International Biodeterioration & Biodegradation最新文献

{"title":"Subsurface mangrove rhizosphere sediment serving as a sink for endocrine-disrupting compounds and selecting archaea and bacteria and their interacting networks","authors":"Shan Zhang ,&nbsp;Yihe Zhang ,&nbsp;Jiahui Yan ,&nbsp;Guoyong Lu ,&nbsp;Ji-Dong Gu ,&nbsp;Zhong Hu","doi":"10.1016/j.ibiod.2026.106306","DOIUrl":"10.1016/j.ibiod.2026.106306","url":null,"abstract":"<div><div>Mangrove sediments are found to be an important sink for endocrine-disrupting chemicals (EDCs), but their profiles over sediment depth in relation to archaeal and bacterial communities in the subsurface rhizospheres is still unknown. Here we quantified six EDCs (E1, E2, EE2, E3, NP and BPA) in both rhizosphere (R1–R3) and non-rhizosphere (NR1–NR3) sediment cores (5–20 cm) from a subtropical mangrove and analyzed the 16S rRNA gene sequencing data with co-occurrence network analysis and multivariate statistics. Estrogens and BPA reached much higher concentrations in the subsurface rhizosphere layers than in adjacent non-rhizosphere sediments, whereas NP and BPA also showed a mid-depth accumulation maximum in the non-rhizosphere, indicating a depth-dependent accumulation zone for different EDCs. Rhizosphere sediments hosted a richer but more uneven archaeal and bacterial assemblages, and PCoA revealed a consistent difference between rhizosphere and non-rhizosphere communities. Taxonomic patterns showed that rhizosphere profiles favoured archaeal lineages such as Nitrosopumilaceae, Bathyarchaeia and Woesearchaeales, together with Desulfosarcinaceae among bacteria, while non-rhizosphere sediments contained higher proportions of Bathyarchaeia, the SG8-4 lineage and Anaerolineae. Co-occurrence network results were strongly modular, and Zi–Pi analysis identified only a small set of archaeal and bacterial connector taxa, including Lokiarchaeia, Methanomicrobiaceae, <em>Candidatus Nitrosopelagicus</em>, Methanocella and several sulfate-reducing or syntrophic bacteria, as candidates for keystone roles under EDC exposure. Mantel tests and canonical correspondence analysis indicated that gradients of EDCs together with ammonium and total nitrogen significantly structured rhizosphere communities, whereas non-rhizosphere assemblages were driven mainly by nitrogen species and salinity. These findings highlight subsurface mangrove rhizospheres as functionally important zones where EDC retention is tightly coupled to redox-active microbiota, and they point to specific archaeal and bacterial taxa that can serve as practical targets for understanding and monitoring natural attenuation in coastal wetlands.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"210 ","pages":"Article 106306"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biological treatment of sulfate-laden acidic wastewater in a semi-batch reactor: Performance optimization and microbial community dynamics","authors":"Sreekanth Yadav Golla ,&nbsp;Guntakala Venkatanaga Chandra ,&nbsp;Pranab Kumar Ghosh","doi":"10.1016/j.ibiod.2026.106276","DOIUrl":"10.1016/j.ibiod.2026.106276","url":null,"abstract":"<div><div>Sulfate-laden acidic wastewater generated from industries and mining activities is a global concern due to its adverse effects. To address this challenge, a bench-scale sulfidogenic semi-batch reactor (SmBR) inoculated with mixed bacterial culture was operated for 281 days to evaluate the effect of sulfate (500–4500 mg/L) and acidic conditions (pH 6.0-1.85) on sulfate removal and microbial communities. The optimum <span><math><mrow><mtext>COD</mtext><mo>/</mo><msubsup><mtext>SO</mtext><mn>4</mn><mrow><mn>2</mn><mo>‐</mo></mrow></msubsup></mrow></math></span> ratio and HRT were found to be 0.7 and 4 days, respectively. The SmBR achieved a sulfate and COD removal of 80 % and 87 %, respectively, with an influent sulfate concentration of 4500 mg/L and a <span><math><mrow><mtext>COD</mtext><mo>/</mo><msubsup><mtext>SO</mtext><mn>4</mn><mrow><mn>2</mn><mo>‐</mo></mrow></msubsup></mrow></math></span> ratio of 0.7, and the effluent pH increased from 2.0 to 7.2. Further decreasing the feed pH to 1.85 resulted in a sharp decline in the reactor performance, which was recovered within 30 days by adjusting operational conditions. Electron flow from lactate to sulfate reduction varied between 86 % and 91 %, demonstrating the effective utilization of substrate. 