Growth kinetic study of electrochemically active bacterium Shewanella putrefaciens MTCC 8104 on acidic effluent of jute stick pyrolysis

Abstract

ABSTRACT Production of bioelectricity from waste streams using electrochemically active bacteria (EAB) has a great prospect. This article focuses on the assessment of the assimilation of acid-rich pyroliquid (APL), appearing from the waste stream of pyrolysis unit of jute stick, by one of EAB, Shewanella putrefaciens MTCC 8104. At the optimum temperature ( = 37°C) and pH ( = 4), the strain can assimilate up to 230 ppm of acetic acid per hour. Microscopic analysis indicates the presence of nanowires in the bacteria. Diauxic growth pattern is exhibited when both APL and whey are used as carbon sources. The minimum inhibitory concentration of acetic acid against S. putrefaciens has been determined to be 8000 ppm. Growth kinetics of the strain has been determined by using APL having acetic acid concentration between 100 and 7500 ppm, as carbon source. While the Monod model can explain the growth in the uninhibited zone, Wayman model has been proved to be the fittest by statistical analysis using the Akaike Information Criterion. The kinetic parameters μmax, Ks and Ki are 0.11 h−1, 13.17 and 75930.1 mg/L, respectively, with R 2 value of 0.977.