Centre d'Analyses et de Recherche, Unité de Recherche Technologies et Valorisation Agro-alimentaire, Faculté des Sciences, Université Saint-Joseph, B.P. 17-5208 Riad El Solh, Beirut 1104 2020, Lebanon.
Centre d'Analyses et de Recherche, Unité de Recherche Technologies et Valorisation Agro-alimentaire, Faculté des Sciences, Université Saint-Joseph, B.P. 17-5208 Riad El Solh, Beirut 1104 2020, Lebanon; Ecole Supérieure d'Ingénieurs de Beyrouth (ESIB). Université Saint-Joseph, CST Mkalles Mar Roukos, P. O. Box 11-514, Riad El Solh, Beirut 1107 2050, Lebanon.
Food Chem. 2021 Apr 16;342:128236. doi: 10.1016/j.foodchem.2020.128236. Epub 2020 Oct 10.
Impact of the "Intensification of Vaporization by Decompression to the Vacuum" (IVDV) on extraction of polyphenols from olive leaves was investigated. Using Response Surface Methodology, the effect of three variables were studied: initial water content of leaves, processing time and steam pressure on total phenolic content (TPC). Extractions of TPC from leaves were achieved either using 100% water as a solvent (w), or 50% (v/v) aqueous ethanol (w). Following IVDV pretreatment, TPC yields were enhanced with both solvents by approximately 3 times compared to the negative controls. Furthermore, oleuropein and hydroxytyrosol were intensified by up to 600% and 238% respectively. Antioxidant-antiradical assays revealed higher activities, up to 3.5 times, in extracts from IVDV-treated leaves. Calculation of the extraction indices Zp, reflecting cellular damage, confirmed the beneficial effect of IVDV on the extraction yield. Finally, Scanning Electron Microscopy (SEM) permitted the morphological observation of IVDV-treated as compared to untreated leaves.
研究了减压蒸发强化（IVDV）对橄榄叶中多酚提取的影响。采用响应面法，研究了三个变量对总酚含量（TPC）的影响：叶片初始含水量、处理时间和蒸汽压力。分别使用 100%水（w）或 50%（v/v）乙醇水溶液（w）作为溶剂提取 TPC。与阴性对照相比，IVDV 预处理后，两种溶剂的 TPC 收率均提高了约 3 倍。此外，橄榄苦苷和羟基酪醇的含量分别提高了 600%和 238%。抗氧化-抗自由基测定显示，从 IVDV 处理的叶片中提取的提取物具有更高的活性，高达 3.5 倍。提取指数 Zp 的计算反映了细胞损伤，证实了 IVDV 对提取产率的有益影响。最后，扫描电子显微镜（SEM）允许观察到与未处理叶片相比，经过 IVDV 处理的叶片的形态。
