A Two-Level Factorial Design for Screening Factors that Influence the Growth of E. cloacae strain UPM2021a on Acrylamide

Abstract

The world has gradually but steadily paid more attention to the use of bacteria to break down acrylamide as a bioremediation technique. Using a two-level factorial design, a previously obtained molybdenum-reducing bacterium with the ability to degrade amides was further identified on important factors influencing its optimal development on acrylamide. In order to screen five distinct parameters impacting the development of the bacterium on acrylamide, a two-level factorial design was used. Three center point replications were used in a total of 32 tests. These variables include pH, temperature, the length of the incubation period, the concentrations of acrylamide and glucose. Acrylamide concentration, pH, and incubation time were found to be key factors in this bacterium's growth on acrylamide by the two-factor factorial design and were successfully adjusted using RSM in subsequent studies. Using ANOVA, Pareto's chart, pertubation's plot, and other diagnostic plots, the significant contributing components or parameters were analyzed. The two-level factorial conclusion was supported by diagnostic plots including half-normal, Cook's distance, residual vs runs, leverage vs runs, Box-Cox, DFFITS, and DFBETAS. The acrylamide range used in this investigation is well within the range that most acrylamide-degrading bacteria have been found to tolerate. Longer incubation times allow for higher growth, and many acrylamide-degrading microorganisms have been observed to have incubation times of two to five days for optimized growth. The majority of acrylamide-degrading microorganisms thrive at circumstances that are close to neutral, and the findings of this study are consistent with published literature trends in this regard.