Graptophyllum pictum (L.) Griff is a medicinal shrub belonging to the Acanthaceae family and is traditionally used to treat various diseases. Therefore, this study aims to evaluate the pharmaceutical properties and phytochemical profiles of the methanolic extract of G. pictum. The results showed that the extract had potent antioxidant activity against 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals with IC50 values of 49.00±3.20 μg/mL and 70.18±3.27 μg/mL, respectively. It also exhibited cytotoxic effects on the human breast (MCF-7) and liver (HepG2) carcinoma cells with growth inhibition percentages of 74.29±1.53% and 64.90±1.94%, respectively. The analysis showed that the extract had inhibitory effects on α- glucosidase activity with IC50 value 194.59±15.59 μg/mL, indicating its potential to be developed as an antidiabetic agent. Furthermore, it had antibacterial properties against four test strains, and the highest activity was found against Bacillus subtilis strain ATCC 19659, with MIC and MBC values of 625 μg/mL and 1250 μg/mL, respectively. Phytochemical tests indicated the presence of alkaloids, flavonoids, and terpenoids in the extract, with total phenolic content (TPC) and total flavonoid content (TFC) of 41.17±2.38 mg GAE/g and 26.52±0.61 mg QE/g, respectively. Based on the Gas Chromatography-Mass Spectrometry (GC-MS) analysis, it contained several active compounds, including eicosane, 2,4-di-tert-butylphenol, hentriacontane, tetracosane, octacosane, sulfurous acid, 2- methylhexacosane, docosane, heneicosane, 1-propene-1,2,3-tricarboxylic acid, tributyl ester, and pentacosane.

Keywords: Antioxidant; cytotoxic; flavonoids; phytochemical; phenols; α-glucosidase inhibitor