Food Chemistry 116 (2):505-508. 2009.
Development and validation of an RP-HPLC method for the analysis of anthraquinones in noni fruits and leaves.
Deng S, West BJ, Jensen CJ, Basar S, Westendorf J.

An HPLC method was developed for the analysis of anthraquinones in noni fruits and leaves.  Lucidin, rubiadin and alizarin were not detected in any samples. Only trace amounts of 5,15-dimethylmorindol were detected in the fruit and leaves.  The presence of only trace amounts in fruit and leaves eliminates safety concerns regarding anthraquinone content. (original abstract available at https://www.sciencedirect.com/science/article/pii/S0308814609002696).