International Biodeterioration & Biodegradation最新文献

Formation of biofilm fouling in filtration system based on immersed boundary method 基于浸入边界法的过滤系统生物膜污染的形成

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-16 DOI: 10.1016/j.ibiod.2026.106289

Yumeng Fu , Jiankun Wang , Xiaoling Wang

Biofilms are structured microbial communities formed by microorganisms (including bacteria, fungi, and other microbes) and their secreted extracellular polymeric substances (EPS), adhering to biotic or abiotic surfaces. In filtration system, biofilm formation can lead to filtration membrane clogging, water quality deterioration, equipment corrosion, and secondary pollution, among other issues. To investigate the formation and influencing factors of biofilm fouling in filtration system, we employed the immersed boundary method to simulate three typical clogging patterns: cake clogging, pore clogging, and streamer clogging. A systematic parametric analysis was conducted to elucidate the influence of key parameters, including fluid velocity, elastic modulus, channel spacing, and cell adhesion/detachment threshold, on streamer fouling formation. Our findings demonstrate that under conditions of higher fluid velocity, lower biofilm elastic modulus, and wider channel spacing, the length of streamer fouling is longer, the fluid flux is larger, and the capture efficiency of filter membrane is lower. Furthermore, we observed that the smaller the cell adhesion or detachment threshold, the more significant decline in capture efficiency, while the larger the detachment threshold, the more the flux decreases.

生物膜是由微生物（包括细菌、真菌和其他微生物）及其分泌的细胞外聚合物质（EPS）粘附在生物或非生物表面形成的结构化微生物群落。在过滤系统中，生物膜的形成会导致过滤膜堵塞、水质恶化、设备腐蚀、二次污染等问题。为了研究过滤系统中生物膜污染的形成及其影响因素，采用浸入边界法模拟了滤饼堵塞、孔隙堵塞和流线堵塞三种典型堵塞模式。通过系统的参数分析，阐明了流体速度、弹性模量、通道间距和细胞粘附/脱离阈值等关键参数对拖缆结垢形成的影响。研究结果表明，在流体流速较大、生物膜弹性模量较低、通道间距较宽的条件下，拖链污染的长度较长，流体通量较大，过滤膜的捕获效率较低。此外，我们观察到细胞粘附或脱离阈值越小，捕获效率下降越明显，而脱离阈值越大，通量下降越多。

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引用次数: 0

From macro-to microplastics: marine microalgae drive polystyrene degradation via EOM-mediated photochemical aging 从宏观到微塑料：海洋微藻通过eom介导的光化学老化驱动聚苯乙烯降解

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-13 DOI: 10.1016/j.ibiod.2026.106288

Sufang Zhao , Xuezhe Wen , Haiming Xu , Renju Liu , Jiannan Wang , Bin Zhi , Xingyi Ma , Zongze Shao

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 Pseudochloris wilhelmii K1 and Jaaginema 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.

藻类将塑料降解和破碎成微塑料（MPs）的过程很少得到解决。本文报道了两种能够降解聚苯乙烯（PS）的海藻，分别为Pseudochloris wilhelmii K1和Jaaginema sp. S1。塑料重量、化学基团和物理性质的变化证实了它们对PS的降解活性。K1和S1在光培养箱中产生的峰值微塑料浓度分别为1.06 × 107和2.23 × 107颗粒/L，而在自然光下产生的峰值微塑料浓度分别为7.33 × 106和1.07 × 107颗粒/L。结果表明，光对微塑料的产生有明显的影响。藻类细胞外有机物（EOM），特别是腐植酸样组分，在自然日光照射下显著促进PS-MPs光化学老化。这一老化过程主要由海藻EOM产生的活性氧（ROS）介导，导致MPs失重3.3 - 3.8%，MPs的变化包括含氧官能团的增加和粒径的显著减小。因此，广泛存在的海藻前所未有地参与了塑料的降解、破碎和聚集，从而干扰了海洋环境中塑料碎片的命运。

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引用次数: 0

Utilization of free and immobilised potent lipase-producing bacteria for dual fat-oil-grease (FOG) degradation and sesame butter wastewater treatment 游离和固定化强效脂肪酶产菌在油脂双重降解和芝麻油废水处理中的应用

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-13 DOI: 10.1016/j.ibiod.2026.106278

