Biotransformation of Reactive Red 141 by Paenibacillus terrigena KKW2-005 and Examination of Product Toxicity

Abstract

Azo dyes play an important role as coloring agents in the textile, food, and pharmaceutical industries. They offer straightforward and cost-effective synthesis, stability, and a wider variety of colors than natural dyes [1][2][3]. Azo dyes absorb light in the visible spectrum due to their chemical structures, which are characterized by one or more azo groups (R1-N=N-R2) [4]. The azo can be substituted with benzene or naphthalene groups; they can contain many different substituents, such as chloro (-Cl), methyl (CH 3 ), nitro (NO 2 ), amino (NH 2 ), hydroxyl (-OH) or carboxyl (-COOH), all of which increase solubility and fixation to fibers [4]. Unfortunately, during manufacturing and use, approximately 10-15% of the dye has been reported to be released into the environment [5,6]. This wastewater is hazardous because some dyes and transformation products are mutagenic or carcinogenic [7,8].Most remediation approaches have focused on degradation by microorganisms, including bacteria, fungi, and algae [9,10]. Among these, bacterial decolorization operates faster and more efficiently [10,11]. Bacteria from the genus Paenibacillus are isolated from a variety of environments and are pertinent to humans, animals and plants [12]. Mostly discovered in soil as they are related to the roots of plants, these rhizobacteria support plant growth and development [13,14]. They are used for remediation of various industrial wastes, including petroleum, textiles, pulp and paper, and other chemical industry byproducts that unintentionally or intentionally release large amounts of organic pollutant compounds or heavy metals. They can degrade contaminants in wastewater or at the site of environmental leaks, including fluoranthene, polycyclic aromatic hydrocarbons and benzo[a]anthracene [15][16][17].The essentials affecting the decolorization and biodegradation of azo dye are temperature, pH, dye structure, dye concentration, level of agitation, oxygen, supplementation of different carbon and nitrogen sources, electron donor and redox mediator. All of these straightforwardly influence bacterial decolorization in the biological treatment process, making it more effective, faster, and virtually applicable. Tolerance to high pH is critical for A total of 37 bacterial isolates were obtained from dye-contaminated soil samples at a textile processing factory in Nakhon Ratchasima Province, Thailand, and the potential of the isolates to decolorize and biotransform azo dye Reactive Red 141 (RR141) was investigated. The most potent bacterium was identified as Paenibacillus terrigena KKW2-005, which showed the ability to decolorize 96.45% of RR141 (50 mg/l) within 20 h under static conditions at pH 8.0 and a broad temperature range of 30-40°C. The biotransformation products were analyzed by using UV-Vis spectrophotometry and Fourier-transform infrared spectroscopy. Gas chromatography-mass spectroscopy analysis revealed four metabolites generated from the reductive biodegradation, namely sodium 3-diazenylnaphthalene-1,5-disulfonate (I), sodium naph...

Microbial diversity, transformation and toxicity of azo dye biodegradation using thermo-alkaliphilic microbial consortia

“…Telke et al [ 50 ] reported naphthalene diazonium, 1, 3, 5-triazine 2, 4-diol, and p-dinitrobenzene as degradation products of RR 141, while Aniline and 1,3,5-triazine were reported by Dias et al [ 51 ] as degradation products of RR 239. Similarly, Sompark et al [ 52 ] performed GC-Ms analysis to propose RR 141 transformation pathways and reported four fragmentation patterns as 3-diazenylnaphthalene-1,5-disulfonate, sodium naphthalene-2-sufonate, 4-chloro-1,3,5-triazin-2-amine and N1-(1,3,5-triazin-2-yl) benzene-1, 4-diamine. Furthermore, Carliell et al [ 53 ] proposed the transformation of RR 141 into 1, 3, 5-triazine, 2, 4, 6-trioxo, p -diaminobenzene, 2-aminonaphthalene-1,5-disulfonic acid and 1,7-diamino-8-naphthol-3,6-disulfonic acid.…”

Screening of Azo-Dye-Degrading Bacteria from Textile Industry Wastewater-Activated Sludge

“…Because of this, UV-Vis responses cannot be directly compared with responses from techniques such as HPLC; they must complement each other. Therefore, UV-Vis analysis can be used to assess discoloration and HPLC to investigate the mechanisms of discoloration and the removal percentage [65].…”

Rice Husk—Cellulose-Based Agricultural Waste Enhances the Degradation of Synthetic Dyes Using Multiple Enzyme-Producing Extremophiles

“…Bacteria adapt well to various types of stresses, including hazardous wastes and harsh living conditions, which are considered positive features for the enhancement of many contaminated environments [ 11 ]. In particular, the activity of bacterial enzyme systems contributes to the biotransformation of toxicants into non-toxic metabolites through metabolic mechanisms [ 12 ]. Several types of enzymes have reportedly been found to be effective molecular weapons for participating in dye degradation, including oxidative enzymes (polyphenol oxidase (PPO), manganese peroxidase (MnP), lignin peroxidase (LiP), laccase (Lac), tyrosinase (Tyr), and N-demethylase), reductive enzymes (azoreductases), and immobilized enzymes (oxidoreductases)) [ 13 , 14 ].…”

“…Numerous bacterial strains have been investigated as potential candidates for functional bioremediation agents to decolorize and mineralize dyes that contaminate soil and wastewater. In a previous study, a bacterium Paenibacillus terrigena KKW2-005—isolated from dye-contaminated soil—was identified and its ability was determined to be capable of decolorizing 96.45% of the azo dye Reactive Red 141 (50 mg/L) within 20 h, at pH 8.0 and a wide range of temperatures (30–40 °C) under static conditions [ 12 ]. Pham et al (2022) investigated a novel member of the genus Bacillus —namely, Bacillus React3—which can degrade Methylene Blue (MB) during the production of the lignin peroxidase enzyme [ 11 ].…”