Phytochemical Characterization and Evaluation of Crude Extract from Ruellia patula Leaves for Antimicrobial, Antioxidant and In Vitro Anti-Inflammatory Activities

Ruellia patula belongs to the family Acanthaceae. The leaves of this plant possess tremendous medicinal values like treating wounds, eyesores, gonorrhea, syphilis and renal infections. Phytochemicals extracted using four different solvents namely hexane, acetone, methanol and water by maceration technique were qualitatively analysed by chemical tests. Total phenolic content was estimated as 142.94 +/- 1.01, 104.41 +/- 7.06, 14.37 mg Gallic Acid Equivalent/g of extract in acetone, methanol, and aqueous extracts respectively. Total flavonoid content was estimated as 37.49 +/- 1.83, 26.73 +/- 10.65 mg Quercetin Equivalent/g of extract in acetone and methanol extracts respectively. The antimicrobial activity of plant extracts was determined by agar well diffusion assay and minimum inhibitory concentration test, acetone extract showed better results for both assays. The minimum inhibitory concentration of acetone extract against five different organisms were determined as, Bacillus subtilis-202 mg/ml, Escherichia coli-208 mg/ml, Staphylococcus aureus-208 mg/ml, Pseudomonas aeruginosa-203 mg/ml and for Proteus mirabilis-200 mg/ml. Antioxidant activity of extracts was evaluated by 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay, and IC50 values of methanol and acetone extracts were estimated as 146.45 and 153.81 mu g/ml respectively. Anti-inflammatory activity of extracts estimated using protein denaturation inhibition assay resulted in better anti-inflammatory property associated with acetone extract. Based on the results, the acetone and methanol extracts showed better activities at a lower concentration, further gas chromatography-mass spectrometry analysis of these extracts was carried out and biological activity of components were determined from literature survey.