Cathbert Nomwesigwa , Mahmoud Nasr , Sameh Awad , Ahmed Abdel-Mawgood

This study investigated the efficiency of a novel polyvinyl alcohol-sodium alginate (PVA/SA) bead system for treating sesame butter wastewater (SBW) and concurrently producing bio-alkanes. The best two isolates were identified through 16S rRNA analysis and investigated as freely suspended individuals and in consortium treatments. The effect of bacterial immobilization on SBW detoxification was then investigated. Encapsulating Pseudomonas aeruginosa and Bacillus paramycoides within a sodium alginate (SA) matrix facilitated superior mass transfer of lipid globules (oleosomes), while ensuring high cell retention and protection against a harsh environment in the degradation system. Applying the PVA-SA composite yielded excellent results in successive degradation runs, i.e., up to 4 cycles. Analytical results from gas chromatography-mass spectrometry (GC-MS) justified the activation of the fatty aldehyde decarboxylase (FadD), fatty acyl-CoA reductase (Acr), and fatty aldehyde decarbonylase (CER1) enzymatic cascade. This activity resulted in the successful transformation of acyl groups into value-added hydrocarbons, specifically hexadecane and pentane. Detecting an m/z 115 peak (sodiated glycerol) served as a distinctive molecular marker for glycerol production. This SBW bacterial degradation achieved significant reductions in fat-oil-grease (FOG) = 95.18 ± 3.81 %, chemical oxygen demand = 89.96 ± 2.70 %, and total suspended solids = 86.15 ± 3.45 %. The current results demonstrate the significance of coupling industrial wastewater remediation with the sustainable synthesis of bio-based chemicals (e.g., hexadecane, dodecane, and pentane). Additional studies should validate the Pseudomonas aeruginosa and Bacillus paramycoides performance for FOG degradation under industrial-scale applications, further encouraging the private sectors to invest in the simultaneous remediation of high-strength lipid-rich effluents and the recovery of high-value chemical precursors.

研究了新型聚乙烯醇-海藻酸钠（PVA/SA）体系处理芝麻油废水并同时生产生物烷烃的效率。通过16S rRNA分析鉴定出两株最佳分离菌株，并将其作为自由悬浮个体和联合处理进行研究。然后研究了细菌固定化对SBW解毒的影响。在海藻酸钠（SA）基质中封装铜绿假单胞菌和副双亲芽孢杆菌有助于脂球（脂质体）的优良传质，同时确保高细胞保留率和对降解系统中恶劣环境的保护。应用PVA-SA复合材料在连续降解运行中取得了优异的效果，即多达4个循环。气相色谱-质谱（GC-MS）分析结果证实了脂肪酸醛脱羧酶（FadD）、脂肪酸酰基辅酶a还原酶（Acr）和脂肪酸醛脱羧酶（CER1）酶级联的激活。这种活性导致酰基成功转化为增值碳氢化合物，特别是十六烷和戊烷。检测m/ z115峰（钠化甘油）作为甘油生产的独特分子标记。SBW细菌降解后，脂肪-油脂（FOG）降低95.18±3.81%，化学需氧量降低89.96±2.70%，总悬浮物降低86.15±3.45%。目前的研究结果表明，将工业废水修复与生物基化学品（如十六烷、十二烷和戊烷）的可持续合成相结合具有重要意义。进一步的研究应验证铜绿假单胞菌和副芽孢杆菌在工业规模应用下降解FOG的性能，进一步鼓励私营部门投资于同时修复高强度富脂废水和回收高价值化学前体。

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引用次数: 0

Low Density Polyethylene (LDPE) biodegradation efficiency of Bacillus pacificus SBAA07 isolated from Sundarbans mangrove sediments 孙德尔本斯红树林沉积物中分离的太平洋芽孢杆菌SBAA07低密度聚乙烯（LDPE）生物降解效率

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-12 DOI: 10.1016/j.ibiod.2026.106287

Sumit Banerjee , Subhajit Bisui , Shidharth Sankar Ram , Ivy Kanungo , Anulipi Aich

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 Bacillus pacificus 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 Bacillus pacificus SBAA07 as a promising microbial species for future plastic bioremediation strategies and underscoring mangrove ecosystems as a valuable source for novel biocatalysts.