16S rRNA sequencing revealed that the decrease in influent pH from 6.0 to 2.5 led to a shift in microbial diversity towards a specialized group of SRB, particularly <em>Desulfobacterota (Desulfovibrio genus),</em> which increased from 12 to 45 %, emphasizing their crucial role in sulfate removal. The mixed bacterial culture developed in the SmBR could be suitable for treating industrial sulfate-laden acidic wastewaters such as acid mine drainage, lead acid battery manufacturing wastewater, and secondary lead smelting plant wastewater. The findings of this study offer a sustainable bioremediation approach for treating sulfate-laden acidic wastewater.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106276"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145922623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification and characterization of a novel monooxygenase for 5-hydroxypicolinic acid degradation in gram-positive bacteria","authors":"Qimiao Xu ,&nbsp;Fuyu Song ,&nbsp;Yinhu Jiang ,&nbsp;Ye Song ,&nbsp;Qi Zhao ,&nbsp;Jian He ,&nbsp;Lingling Zhao ,&nbsp;Jiguo Qiu","doi":"10.1016/j.ibiod.2026.106286","DOIUrl":"10.1016/j.ibiod.2026.106286","url":null,"abstract":"<div><div>5-Hydroxypicolinic acid (5-HPA) is a naturally occurring pyridine derivative endowed with notable antimicrobial activity and substantial pharmaceutical relevance. Despite its significance, the microbial catabolism of 5-HPA was not fully elucidated, especially in Gram-positive bacteria. In this study, we identified and characterized HppM, a novel NADH/FAD-dependent monooxygenase from <em>Rhodococcus rhodochrous</em>, which catalyzes the conversion of 5-HPA to 2,5-dihydroxypyridine (2,5-DHP). HppM shares approximately 38 % sequence identity with another 5-HPA monooxygenase from <em>Alcaligenes faecalis</em>. HppM exhibited strict substrate specificity for 5-HPA with an apparent <em>K</em>_m value of 121.7 μΜ, and showed no detectable activity against several structural analogs. AutoDock modeling identified Gln43 and His220 in catalysis, a prediction that was validated by site-directed mutagenesis: Ala substitutions at either position completely abolished activity. Bioinformatic surveys revealed that <em>hppM</em>, located within a gene cluster (<em>hpp</em>), is widely distributed across diverse Gram-positive genera, including <em>Dietzia</em>, <em>Janibacter</em>, <em>Mycobacterium</em>, and <em>Nesterenkonia</em>. These findings extend current understanding of microbial 5-HPA catabolic diversity and lay the groundwork for engineering of Gram-positive biocatalysts for 5-HPA degradation.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106286"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145974191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralization of 13C-labeled polyethylene by marine Bacillus velezensis MT9","authors":"Kejvin Bajo ,&nbsp;Boris Kolvenbach ,&nbsp;Philippe F.-X. Corvini ,&nbsp;Fabio Fava ,&nbsp;Noura Raddadi","doi":"10.1016/j.ibiod.2026.106294","DOIUrl":"10.1016/j.ibiod.2026.106294","url":null,"abstract":"<div><div>In the marine environment, plastic debris breaks down into smaller entities known as microplastics. Polyethylene (PE) is the main source of microplastics. In a previous study, we showed that marine <em>Bacillus</em> MT9 and <em>Vreelandella</em> strains (MT1, MT11) were able to degrade untreated PE based on SEM, gravimetric weight loss and FTIR analysis. In this study, we performed stable isotope tracing assays, measuring the production of ¹³CO₂ from ¹³C-PE powder (untreated or UV-treated) incubated with <em>B. velezensis</em> MT9, <em>V. titanicae</em> MT11 or <em>V. venusta</em> MT1 isolates under aerobic conditions in the presence and absence of yeast extract as co-nutrient source. Only <em>B. velezensis</em> MT9 exhibited mineralization activities towards untreated and UV-treated ¹³C-PE with the highest ¹³C-mass loss of 0.199% recorded for UV-treated ¹³C-PE with yeast extract, after 14 days incubation. In this study, we demonstrated the mineralization of ¹³C-PE by <em>B. velezensis</em> MT9. Furthermore, we also confirmed that photodegradation of plastic is a key process to enhance the biodegradation of PE. These findings suggest that <em>Bacillus</em> sp. could potentially degrade PE plastic waste in marine environment, as they can slowly mineralize PE even when other nutrients are present.