Search Results (30,308)

Well integrity is paramount for the safe, environmentally responsible, and economically viable operation of wells throughout their lifecycle, encompassing conventional oil and gas production, unconventional resource extraction (e.g., shale gas and tight oil), and geological storage applications (CO₂, H₂, and natural gas). This review presents a comprehensive synthesis of well integrity challenges, failure mechanisms, monitoring technologies, and management strategies across these operational domains. Key integrity threats—including cement sheath degradation (chemical attack, debonding, cracking, microannuli), casing failures (corrosion, collapse, burst, buckling, fatigue, wear, and connection damage), sustained casing pressure (SCP), and wellhead leaks—are examined in detail. Unique challenges posed by hydraulic fracturing in unconventional wells and emerging risks in CO₂ and hydrogen storage, such as corrosion, carbonation, embrittlement, hydrogen-induced cracking (HIC), and microbial degradation, are also highlighted. The review further explores the evolution of integrity standards (NORSOK, API, ISO), the implementation of Well Integrity Management Systems (WIMS), and the integration of advanced monitoring technologies such as fiber optics, logging tools, and real-time pressure sensing. Particular emphasis is placed on the role of digital technologies—including artificial intelligence, machine learning, and digital twin systems—in enabling predictive maintenance, early failure detection, and lifecycle risk management. The novelty of this review lies in its integrated, cross-domain perspective and its emphasis on digital twin applications for continuous, adaptive well integrity surveillance. It identifies critical knowledge gaps in modeling, materials qualification, and data integration—especially in the context of long-term CO₂ and H₂ storage—and advocates for a proactive, digitally enabled approach to lifecycle well integrity. Full article

Mutations in the CFTR genes causing cystic fibrosis (CF) are associated with the presence of thick, viscous mucus and the formation of biofilms in the gastrointestinal tract (GI) that impair intestinal homeostasis, triggering chronic inflammation, epithelial barrier dysfunction, and changes in the composition and activity of the gut microbiota. CFTR protein modulators represent a promising approach to enhancing lower GI function in patients with CF. The aim of the review is to present the complex relationships between the presence of CFTR gene mutations and the gut microbiota dysbiosis in patients with cystic fibrosis. Mutations in the CFTR gene, the molecular basis of cystic fibrosis (CF), disrupt epithelial ion transport and profoundly alter the gastrointestinal environment. Defective chloride and bicarbonate secretion leads to dehydration of the mucosal layer, increased mucus viscosity, and the formation of biofilms that favour microbial persistence, which together promote gut microbiota dysbiosis. This dysbiotic state contributes to impaired epithelial barrier function, chronic intestinal inflammation, and abnormal immune activation, thereby reinforcing disease progression. The interplay between CFTR dysfunction and microbial imbalance appears to be bidirectional, as dysbiosis may further exacerbate epithelial stress and inflammatory signalling. Therapeutic interventions with CFTR protein modulators offer the potential to partially restore epithelial physiology, improve mucus hydration, and foster a microbial milieu more consistent with intestinal homeostasis. The aim of this review is to elucidate the complex relationships between CFTR gene mutations and gut microbiota dysbiosis in patients with cystic fibrosis, with a particular emphasis on the clinical implications of these interactions and their potential to inform novel therapeutic strategies. Full article

As a consequence of global climate change, lakes are increasingly receiving terrestrial dissolved organic carbon (DOC), which serves as a key substrate for microbial metabolism and fuels bacterial production (BP). However, bacteria in aquatic systems play a dual role in the carbon cycle by not only incorporating DOC into their biomass but also respiring it as CO₂ into the atmosphere (bacterial respiration, BR). As such, the estimation of bacterial growth efficiency (BGE), defined as BP/(BP + BR), is critical for understanding lake carbon dynamics and bacterial carbon processing. To investigate the effects of terrestrial organic carbon on bacterial carbon processing in lakes, we conducted a ¹³C-labeling experiment utilizing three microcosms, each filled with 0.22 μm filtered lake water inoculated with a microbial inoculum and set as follows: no extra DOC addition as a control, adding phytoplankton-derived DOC, and adding a mixture of phytoplankton-derived and terrestrial DOC. Our findings revealed that the addition of terrestrial DOC significantly enhanced both overall BGE (40.0%) and specific BGE based on phytoplankton-DOC (62.3%) and indigenous lake DOC (27.0%). Furthermore, terrestrial DOC inputs also altered bacterial carbon consumption pathways, as indicated by isotopic evidence. These results suggest that the input of terrestrial DOC may significantly affect lake DOC processing by changing the way bacteria process phytoplankton-DOC and indigenous lake DOC. This study highlights the profound influence of terrestrial DOC on lake carbon processing and suggests that terrestrial–aquatic cross-ecosystem interactions are critical for understanding lake carbon dynamics under changing climatic conditions. Full article

