Evaluation of Phytochemicals and Antimicrobial Activity of White and Blue Capitulum and Whole Plant of Silybum Marianum

3 Abstract: Phytochemicals are nonessential nutrients derived from plants, most of them are physiologically active. Majority of the phytochemicals have been known to beer therapeutic activities like antibacterial, antioxidant, antifungal, antispasmodic, anticancer, hepatoprotective etc. Chemical compounds with antimicrobial activity isolated from plants have enormous therapeutic potential and are effective in the treatment of infectious diseases while magitating many of the side effects that are often caused by synynthati c antimicrobial agents. The aqueous extracts of blue and white flowering Silybum marianum were subjected for qualitative and quantitative phytochemical evaluation and the crud ethanolic extract for antimicrobial activity. Data shows that flavonoids, phenols and tannins are present in both blue and white flowering (whole) plant of S.marianum while saponin and alkaloid were not detected. It has been found that, flavonoids are in high quantity (21%) in blue flowering and less (19%) in the white flowering plant. Contents of phenol and tannins are noted very less as compared to flavonoid i.e. 0.430 % phenol is recorded in blue flowering and 0.4321% in the white flowering plant. Contents of tannin is noted high in the white flowering (0.8455%) and less (0.6930%) in the blue flowering (whole) plant of S. marianum. Silymarin has been found very active against all gram positive bacteria and demonstrated moderate to significant antibacterial activity against tested pathogens, while inactive against gram negative bacteria and fungi.