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106294"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From macro-to microplastics: marine microalgae drive polystyrene degradation via EOM-mediated photochemical aging","authors":"Sufang Zhao ,&nbsp;Xuezhe Wen ,&nbsp;Haiming Xu ,&nbsp;Renju Liu ,&nbsp;Jiannan Wang ,&nbsp;Bin Zhi ,&nbsp;Xingyi Ma ,&nbsp;Zongze Shao","doi":"10.1016/j.ibiod.2026.106288","DOIUrl":"10.1016/j.ibiod.2026.106288","url":null,"abstract":"<div><div>The process of degradation and fragmentation of plastic into microplastics (MPs) by algae has been rarely addressed. Here we reported two marine algae capable of degrading polystyrene (PS) characterized as <em>Pseudochloris wilhelmii</em> K1 and <em>Jaaginema</em> sp. S1. Their PS degradation activity was confirmed by changes in plastic weight, chemical groups, and physical properties. K1 and S1 generated peak microplastic concentrations of 1.06 × 10⁷ and 2.23 × 10⁷ particles/L in light incubators, versus 7.33 × 10⁶ and 1.07 × 10⁷ particles/L under natural light. The results show that light exerted obvious influences on microplastic generation. The algal extracellular organic matter (EOM), particularly the humic acid-like fraction, significantly enhanced the photochemical aging of PS-MPs under natural sunlight irradiation. This aging process of MPs was predominantly mediated by reactive oxygen species (ROS) produced by marine algal EOM, leading to 3.3–3.8 % weight loss, MPs changes including increased oxygen-containing functional groups, and a significant reduction in particle size. Therefore, the widespread marine algae unprecedently participate in plastic degradation, fragmentation and aggregation, thereby interfering with the fate of plastic debris in marine environments.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106288"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145974192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low Density Polyethylene (LDPE) biodegradation efficiency of Bacillus pacificus SBAA07 isolated from Sundarbans mangrove sediments","authors":"Sumit Banerjee ,&nbsp;Subhajit Bisui ,&nbsp;Shidharth Sankar Ram ,&nbsp;Ivy Kanungo ,&nbsp;Anulipi Aich","doi":"10.1016/j.ibiod.2026.106287","DOIUrl":"10.1016/j.ibiod.2026.106287","url":null,"abstract":"<div><div>Low-Density Polyethylene (LDPE) contamination in the environment poses a significant ecological threat and harm to human health, prompting extensive research into effective remediation strategies using both chemical and biological approaches. Among these, bioremediation using bacterial species isolated from diverse habitats has shown considerable promise. Recent studies indicate that the microbiota of mangrove ecosystems, shaped by extreme and stressed environmental conditions, may exhibit enhanced plastic-degrading capabilities. This study aims to isolate and characterize potent LDPE-degrading bacteria from the unique stressed sediments of the Sundarbans mangrove forest, India. Unlike earlier studies that primarily screened microbes using conventional enrichment method, the present work employed a targeted screening strategy based on lipolytic activity to identify efficient LDPE-degrading bacteria. The strain <em>Bacillus pacificus</em> SBAA07 (NCBI accession number: PQ626050) was isolated and characterized during this study. Unlike terrestrial isolates which often require pretreatment this strain effectively colonizes and degrades LDPE films achieving a notable 13.08 % ± 0.01 dry weight reduction in 42 days without any pretreatment. The biodegradation mechanism was comprehensively investigated using multiple analytical techniques. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy suggests the oxidation of the polymer, showing the formation of carbonyl (1718 cm⁻¹) and hydroxyl groups. Raman spectroscopy further suggests possible biomolecular-like signature peaks associated with LDPE surface modifications on the treated film. Furthermore, a range of microscopic analyses using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) revealed a significant topographical alteration including the formation of pits, cracks, and extensive surface erosion on the treated films compared to the smoother control. AFM showed that root mean square roughness (Rq) of the treated film was increased by 99.8 %. These findings collectively highlight <em>Bacillus pacificus</em> SBAA07 as a promising microbial species for future plastic bioremediation strategies and underscoring mangrove ecosystems as a valuable source for novel biocatalysts.