Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity

4-Nonylphenols (4-NPs) are persistent endocrine disruptors frequently found in wastewater treatment plant (WWTP) effluents and sewage sludge. This study evaluated the ability of eight bacterial strains that were isolated from sewage sludge to degrade 4-n-NP in an aqueous solution. <i>Bacillus...

Full description

Saved in:
Bibliographic Details
Main Authors: Alba Lara-Moreno, Inés Aguilar-Romero, Fernando Madrid, Jaime Villaverde, Jorge D. Carlier, Juan Luís Santos, Esteban Alonso, Esmeralda Morillo
Format: Article
Language:English
Published: MDPI AG 2025-06-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/12/6408
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849433813085585408
author Alba Lara-Moreno
Inés Aguilar-Romero
Fernando Madrid
Jaime Villaverde
Jorge D. Carlier
Juan Luís Santos
Esteban Alonso
Esmeralda Morillo
author_facet Alba Lara-Moreno
Inés Aguilar-Romero
Fernando Madrid
Jaime Villaverde
Jorge D. Carlier
Juan Luís Santos
Esteban Alonso
Esmeralda Morillo
author_sort Alba Lara-Moreno
collection DOAJ
description 4-Nonylphenols (4-NPs) are persistent endocrine disruptors frequently found in wastewater treatment plant (WWTP) effluents and sewage sludge. This study evaluated the ability of eight bacterial strains that were isolated from sewage sludge to degrade 4-n-NP in an aqueous solution. <i>Bacillus safensis</i> CN12, <i>Shewanella putrefaciens</i> CN17, and <i>Alcaligenes faecalis</i> CN8 showed the highest degradation rates, removing 100%, 75%, and 74% of 4-n-NP (10 mg L⁻<sup>1</sup>), with DT<sub>50</sub> values of 0.90, 8.9, and 10.4 days, respectively. Despite the reduction in 4-n-NP concentrations, ecotoxicity assays revealed that the resulting transformation products (TPs) were more toxic than the parent compound. To investigate the potential degradation mechanisms, in silico and gene expression analyses were conducted on <i>B. safensis</i> CN12, revealing a significant upregulation of the multicopper oxidase gene, <i>cotA</i> (7.25-fold), and the ring-cleaving dioxygenase gene, <i>mhqO</i> (13.9-fold). Although the CN12 strain showed potential for mineralization based on gene expression studies, this was not observed in the aqueous solution. However, when 4-n-NP was adsorbed on sludge and treated with CN12 in the presence of hydroxypropyl-β-cyclodextrin (HPBCD) as a bioavailability enhancer, mineralization reached up to 33%, indicating a synergistic effect with the native sludge microbiota.
format Article
id doaj-art-131fe61d0c4542e38ede2ec5fa6fa501
institution Kabale University
issn 2076-3417
language English
publishDate 2025-06-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-131fe61d0c4542e38ede2ec5fa6fa5012025-08-20T03:26:53ZengMDPI AGApplied Sciences2076-34172025-06-011512640810.3390/app15126408Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and ToxicityAlba Lara-Moreno0Inés Aguilar-Romero1Fernando Madrid2Jaime Villaverde3Jorge D. Carlier4Juan Luís Santos5Esteban Alonso6Esmeralda Morillo7Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville, SpainInstitute of Natural Resources and Agrobiology of Seville, Department of Agrochemistry, Environmental Microbiology and Soil Conservation, Spanish National Research Council (IRNAS-CSIC), 41012 Seville, SpainInstitute of Natural Resources and Agrobiology of Seville, Department of Agrochemistry, Environmental Microbiology and Soil Conservation, Spanish National Research Council (IRNAS-CSIC), 41012 Seville, SpainInstitute of Natural Resources and Agrobiology of Seville, Department of Agrochemistry, Environmental Microbiology and Soil Conservation, Spanish National Research Council (IRNAS-CSIC), 41012 Seville, SpainCentre of Marine Sciences (CCMAR), University of Algarve, Gambelas Campus, Building 7, 8005-139 Faro, PortugalDepartment of Analytical Chemistry, University of Seville, Virgen de África, 7, 41011 Seville, SpainDepartment of Analytical Chemistry, University of Seville, Virgen de África, 7, 41011 Seville, SpainInstitute of Natural Resources and Agrobiology of Seville, Department of Agrochemistry, Environmental Microbiology and Soil Conservation, Spanish National Research Council (IRNAS-CSIC), 41012 Seville, Spain4-Nonylphenols (4-NPs) are persistent endocrine disruptors frequently found in wastewater treatment plant (WWTP) effluents and sewage sludge. This study evaluated the ability of eight bacterial strains that were isolated from sewage sludge to degrade 4-n-NP in an aqueous solution. <i>Bacillus safensis</i> CN12, <i>Shewanella putrefaciens</i> CN17, and <i>Alcaligenes faecalis</i> CN8 showed the highest degradation rates, removing 100%, 75%, and 74% of 4-n-NP (10 mg L⁻<sup>1</sup>), with DT<sub>50</sub> values of 0.90, 8.9, and 10.4 days, respectively. Despite the reduction in 4-n-NP concentrations, ecotoxicity assays revealed that the resulting transformation products (TPs) were more toxic than the parent compound. To investigate the potential degradation mechanisms, in silico and gene expression analyses were conducted on <i>B. safensis</i> CN12, revealing a significant upregulation of the multicopper oxidase gene, <i>cotA</i> (7.25-fold), and the ring-cleaving dioxygenase gene, <i>mhqO</i> (13.9-fold). Although the CN12 strain showed potential for mineralization based on gene expression studies, this was not observed in the aqueous solution. However, when 4-n-NP was adsorbed on sludge and treated with CN12 in the presence of hydroxypropyl-β-cyclodextrin (HPBCD) as a bioavailability enhancer, mineralization reached up to 33%, indicating a synergistic effect with the native sludge microbiota.https://www.mdpi.com/2076-3417/15/12/6408nonylphenolbiodegradationmineralizationsewage sludge<i>Bacillus safensis</i>cyclodextrins
spellingShingle Alba Lara-Moreno
Inés Aguilar-Romero
Fernando Madrid
Jaime Villaverde
Jorge D. Carlier
Juan Luís Santos
Esteban Alonso
Esmeralda Morillo
Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity
Applied Sciences
nonylphenol
biodegradation
mineralization
sewage sludge
<i>Bacillus safensis</i>
cyclodextrins
title Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity
title_full Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity
title_fullStr Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity
title_full_unstemmed Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity
title_short Novel Bacterial Strains for Nonylphenol Removal in Water and Sewage Sludge: Insights from Gene Expression and Toxicity
title_sort novel bacterial strains for nonylphenol removal in water and sewage sludge insights from gene expression and toxicity
topic nonylphenol
biodegradation
mineralization
sewage sludge
<i>Bacillus safensis</i>
cyclodextrins
url https://www.mdpi.com/2076-3417/15/12/6408
work_keys_str_mv AT albalaramoreno novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT inesaguilarromero novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT fernandomadrid novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT jaimevillaverde novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT jorgedcarlier novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT juanluissantos novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT estebanalonso novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity
AT esmeraldamorillo novelbacterialstrainsfornonylphenolremovalinwaterandsewagesludgeinsightsfromgeneexpressionandtoxicity