Terephthalic acid (TPA), a major monomer of polyethylene terephthalate (PET), represents a significant challenge in plastic waste management due to its persistence in the environment. In this study, we report a newly developed bacterial consortium capable of using TPA as the sole carbon source in a defined mineral medium. The consortium achieved stationary phase within five days and metabolized approximately 85% of the available TPA. Metabolite analysis by high-performance liquid chromatography (HPLC) and liquid chromatography tandem mass spectrometry (LC-MS/MS) revealed the activation of the benzoate degradation pathway during TPA catabolism. Additionally, the consortium secreted commercially relevant metabolites such as cis,cis-muconic acid and catechol into the culture medium. Genetic profiling using a reverse transcription quantitative polymerase chain reaction (RT-qPCR) and 16S rRNA sequencing identified Paraburkholderia fungorum as the dominant species, suggesting it plays a key role in TPA degradation. The ability of this microbial community to efficiently convert TPA into high-value by-products offers a promising and potentially economically sustainable approach to addressing plastic pollution. Full article

Chitosanases are glycoside hydrolases (GHs) that catalyze the endo- or exo-type cleavage of β-1,4-glycosidic linkages in chitosan, enabling the selective production of chitooligosaccharides (COSs) with well-defined structures and diverse bioactivities. Owing to their substrate specificity and environmentally friendly catalytic action, chitosanases have garnered increasing attention as sustainable biocatalysts for COS production, with broad application potential in agriculture, food, medicine, and cosmetics. This review provides a comprehensive overview of recent advances in chitosanase research, focusing on the catalytic mechanisms and structure–function relationships that govern substrate selectivity and functional divergence across different GH families. Microbial diversity and heterologous expression systems for chitosanase production are discussed in parallel with biochemical characterization to support the rational selection of enzymes for specific biotechnological applications. Advances in protein engineering and computational approaches are highlighted as strategies to improve catalytic efficiency, substrate range, and stability. In addition, bioprocess optimization is addressed, with emphasis on fermentation using low-cost substrates and the application of immobilized enzymes and nano-biocatalyst systems for green and efficient COS production. Summarizing and discussing previous findings are essential to support future research and facilitate the development of next-generation chitosanases for sustainable industrial use. Full article

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants composed of two or more fused benzene rings, posing serious threats to ecological environments and human health. Biodegradation is an efficient, economical, and sustainable approach for remediating PAHs pollution. In our previous work, we isolated and characterized a PAH-degrading bacterium, Burkholderia sp. FM-2. FM-2 demonstrated strong tolerance and efficient degradation capacity toward various PAHs, achieving 81.98% degradation of 2 mM phenanthrene within 3 days, and over 58% degradation of 2 mM fluorene, dibenzofuran, and dibenzothiophene under the same conditions. Through combined genomic and transcriptomic analyses, a putative PAH degradation gene cluster was identified in the FM-2 genome. Phylogenetic and domain architecture analyses were conducted on seven oxygenase genes within the cluster. Using AlphaFold 3, we predicted the three-dimensional structure of the downstream transport protein OmpW and proposed a potential transmembrane channel for PAHs uptake. To eliminate the phenanthrene degradation intermediate 1-hydroxy-2-naphthoic acid, a genetically engineered strain FM-2::nahG was constructed by heterologous expression of the salicylate hydroxylase gene (nahG). The modified strain completely abolished the accumulation of 1-hydroxy-2-naphthoic acid and achieved complete mineralization of phenanthrene. This study not only reveals the molecular basis of PAHs degradation in Burkholderia sp. FM-2 but also demonstrates the potential of metabolic engineering to enhance biodegradation ability, providing a promising microbial candidate for the bioremediation of PAH-polluted environments. Full article

