrot are indicative of presence of C=O stretch of carbonyl group/carboxylic acids. These spectral features relate to the main quality attributes of the three dyestuffs that can be determined using infrared spectroscopy. Based on obtained results, it can be concluded that the quality parameters of the natural dyestuffs from onion(Allium cepa),carrot (DaucuscarotaL.) and turmeric(Curcuma longa) can be predicted based on spectral features.
关键字
染料，提取，表征，洋葱(葱属)，胡萝卜(胡萝卜属)，姜黄(姜黄)
引用
愤怒的期刊:
Melford C. Egbujor, Christiana I. Agunwa, Innocencia C. Chidebelu, Erasmus O. Anieze;乌戈玛·c·奥涅杰，薇薇安·i·奥康科沃;Chigbundu N. Emeruwa“从洋葱(Allium Cepa)鳞茎、胡萝卜(Daucus Carota L.)中提取天然染料及其表征”根和姜黄根《标志性研究与工程杂志》第6卷第8期2023年第130-141页
IEEE:
Melford C. Egbujor, Christiana I. Agunwa, Innocencia C. Chidebelu, Erasmus O. Anieze;乌戈玛·c·奥涅杰，薇薇安·i·奥康科沃;Chigbundu N. Emeruwa“从洋葱(Allium Cepa)鳞茎、胡萝卜(Daucus Carota L.)中提取天然染料及其表征”姜黄根(Curcuma Longa)标志性研究和工程期刊6 (8)
