Biodegradation and Co‐Metabolism of Monochlorophenols and 2,4‐Dichlorophenol by Microbial Consortium

Abstract

In the present study, biodegradation of monochlorophenols (MCPs) and their co‐metabolism with 2,4‐dichlorophenol (2,4‐DCP) using mixed microbial consortium has been reported. The mixed consortium has shown 44 to 100% degradation of 50 to 300 mg L–1 3‐chlorophenol (3‐CP). While in case of 4‐CP, the degradation observed was 46 to 100% of 100 to 600 mg L−1 of initial concentrations. HPLC and spectrophotometric analysis indicated that the degradation occurred via a meta‐cleavage pathway. 4‐Chlorocatechol was observed as a common intermediate for both 3‐CP and 4‐CP degradation pathways. The transformation of 4‐chlorocatechol to maleylacetate via 5‐chloro 2‐hydroxymuconic semialdehyde indicated the complete degradation of both 3‐CP and 4‐CP. The co‐metabolic study of 2,4‐DCP in the presence of MCPs showed that the degradation of 2,4‐DCP increases in the presence of 3‐CP and 4‐CP. The biodegradation (mg L−1 per day) in the quaternary mixture of MCPs and DCP occurred in the order of 3‐CP > 4‐CP > DCP > 2‐CP. The biodegradation kinetics constants obtained for 3‐CP were Rm = 1.96 mg L−1 h−1, Ks = 47.23 mg L−1, Ki = 104.12 mg L−1, and for 4‐CP were Rm = 6.33 mg L−1 h−1, Ks = 1262 mg L−1, Ki = 1408.8 mg L−1 by Andrew's substrate inhibition model using MATLAB 6.5.

Unraveling the Detoxification Mechanism of 2,4-Dichlorophenol by Marine-Derived Mesophotic Symbiotic Fungi Isolated from Marine Invertebrates

“…2,4-Dichlorophenol (2,4-DCP) has been widely used as a fungicide, pesticide, and wood preservative [4], being released in high amounts into the environment (ca. 10,000 kg in the US during 2014) according to the United States Environmental Protection Agency (US EPA), who listed it as a priority pollutant among other CPs [2,5]. Human exposure to CPs takes places by consuming substances that contain them or through skin [6].…”

“…Bioremediation is the use of living organisms in order to remove pollutants from soil and water; a method that is considered more cost-effective and environmentally friendly than the conventional techniques mentioned above [5,8]. Microorganisms—mainly bacteria and fungi—indigenous to the contaminated regions are potential candidates for the task, benefiting from their acquired enzymatic arsenal, aiming to use the contaminants as food, ideally towards their complete mineralization [10].…”

Comparative degradation between heavy and light crude oil mediated by nitrogen‐induced cell‐surface hydrophobicity

“…This observation probably can be attributed to cometabolism, whereby the presence of one hydrocarbon accelerated the degradation of a more recalcitrant hydrocarbon (Hazen, ). Patel and Kumar () demonstrated that a microbial consortium degraded 2,4‐dichlorophenols better in the presence of monochlorophenol, probably due to the similar structure of both compounds initiating common degradative pathways. Khan, Hamayun, Bibi, and Sherwani () similarly reported a 24% increase in bacterial growth in a culture containing complex pyrene (four ring) with hydrocarbons of similar ring structure such as naphthalene (two ring), anthracene (three ring), and phenanthrene (three ring), compared to growth on pyrene alone.…”

Microbial strategies driving low concentration substrate degradation for sustainable remediation solutions

“…However, many studies observed the remarkable ability of microorganisms to co-metabolize these emerging pollutants in the presence of easily biodegradable organic carbons. Cometabolism is often observed when certain compounds exhibit structural similarity to others that microorganisms are capable of degrading [124][125][126] .…”