The increasing incidence of hospital-acquired infections and antimicrobial-resistant pathogens poses a major clinical challenge. Nearly all medical devices are vulnerable to bacterial biofilm formation, which acts as a protective coating against the host defense systems and antibiotics. The persistence of biofilm infections, accounting for around 65% of all microbial infections, and poor conventional treatment outcomes has driven interest in alternative approaches like bacteriophage therapy. This review encompasses key aspects of biofilm biology, taking into account the clinically significant ESKAPE pathogens, and provides an in-depth analysis of the role of phage agents in biofilm control as a new biofilm control strategy. Diving deeper into the mechanisms of phage-mediated processes, the review examines how bacteriophages penetrate and disrupt biofilm architecture and evaluates current therapeutic strategies that exploit these actions, acknowledging their limitations and considering possible future directions. Full article

The severe damage caused by the fall webworm Hyphantria cunea is closely related to its internal microbiota. However, due to the widespread use of antibiotics and their environmental persistence, the specific effects of various antibiotics on the microbiome and fitness of H. cunea larvae remain ambiguous. This study investigated the impacts of three antibiotics (tetracycline, rifampicin, and kanamycin) on microbiome assembly, functional traits, and host fitness. Our findings revealed that each antibiotic distinctly altered the microbial community: tetracycline primarily decreased bacterial diversity (e.g., reduced abundance of Actinomycetota) and suppressed host fecundity; kanamycin lowered microbial evenness (e.g., decreased Bacillota) and diminished pupal weight; whereas rifampicin significantly restructured the community (e.g., increased Pseudomonas and decreased Bacillota), enhanced functional traits such as biofilm formation and stress tolerance, and imposed multidimensional adverse effects on fitness (prolonged developmental duration, reduced pupal weight, and decreased hatching rate). Alterations in microbiome diversity, structure, and function were tightly correlated with the differential impacts of antibiotics on host fitness. This research elucidates the mechanisms by which antibiotics disrupt host–microbe interactions in H. cunea, offering a theoretical foundation for understanding antibiotic ecological repercussions and devising microbe-based green pest control strategies. Full article

Background/Objectives: Probiotic interventions can alleviate gastrointestinal (GI) discomfort, but evidence comparing multi-strain combinations at different doses remains limited. We evaluated whether formulation potency influences clinical and microbiome outcomes. Methods: In a 4-week, randomized, double-blind trial, 100 eligible adults received one of two higher-dose multi-strain probiotic formulations at different dosages (Wec120B vs Wec300B). Weekly Gastrointestinal Symptom Rating Scale (GSRS) scores tracked symptom trajectories. Gut microbiota composition and diversity were profiled by 16S rRNA gene sequencing. Biomarkers included lipopolysaccharide (LPS), fecal calprotectin (FC), and immunoglobulin A (IgA). Results: Results indicated that the Wec120B group showed more significant improvement in abdominal pain during the early phase of intervention, while the Wec300B group was more effective in relieving reflux symptoms. In terms of biomarkers, Wec120B was more effective in reducing lipopolysaccharide (LPS) levels, whereas Wec300B showed a greater increase in immunoglobulin A (IgA) and a more pronounced reduction in fecal calprotectin (FC) levels. Both formulations significantly increased the abundance of beneficial genera such as Bifidobacterium, Blautia, [Eubacterium]_hallii_group, and Anaerostipes, while suppressing the growth of potential pathogens including Prevotella and Escherichia-Shigella. Conclusions: These findings suggest that both compound probiotic products can significantly improve GI symptoms and modulate gut microbiota structure, with Wec300B showing a superior performance in microbial regulation, likely due to its higher dosage of probiotics. This study provides reference evidence for the rational application of probiotic products in gut health management. Full article

