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

BACKGROUND

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).

CONCLUSIONS

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.