Efficient In vitro Micro Propagation of Andrographis paniculata and Evaluation of Antibacterial Activity from Its Crude Protein Extract

Aims: The current study was designed to establish a cost effective protocol for rapid in vitro regeneration of Andrographis paniculata (Kalmegh) and also screening the antibacterial activity of its crude protein extracts against five human pathogenic bacteria.

Study Design: The whole investigation of in vitro micro propagation was carried out using three replications. Screening of antibacterial assay was carried out using disc diffusion method and measuring inhibition zone in millimeter.

Place and Duration of Study: The entire study was conducted in Prof. Ali. Mohammad Eunus Laboratory of the Department of Genetic Engineering and Biotechnology, University of Rajshahi, Bangladesh between October 2012 to March 2014.

Methodology: The present research work was undertaken for in vitro shoot formation, shoot multiplication, root induction and establishment of whole plantlets from shoot tips and nodal segment of Kalmegh using MS media supplemented with BAP, Kn NAA and IBA, either alone or in combination. The extracted crude protein from the leaf of Andrographis paniculata was used for antibacterial screening against three gram negative and two gram positive pathogenic bacteria and measuring the antibacterial activity as zone inhibition in millimeter. Gentamicin was used as standard drug.

Results: BAP alone showed maximum (100%) shoot regeneration from nodal segment at a concentration of 0.5 mg/l. In combination, medium having 0.5 mg/l BAP + 0.1 mg/l NAA was found to be best for auxillary shoot proliferation (90%). Maximum rooting 100% with 12.4 roots per explants were recorded on the medium containing 0.2 mg/l of IBA. The crude extract showed dose dependent strong antimicrobial activity against the entire test organism by showing zone inhibition ranging between 7.91 to 17.5 mm.

Conclusion: The protocol for in vitro micro propagation has been described here, is very simple and cost effective, which can be easily utilized for mass regeneration of Kalmegh for the purpose of drug development due to the presence of potential antibacterial polypeptide in its leaf extracts.