Abstract

Adnan Amin*, Muhammad Ayaz Khan, Ali Zaman, Abdul Haleem Shah, Uzma Haroon, Sheikh Muhammd Farooq Azam and Muhammad Yasin

The physical immobilization of Bacillus sp GU215 on polystyrene polymer film by adsorption was performed and bacitracin (antimicrobial peptide) production by both free and immobilized cells were investigated at optimum conditions. The immobilized cells presented immediate log time within 4 h, while the free cells showed a 24 h delayed response. Likewise, free cells of Bacillus spp GU215 showed maximum zones of inhibition (18 mm) within 72 h at 30°C temperature and pH 8, whereas polystyrene polymer immobilized cells presented largest 14 mm zones of inhibitions within 48 h at same conditions as free cells. We concluded that there existed a weak physical adsorption between polystyrene polymer film and immobilized bacterial cells that rendered earlier detachment of cells and resulted in a decrease in antimicrobial activity as compared to free cells.