In vitro Antibacterial Principles of Extracts and Two Flavonoids from Clerodendrum indicum Linn

Two flavonoidal compounds, pectolinarigenin (CA-2) and hispidulin (CA-3) isolated from the stem and root of the plant Clerodendrum indicum.The petroleum ether, chloroform and ethyl acetate extracts of the same portion of the plant were screened against twelve pathogenic bacteria for their antibacterial activities.The test materials found to be significant in vitro antibacterial activities against almost all gram positive and gram negative bacteria.The zones of inhibition produced by the test materials were found to be between 6 mm and 22 mm.The MIC values of the isolated compounds were also determined against four test organisms for CA-2 and two test organisms for CA-3.The values were found to be between 64 µg/ml and 128 µg/ml.