{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T04:19:59Z","timestamp":1793420399869,"version":"4.5.0"},"reference-count":50,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T00:00:00Z","timestamp":1764028800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CNS-NSF-Nutrilite Research Fund for Plant Functional Substances","award":["CNS-NCL2024-312"],"award-info":[{"award-number":["CNS-NCL2024-312"]}]},{"name":"State Key Laboratory of Vegetable Biobreeding","award":["SKLVB202503"],"award-info":[{"award-number":["SKLVB202503"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32422069"],"award-info":[{"award-number":["32422069"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"2115 Talent Development Program of China Agricultural University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>Deep eutectic solvents (DESs) have attracted considerable attention in recent years because of their cost-effectiveness, safety, and sustainability. In this study, we developed 19 DESs for the extraction of antioxidant polyphenolic compounds from lotus leaves, utilizing ultrasound-assisted extraction (UAE). Among the DESs examined, choline chloride (ChCl) and lactic acid (ChCl: lactic acid) exhibited the highest extraction efficiency. The optimal conditions were established as follows: molar ratio of 1:2.6, solid-to-liquid ratio of 1:20 g\/mL, water content of 8%, and ultrasound time of 65 min, which proved to be more efficient than conventional extraction methods such as water and ethanol. Under the optimal conditions, the total phenolic content (TPC) was 187.23 \u00b1 14.67 mg GAE\/g DW, and the extracts exhibited high antioxidant activity (DPPH IC50: 0.92 \u00b1 0.23 mg\/mL; FRAP: 21.56 \u00b1 3.05 mg Trolox\/g DW). This superiority arises from the formation of robust hydrogen bonds between ChCl and lactic acid, in conjunction with improved mass transfer efficiency. This study provides a green alternative method for polyphenol extraction from lotus leaves.<\/jats:p>","DOI":"10.3390\/foods14234045","type":"journal-article","created":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T16:31:54Z","timestamp":1764088314000},"page":"4045","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Green Extraction of Lotus Leaf (Nelumbo nucifera Gaertn) Polyphenols: Unraveling the Mechanism of Ultrasound-Assisted Deep Eutectic Solvents"],"prefix":"10.3390","volume":"14","author":[{"given":"Jing","family":"Sun","sequence":"first","affiliation":[{"name":"College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengqi","family":"Qin","sequence":"additional","affiliation":[{"name":"College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luyang","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-4024-2269","authenticated-orcid":false,"given":"Xin","family":"Li","sequence":"additional","affiliation":[{"name":"College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyan","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China"},{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gang","family":"Ye","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3057-6997","authenticated-orcid":false,"given":"Jianjun","family":"Deng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China"},{"name":"Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R&D Center of Biomaterials and Fermentation Engineering, Biotech & Biomed Research Institute, School of Chemical Engineering, Northwest University, Xi\u2019an 710069, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haixia","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4867","DOI":"10.1080\/10408398.2021.2009436","article-title":"Alkaloids from lotus (Nelumbo nucifera): Recent advances in biosynthesis, pharmacokinetics, bioactivity, safety, and industrial applications","volume":"63","author":"Wang","year":"2023","journal-title":"Crit. 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