PHYTOCHEMICAL SCREENING, ANTIOXIDANT POTENTIAL AND CYTOTOXIC ACTIVITY OF MELASTOMA MALABATHRICUM LINN. FROM DIFFERENT LOCATIONS

Objective: The initial study was to screen the phytochemical content of methanol extract of M. malabathricum from seven different locations. The other objective was to evaluate the total phenolic content (TPC), Total flavonoid content (TFC), antioxidant potential and cytotoxic activity (on Hepatoma G2 cells) of these extracts and to determine the relationship between TPC and other parameters. Methods: The preliminary phytochemical screening for the presence of the secondary metabolite was carried out according to standard procedures. TheTPC,TFC and antioxidant activity were determined using Folin-Ciocalteu method, aluminium chloride (colorimetric) methodand1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity respectively. Results: Qualitative phytochemical screening showed the presence of tannins, analkaloid, steroids, flavonoid, phenols, terpenoids and fixed oil but tested negative for the presence of glycoside and saponins. The samples were found to have high TPC and antioxidant activity. The Bachok Kelantan sample (L7) showed highest phenolic content (671.51±50.07 mg of GAE/g) as well as highest DPPH free radical scavenging activity (80.81% and IC 50 102 µg/ml). The highest cytotoxic activity against HepG2 cells (IC 50 1.4µg/ml) was shown by KualaTerengganu, Terengganu sample (L1). The Spearman correlation showed that, there is a strong positive correlation between TPC and antioxidant activity ( r = 0.714) as well as strong negative correlation between MTT IC 50 and TPC ( R =-0.649) of M. malabathricum from different locations. Moreover, there is a weak positive correlation between TFC and antioxidant activity ( R = 0.286, p= 0.535). Also, there is poor correlation between TFC and cytotoxicity ( R =-0.216, p= 0.64). Conclusion: The phenolic compounds are associated with the cytotoxic and antioxidant activities of M. malabathricum, whereas flavonoids are poorly and weakly associated with cytotoxic and antioxidant activities of M. malabathricum respectively. The total phenolic content, mean flavonoid content and mean antioxidant activity of M. malabathricum from different locations were significantly different across seven locations (p<0.05).