Safety evaluation of Morinda citrifolia (noni) leaves extract: assessment of genotoxicity, oral short term and subchronic toxicity

Abstract

Morinda citrifolia L (noni) is an evergreen or small tree that grows in many tropical regions of the world. The use of the noni leaves has not been so studied however; there are reports of its pharmacological benefits. Aims: The objective of this investigation was to assess the genotoxicity, short-term, and subchronic oral toxicity of Morinda citrifolia L leaves aqueous extract. Methods: The genotoxicity of the M. citrifolia extract was investigated by measuring the frequency of micronuclei in mice bone marrow cells. The animals were treated with three doses of the extract (500, 1000, and 2000 mg/kg). For short-term toxicity, both sexes Wistar rats received 1000 mg/kg/day for 28 days. Animals were sacrificed for hematological and biochemical evaluation. For the subchronic study, Wistar rats were administered with three doses of M. citrifolia extract (100, 300, and 1000 mg/kg) by oral route for 90 days. Mortalities, clinical signs, body weight changes, food and water consumption, hematological and biochemical parameters, gross findings, organ weights, and histological examination were monitored during the study period. Results: Genotoxicity and short-term toxicity test resulted in absence of toxicity at doses between 500 and 2000 mg/kg. Significant differences were observed in hemoglobin, and differential leukocyte count after subchronic dosing of the extract. Histology evaluation did not reveal treatment-related abnormalities. Variations observed were within to normal range and reversible. Conclusions: In summary, 1000 mg/kg orally was the NOAEL for M. citrifolia extract for effects other than transient variations in some hematological parameters within normal range.