Response surface methodology mediated optimization of Indanthrene Blue RS by a novel isolated bacterial strain Bacillus flexus TS8

Abstract

The enhanced decolorization and detoxification of Indanthrene Blue RS dye, under aerobic conditions, by a novel isolated anthraquinone‐degrading bacterium, Bacillus flexus TS8, has been presented in this paper. The optimal decolorization conditions were determined by response surface methodology based on Box–Behnken design. The results indicated that the strain TS8 possessed the highest decolorization efficacy at pH 10.26, temperature 30.97 ºC and an inoculum size of 10.48% (v/v). It also revealed that about 98.01% of 100 mg/L of Indanthrene Blue RS could be decolorized within 24 hr under these optimized conditions. The subsequent degradation of the dye and the formation of metabolites were studied using analytical techniques such as UV‐Vis spectroscopy, FTIR, and ESI/LC‐MS analysis. The UV‐Vis analysis of the colorless bacterial cells demonstrated that Bacillus sp. TS8 possessed this decolorizing activity through biodegradation. The degraded products obtained from ESI/LC‐MS analysis were identified as 1‐hydroxyanthracene‐9, 10‐dione (m/z‐224), 1, 4‐di‐hydroxyanthracene‐9, 10‐dione (m/z‐240), and phthalic acid (m/z‐168). This study investigated the highest decolorization efficacy of strain TS8 to be utilized in the biological treatment of wastewaters containing anthraquinone dyes. Practitioner points Enhanced decolorization of anthraquinone dye wastewater. Ninety‐eight percentage of dye decolorization was obtained within 24 hr. Optimization of process parameters through the response surface methodology. ESI/LC‐MS analysis identified phthalic acid as the end product of Indanthrene Blue RS degradation. Degradation pathway for Indanthrene Blue RS is outlined.

Rapid Biodegradation of the Organophosphorus Insecticide Acephate by a Novel Strain Burkholderia sp. A11 and Its Impact on the Structure of the Indigenous Microbial Community

“…The degradation kinetic model for strain A11 was also fitted, from which we obtained 200 mg·L –1 as a watershed for the specific degradation rate, where substrate concentrations greater or less than this value showed varying performance (Figure ). This phenomenon has also been manifested in dye decolorization, where microbial growth was inhibited by the dye concentration . Similar observations indicated that the ability of strain A11 to degrade acephate increased at low acephate concentrations but decreased at higher acephate concentrations.…”

“…This phenomenon has also been manifested in dye decolorization, where microbial growth was inhibited by the dye concentration. 45 Similar observations indicated that the ability of strain A11 to degrade acephate increased at low acephate concentrations but decreased at higher acephate concentrations. This result may be attributed to the toxicity of acephate to the assayed strain.…”

Optimization of photocatalytic degradation of rhodamine B using Box–Behnken experimental design: Mineralization and mechanism

“…It is essential for the survival of all living species and covers 70% of the Earth's surface with only 2% of freshwater (Chamhuri & Ferdoushi, 2014). Although dyes are among the most dangerous pollutants, they are used in many industries such as food, cosmetics, medical, and textile as well as packaging printing (Katheresan, Kansedo, & Lau, 2018;Mohanty & Kumar, 2019). Color prevents light penetration, slows down photosynthesis activity, inhibits the growth of biota, and also has a tendency to chelate metal ions, which results in microtoxicity of fish and other organisms (Garg, Amita, Kumar, & Gupta, 2004).…”

Optimization of electro-Fenton process variables in terms of dye removal and energy consumption with response surface methodology

“…CCD, a variation of factorial design with repeated central points to estimate the pure error, is a type of experimental design that involves varying the factors at three levels: low, medium and high. CCD provides more efficient estimates of the response surface than factorial designs, especially in the near-optimal region (Mohanty & Kumar, 2020).…”