In vitro root induction and studies on antibacterial activity of root extract of Costus igneus on clinically important human pathogens.

In vitro root induction and its antibacterial activity of Costus igneus was conducted. The plant C. igneus was well known for its anti-diabetic property. Traditionally the plant was used to treat fever, rash, asthma and intestinal worms. Two growth regulator IAA (Indole 3-acetic acid) and IBA (Indole butyric acid) in combinations were applied to MS medium for direct root induction. MS medium supplemented with 0.5 mg/ml IBA, induced maximum amount of root culture (fresh weight was 1.566 g and dry weight 0.102 g) after 30 days. In vitro raised roots were subjected to its antimicrobial activity. Acetone, chloroform and methanol were used as solvents to extract plant materials from IBA and IAA derived roots and the extracts were subjected to antimicrobial activity against four gram negative bacteria namely Pseudomonas aeruginosa, Klebsiella pneumonia, Salmonella sp, Proteus vulgaris. In which Klebsiella pneumonia was found to be most susceptible to both IBA and IAA derived roots. Whose zone of clearance was found to be 25 mm, which was almost equal to that of commercially available antibiotic Gentamycin.