Production and shelf life evaluation of three different formulations of Beauveria bassiana in terms of multimetal removal

The present work describes a novel attempt to produce three different stable formulations (myco-granules, myco-tablets and myco-capsule) of Beauveria bassiana fungi targeted against multimetal (Cu, Cr, Cd, Ni, Zn and Pb) containing synthetic wastewater. Locally available low cost substrate (rice flour) was used for the production of these formulations. Shelf life of the above the formulations stored at 30 °C temperature was evaluated in terms of viability, biomass production and multimetal removal over the period of one year at a regular interval of 4 months. It was observed that myco-granules and myco-capsules were more stable formulations as compared to myco-tables in control conditions as well as with multimetal. In the initial phase of studies, maximum multimetal removal (93%) were observed with myco-granules and myco-capsules followed by myco-tablet (83.5%). The multimetal removal ability of all three formulation decreased by 37.6%, 53.1% and 48.5% for myco-granules, myco-capsules and myco-tablet, respectively, after 12 months of storage. Further, morphological changes caused by the multimetal toxicity were analyzed using SEM, AFM and FTIR. The developed formulations have the potential of remediating multimetal containing wastewater. Further, its prolonged shelf life at ambient temperature highlighted its superiority over conventional means of microbial storage.