{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T22:31:00Z","timestamp":1769121060877,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T00:00:00Z","timestamp":1768608000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004761","name":"Natural Science Foundation of Hunan Province,China","doi-asserted-by":"crossref","award":["2024JJ5185"],"award-info":[{"award-number":["2024JJ5185"]}],"id":[{"id":"10.13039\/501100004761","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100004761","name":"Natural Science Foundation of Hunan Province,China","doi-asserted-by":"crossref","award":["2021JJ30321"],"award-info":[{"award-number":["2021JJ30321"]}],"id":[{"id":"10.13039\/501100004761","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Key research and development project of hunan province,china","award":["2022NK2033"],"award-info":[{"award-number":["2022NK2033"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>To improve the oral bioavailability of oleanolic acid (OA), this study developed a menthol\u2013fatty acid-based hydrophobic deep eutectic solvent (HDES) system. Through a comprehensive evaluation using in vitro simulated digestion and Caco-2 cell transport models, the short-chain HDES was found to increase the apparent in vitro bioavailability index of OA by 9.3-fold compared to conventional ethanol systems, with efficacy showing clear fatty acid chain-length dependence. The mechanism was systematically investigated through spectral characterization and cellular studies, revealing a two-stage enhancement process: during the digestion phase, HDES significantly improved OA bioaccessibility to 14.30% compared to 4.90% with ethanol; during the absorption phase, it markedly increased cellular uptake to 25.79% versus 4.71% with ethanol. Molecular analysis indicated that the optimal hydrophobicity and diffusion properties of HDES contributed to this enhancement. This study reveals a fatty acid chain-length-dependent mechanism in HDES-facilitated OA delivery, providing a tunable strategy for enhancing the absorption of hydrophobic bioactive compounds.<\/jats:p>","DOI":"10.3390\/foods15020343","type":"journal-article","created":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T09:57:02Z","timestamp":1768816622000},"page":"343","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Menthol\u2013Fatty Acid HDES Boosts In Vitro Oral Bioavailability of Oleanolic Acid via Synergistic Digestive Release and Cellular Absorption"],"prefix":"10.3390","volume":"15","author":[{"given":"Qin","family":"Zhang","sequence":"first","affiliation":[{"name":"Department of Food Science and Technology, College of Food Science and Technology, Hunan Agricultural University, No. 1 Nongda Road, Furong District, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chenjia","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Food Science and Technology, College of Food Science and Technology, Hunan Agricultural University, No. 1 Nongda Road, Furong District, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Food Science and Technology, College of Food Science and Technology, Hunan Agricultural University, No. 1 Nongda Road, Furong District, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Benyang","family":"Li","sequence":"additional","affiliation":[{"name":"Xiangya School of Public Health, Central South University, 110 Xiangya Road, Changsha 410078, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chaoxi","family":"Zeng","sequence":"additional","affiliation":[{"name":"Xiangya School of Public Health, Central South University, 110 Xiangya Road, Changsha 410078, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5203","DOI":"10.1080\/10408398.2022.2153238","article-title":"Edible Pentacyclic Triterpenes: A Review of Their Sources, Bioactivities, Bioavailability, Self-Assembly Behavior, and Emerging Applications as Functional Delivery Vehicles","volume":"64","author":"Liu","year":"2024","journal-title":"Crit. 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