Phenolic and flavonoid contents and antioxidant activities of selected dabai (Canarium odontophyllum) genotypes

Dabai (Canarium odontophyllum) or commonly known as ‘Sarawak olive’, is one of the potential seasonal fruits that has been given priority for development in Sarawak. In an attempt to make systematic comparisons and to identify the best genotype for further utilisation, the total phenolic and flavonoid contents and antioxidant activities of six different dabai fruit genotypes commonly available in the local markets were determined. Three edible fractions of the dabai fruit, namely the skin, pulp and kernel were also studied. Dabai skin fraction extract was found to exhibit the highest values in all four parameters studied i.e. total phenolic content (18.88 – 26.62 mg GAE/g), total flavonoid content (15.62 – 46.70 mg QE/g), DPPH free radical scavenging activity (19.90 – 30.15%) and β-carotene bleaching activity (41.75 – 61.55%). Positive correlations were observed in all four parameters studied. A negative correlation was also detected in total phenolic content and DPPH free radical scavenging activities of dabai fruit skin fraction