In the framework of research aimed at promoting the nutraceutical properties of the phenolic extract (BUO) obtained from an extra virgin olive oil of the Frantoio cultivar cultivated in Tuscany (Italy), with a high total phenols content, this study provides a comprehensive characterization of its antioxidant properties, both in vitro by Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity, ferric reducing antioxidant power, and 2,2-diphenyl-1-picrylhydrazyl assays, and at the cellular level in human hepatic HepG2 and human intestinal Caco-2 cells. Notably, in both cell systems, after H₂O₂ induced oxidative stress, the BUO extract reduced reactive oxygen species, lipid peroxidation, and NO overproduction via modulation of inducible nitric oxide synthase protein levels. In parallel, the intestinal transport of the different phenolic components of the BUO phytocomplex was assayed on differentiated Caco-2 cells, a well-established model of mature enterocytes. The novelty of our study lies in having investigated the antioxidant effects of a complex pool of phenolic compounds in an extra virgin olive oil (EVOO) extract, using either in vitro assays or liver and intestinal cell models, rather than the effects of single phenols, such as hydroxytyrosol or oleuropein. Finally, the selective trans-epithelial transport of some oleuropein derivatives was observed for the first time in differentiated Caco-2 cells.

中文翻译：

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人肝HepG2和肠Caco-2细胞的特级初榨橄榄油酚提取物：抗氧化活性和肠上皮运输的评估。

在旨在提高从托斯卡纳（意大利）种植的Frantoio品种的特级初榨橄榄油中获得的酚提取物（BUO）的营养保健特性的基础上，该酚具有较高的总酚含量，该研究提供了对其抗氧化特性，包括在Trolox等效抗氧化能力，氧自由基吸收能力，三价铁还原抗氧化能力和2,2-二苯基-1-picylhydrazyl检测的体外，以及在人肝HepG2和人肠Caco-2中的细胞水平细胞。值得注意的是，在两个电池系统中，H ₂ O _2之后由于BUO提取物诱导了氧化应激，因此通过调节诱导型一氧化氮合酶蛋白水平降低了活性氧，脂质过氧化和NO过量生成。平行地，在分化的Caco-2细胞（成熟的肠上皮细胞的成熟模型）上测定了BUO植物复合物的不同酚类成分的肠运输。我们研究的新颖之处在于，使用体外测定或肝和肠道细胞模型研究了特级初榨橄榄油（EVOO）提取物中复杂酚类化合物的复合物的抗氧化作用，而不是单一酚的作用，例如羟基酪醇或橄榄苦苷。最后，在分化的Caco-2细胞中首次观察到一些橄榄苦苷衍生物的选择性跨上皮运输。