J Nat Prod. 2007 Dec;70(12):2049-52.
Anthraquinones with quinone reductase-inducing activity and benzophenones from Morinda citrifolia (noni) roots.
Deng Y, Chin YW, Chai H, Keller WJ, Kinghorn AD.
Two new benzophenones, 14 known anthraquinones and four other known compounds were isolated from noni roots. Some of these compounds induced quinone reductase, an antioxidant enzyme, in vitro. (original abstract available at https://www.ncbi.nlm.nih.gov/pubmed/18076142).