Carlucci Vittorio, Ponticelli Maria, Russo Daniela, Labanca Fabiana, Costantino Valeria, Esposito Germana, Milella Luigi
Department of Science, Universitá degli Studi della Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy.
Department of Biochemical Pharmacology & Drug Design, Institute of Molecular Biology "Roumen Tsanev", Bulgarian Academy of Sciences (BAS), Acad. G. Bonchev Str., bl. 21, 1113 Sofia, Bulgaria.
Plants (Basel). 2024 Aug 20;13(16):2310. doi: 10.3390/plants13162310.
Exhausted olive pomace (EOP) represents the principal residue of olive pomace. Several studies have optimized the extraction of specialized metabolites from the EOP of L., but a comparison between different extractive methods has not been made. For this reason, the present investigation aims to compare four different extractive methods by using water and 15% ethanol/water as extractive solvents. Specifically, based on extract antioxidant activity, the methods compared were maceration (MAC), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and Accelerated Solvent Extraction (ASE). Between these, the UAE and ASE hydroalcoholic EOP extracts were demonstrated to have the highest antioxidant activity. Subsequently, these extracts were investigated for their hypoglycemic and antiradical activity using in vitro cell-free and cell-based assays, respectively. ASE hydroalcoholic EOP extract demonstrated the greatest ability to inhibit the α-amylase enzyme and an in vitro antioxidant activity comparable to N-acetyl cysteine in HepG2 cells. UAE and ASE extracts' phytochemical characterization was also performed, identifying seven phenolic compounds, including 3-hydroxytyrosol, tyrosol, and, for the first time, salidroside. The ASE hydroalcoholic EOP extract was the richest from a phytochemical point of view, thus confirming its major biological activity. Therefore, ASE and 15% ethanol/water may represent the best extractive method for EOP nutraceutical valorization.
废弃橄榄果渣（EOP）是橄榄果渣的主要残余物。多项研究已对从油橄榄的EOP中提取特定代谢物进行了优化，但尚未对不同提取方法进行比较。因此，本研究旨在比较以水和15%乙醇/水作为提取溶剂的四种不同提取方法。具体而言，基于提取物的抗氧化活性，所比较的方法有浸渍法（MAC）、微波辅助提取法（MAE）、超声辅助提取法（UAE）和加速溶剂萃取法（ASE）。其中，UAE和ASE水醇提取物的抗氧化活性最高。随后，分别使用无细胞体外试验和基于细胞的试验对这些提取物的降血糖和抗自由基活性进行了研究。ASE水醇EOP提取物表现出最强的抑制α-淀粉酶的能力，并且在HepG2细胞中的体外抗氧化活性与N-乙酰半胱氨酸相当。还对UAE和ASE提取物进行了植物化学表征，鉴定出七种酚类化合物，包括3-羟基酪醇、酪醇，以及首次发现的红景天苷。从植物化学角度来看，ASE水醇EOP提取物最丰富，从而证实了其主要生物活性。因此，ASE和15%乙醇/水可能是EOP营养保健价值最佳的提取方法。
