Authentication and differentiation of Morinda citrifolia and Morinda coreia fruits and their commercial products

Abstract

Morinda citrifolia fruit juice, commonly known as noni juice, has become a globally popular health supplement. We have discovered, however, that Morinda coreia (syn. Morinda tinctoria) is frequently misidentified as noni in some regions. Phytochemical analyses of M. citrifolia fruit, M. officinalis root and M. coreia fruit were performed, during which specific iridoids had been identified in the latter for the first time. Comparison of results revealed that distinct phytochemical profiles may be used to identify commercial products containing authentic noni fruit powder versus the other two Morinda species. All authentic noni fruit products contain scopoletin, but those from M. coreia fruit and M. officinalis root do not. Asperuloside is absent in ripe noni fruit and in M. officinalis root, despite the presence of other iridoids. As such, a tell-tale indicator of M. coreia fruit powder is the absence of scopoletin accompanied by the presence of asperuloside. Using this information, a phytochemical survey of commercial powdered “noni” products purchased from major online retailers revealed that a high percentage of these were mislabeled and contained M. coreia fruit instead of authentic noni. As such, many consumers are not receiving what they believe they have purchased. Further, this presents potential risks as the safety and efficacy of these mislabeled products has not been evaluated in human studies.