Phytochemical content and antioxidant activity of selected wild ulam/vegetables consumed by indigenous Jakun community in Taman Negara Johor Endau Rompin (TNJER), Malaysia

Abstract

This study aimed to investigate the phytochemical content and antioxidant activity of selected wild ulam/vegetables consumed by indigenous Jakun Community in Taman Negara Johor Endau Rompin (TNJER), Malaysia. Five ulam/vegetables were collected from TNJER, Malaysia namely Dillenia suffruticosa (pucuk simpuh), Amischotolype griffithii (tebu gogok), Paederia foetida (pucuk sekentut), Gnetum gnemon (pucuk empeng), and Barringtonia macrostachya (pucuk putat). Total phenolic content (using Folin-Ciocalteu) and total flavonoid content (using aluminium chloride colorimetric), as well as antioxidant activity using 2,2-diphenylpicrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays were determined spectrophotometrically. For the phytochemical study, D. suffruticosa showed the highest value of total phenolic content (93.87±0.10 μg gallic acid equivalent/mL) while B. macrostachya displayed the highest value of total flavonoid content (115.06±21.54 μg rutin equivalent/mL) as compared to all samples tested. For the antioxidant activity, G. gnemon showed the lowest EC50 value in DPPH assay with the value of 3.92±1.52 μg ascorbic acid/mL, indicated the strongest antioxidant potential. Meanwhile, D. suffruticosa showed the highest scavenging activity using ABTS assay (EC50 value, 7.93 μg/mL). In conclusion, ulam/vegetables of TNJER are rich in phytochemicals and antioxidant which can be a great potential for use in complementary and alternative medicines as well as functional food applications.