环境中的低密度聚乙烯（LDPE）污染对人类健康造成了重大的生态威胁和危害，促使人们广泛研究利用化学和生物方法有效修复策略。其中，利用从不同生境中分离出来的细菌物种进行生物修复已显示出相当大的前景。最近的研究表明，受极端和压力环境条件影响，红树林生态系统的微生物群可能表现出增强的塑料降解能力。本研究旨在从印度孙德尔本斯红树林独特的应激沉积物中分离和表征有效的ldpe降解细菌。与早期主要使用传统富集方法筛选微生物的研究不同，本研究采用基于脂溶活性的靶向筛选策略来鉴定高效的ldpe降解细菌。本研究分离并鉴定了一株太平洋芽孢杆菌SBAA07 （NCBI登录号：PQ626050）。与通常需要预处理的陆生菌株不同，该菌株可以有效地定殖并降解LDPE膜，无需任何预处理，在42天内显著减少13.08%±0.01的干重。采用多种分析技术对其生物降解机理进行了全面研究。衰减全反射-傅里叶变换红外光谱（ATR-FTIR）表明聚合物氧化，显示羰基（1718 cm−1）和羟基的形成。拉曼光谱进一步表明，处理后的薄膜上可能存在与LDPE表面修饰相关的生物分子样特征峰。此外，使用原子力显微镜（AFM）和扫描电子显微镜（SEM）进行的一系列微观分析显示，与平滑控制相比，处理后的薄膜上出现了显著的地形变化，包括凹坑、裂缝的形成和广泛的表面侵蚀。AFM结果表明，处理后的膜的均方根粗糙度（Rq）提高了99.8%。这些发现共同强调了太平洋芽孢杆菌SBAA07是未来塑料生物修复策略的一个有前途的微生物物种，并强调了红树林生态系统是新型生物催化剂的宝贵来源。

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引用次数: 0

Identification and characterization of a novel monooxygenase for 5-hydroxypicolinic acid degradation in gram-positive bacteria 一种在革兰氏阳性菌中降解5-羟基喹啉酸的新型单加氧酶的鉴定和表征

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-11 DOI: 10.1016/j.ibiod.2026.106286

Qimiao Xu , Fuyu Song , Yinhu Jiang , Ye Song , Qi Zhao , Jian He , Lingling Zhao , Jiguo Qiu

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 Rhodococcus rhodochrous, 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 Alcaligenes faecalis. HppM exhibited strict substrate specificity for 5-HPA with an apparent K_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 hppM, located within a gene cluster (hpp), is widely distributed across diverse Gram-positive genera, including Dietzia, Janibacter, Mycobacterium, and Nesterenkonia. 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.

5-羟基吡啶酸（5-HPA）是一种天然存在的吡啶衍生物，具有显著的抗菌活性和重要的药学意义。尽管具有重要意义，但5-HPA的微生物分解代谢尚未完全阐明，特别是在革兰氏阳性细菌中。在这项研究中，我们鉴定并表征了HppM，这是一种新的NADH/ fad依赖的单加氧酶，来自Rhodococcus rhodochrous，它催化5-HPA转化为2,5-二羟基吡啶（2,5- dhp）。HppM与来自粪碱性菌的另一种5-HPA单加氧酶的序列相似性约为38%。HppM对5-HPA具有严格的底物特异性，表观Km值为121.7 μΜ，对几种结构类似物没有检测到活性。AutoDock模型鉴定出Gln43和His220具有催化作用，这一预测通过位点定向诱变得到了验证：任何位置的Ala取代都完全消除了活性。生物信息学调查显示，hppM位于一个基因簇（hpp）内，广泛分布于不同的革兰氏阳性属，包括Dietzia、Janibacter、Mycobacterium和nesterenkoia。这些发现扩展了目前对微生物5-HPA分解代谢多样性的理解，并为革兰氏阳性生物催化剂的5-HPA降解工程奠定了基础。

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引用次数: 0

Birnessite-assisted ecological adaptation of Sphingomonas HDJX-2 accelerates phenanthrene degradation in contaminated soils 石辅助的鞘单胞菌HDJX-2的生态适应加速了污染土壤中菲的降解

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-07 DOI: 10.1016/j.ibiod.2026.106277

Yaqi Jiao, Chunnan Zhou, Ying Yi, Junxin Jia, Hui Li, Qin Zhou

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 Sphingomonas 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 Sphingomonas, Arthrobacter, and Lysobacter, while suppressing the stress-adapted bacteria, such as Acidobacteria. Notably, the birnessite likely facilitated the persistence and potential ecological establishment of Sphingomonas 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.

