Safety tests and antinutrient analyses of noni (Morinda citrifolia L.) leaf

BACKGROUND: Noni (Morinda citrifolia L.) leaves have a documented history of food use. However, previous safety and antinutrient studies are absent. The current investigation was conducted to assess the utility of noni leaves as food.RESULTS: No evidence of toxicity or differences in weight gain were observed in acute, subacute, and subchronic oral toxicity tests of ethanol-water (1:1 v/v) and hot-water extracts of noni leaves in mice at doses of 2000, 200, and 20 mg kg⁻¹ body weight, respectively. Acute systemic anaphylaxis tests of the ethanol-water (4:1 v/v) and hot-water extracts were negative. Further, leaf proteins were readily digested in simulated gastric fluid. Tannic acid concentrations in frozen and dried leaf were 1.6 and 25.8 g kg⁻¹, respectively. Phytic acid was not detected in the raw leaf (