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106287"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145974193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Birnessite-assisted ecological adaptation of Sphingomonas HDJX-2 accelerates phenanthrene degradation in contaminated soils","authors":"Yaqi Jiao,&nbsp;Chunnan Zhou,&nbsp;Ying Yi,&nbsp;Junxin Jia,&nbsp;Hui Li,&nbsp;Qin Zhou","doi":"10.1016/j.ibiod.2026.106277","DOIUrl":"10.1016/j.ibiod.2026.106277","url":null,"abstract":"<div><div>Polycyclic aromatic hydrocarbons (PAHs), such as phenanthrene (PHE), pose a persistent threat to soil quality and ecological security. In this study, the remediation potential of a complex system consisting of <em>Sphingomonas</em> strain HDJX-2 and birnessite in PHE-contaminated soil was evaluated by conducting soil incubation experiments. The results demonstrated that the complex system achieved 80.86 % PHE removal efficiency within 35 days, significantly outperforming the single treatments and natural attenuation. The complex system significantly accelerated PHE degradation during the mid-incubation period (days 21–28). The increase in PHE degradation rate was accompanied by a temporary decrease in the total organic carbon, revealing a synergistic effect on pollutant mineralization. Enzyme activity assays revealed that the complex treatment significantly increased the activity of β-glucosidase and sucrase, promoting carbon cycling. High-throughput sequencing further demonstrated that the complex system not only reshaped the soil microbial community, but also significantly increased the relative abundance of functional degrading bacteria, such as <em>Sphingomonas</em>, <em>Arthrobacter</em>, and <em>Lysobacter</em>, while suppressing the stress-adapted bacteria, such as <em>Acidobacteria</em>. Notably, the birnessite likely facilitated the persistence and potential ecological establishment of <em>Sphingomonas</em> HDJX-2 in the soil, thereby increasing PAH degradation. LEfSe and redundancy analyses further validated the selective driving effect of the complex treatment system on functional microbial communities and key ecological processes. In summary, the HDJX-2–birnessite system not only accelerated PHE removal but also improved the structure of soil microbial community and carbon cycling, providing a practical strategy for efficient and sustainable bioremediation of PAH-contaminated soils.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106277"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145922624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disruption of the aggC gene enhances Shewanella oneidensis reductive transformation of a wide range of contaminants","authors":"Wei-Dong Li,&nbsp;Rachel Obeng,&nbsp;Yong Zhang,&nbsp;Luo Peng","doi":"10.1016/j.ibiod.2026.106297","DOIUrl":"10.1016/j.ibiod.2026.106297","url":null,"abstract":"<div><div>Microbes capable of extracellular electron transfer (EET) can detoxify oxidative contaminants via reductive transformations. Genetic engineering has been explored to enhance these processes, particularly by modifying EET pathways. This study investigates unexpected biological mechanisms that accelerate the reduction of oxidative contaminants. A transposon-insertion mutant library of <em>Shewanella oneidensis</em> was cultured with methyl orange (MO) as the sole electron acceptor (EA). Over successive transfers, MO reduction accelerated, and mutants with insertions in <em>aggC</em> became dominant. This gene has an important role in biofilm formation, which is not required in soluble EA reduction. A representative mutant, MO1, decolorized MO faster and grew more rapidly than the wild type (WT) and complemented strain (MO1-4318C). However, when cell density was standardized, MO reduction rates were comparable, indicating that MO1's faster decolorization was due to enhanced growth rather than increased intrinsic reduction activity. We propose that <em>aggC</em> disruption decreased intracellular cyclic di-GMP levels, which subsequently reduced biofilm-related biosynthesis, allocating more cellular resources to proliferation. Higher intracellular ATP levels in MO1 during MO-supported growth corroborated this hypothesis. When tested with other EAs supporting <em>Shewanella</em> growth (e.g., amaranth, anthraquinone-2,6-disulfonate, iron citrate), similar trends in growth rate, ATP content, and apparent EA reduction were observed, with MO1 outperforming the other strains. With contaminants acting as EAs but unable to support growth (e.g., naphthol green B, Cr(VI), nitrobenzene), MO1 maintained viability longer than WT and MO1-4318C, likely due to reduced ATP consumption from <em>aggC</em> disruption, resulting in faster pollutant biotransformation.