Search Results (2,246)

Wastewater treatment systems are under increasing pressure to improve nitrogen removal while reducing carbon emissions, yet the deployment of anaerobic ammonium oxidation (anammox) remains constrained by uncertainty about technical readiness, operational robustness, nitrous oxide (N₂O) emissions, life-cycle carbon performance, monitoring capacity, and transferability across wastewater contexts. This study uses dynamic topic modelling and trend assessment of 998 publications from 2001 to 2025 to synthesize deployment-relevant evidence for anammox-based wastewater treatment. The results indicate that the field has shifted from reactor start-up and process-parameter optimization toward microbial regulation, mainstream process integration, coupled nitrogen-removal strategies, and intelligent control. Building on these topic-evolution patterns and reported engineering evidence, this study provides an evidence-based qualitative appraisal of deployment-readiness signals and evidence gaps, distinguishing comparatively mature side-stream applications from mainstream systems that still require monitored demonstrations, transparent N₂O accounting, life-cycle assessment, and locally validated operating data. The study argues that anammox should be evaluated as a technology with potential but conditional carbon-saving benefits: its potential carbon-saving benefits depend on operational evidence specific to each application stage, carbon-accounting credibility, and implementation capacity, rather than assuming that research activity alone justifies broad deployment. Full article

Orange waste (OW) is an example of biomass that has a potential for nutrients and energy recovery. However, its use in biological processes, e.g., anaerobic digestion (AD), still poses a significant technological challenge due to the presence of hardly biodegradable lignin and compounds toxic to the microorganisms. To release its energetic potential, the use of an adequate pre-treatment method might be a solution. This research evaluated the efficacy of various pre-treatment strategies, i.e., acoustics (AC) and hydrodynamic cavitation (HC), microwave radiation (MR), and the impact of solidified carbon dioxide (SCD) in improving the properties of OW, including organic compound content, fiber components, morphological structure, and generation of toxic intermediates. The obtained results showed that HC might be considered as the most efficient pre-treatment strategy prior to its further AD decomposition. For this strategy, an over 2-fold increase in biodegradability index, expressed as the DOC/TOC (dissolved to total organic carbon) ratio, was found. In turn, the other analyzed parameters, i.e., removal of organic compounds and delignification degree, were established at the favorable level of 63 and 56%, respectively. This effect was achieved with the lowest energy demand of 0.35 MJ/kgVS. However, HC favored the generation of AD inhibitors. However, to fully assess the impact of selected methods on AD performance, further experiments should be conducted. Full article

Background/Objectives: Oseltamivir is a widely used antiviral agent indicated for the treatment of influenza and plays a central role in pandemic preparedness strategies. Although an extemporaneously prepared 15 mg/mL oral solution is recognized in formularies, preparing large volumes during a pandemic requires extended storage options. However, no stability studies are currently available for an oseltamivir 15 mg/mL oral solution stored under freezing and subsequent refrigerated conditions for the duration of a standard treatment. The aim of this study was to evaluate the physicochemical and microbiological stability of a 15 mg/mL oseltamivir oral solution prepared from the active pharmaceutical ingredient (API) and packaged in amber glass containers. Methods: The oral solution was formulated using oseltamivir phosphate API, sodium benzoate as a preservative, and purified water and then packaged in 125 mL Type II amber glass bottles, allowing for thermal expansion. The samples were stored at −20 ± 2 °C for up to 75 days, followed by refrigerated storage (5 ± 3 °C) after thawing for up to 10 days. Chemical stability was assessed using a validated HPLC method in accordance with ICH guidelines and was defined as 90–110% recovery of the initial concentration. Physical stability (color, pH, particulate matter, crystallization, and homogeneity) and microbiological stability were also evaluated. Results: The HPLC method demonstrated excellent linearity, precision, and accuracy. Oseltamivir concentrations remained within the predefined acceptance limits throughout the 75-day study period under freezing conditions, with no significant changes in pH, color, or particulate formation. After thawing, the drug concentration continued to remain fully stable and within the required limits for up to 10 days under refrigerated conditions. Despite the prolonged storage and phase changes, no significant changes in physical parameters were observed, and microbiological testing confirmed the absence of aerobic, anaerobic, and fungal microorganisms on the final day of the study. Conclusions: Oseltamivir 15 mg/mL oral solution in amber glass bottles is physicochemically and microbiologically stable for up to 85 days (75 days under frozen conditions plus 10 days under refrigeration after thawing). Full article

