Optimization of Process Conditions for Effective Degradation of Azo Blue Dye by Streptomyces sp. DJP15: A Secondary Modelling Approac

Abstract

The well function of aquatic and soil organisms including terrestrial, as well as those of all other living things, can be jeopardized if dyes aren't properly treated, as their degradation might lead to carcinogenic chemicals. Complete mineralization of dye is the only option, and this can be done using microorganisms. The azo blue dye inhibitory effect to its biodegradation by Streptomyces DJP15 was modelled using several inhibition kinetic models such as Haldane, Monod, Luong, Aiba, Teissier-Edwards, Han-Levenspiel and Yano. The result shows that only the Luong model failed to fit the data. The rest of the models visually ft the data although data fitting is problematic with datapoints of less than 10, which the result in this work demonstrates where it is not easy to choose the best model where nearly all of the models fit the data in a similar manner. Resorting to statistical discriminatory function, the best model was Monod with the smallest RMSE and AICc values and the highest adjR2 values and values for AF and BF close to unity. However, Monod has only two parameters and is the most robust. The Monod’s parameters were maximum specific degradation rate of 0.431 (1/h) (95% confidence interval from 0.391 to 0.456) and concentration of substrate giving half maximal rate or Ks value of 0.0001 (mg/L) (95% C.I. from -0.01 to 12.12). The confidence interval value for the Ks value was very large indicating poor data quality. This should be an important consideration in future works where the data point number can be increased to improve model fitting exercise.

Preparation and characterization of low-cost adsorbents for the efficient removal of malachite green using response surface modeling and reusability studies

“…Thus, Malachite green was considered to have an inhibiting effect on microbial development at high concentrations. These findings correspond with those previously recorded for mixed cultures 36 . We compared the evolution of the lag phase to the particular growth rate to gain advanced insight into the impact of the lag phase.…”

“…( 7 ). The R 2 formula is modified for nonlinear models to incorporate the residual mean squared error and S 2 y, which is the total variance of the Y-variable 36 . …”

Optimization study of the adsorption of malachite green removal by MgO nano-composite, nano-bentonite and fungal immobilization on active carbon using response surface methodology and kinetic study

“…Thus, malachite green was considered to have an inhibiting effect on microbial development at high concentrations. These findings correspond with those previously recorded for mixed cultures [40]. We compared the evolution of the lag phase to the particular growth rate to gain advanced insight into the impact of the lag phase.…”

“…( 7). The R 2 formula is modified for nonlinear models to incorporate the residual mean squared error and S 2 y, which is the total variance of the Y-variable [40].…”

Substrate Inhibition Kinetics Models for Fitting the Growth Rate of Phenol by an Immobilized Pseudomonas putida

“…[7,[56][57][58][59][60][61][62]. The Teissier model has found applications in the modelling the degradation or growth rate of microbes on toxic xenobiotics [7,[63][64][65][66][67][68][69][70][71][72][73][74]. The Teissier has been rarely used for modelling phenol inhibition of bacterial growth rates except in a few cases [6,6,64,75,76].…”