Lop Nur, an extremely arid environment, harbors unique microbial resources and represents a potential reservoir for novel bioactive substances. With antibiotic resistance becoming an increasing global concern, the resistance traits of microorganisms in extreme habitats and their potential association with antibacterial activity remain poorly understood. This study aimed to investigate the diversity of soil microorganisms in Lop Nur, their resistance to norfloxacin, kanamycin, and amoxicillin, and their inhibitory activity against common pathogenic bacteria, thereby providing a scientific basis for the discovery of new antibacterial candidates. Surface soils from three sampling points in Lop Nur were inoculated onto Gao’s No.1 and LB media supplemented with different antibiotic regimens (single, pairwise, and triple combinations). Isolates were identified by 16S rRNA gene sequencing, their antibiotic resistance was assessed using the disk diffusion method, and antibacterial activity was evaluated using the agar well diffusion method. A total of 120 microorganisms were isolated, belonging to six phyla and nine genera, including 10 potential new species. The control group yielded the highest diversity (35 strains), whereas only 4 strains were recovered under triple-antibiotic treatment, demonstrating the strong selective effect of antibiotic stress. Resistance profiling showed that 88.14% of strains were resistant to amoxicillin, 64.71% to norfloxacin, and 60.68% to kanamycin, with multidrug resistance being widespread. Eleven strains exhibited antibacterial activity against five pathogens, including Staphylococcus aureus (maximum inhibition zone 53.51 mm), and nine of these strains also displayed antibiotic resistance, suggesting a potential association between resistance and antibacterial activity. Microorganisms isolated from Lop Nur displayed extensive resistance and notable antibacterial activity. Antibiotic stress strongly influenced the cultivable microbial isolates, facilitating the recovery of resistant strains with antibacterial potential. These findings provide a valuable reference for exploring microbial resources in extreme environments and highlight the potential link between antibiotic resistance and antibacterial activity. Full article

The holobiont paradigm, conceptualizing host–microbiome assemblages as functionally integrated entities, has fundamentally altered interpretations of adaptive responses to environmental pressures spanning multiple organizational levels. This review synthesizes the current knowledge on microbiome-host coevolution, focusing on three key aspects. First, it examines the evolutionary origins of holobionts from primordial microbial consortia. Second, it considers the mechanistic basis of microbiome-mediated stress resilience in plants and animals. Finally, it explores the ecological implications of inter-holobiont interactions. We highlight how early microbial alliances (protomicrobiomes) laid the groundwork for eukaryotic complexity through metabolic cooperation, with modern holobionts retaining this plasticity to confront abiotic and biotic stressors. In plants, compartment-specific microbiomes (e.g., rhizosphere, phyllosphere) enhance drought tolerance or nutrient acquisition, while in animals, the gut microbiome modulates neuroendocrine and immune functions via multi-organ axes (gut–brain, gut–liver, etc.). Critically, we emphasize the role of microbial metabolites (e.g., short-chain fatty acids, VOCs) as universal signaling molecules that coordinate holobiont responses to environmental change. Emerging strategies, like microbiome engineering and probiotics, are discussed as tools to augment stress resilience in agriculture and medicine. By framing adaptation as a collective trait of the holobiont, this work bridges evolutionary biology, microbiology, and ecology to offer a unified perspective on stress biology. Full article

This study discussed the influence of acetate and sodium chloride concentration on monitoring 2,4-dichlorophenol(2,4-DCP) by electroactive bacteria. The performance of the reactor was represented by power density, and the electrochemical activity was represented by redox capacity. At the same time, micro-electrodes were used to detect the redox potential between biofilms, and the changes in extracellular polymers and microbial community structure under different conditions were also explored. With acetate concentration of 1 g/L and sodium chloride concentration of 0.0125 g/L, the electroactive microorganisms were more sensitive to toxic substances and responded fast. The biofilm also evenly covered on the surface of the carrier, which aided in the diffusion of substances. Although the maximum power density monotonically increased with acetate concentration, high concentration of substrate may mask the inhibitory effect and affect the judgment of inhibitory results. The content of protein and polysaccharide increased monotonically with sodium chloride concentration. However, more polysaccharides would lead to high resistance to electron transfer. Compared to sodium chloride, the microbial content was more affected by acetate. The electroactive microorganisms had strong adaptability to salinity. In practical application, it is conducive to increase the sensitivity of MFCs to reasonably reduce the concentration of acetic acid and sodium chloride. Full article

