{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T14:06:40Z","timestamp":1774274800756,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T00:00:00Z","timestamp":1774224000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science and Technology Council, Republic of China","award":["NSTC111-2321-B-077-001"],"award-info":[{"award-number":["NSTC111-2321-B-077-001"]}]},{"name":"National Science and Technology Council, Republic of China","award":["NSTC112-2321-B-077-001"],"award-info":[{"award-number":["NSTC112-2321-B-077-001"]}]},{"name":"National Science and Technology Council, Republic of China","award":["NSTC113-2321-B-077-001"],"award-info":[{"award-number":["NSTC113-2321-B-077-001"]}]},{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund","doi-asserted-by":"publisher","award":["10.55776\/RIC4054324"],"award-info":[{"award-number":["10.55776\/RIC4054324"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund","doi-asserted-by":"publisher","award":["10.55776\/P36299"],"award-info":[{"award-number":["10.55776\/P36299"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund","doi-asserted-by":"publisher","award":["10.55776\/PAT9018824"],"award-info":[{"award-number":["10.55776\/PAT9018824"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Recent phytochemical investigations have demonstrated that Luvunga scandens is a rich source of structurally diverse secondary metabolites; however, its potential antioxidant-active constituents and their underlying mechanisms remain largely unexplored. In this study, an NMR-guided fractionation strategy applied to the rhizomes and leaves of L. scandens led to the isolation of ten limonoids, including three new compounds, Luvungas B\u2013D (3, 4, and 8). Their structures and absolute configurations were determined through extensive spectroscopic analysis, X-ray diffraction, and ECD calculations. Based on the isolated analogues, a biosynthetic pathway is proposed, featuring the metabolic bifurcation of a key acyclic intermediate into the isoobacunoic acid and propellane-type lineages. Biological evaluation revealed that 8 inhibits RSL3-induced ferroptosis in HepaRG liver cells with an EC50 of 16.1 \u00b5M. Mechanistic studies demonstrated that, unlike classical antioxidants, compound 8 mitigates lipid peroxidation without exhibiting direct radical-scavenging or iron-chelating activities. These findings suggest that 8 suppresses ferroptosis via non-canonical mechanisms.<\/jats:p>","DOI":"10.3390\/antiox15030402","type":"journal-article","created":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T13:07:06Z","timestamp":1774271226000},"page":"402","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["NMR-Guided Discovery of Luvunga D: A Novel Propellane-Type Limonoid from Luvunga scandens That Functions as a Non-Classical Ferroptosis Inhibitor"],"prefix":"10.3390","volume":"15","author":[{"given":"Bien-Thuy","family":"Bui Nguyen","sequence":"first","affiliation":[{"name":"Ph.D. Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Taipei 110301, Taiwan"},{"name":"National Research Institute of Chinese Medicine, Taipei 112026, Taiwan"},{"name":"Department of Pharmacognosy, Faculty of Pharmacy, University of Health Sciences, Vietnam National University Ho Chi Minh City, Ho Chi Minh City 700000, Vietnam"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hoang-Minh","family":"Bui","sequence":"additional","affiliation":[{"name":"Michael Popp Institute, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020 Innsbruck, Austria"},{"name":"Unit of Pharmacognosy, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5642-4679","authenticated-orcid":false,"given":"Chia-Ching","family":"Liaw","sequence":"additional","affiliation":[{"name":"National Research Institute of Chinese Medicine, Taipei 112026, Taiwan"},{"name":"Department of Pharmacy, School of Pharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan"},{"name":"Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 807378, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-0908-3433","authenticated-orcid":false,"given":"Quoc-Dung Tran","family":"Huynh","sequence":"additional","affiliation":[{"name":"Institute of Biological Chemistry, Academia Sinica, Taipei 115201, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1410-3516","authenticated-orcid":false,"given":"Chih-Hua","family":"Chao","sequence":"additional","affiliation":[{"name":"School of Pharmacy, China Medical University, Taichung 406040, Taiwan"},{"name":"Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 404327, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Duy-Hien","family":"Tran","sequence":"additional","affiliation":[{"name":"Ph.D. Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Taipei 110301, Taiwan"},{"name":"National Research Institute of Chinese Medicine, Taipei 112026, Taiwan"},{"name":"Department of Pharmacognosy\u2013Traditional Pharmacy, School of Pharmacy, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City 700000, Vietnam"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"I-Wen","family":"Lo","sequence":"additional","affiliation":[{"name":"National Research Institute of Chinese Medicine, Taipei 112026, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thanh-Hoa","family":"Vo","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, University of Health Sciences, Vietnam National University Ho Chi Minh City, Ho Chi Minh City 700000, Vietnam"},{"name":"Research Center for Discovery and Development of Healthcare Products, Vietnam National University Ho Chi Minh City, Ho Chi Minh City 700000, Vietnam"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6269-5088","authenticated-orcid":false,"given":"Andreas","family":"Koeberle","sequence":"additional","affiliation":[{"name":"Michael Popp Institute, Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020 Innsbruck, Austria"},{"name":"Institute of Pharmaceutical Sciences, Pharmacognosy and Excellence Field BioHealth, NAWI Graz, University of Graz, 8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8008-494X","authenticated-orcid":false,"given":"Solveigh C.","family":"Koeberle","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmacognosy and Excellence Field BioHealth, NAWI Graz, University of Graz, 8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mei-Chuan","family":"Chen","sequence":"additional","affiliation":[{"name":"Ph.D. Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Taipei 110301, Taiwan"},{"name":"School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110301, Taiwan"},{"name":"Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei 110301, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6139-1269","authenticated-orcid":false,"given":"Yu-Chi","family":"Lin","sequence":"additional","affiliation":[{"name":"National Research Institute of Chinese Medicine, Taipei 112026, 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