Induction of pullulanase production in Bacillus cereus FDTA-13

Studies were carried out on the production of pullulanase by a newly isolated strain Bacillus cereus FDTA-13. High titres of the enzyme were obtained in a medium containing branched polysaccharides. To further enhance the yield, induction of pullulanase using conventional inducers were studied. Maltooligosaccharides (maltose to maltotetraose) when added in the medium individually, or in a 1:1 combination of maltotriose and maltotetraose resulted different levels of pullulanase compared to control. Growth under carbon limited conditions (5 g l−1) with inducers resulted remarkably enhanced pullulanase activity. Pullulanase activity was severely repressed in presence of glucose. Low levels of pullulanase was observed in nitrogen limited medium, even with combinations of several maltosaccharides.