多环芳烃（PAHs），如菲（PHE），对土壤质量和生态安全构成持续威胁。本研究通过土壤培养实验，评价由鞘氨单胞菌HDJX-2和碧玉矿组成的复合系统对ph污染土壤的修复潜力。结果表明，复合系统在35 d内的PHE去除率达到80.86%，显著优于单一处理和自然衰减。在孵育中期（21-28天），复合系统显著加速了PHE的降解。PHE降解速率的增加伴随着总有机碳的暂时减少，显示出对污染物矿化的协同效应。酶活性测定表明，复合处理显著提高了β-葡萄糖苷酶和蔗糖酶的活性，促进了碳循环。高通量测序进一步证明，该复杂系统不仅重塑了土壤微生物群落，而且显著增加了功能性降解细菌（如鞘单胞菌、节杆菌和溶菌）的相对丰度，同时抑制了应激适应细菌（如酸杆菌）的相对丰度。值得注意的是，碧玉可能促进了鞘氨单胞菌HDJX-2在土壤中的持久性和潜在的生态建立，从而增加了PAH的降解。LEfSe和冗余分析进一步验证了复合处理系统对功能微生物群落和关键生态过程的选择性驱动作用。综上所述，HDJX-2-birnessite体系不仅加速了PHE的去除，而且改善了土壤微生物群落结构和碳循环，为有效和可持续地修复多环芳烃污染土壤提供了可行的策略。

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引用次数: 0

Synergistic degradation of polycyclic aromatic hydrocarbons by Fusarium and Priestia in saline environments: From kinetic characterization to multi-omics dissection 盐渍环境中镰刀菌和镰刀菌协同降解多环芳烃：从动力学表征到多组学解剖

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-07 DOI: 10.1016/j.ibiod.2026.106279

Fenglei Han , Zhoutong Liu , Xiuxia Zhang , Fan Yang , Biao Wang , Feng Yao , De Li , Kang Xiong , Lihan Ren

This study addresses the challenges of low bioavailability and restricted degradation efficiency of polycyclic aromatic hydrocarbons in saline environments by isolating the fungus Fusarium FG and the bacterium Priestia BT1 from saline contaminated soil in Dagang Oilfield, Tianjin. A fungi-bacteria FG-BT1 (FB) consortium was constructed and evaluated for its synergistic degradation performance using pyrene as a model pollutant. Under 3 % salinity and 50 mg/L pyrene, the FB consortium achieved a degradation rate of 41.98 % within 10 days, significantly higher than individual strains. The consortium also exhibited broad-spectrum effects on phenanthrene and naphthalene. Adsorption-degradation kinetics showed that the consortium followed the pseudo-second-order adsorption model and the Monod degradation model. Genomic analysis revealed complementary metabolic pathways in BT1 and FG, forming a cross-metabolic network. Untargeted metabolomics identified key products and intermediates, including 1-hydroxypyrene, 1,2-naphthoquinone, phthalic acid, and protocatechuic acid, and emphasized the role of DGTS-type biosurfactants and 12-O-D-Glucuronoside-13-Hydroxyoctadec-9Z-Enoate in enhancing pollutant solubility and transmembrane transport. Future research will focus on soil simulation remediation experiments to assess the consortium's performance in real-world conditions and explore its potential integration with existing chemical treatment technologies for more efficient and sustainable remediation strategies.

本研究通过从天津大港油田盐渍污染土壤中分离出镰刀菌FG和Priestia BT1，解决了盐渍环境中多环芳烃生物利用度低和降解效率受限的问题。以芘为模型污染物，构建了真菌-细菌FG-BT1 （FB）联合体，并对其协同降解性能进行了评价。在3%盐度和50 mg/L芘条件下，FB菌群在10 d内的降解率达到41.98%，显著高于单个菌株。对菲和萘也表现出广谱效应。吸附-降解动力学表明，该联合体符合准二级吸附模型和Monod降解模型。基因组分析显示BT1和FG的代谢途径互补，形成交叉代谢网络。非靶向代谢组学鉴定了关键产物和中间体，包括1-羟基芘、1,2-萘醌、邻苯二甲酸和原儿茶酸，并强调了dgts型生物表面活性剂和12- o - d -葡糖苷-13-羟基十八烷基- 9z - enoate在提高污染物溶解度和跨膜运输中的作用。未来的研究将集中在土壤模拟修复实验上，以评估该联盟在现实条件下的表现，并探索其与现有化学处理技术的潜在整合，以实现更有效和可持续的修复策略。