Hydrothermal pretreatment is widely proposed to improve the anaerobic digestibility of lignocellulosic biomass, yet whether it repays its own energy input is rarely quantified. We compare microwave- and conventional (conductive) acid-assisted thermohydrolysis of willow (Salix viminalis) and maize silage at 110–130 °C, coupling biochemical methane potential (BMP, n = 3) with an incremental energy balance against an untreated control. Substrate, heating mode and temperature were all significant (p < 0.001), with heating mode dominating. Maize silage responded monotonically, reaching 306.0 ± 4.0 NmL CH4 g⁻¹ VS at 130 °C under microwave heating (+31.4%), whereas willow behaved erratically: its best variant reached 310.6 ± 2.5 NmL CH4 g⁻¹ VS (+28.9%), yet two conductively heated variants fell below the control. Furanic by-products stayed at trace levels, well below inhibitory thresholds, excluding toxicity. Critically, no variant recovered its own energy input: every treatment was net-negative, the least unfavourable being microwave heating at 110 °C (−3.57 and −3.48 kJ g⁻¹ DM). Heating mode changed the penalty three- to five-fold, microwave being superior in all six paired comparisons. Under the mild conditions tested, acid-assisted thermohydrolysis was not self-financing in energy terms; where applied for other reasons, microwave heating is the less unfavourable of the two modes tested, although neither returns a net energy gain. Full article

Mannan oligosaccharides (MOS) are functional prebiotics that selectively promote the proliferation of beneficial bacteria in the chicken intestinal tract. This study evaluated the effects of in ovo MOS injection on early growth, intestinal morphology, and cecal microbiota of broilers at 7, 14, and 21 days post-hatch (dph). In total, 700 Cobb 500 fertilized eggs received either no injection or 200 μL of PBS diluent, low (0.5 mg/egg), medium (5 mg/egg), or high (10 mg/egg) doses of MOS in the amnion. At hatch, approximately 280 male hatchlings from injection groups were distributed into 28 cages and raised until 21 dph. Our results indicated that MOS injection linearly increased feed intake and body weight during 0–7 dph and improved duodenal villus height and width, with no persistent improvements observed at older age. Moreover, microbiota shifts triggered by MOS were only observed at 7 dph. The MOS injection at 0.5 mg/egg reduced genus-level Sobs, and PCoA coupled with ADONIS analysis confirmed microbial separation across treatments (p = 0.017). MOS selectively enriched obligate anaerobic taxa, including Lachnospiraceae, Pseudoflavonifractor, and Collidextribactor (0.5 mg/egg), and Ruminococcus gauvreauii (5 mg/egg). Conversely, control-enriched genera (Enterococcus and Litchfieldia) were negatively correlated with body weight gain. In conclusion, in ovo administration of MOS at 0.5 mg/chick transiently improved the abundance of beneficial anaerobes, and injecting 10 mg MOS could improve villus morphology and growth performance in chicks in the first week, suggesting a potential role for MOS in shaping early microbial establishment in broilers. Full article

Background/Objectives: Reductive soil disinfestation (RSD) is increasingly viewed as a viable alternative to chemical fumigation, yet the role of organic amendment quality in regulating greenhouse gas (GHG) fluxes, soil organic carbon (SOC) dynamics, and net climate forcing remains poorly understood. Methodology: In a 30-day anaerobic incubation experiment, we set up three treatments—a flooded control (CK), soil amended with wheat straw (WS, C/N = 55.5), and soil amended with kiwifruit branches (KB, C/N = 110.8)—each replicated three times under identical conditions. Results: Both WS and KB additions strongly stimulated CO₂ and CH₄ production, while suppressing N₂O emissions by over 85% relative to CK. The WS treatment exhibited a substantially higher global warming potential (GWP, 823.52 t ha⁻¹) than KB (636.23 t ha⁻¹), with CH₄ accounting for more than 99% of total GWP. Although WS surpassed KB in short-term carbon sequestration efficiency (25.79% vs. 20.11%) and showed greater hydrolytic enzyme activities (βG, CBH, and XYL), the two organic amendments diverged clearly in carbon fraction distribution: C_mic was 17.9% higher under WS, whereas C_min was 16.2% higher under KB. When factoring in the CO₂ equivalent benefit derived from carbon sequestration, the net GWP (NGWP) indicated that both RSD treatments remained net GHG sources. Notably, KB yielded a markedly lower NGWP (611.60 t CO₂-eq ha⁻¹) than WS (798.19 t CO₂-eq ha⁻¹), highlighting a fundamental trade-off: WS favored rapid SOC accumulation at the expense of elevated methane emissions, whereas KB achieved a smaller climatic footprint despite more moderate carbon retention. Conclusions: These findings underscore that selecting organic amendments for field RSD requires balancing the competing goals of carbon sequestration and GHG mitigation. Full article

