INHIBITORY EFFECT OF ETHANOL EXTRACT OF MELASTOMA MALABATHRICUM LEAVES ON INFLAMMATORY SPLA2 ENZYME AND ITS ABILITY TO REDUCE THE CELL VIABILITY OF PC3 CELL LINE

Melastoma malabathricum is a medicinal plant found throughout Southeast Asian countries. Traditionally M. malabathricum was used for treating diseases such as hemorrhoids, cuts and wounds, toothache, and stomachache. Scientific findings also revealed the wide pharmacological actions of various parts of M. malabathricum such as anti-nociceptive, anti-inflammatory, wound healing, anti-diarrheal, cytotoxic, and antioxidant activities. The present study evaluated the mechanism of action of the anti-inflammatory activity of M. malabathricum. Initially different solvent extracts of M. malabathricum were evaluated for total phenolics, total flavonoids, anti-oxidant activity, anti-inflammatory activity (protein denaturation), anti-cancer activity (prostate cancer cell line), and for sPLA2 inhibition. Results showed that ethanolic extract of Melastoma. malabathricum leaves showed higher phenolic and flavonoid concentrations, i.e. 36.77mg GAE/g dry wt. and 245.5 mg QE/gm of dry weight, respectively. Ethanol extract also exhibited the highest free radical scavenging activity in the DPPH method and phosphomolybdenum assay of which the IC₅₀ values were 77.424 µg/ml and 95.159 µg/ml respectively. The anti-inflammatory assay (protein denaturation assay) of leaf extract showed the IC₅₀ value of 45.518 µg/ml. Further, the extract exhibited greater sPLA2 inhibition (143.9 µg/ml) in the ELISA method against standard inhibitor thioetheramide-PC (6.73 µg/ml). Finally, the MTT assay for anti-cancer activity showed the IC₅₀ value of 630.57 µg/ml against the standard cisplatin on the prostate cancer (PC-3) cell line.