This study provides a comprehensive characterization of the microbiological, chemical, and sensory profiles of Sicilian Canestrato Fresco (SCF) cheese, a traditional agri-food product (TAP) made from raw cow’s milk using artisanal methods and typically consumed after 20 d of ripening. Plate count analyses confirmed high levels of mesophilic lactic acid bacteria (LAB) exceeding 10⁸ CFU/g. Both rod- and coccus-shaped LAB populations were present at these elevated levels. Pathogens such as Listeria monocytogenes and Salmonella spp. were not detected, although potential contaminants including Enterobacteriaceae, total coliforms, and Escherichia coli were detected at levels of 1.0–3.5 log CFU/g. High-throughput sequencing confirmed LAB as the dominant taxa, comprising the majority of the bacterial community, which accounted for 78.12% to 99.63% of the total relative abundance (RA) across all cheese samples. The fatty acid profile was typical of cow’s milk cheeses, with long-chain fatty acids (C15–C18) representing ~75% of the total, followed by medium- (~17%) and short-chain (<8%) fatty acids. Volatile organic compound analysis showed free fatty acids as the most abundant class, followed by esters, alcohols, ketones, and aldehydes. These findings highlight the role of traditional practices in preserving the sensory and chemical identity of SCF cheese. However, the presence of hygiene indicators suggests a need for improving sanitary measures along the production chain. Future research should explore the impact of targeted microbial management and packaging conditions to enhance both safety and product standardization without compromising artisanal traits. Full article

Soil microbial communities are pivotal in maintaining ecosystem functions, particularly in alpine regions with highly heterogeneous environmental conditions. However, the influence of vegetation type on soil microbial communities in high-elevation areas remains insufficiently understood. This study investigates the dynamics of soil microbial communities across grassland, shrubland, and forest ecosystems on the southern slope of the Qilian Mountains. Soil bacterial and fungal communities were examined using high-throughput 16S rRNA and ITS gene sequencing, and their potential ecological functions were inferred using the FAPROTAX and FUNGuild databases. Analysis of similarity (ANOSIM) based on Bray–Curtis distances revealed significant differences in bacterial and fungal community structures among vegetation types, with forest soils showing greater intra-group variability and more distinct microbial assemblages. Acidobacteriota and Proteobacteria were the dominant bacterial phyla, while Basidiomycota and Ascomycota predominated among fungi. Fungal communities in forest soils were dominated by ectomycorrhizal taxa, closely linked to coniferous forests dominated by Picea crassifolia. Overall, the structure and functional diversity of soil microbial communities were governed by soil physicochemical properties, particularly soil pH, which emerged as a key influencing factor. These findings deepen our understanding of microbial ecological processes in alpine environments and offer valuable insights for effective vegetation management and ecosystem conservation in mountainous regions. Full article

The rapid rise in obesity has evolved into a critical global public health concern. Considering the potential adverse effects of current anti-obesity medications, the development of functional foods sourced from natural materials has emerged as a viable alternative. Blueberries, a category of berry fruits, exhibit potential anti-obesity characteristics. In this research, we assessed the impacts of Blueberry extract rich in anthocyanins (BE) on lipid metabolism and liver health in a high-fat diet (HFD)-induced obese mouse model. The findings indicated that BE notably diminished lipid accumulation in both serum and the liver, and mitigated hepatic steatosis and oxidative stress. Integrated proteomic, metagenomic, and metabolomic analyses further revealed the underlying mechanisms. Consumption of BE intake reconfigured the gut microbiota composition and reduced the microbial capacity for secondary bile acid metabolism, thereby interrupting bile acid recycling and facilitating fecal excretion. This process led to a reduction in systemic cholesterol levels and ultimately alleviated hepatic lipid accumulation, resulting in enhanced liver health. Full article