Total Phenolic Content and Antioxidant Activity of Passiflora edulis Extract

Abstract

Passion fruit is a type of wild exotic plant in Malaysia. Common passion fruits planted in Malaysia are Passiflora edulis Sims (purple) and Passiflora edulis var flavicarpa (yellow). These fruits contain a high amount of antioxidants, polyphenols and vitamin C and are widely used as fruit juice, jam, and syrup product. However, there is a lack of information about the nutritional composition of the juice and seed of P. edulis (purple) cultivated in Malaysia. This study aims to determine the total phenolic contents, antioxidant activity and Vitamin C (ascorbic acid) content of P. edulis (purple) using two different solvent extraction, 70% of ethanol and 70% of methanol. The total phenolic content (TPC) was carried out by using Folin-Ciocalteu (FC) method, while the antioxidant activity was analysed using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay to determine the IC50 value of extracted samples. Ascorbic acid content from fresh juice and seeds samples was analysed by using Indophenol (DCPIP) method. The result showed that the extraction using ethanol produced the highest TPC with 9.249±0.04 mg GAE/g in seeds and 0.0139±0.02 mg GAE/g in juice, respectively.  The lowest IC50 value was obtained by sample extracted with ethanol, which was 83.85±4.66 mg/L in seed and 305.47±5.28 mg/L in juice. The seed sample (53.68±4.95 mg/100mg) exhibited a   high ascorbic acid content compared to the juice sample (46.66±3.28 mg/100mg).  In conclusion, seeds of P. edulis possessed the strongest antioxidant activity and vitamin C content. This study could contribute to information regarding the phytochemical constituents and suitable solvent for extraction of phenolic compounds that can act as antioxidants and thus promote health effects on the human body.