Extraction and quantification of carotenoids from dehydrated mini-tomatoes (Sweet Grape) by applying different solvents

Abstract Nowadays, due to events such as urbanization, globalization and industrialization there has been an increase in illnesses connected to eating. It is believed that, in part, the consumption of fruits and vegetables helps prevent many of these diseases. Tomatoes contain high contents of carotenoids, which are red-orange pigments present in some vegetables. In the case of tomatoes, the carotenoids mostly found are lycopene and beta-carotene. Lycopene is found in greater amounts and acts as an important antioxidant, whereas beta-carotene is found in lesser amounts in the fruit and presents pro-vitamin A activity. Due to these and various other functions carried out by the carotenoids, they have been determined for a long time in various foods. They are easily extracted with organic solvents but show instability when in the presence of agents such as light, oxygen and heat. Thus this study aimed to analyze the extraction and quantification processes of carotenoids from dehydrated mini-tomatoes of the variety Sweet Grape by means of the solvent combinations: acetone/petroleum ether, acetone/chloroform and acetone/hexane, in order to verify which solvent was the best for this procedure. The carotenoids were quantified using a spectrophotometer by reading at 350-600 nm, referring to the absorption peaks of beta-carotene and lycopene. The results showed that the solvent with the best performance for extraction of the carotenoids from the product in question was the combination of acetone and hexane, followed by acetone/petroleum ether and finally acetone/chloroform, the latter also presenting a more difficult operational extraction procedure. With the acetone/hexane combination average contents of 25.71 and 26.53 mg 100 g-1 beta-carotene and lycopene, respectively, were extracted, showing a statistically significant difference at the 5% level from the extractions using the other solvents.

摘要
当下，受城市化、全球化与工业化进程影响，与膳食相关的疾病发病率呈上升趋势。学界普遍认为，适量摄入果蔬可在一定程度上预防此类多数疾病。番茄中富含类胡萝卜素(Carotenoids)——一类存在于部分果蔬中的红橙色色素。就番茄而言，其主要含有的类胡萝卜素为番茄红素(Lycopene)与β-胡萝卜素(Beta-carotene)。番茄红素的含量更高，是一种重要的抗氧化剂；而β-胡萝卜素在番茄中的含量较低，但具备维生素A原活性。鉴于类胡萝卜素的上述及诸多其他生理功能，长期以来学界已在多种食品中对其开展检测。类胡萝卜素可通过有机溶剂轻松提取，但在光照、氧气与高温等条件下易发生降解失稳。据此，本研究旨在针对"甜蜜葡萄"(Sweet Grape)品种的脱水迷你番茄，探究其类胡萝卜素的提取与定量流程：选用丙酮/石油醚、丙酮/三氯甲烷(Chloroform)及丙酮/正己烷(Hexane)三种溶剂组合，以筛选出适配该实验的最优提取溶剂。本研究采用分光光度法，在350~600 nm波长区间内进行吸光度读数，依据β-胡萝卜素与番茄红素的特征吸收峰完成类胡萝卜素的定量检测。实验结果表明，从目标样品中提取类胡萝卜素时，丙酮/正己烷组合的提取效果最优，其次为丙酮/石油醚，丙酮/三氯甲烷组合的效果最差，且其操作流程更为繁琐。采用丙酮/正己烷组合提取时，β-胡萝卜素与番茄红素的平均提取含量分别为25.71 mg/100g与26.53 mg/100g，该结果与其余溶剂组合的提取结果相比，在5%显著性水平下具有统计学差异。