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106297"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tide-triggered N2O emission dynamics in saltmarsh wetlands of the Yangtze Estuary: Significance of N2O consumption","authors":"Manping Zhang ,&nbsp;Chenchen Lixiang ,&nbsp;Jianli Wen ,&nbsp;Shanshan Sun ,&nbsp;Xushun Gu ,&nbsp;Shaoxuan Ding ,&nbsp;Shengbing He ,&nbsp;Guiling Liu","doi":"10.1016/j.ibiod.2026.106293","DOIUrl":"10.1016/j.ibiod.2026.106293","url":null,"abstract":"<div><div>Saltmarsh wetlands were significant sources of N₂O to the atmosphere; but the underlying mechanisms of N₂O emissions from saltmarsh sediments remained elusive. Here, the integrated methodology was utilized to reveal the primary microbial pathways responsible for N₂O emission in the Yangtze Estuary. The results indicated that heterotrophic denitrification (77.16–96.57 %) was the dominant pathway of N₂O production, while NH₂OH oxidation (1.10–6.78 %) and nitrifier denitrification (2.33–17.98 %) also had substantial contributions. The N₂O consumption proportions ranged from 63.69 % to 90.98 %, and its values were quietly pronounced, suggesting that N₂O emission contributed a small percentage of its gross production. The N₂O emission rates of <em>Phragmites australis</em> and <em>Spartina alterniflora</em> were lower than those of <em>Scirpus mariqueter</em> and bare mudflat, and showed a decreasing trend along the intertidal elevation gradient, with the values fluctuating from 6.01 to 27.07 g m⁻²·y⁻¹. Meanwhile, the N₂O emission rates were lower at flood tide than ebb tide. The microbial genera capable of N₂O metabolisms were annotated, such as <em>Nitrosomonas</em> and <em>Bacillus</em>, and nitrogen functional genes abundances were greatly positively correlated with nitrogen transformation rates, which significantly promoted N₂O dynamics. The absolute abundances of nitrogen functional genes varied from 3.22 × 10⁴ to 6.10 × 10⁸ copies·g⁻¹, and the potential rates of nitrification and dissimilatory nitrate reduction processes ranged from 5.07 to 236.96 nmolN₂·g⁻¹·d⁻¹. The variations in redox condition and carbon/nitrogen substrate availability were the crucial environmental factors influencing N₂O dynamics. Collectively, these findings could provide a valuable perspective on N₂O emissions, and recommend the significance of N₂O production and consumption in saltmarsh wetlands.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106293"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146073875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polystyrene biodegradation by Serratia marcescens isolated from a freshwater reservoir","authors":"İpek Çelen-Erdem ,&nbsp;Douglas G. Hayes ,&nbsp;Sadık Kalaycı ,&nbsp;Özge Karabıyık Acar ,&nbsp;Fikrettin Şahin","doi":"10.1016/j.ibiod.2026.106291","DOIUrl":"10.1016/j.ibiod.2026.106291","url":null,"abstract":"<div><div>Polystyrene (PS) is a persistent fossil fuel-based polymer that accumulates in freshwater systems, yet its microbial degradation in such environments remains insufficiently understood. In this study, freshwater bacteria were isolated from Palandöken Dam (Türkiye) and screened for their ability to degrade PS under controlled laboratory conditions. Among eleven bacterial isolates, <em>S</em>. <em>marcescens V9</em> exhibited the highest PS degradation efficiency under laboratory freshwater conditions. Quantitative analysis showed progressive PS weight losses of 5.5 %, 6.9 %, and 13.3 % after 30, 60, and 90 days, respectively. Scanning electron microscopy (SEM) confirmed biofilm formation and surface erosion, while attenuated total reflectance–Fourier (ATR-FTIR) transform infrared and thermogravimetric analyses (TGA) indicated the formation of new oxygenated functional groups and reduced thermal stability, respectively. Gel-permeation chromatography (GPC) revealed a 28–30 % reduction in both number- and weight-average molecular weights, reflecting polymer-chain scission. Mass balance calculations suggested partial conversion of PS carbon into biomass and oxidized products, although direct CO₂ evolution was not quantified and complete mineralization could not be confirmed. Collectively, these findings support an oxidative, biofilm-associated biodegradation mechanism and provide integrated evidence for PS depolymerization by a freshwater bacterial isolate, highlighting the potential role of <em>S. marcescens</em> V9 in environmentally relevant plastic degradation processes.</div></div>","PeriodicalId":13643,"journal":{"name":"International Biodeterioration & Biodegradation","volume":"209 ","pages":"Article 106291"},"PeriodicalIF":4.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146073962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}