Phytochemical, Antioxidant and Toxicological Investigation of Morinda citrifolia L. Blossoms

Noni blossoms have a long history of medicinal uses in tropical areas. This study was conducted to investigate the major phytochemical components, toxicological properties, and antioxidant activity of noni blossoms. An HPLC-PDA method was developed and validated for the identification and quantification of major components. The major phytochemicals were iridoid glycosides, deacetylasperulosidic acid and asperulosidic acid, and flavonoids, quercetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside and kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside, each present at 3.764, 3.576, 1.513, and 3.096 mg/g, respectively. The aqueous extract of noni blossoms, at 500 μg/mL, exhibited greater antioxidant activity in the 2,2-diphenylpicrylhydrazyl radical scavenging assay than green tea (88.11 ± 0.01% versus 76.60 ± 0.05%). A primary DNA damage test in E. coli PQ37 (SOS-chromotest) and a twenty-four hour brine shrimp toxicity test did not reveal any genotoxic or cytotoxic activity. These results provide a useful reference for the identification of noni blossoms as well as preliminary evaluation of safety and efficacy. Further evaluation of the potential applications of noni blossoms is warranted.