Abstract:

Morinda citrifolia Linn. (Rubiaceae) locally known as Mengkudu besar is the plant reported to have a broad range of medicinal use. The purpose of this study is to evaluate antioxidant properties of standardized fruit extracts and fractions using 1,1- diphenyl-2-picrylhydrazyl scavenging activity and β-carotene-linoleate assays and to identify the major chemical constituents of the active fractions using GC-MS analysis. The total phenolics and total flavonoids content of the fruit were also evaluated. The result showed the ethyl acetate fraction of the fruit possessed the highest bleaching ability with EC50 value of 164.09 ug/mL and the fraction was found to have the highest antioxidant property (83.46 ± 0.27% at 500 ug/mL) in β-carotenelinoleate system. Ethyl acetate fraction also has the highest total phenolics content (167.71 ± 5.30 ug/mL GAE) and total flavonoids content (22.30 ± 1.22 ug/mL QE). Three major compounds present in ethyl acetate fraction were identified as octanoic acid (16.45%), pentanoic acid (10.12%) and 2,4-bis(1,1-dimethylethyl) phenol (9.50%). In conclusion, the ethyl acetate fraction of Morinda citrifolia fruit can be an alternative source of polyphenolics with potent antioxidant activities.