Antioxidant activity and heavy metals analysis in purple pigment extracted from gynochthodes sublanceolata leave

Pitang leaves extract have been traditionally used as food colourant of purple pigment by Malay and some community in Kelantan. Thus, the study was conducted to determine the antioxidant potential and heavy metal content of pitang leaves extract. In order to obtain a purple pigment, pitang leaves were extracted with methanol for three days and separated using liquid-liquid partition. Purple pigment was dried using rotoaveporator to obtain solid purple pigment. The antioxidant of solid purple pigment was determined by DPPH free radical scavenging assay. Then, the amount of heavy metal in the solid purple pigment was determined by Atomic Absorption Spectroscopy. Results indicated that the antioxidant activity of the pigment was IC₅₀ 930 μg/ml. The amount of heavy metals of Cu, Zn, Mg, K, Mn, Cd and Pb were 0.015 ± 0.007 ppm, 0.161 ± 0.002 ppm, 11.96 ± 0.029 ppm, 10.60 ± 0.483 ppm, 1.584 ± 0.010 ppm, 0.002 ± 0.007 ppm and 3.238 ± 0.020 ppm respectively. In conclusion, the purple pigment of pitang leaves have moderate antioxidant activity and the content of heavy metals were below the maximum permissible amount allowed by WHO; which indicate this pigment is safe to consume.