Indian Journal of Science and Technology

Abstract

Objectives: To study the bio kinetics of naphthalene and anthracene biodegradation by using the pure culture of Pseudomonas stutzeri, under aerobic condition. Methods: The batch experiments was performed at various initial concentrations of naphthalene and anthracene ranging from 10 to 400 mg L-1 under aerobic conditions using an isolated bacterial culture. Biomass and degradation was measured with time for different initial liquid substrate concentrations of PAHs. The specific growth rates and degradation rate were also calculated. The kinetic parameters were estimated using Monod’s, Haldane’s, Linearized-Haldane’s models for these two substrates and also determined the Root Mean Square Error (RMSE). Findings: The specific growth rate and degradation rate was found out based on the biomass growth and degradation value of naphthalene and antharacene for different initial concentration. The maximum specific growth rates (µmax) were0.0076 and 0.00521 h-1 at naphthalene and, anthracene substrate concentration of 100 and 50, mg l-1 respectively. From these results, the maximum specific growth rate (µmax) obtained from different models for naphthalene and anthracene in the range of .0081–0.0191 and 0.00542–0.00763 h−1, respectively. The range of the values of Ks for naphthalene and anthracene indicates the ability of a microorganism to grow at low substrate levels, was from 78.65- 206.88, 14.28–28.34, respectively. Many researchers have also reported degradation rate of naphthalene and anthracene compounds inhibited at comparatively low and medium concentration. The values of the endogenous coefficients obtained are 0.0049 and0.0044 h−1 for naphthalene and anthracene, respectively. The value obtained in the present study is very much in agreement with this value of decay coefficient. Application: It was conclude that the Haldane’s model is best fitted to the PAHs degradation system. These models provided suitable prediction of the microorganism growth kinetic constants and interactions between PAHs substrates; based on the kinetic results help to design the bench scale reactor.

Keywords: Anthracene, Biodegradation, Bio Kinetics,Naphthalene,Polycyclic Aromatic Hydrocarbons (PAHs), Pseudomonas