Chatzimitakos Theodoros, Athanasiadis Vassilis, Kotsou Konstantina, Bozinou Eleni, Lalas Stavros I
Department of Food Science & Nutrition, University of Thessaly, Terma N. Temponera Str., 43100 Karditsa, Greece.
Antioxidants (Basel). 2023 Aug 12;12(8):1605. doi: 10.3390/antiox12081605.
is among the species of the genus Citrus that dominates the world market. It is highly nutritious for humans as it contains twice the amount of the suggested daily intake of ascorbic acid and is also a good source of phenolic compounds, carotenoids, and other bioactive compounds. This study aimed to identify the optimal extraction procedures and parameters to obtain the maximum quantity of bioactive components from lemon peel by-products. Various extraction techniques, including stirring, ultrasound, and pulsed electric field, were evaluated, along with factors such as extraction time, temperature, and solvent composition. The results revealed that simple stirring for 150 min at 20 °C proved to be the most effective and practical method. The ideal solvent mixture consisted of 75% ethanol and 25% water, highlighting the crucial role of solvent composition in maximizing extraction efficiency. Among the extracted compounds were phenolics, ascorbic acid, and carotenoids. Under optimum extraction conditions, the extract was found to contain high total phenolic content (TPC) (51.2 mg of gallic acid equivalents, GAE/g dry weight), total flavonoid content (TFC) (7.1 mg of rutin equivalents, RtE/g dry weight), amounts of ascorbic acid (3.7 mg/g dry weight), and total carotenoids content (TCC) (64.9 μg of β-carotene equivalents, CtE/g). Notably, the extracts demonstrated potent antioxidant properties (128.9 μmol of ascorbic acid equivalents, AAE/g; and 30.3 μmol of AAE/g as evidenced by FRAP and DPPH assays, respectively), making it a promising ingredient for functional foods and cosmetics. The study's implications lie in promoting sustainable practices by converting lemon peel into valuable resources and supporting human health and wellness through the consumption of natural antioxidants.
是主导世界市场的柑橘属物种之一。它对人类具有很高的营养价值，因为它所含的抗坏血酸量是建议每日摄入量的两倍，也是酚类化合物、类胡萝卜素和其他生物活性化合物的良好来源。本研究旨在确定从柠檬皮副产品中获得最大量生物活性成分的最佳提取程序和参数。评估了各种提取技术，包括搅拌、超声和脉冲电场，以及提取时间、温度和溶剂组成等因素。结果表明，在20℃下简单搅拌150分钟是最有效和实用的方法。理想的溶剂混合物由75%乙醇和25%水组成，突出了溶剂组成在最大化提取效率方面的关键作用。提取的化合物包括酚类、抗坏血酸和类胡萝卜素。在最佳提取条件下，提取物被发现含有高总酚含量（TPC）（51.2毫克没食子酸当量，GAE/克干重）、总黄酮含量（TFC）（7.1毫克芦丁当量，RtE/克干重）、抗坏血酸量（3.7毫克/克干重）和总类胡萝卜素含量（TCC）（64.9微克β-胡萝卜素当量，CtE/克）。值得注意的是，提取物表现出强大的抗氧化性能（分别通过FRAP和DPPH测定法证明为128.9微摩尔抗坏血酸当量，AAE/克；和30.3微摩尔AAE/克），使其成为功能性食品和化妆品的有前途的成分。该研究的意义在于通过将柠檬皮转化为有价值的资源来促进可持续实践，并通过食用天然抗氧化剂来支持人类健康和福祉。
