Evaluation of Antioxidant and Antifungal Activities of Polyphenol-rich Extracts of Dried Pulp of Garcinia pedunculata Roxb. and Garcinia morella Gaertn. (Clusiaceae)
Purpose: To evaluate the antioxidant and antifungal activities of polyphenol-rich extracts of the dried fruit pulp of Garcinia pedunculata (GP) and Garcinia morella (GM) to determine their traditional claims of therapeutic activity against certain diseases.
Methods: Analysis of total phenolic (TP) and flavonoid (TF) contents of the extracts were performed by Folin-Ciocalteau and Arvouet-Grand methods. The antioxidant activity of the extracts was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2) free radical scavenging activity, reducing power and in vitro lipid peroxidation (LPO). Antifungal activity was evaluated by agar-well diffusion method while mineral content was evaluated by atomic absorption spectrophotometry (AAS).
Results: Significant amounts of TP (5.87 ± 0.06 and 5.46 ± 0.02 mg catechin eqivalents/g) and TF (5.61 ± 0.16 and 3.69 ± 0.04 mg quercetin equivalents/g) were found in the cold water (CW) extracts of GP and GM, respectively, along with DPPH free radical scavenging activity (50 % inhibitory concentration (IC50) = 3.53 ± 0.04 and 1 ± 0.03μg/mL) and H2O2-radical scavenging activity (IC50 = 1.4 ± 0.02 and 1.44 ± 0.01 μg/mL). Results indicated that the CW extracts of GP and GM were potent reducing agent than the HW extracts. CW extract of both species prevented in vitro LPO (IC50= 42 ± 0.01 and 30.36 ± 0.03 μg/mL) significantly. The antifungal activity of GP and GM extracts against some human dermatophytes was high. High concentrations of K and Fe were found in the extracts.
Conclusion: GP and GM extracts have great potential as a source for useful antioxidant and antifungal agents.
Keywords: Antioxidant, Phenolic, Flavonoid, Lipid peroxidation, Antifungal, Dermatophytes