{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T03:02:48Z","timestamp":1790478168115,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,3,3]],"date-time":"2025-03-03T00:00:00Z","timestamp":1740960000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundamental Research Funds and Doctoral Scientific Research Foundation of China West Normal University","award":["24kx010"],"award-info":[{"award-number":["24kx010"]}]},{"name":"Fundamental Research Funds and Doctoral Scientific Research Foundation of China West Normal University","award":["20E046"],"award-info":[{"award-number":["20E046"]}]},{"name":"Fundamental Research Funds and Doctoral Scientific Research Foundation of China West Normal University","award":["SZK2212"],"award-info":[{"award-number":["SZK2212"]}]},{"name":"Fundamental Research Funds and Doctoral Scientific Research Foundation of China West Normal University","award":["24kx010"],"award-info":[{"award-number":["24kx010"]}]},{"name":"Fundamental Research Funds and Doctoral Scientific Research Foundation of China West Normal University","award":["20E046"],"award-info":[{"award-number":["20E046"]}]},{"name":"Fundamental Research Funds and Doctoral Scientific Research Foundation of China West Normal University","award":["SZK2212"],"award-info":[{"award-number":["SZK2212"]}]},{"name":"Panxi Crops Research and Utilization Key Laboratory of Sichuan Province","award":["24kx010"],"award-info":[{"award-number":["24kx010"]}]},{"name":"Panxi Crops Research and Utilization Key Laboratory of Sichuan Province","award":["20E046"],"award-info":[{"award-number":["20E046"]}]},{"name":"Panxi Crops Research and Utilization Key Laboratory of Sichuan Province","award":["SZK2212"],"award-info":[{"award-number":["SZK2212"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The main objectives of this study were to develop an optimized green extraction process to obtain high contents of oleuropein and flavonoids from olive leaves. A deep eutectic solvent (DES) combined with wall-breaking extraction (WBE) was employed. A DES composed of choline chloride and ethylene glycol in a 1:2 molar ratio with 30% moisture content outperformed lactic acid and methanol as extraction solvents. The optimal conditions, determined by response surface methodology, were 30% moisture content, 140 s of wall-breaking time, and a 230 mL\/g liquid\u2013solid ratio. Under these conditions, 88.87 mg\/g DM oleuropein, 4.57 mg\/g DM luteolin-7-O-glucoside, and 114.31 mg RE\/g total flavonoids were obtained. Among three olive varieties (Arbosana, Arbequina, and Picholine) cultivated in China, young Picholine leaves exhibited the highest contents. The Picholine-enriched extract demonstrated higher antioxidant activity (ABTS\u2022+ 155.10 mg\/mL, DPPH\u2022 44.58 mg\/mL) compared to other DES-based extracts, although it was lower than that of purified compounds. Furthermore, the CCK-8 assay revealed significant inhibition of Eca-109 human esophageal cells by the Picholine-enriched extract at 25 \u00b5g\/mL for 24 h, compared to Het-1A cells. This process effectively recovers bioactive compounds from olive by-product, and shows potential for applications in nutritional supplements, cosmetics, and the food industry.<\/jats:p>","DOI":"10.3390\/molecules30051150","type":"journal-article","created":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T03:26:21Z","timestamp":1741058781000},"page":"1150","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Deep Eutectic Solvents and Wall-Breaking Technique: A New Frontier in the Extraction of Oleuropein and Flavonoids from Olive Leaves with Superior Antioxidant and Antitumor Potential"],"prefix":"10.3390","volume":"30","author":[{"given":"Yan","family":"Deng","sequence":"first","affiliation":[{"name":"College of Life Science, Environmental Science and Engineering, China West Normal University, Nanchong 637009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junlin","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Life Science, Environmental Science and Engineering, China West Normal University, Nanchong 637009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jipen","family":"Qu","sequence":"additional","affiliation":[{"name":"College of Agricultural Science, Xichang University, Xichang 615000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8674-1384","authenticated-orcid":false,"given":"Bixia","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Life Science, Environmental Science and Engineering, China West Normal University, Nanchong 637009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiao","family":"Xu","sequence":"additional","affiliation":[{"name":"College of Life Science, Environmental Science and Engineering, China West Normal University, Nanchong 637009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunyan","family":"Zhao","sequence":"additional","affiliation":[{"name":"Sichuan Yizhang Agricultural Development Co., Ltd., Nanchong 637009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7511","DOI":"10.1016\/j.chroma.2011.04.053","article-title":"New possibilities for the valorization of olive oil by-products","volume":"1218","author":"Herrero","year":"2011","journal-title":"J. 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