Bacillus sp. MZ540316 was explored as new bacterial strain for production of lipopeptide biosurfactant with biodegradation efficiency against polyethylene polymers. In this study, the improved yield of biosurfactant was observed after optimizing its fermentative conditions using response surface methodology. The screening of significant nutrient media component was initially done by optimizing media components using classical methodology on the basis of emulsification index and surface tension. The optimum concentration for glucose, olive oil and yeast extract were obtained as 3 g/L, 2 g/L, and 1 g/L, respectively, after employing central composite design (CCD). This statistical methodology was further employed for estimation of optimum values for fermentative conditions with pH (7.5), fermentation period (4 days), agitation speed (150 rpm), temperature (35 degrees C), inoculum age (16 h), and inoculum size (2%). The yield of lipopeptide biosurfactant was improved with 1.42-fold higher after optimizing media component and culture condition. The suitable kinetic model was designed after studying growth kinetic and production kinetic profile under optimized fermentative conditions. The non-growth-associated behavior for production of biosurfactant would enable us to design mathematic model for cell growth kinetic and production kinetic using logistic equation and Luedeking-Piret equation, respectively. This isolate showed higher biodegradation efficiency against low density polyethylene polymer with maximum weight loss (14.33%) in compare to weight loss of high-density polyethylene pellets (10.86%).
