Pranay Punj Pankaj, Raghbendra Pratap, Kiran Kumari & M. C. Varma*
University Department of Zoology, T.M. Bhagalpur University, Bhagalpur, India
Received 21st June, 2008 ; Revised 17th August, 21108
Abstract : C-phycocyanin is a major phycobiliprotein produced by cyanobacteria. The phycobiliprotein pigments are intensively fluorescent and water-soluble. Besides light harvesting, the phycobiliproteins posses several properties of industrial and biomedical importance. Among them C-phycocyanin is the most preferred one. The present study was performed to evaluate the antibacterial activity of C-phycocyanin from Nostoc muscorum by in vitro testing on different strains of bacteria including gram positive and gram negative. C-phycocyanin was extracted and purified from Nostoc muscorum by using acetone extraction, ammonium sulphate precipitation and dialysis followed by amicon centrifugation. The C-phycocyanin precipitated at 40% (NH4)2SO4 showed single protein band at —124 kDa, water soluble protein molecule indicating the characteristic (αβ)3 subunit assembly as it was observed in electrophoretic separation on Native gel. C-phycocyanin was found to be effective against both including gram positive and gram-negative bacteria. 100μg/m1 of C -phycocyanin showed the greatest antibacterial effect over Enterobacter cloacae in 24 h and Arthrobacter nicotianae in 48 h of incubation. 100 μg/ml of C-phycocyanin showed the greatest inhibition zone over Arthrobacler nicotianae.