AccScience Publishing / AJWEP / Online First / DOI: 10.36922/AJWEP026300205
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ORIGINAL RESEARCH ARTICLE

Integrated photo-assisted electrochemical oxidation and biodegradation for enhanced treatment and detoxification of dairy effluent

Elangovan Janani1 ,  Arulazhagan Pugazhendi2,3 ,  Rajasekar Aruliah1*
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1 Department of Biotechnology, Faculty of Biological Science, Thiruvalluvar University, Vellore, Tamil Nadu , India
2 Department of Marine Biology, Faculty of Marine Sciences, King Abdulaziz University, Jeddah, Mecca Province , Saudi Arabia
3 Center of Excellence in Environmental Studies, King Abdulaziz University, Jeddah, Mecca Province , Saudi Arabia
AJWEP, 026300205 https://doi.org/10.36922/AJWEP026300205
Received: 26 July 2026 | Revised: 11 September 2026 | Accepted: 17 September 2026 | Published online: 16 October 2026
© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
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Abstract

The dairy industry effluents constitute a significant environmental burden due to their elevated organic load, salinity, suspended solids, and complex mixture of protein and lipid rich compounds. Their uncontrolled discharge can induce oxygen depletion, eutrophication, ecological disturbances, and the accumulation of potentially hazardous constituents in aquatic and terrestrial ecosystems, and human health. The present study investigated a sustainable hybrid treatment approach integrating photo-assisted electrochemical oxidation with biodegradation (PEO-BIO) for dairy effluent remediation. The dairy wastewater was characterized in terms of chemical oxygen demand (COD), total organic carbon (TOC), and recalcitrant organic compounds. The photo-assisted electrochemical oxidation  (PEO) process effectively transformed complex, non-biodegradable pollutants into simpler, more biodegradable intermediates, improving the effluent’s overall biodegradability. COD removal using PEO was 89%, whereas electrooxidation achieved COD removal of 78%. Subsequent biological treatment using Enterobacter hormaechei facilitated further mineralization of the oxidized compounds, resulting in substantial reductions in COD (92%) and TOC (88%). Fourier transform infrared spectroscopy and gas chromatography–mass spectrometry confirmed the progressive degradation of aromatic, nitrogenous, and halogenated compounds into low-molecular-weight acids, aldehydes, and ketones, which were readily assimilated by the microorganisms. The integrated PEO-BIO system demonstrated higher efficiency than individual treatment processes, highlighting its effectiveness in enhancing pollutant removal efficiency and reducing toxicity. Overall, the findings indicate that the integrated PEO-BIO process is a promising, environmentally sustainable, and efficient strategy for treating dairy industrial wastewater.

Keywords
Dairy effluent
Photo-assisted electrochemical oxidation
Biodegradation
Enterobacter hormaechei
Funding
Rajasekar Aruliah acknowledges funding support from the Chief Minister’s Research Grant (Project No. CMRG-2023BBT09063), Government of Tamil Nadu, India.
Conflict of interest
The authors declare they have no competing interests.
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Asian Journal of Water, Environment and Pollution, Electronic ISSN: 1875-8568 Print ISSN: 0972-9860, Published by AccScience Publishing
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