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引用次数: 0

Biological treatment of sulfate-laden acidic wastewater in a semi-batch reactor: Performance optimization and microbial community dynamics 半间歇反应器处理含硫酸盐酸性废水：性能优化和微生物群落动态

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2026-01-03 DOI: 10.1016/j.ibiod.2026.106276

Sreekanth Yadav Golla , Guntakala Venkatanaga Chandra , Pranab Kumar Ghosh

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

COD / {SO}_{4}^{2 ‐}

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

COD / {SO}_{4}^{2 ‐}

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 Desulfobacterota (Desulfovibrio genus), 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.

工业和采矿活动产生的含硫酸盐酸性废水因其不利影响而受到全球关注。为了解决这一问题，我们在实验规模的硫化半间歇反应器（SmBR）上接种了混合细菌培养物，运行了281天，以评估硫酸盐（500-4500 mg/L）和酸性条件（pH 6.0-1.85）对硫酸盐去除和微生物群落的影响。最佳COD/SO42‐比和HRT分别为0.7和4 d。SmBR在进水硫酸盐浓度为4500 mg/L、COD/SO42 -比值为0.7的情况下，硫酸盐和COD去除率分别为80%和87%，出水pH从2.0提高到7.2。进一步降低进料pH至1.85，导致反应器性能急剧下降，通过调整操作条件，在30天内恢复。乳酸还原到硫酸盐还原的电子流在86% ~ 91%之间变化，表明底物的有效利用。16S rRNA测序显示，进水pH从6.0降至2.5导致微生物多样性向SRB的一个特殊群体转移，特别是Desulfovibrio属（desulfoobacterota），从12%增加到45%，强调了它们在硫酸盐去除中的关键作用。在SmBR中开发的混合细菌培养物可用于处理酸性矿山废水、铅酸蓄电池生产废水、二次炼铅厂废水等含硫酸盐的工业酸性废水。本研究结果为处理含硫酸盐酸性废水提供了一种可持续的生物修复方法。

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引用次数: 0

Biofilm-mediated mitigation of nitrous oxide emissions in anammox-based wastewater treatment 生物膜介导的厌氧氨氧化废水处理中氧化亚氮排放的减缓

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2025-12-31 DOI: 10.1016/j.ibiod.2025.106274

Zhiman Lin , Jinfan Zhang , Ru Wang , Jingmin Ou , He Zhang , Zihua Wang , Fangyuan Zheng , Xiantao Sun , Xin Wei , Yiming Huang , Zhenguo Chen , Mark C.M. van Loosdrecht , Yuchun Yang

Wastewater treatment is a major source of global greenhouse gas (GHG) emissions, largely driven by nitrous oxide (N₂O) release during nitrogen removal processes. While anaerobic ammonium-oxidizing (anammox) bacteria have become widely adopted to optimize nitrogen removal, the pathways governing N₂O emissions in anammox systems remain insufficiently characterized. Findings revealed that in aerobic environments with low dissolved oxygen, nitrifying microorganisms showed pronounced upregulation of N₂O synthesis genes, confirming their pivotal role in emissions. Conversely, heterotrophic denitrification dominated N₂O production in anaerobic systems. Crucially, anammox-dominated biofilms displayed substantially lower expression of N₂O-related genes compared to suspended sludge, suggesting reduced emission risks in biofilm configurations. Batch experiments demonstrated a 2.78-fold lower N₂O release from biofilms than suspended biomass. This mitigation was linked to restricted substrate transport within biofilms, which curbed NO₂⁻ buildup and subsequently suppressed nitrifier-derived N₂O formation. Additionally, the high-density colonization of anammox bacteria in biofilms efficient scavenging of nitric oxide (NO) and hydroxylamine (NH₂OH), critical intermediates in N₂O synthesis. Employing an integrated multi-omics approach, this study investigates N₂O production and consumption pathways in diverse anammox systems and unveils the N₂O mitigation mechanisms of biofilms, offering fundamental insights for reducing N₂O emissions in wastewater treatment.

