Nutritional content and in vitro antioxidant potential of Garcinia atroviridis (Asam gelugor) leaves and fruits.

INTRODUCTION: The objective of this study was to determine antioxidant potential of Garcinia atroviridis leaves and fruits extracts in vitro.

METHODS: Antioxidant activity was assessed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Total phenolic content (TPC) of the extracts was estimated as gallic acid equivalent by Folin-Ciocalteau method. Proximate analysis was determined based on the Association of Official Analytical Chemists (AOAC) procedures.

RESULTS: Garcinia atroviridis leaves extracted at 100 degrees C/15 min demonstrated the highest TPC value (21.21 +/- 0.28 mg GAE/mg) and was significantly different (p < 0.05) from that of leaves extracted at 60 degrees C/6 h and 40 degrees C/12 h. On the other hand, the fruit extracted at 60 degrees C/6 h showed the highest TPC value (16.23 +/- 0.18 mg GAE/mg) (p < 0.05) compared to the fruit extracted at 40 degrees C/12 h and 100 degrees C/15 h respectively. The antioxidant activities of both samples were positively correlated with the TPC values based on DPPH-radical-scavenging activity and ferric reducing power estimation. Garcinia atroviridis leaf extract contained significantly higher proteins, carbohydrate and ash contents (2.16% +/- 0.08; 15.98% +/- 0.12 and 0.72% +/- 0.07 respectively) than its fruit extract (0.46% +/- 0.08, 8.64% +/- 0.06 and 0.15% +/- 0.06) respectively). The energy content was also found to be higher in the leaf (73.64% +/- 2.15) compared to the fruit (38.38% +/- 1.72) (p < 0.05).

CONCLUSION: The findings indicate that G. atroviridis leaves and fruits have potential for use as a source of natural antioxidants and nutrients for therapeutic purposes against free radical mediated health conditions.