Proprietors of the Polynesian and South Pacific noni plant (Morinda citrifolia) believe it to be the next great panacea. Of particular interest is the substance named "xeronine" by Ralph Heinicke, former pineapple enzyme researcher for Dole. Noni's various phytochemicals are thought to have beneficial effects based on isolated findings in animal and laboratory tests. For example, a Hawaiian study suggested that high-dose intraperitoneal injections of noni extended the life of mice with lung carcinoma (Proc West Pharmacol Soc. 1994;37:145-6). A separate unpublished study reported in vitro activity against mycobacteria. Another study suggested sedative and analgesic effects on animals.
Although no human studies have been completed, there have been case reports of potential harm such as hyperkalemia (Am J Kidney Dis. 2000 Feb; 35 (2):330-2), hepatoxicity (Europ J Gastroenterol., 2005; 17:445-7) and possible Coumadin resistance (Am J Hematol. 2004 Sep;77(1)103). Furthermore, one study of noni leaf extract screening for antibacterial activity using disc diffusion demonstrated no effect on K. pneumoniae, P. aeruginosa, E. coli, S. aureus, and MRSA (Trop Biomed. 2005 Dec;22(2):165-70). Interestingly, even Heinicke admits that xeronine is almost impossible to detect, and that noni's activity is dependent upon fresh fermentation and gastric motility. After a comprehensive review, Dixon concluded that "the celebrity of noni is out of proportion to the facts" (Economic Botany. 1999. 53(1) pp 5 1-68).
Despite the paucity of evidence, noni has attracted many ardent followers including spokesman actor Danny Glover (star of "Lethal Weapon" and admirer of Hugo Chavez). The National Center for Complementary and Alternative Medicine is currently enrolling patients in a Phase I clinical trial, but at this point it appears that one can get the same antioxidant properties from a can of V-8 juice, and that the "energy boost" achieved is merely from all the sugar sweeteners used to conceal its putrid taste and smell. Perhaps it is no coincidence that the only existing patent for noni is actually for "eliminating grease, sewage odor and hydrogen sulfide from restaurant grease traps and municipal sewage systems" (patent #4666604).