废水处理是全球温室气体（GHG）排放的主要来源，主要由氮去除过程中氧化亚氮（N2O）的释放驱动。虽然厌氧氨氧化（anammox）细菌已被广泛应用于优化氮去除，但在厌氧氨氧化系统中控制N2O排放的途径仍然缺乏充分的表征。研究结果表明，在低溶解氧的好氧环境中，硝化微生物的N2O合成基因明显上调，证实了它们在排放中的关键作用。相反，异养反硝化作用在厌氧系统中主导N2O的产生。关键是，厌氧氨氧化主导的生物膜与悬浮污泥相比，n2o相关基因的表达显著降低，这表明生物膜配置降低了排放风险。批量实验表明，生物膜的N2O释放量比悬浮生物质低2.78倍。这种缓解与生物膜内受限的底物运输有关，这抑制了NO2−的积累，随后抑制了硝化菌衍生的N2O的形成。此外，厌氧氨氧化菌在生物膜中的高密度定植可以有效清除一氧化氮（NO）和羟胺（NH2OH），这是合成N2O的关键中间体。本研究采用综合多组学方法，研究了不同厌氧氨氧化系统中N2O的产生和消耗途径，揭示了生物膜的N2O减缓机制，为减少废水处理中N2O的排放提供了基础见解。

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引用次数: 0

Exploring calcium carbonate biomineralization by yeasts isolated from cement-associated environments 从水泥相关环境中分离的酵母探索碳酸钙生物矿化

IF 4.1 2区环境科学与生态学 Q2 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

International Biodeterioration & Biodegradation

Pub Date : 2025-12-31 DOI: 10.1016/j.ibiod.2025.106275

Giovana Manzini , Giuseppe Ciaramella Moita , Romildo Dias Toledo Filho , Eliana Flávia Camporese Sérvulo , Vitor Liduino

This study advances microbial-induced calcium carbonate precipitation (MICP), a technology with potential to mitigate carbon emissions. A composite mixture of natural and recycled stone aggregates was tested for the isolation of carbonate-forming fungi, seeking to explore alternative eukaryotic microorganisms capable of MICP. Three yeast and seven mold cultures were isolated. The yeast isolates, identified through ITS sequencing as Candida orthopsilosis, Naganishia sp., and Rhodotorula mucilaginosa, were evaluated for their ability to produce CaCO₃ in an acetate-based medium over a 7-day cultivation period. All three yeasts generated mineral residues, showing different overall yields (ranging from 0.6 to 1.6 g) but with similar carbonate contents (∼20 % as CaCO₃). Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of carbonate groups in all mineralized residues. At the same time, thermogravimetric (TG-DTG) analyses revealed that among the isolates, R. mucilaginosa achieved the highest conversion rate of calcium acetate to CaCO₃ (48.8 ± 3.1 %), corresponding to a precipitation yield of 0.29 g CaCO₃, more than twice that obtained for the other isolates. X-ray diffraction (XRD) analyses revealed that the only CaCO₃ polymorph formed was vaterite. These findings provide new insights into the biomineralization capacity of non-ureolytic yeasts and highlight their potential applicability as alternative biocatalysts in MICP-based technologies.

这项研究推进了微生物诱导碳酸钙沉淀（MICP）技术，这是一项有潜力减少碳排放的技术。测试了天然和再生石材骨料的复合混合物，以分离碳酸盐形成真菌，寻求探索能够MICP的替代真核微生物。分离出3个酵母培养物和7个霉菌培养物。通过ITS测序鉴定，分离的酵母菌分别为念珠菌（Candida orthopsilosis）、Naganishia sp.和粘液红酵母（Rhodotorula mucilaginosa），并对它们在醋酸盐培养基中产生CaCO3的能力进行了评估，培养周期为7天。所有三种酵母产生的矿物残留物，显示出不同的总产量（从0.6到1.6 g不等），但碳酸盐含量相似（约为CaCO3的20%）。傅里叶变换红外光谱（FTIR）证实了所有矿化残留物中碳酸盐基团的存在。同时，热重分析（TG-DTG）结果表明，在所有菌株中，粘胶菌的醋酸钙转化率最高（48.8±3.1%），相当于CaCO3的沉淀产率为0.29 g，是其他菌株的2倍以上。x射线衍射（XRD）分析表明，CaCO3形成的唯一多晶是水晶石。这些发现为非解尿酵母菌的生物矿化能力提供了新的见解，并强调了它们作为基于micp技术的替代生物催化剂的潜在适用性。

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引用次数: 0