An overview of Mechanistic Characterization and optimization of Pullulan producing microorganism

Abstract

Pullulan is the generic name given to waterâ€Âsoluble homopolysaccharide thatis produced extracellularly by the polymorphic micromycete Aureobasidiumpullulans. It is a linear αâ€Âdâ€Âglucan, made mainly of maltotriose repeatingunits interconnected by α (1→6) linkages. The present study was carried outto isolate effective pullulan producing strains of A. pullulans from plantleaves collected from a village named Iruvaram in Chittoor district (AndhraPradesh). Two strains of A. pullulans were isolated, out of which SSW strainwas isolated from the leaves of Ficus benghalensis and SSP strain was isolatedfrom the leaves of Mangifera indica. The strains isolated proved that A.pullulans is a ubiquitous fungus and phylloplane being the important habitatof the organism. The colour variant pullulan–hyper producing strain SSWshowed colourless colonies in the production medium and produced pinkcolour pigment in the production broth. The optimization of the medium forpullulan production in SSW strain considering different carbon sources, nitrogensources, temperature and pH was carried out in the study. The confirmationand purification of exopolysaccharide was performed by thin layerchromatography using pullulan from Sigma, U.S.A as standard.