Papageorgiou Costas S, Lyri Paraskevi, Xintaropoulou Ioanna, Diamantopoulos Ioannis, Zagklis Dimitris P, Paraskeva Christakis A
Laboratory of Transport Phenomena and Physicochemical Hydrodynamics (LTPPH), Department of Chemical Engineering, University of Patras, 26504 Patras, Greece.
Institute of Chemical Engineering Sciences, FORTH/ICE-HT, 26504 Patras, Greece.
Antioxidants (Basel). 2022 May 24;11(6):1042. doi: 10.3390/antiox11061042.
The aim of the present study was to explore the high-yield production of hydroxytyrosol, a phenolic compound with very high antioxidant capacity. leaves were chosen as feedstock as they contain significant amounts of oleuropein, which can be hydrolyzed to hydroxytyrosol. The chosen techniques are widely used in the industry and can be easily scaled up. Olive leaves underwent drying and mechanical pretreatment and extractives were transported to a solvent by solid-liquid extraction using water-ethanol mixtures. The use of approximately 60-80% ethanol showed an almost 2-fold increase in extracted phenolics compared to pure water, to approximately 45 g/kg of dry leaves. Extracted oleuropein was hydrolyzed with hydrochloric acid and the hydrolysate was extracted with ethyl acetate after pH adjustment. This step led to a hydroxytorosol content increase from less than 4% to approximately 60% / of dry extract, or 10-15 g of hydroxytyrosol recovery per kg of dry leaves.
本研究的目的是探索高产率生产羟基酪醇，一种具有非常高抗氧化能力的酚类化合物。选择树叶作为原料，因为它们含有大量的橄榄苦苷，橄榄苦苷可水解为羟基酪醇。所选用的技术在工业中广泛使用且易于扩大规模。橄榄叶经过干燥和机械预处理，提取物通过使用水 - 乙醇混合物的固液萃取法转移至溶剂中。使用约60 - 80%的乙醇相比于纯水，提取的酚类物质增加了近2倍，达到约45克/千克干叶。提取的橄榄苦苷用盐酸水解，水解产物在调节pH后用乙酸乙酯萃取。这一步骤使羟基酪醇含量从干提取物的不到4%增加到约60%，即每千克干叶可回收10 - 15克羟基酪醇。