Background/Objectives: The application of organic soil amendments constitutes an important source of antibiotic residues in agricultural soils. However, studies have mainly focused on a few parent tetracyclines, whereas information on their transformation products (TPs) in organic amendments remains scarce. Therefore, this study assessed the occurrence and environmental risk of six tetracyclines and seven TPs in organic amendments. Methods: Processed livestock manures applied in the European Union (horse, poultry, and bovine manure), as well as fresh and treated sewage sludge, were analyzed using matrix solid-phase dispersion (MSPD) combined with online SPE-LC-MS/MS. Environmental risk was assessed using risk quotients (RQs) based on predicted environmental concentrations in soil (PEC_soil) calculated from the maximum measured concentrations and predicted no-effect concentrations in soil (PNEC_soil) obtained either directly from terrestrial ecotoxicity data or derived from aquatic ecotoxicity data using the equilibrium partitioning method and soil-water distribution coefficients. Results: Tetracyclines and their TPs were widely detected in both sample types, although concentrations varied according to matrix type and treatment. Overall, sludge showed higher detection frequencies and concentrations than manure. Doxycycline and tetracycline were the predominant parent compounds, reaching concentrations up to 2838 ng g⁻¹ dry weight (dw) in manure and 2892 ng g⁻¹ dw in sludge. Epimerized TPs were frequently detected and sometimes exceeded the concentrations of their parent compounds, especially epitetracycline and epioxytetracycline. Among the sludge types and treatment conditions investigated, anaerobically digested sludge showed the highest tetracycline concentrations, whereas the composted sludge sample presented the lowest concentrations. Individual RQs indicated insignificant to low ecotoxicological risk, whereas cumulative RQ (ΣRQ) values, used as conservative estimates of co-exposure to all evaluated tetracyclines and their TPs, fell within the medium-risk category for bovine manure and anaerobically digested sludge, with the composted sludge sample showing the lowest ΣRQ. Conclusions: These findings highlight the importance of including TPs in environmental monitoring and the differences in tetracycline occurrence and environmental risk to soil among the processed manure types and sludge treatment conditions investigated. Full article

Posidonia oceanica (P. oceanica) is a key marine seagrass that provides essential ecosystem services but managing its stranded biomass (banquettes) poses a challenge to local authorities due to high disposal costs. This review examines the ecological and bioenergetic potential of P. Oceanica, focusing on the Calabria region. Through the analysis of regional monitoring data (ARPACAL) and a comprehensive review of the literature on anaerobic digestion (AD) processes, the study analyzes the transition from waste to resource. The results highlight a worrying regression of Calabrian meadows due to siltation and high burial-induced mortality. Chemically, the biomass is characterized by high recalcitrance (lignin > 34%) and an unbalanced C/N ratio (~153), which limits the efficiency of standard AD. However, the review demonstrates that acidic thermochemical pretreatment (132 °C with 0.4% HCl) can increase methane yields by up to 575%, while co-digestion with nitrogenous substrates further stabilizes the process. The study concludes that, although technical challenges such as reactor corrosion and sediment loss remain, the transformation of P. oceanica into biomethane represents a technologically potential route toward a circular Blue Economy, provided that operational and economic trade-offs are carefully balanced. Adopting the “Ecological Beach” model could enable sustainable coastal protection while unlocking prospective renewable energy potential. Full article

Winter ice-cover periods pose substantial risks to Apostichopus japonicus aquaculture in northern China. We combined field monitoring of three representative aquaculture ponds between 2014 and 2017 with controlled single-factor laboratory exposures to low temperature, hypoxia, and hyposalinity in adult and juvenile sea cucumbers. Field observations revealed pronounced temporal, vertical, spatial, and interannual variability in water temperature, salinity, and dissolved oxygen (DO) during freezing and ice-melting periods. All three stressors caused clear deterioration in physiological condition, with juveniles generally exhibiting greater short-term sensitivity than adults under low-temperature and hypoxic exposure, whereas severe hyposalinity caused pronounced deterioration in both life stages. Lactate, malondialdehyde (MDA), and glutathione (GSH) showed distinct treatment- and time-dependent responses, consistent with stress-associated changes in anaerobic metabolism, lipid peroxidation, and glutathione-associated antioxidant status. Integration of field observations with laboratory responses indicated that water temperatures approaching 0 °C and salinities approaching approximately 20‰ represent environmentally relevant conditions associated with elevated overwintering risk. DO concentrations approaching approximately 3 mg/L may warrant intensified monitoring and management intervention, whereas 2 mg/L represents a more severe experimental hypoxia condition. The more extreme treatments of −2 °C and 15‰ should similarly be regarded as severe experimental scenarios rather than commonly occurring field conditions. These environmental values should therefore be interpreted as preliminary management-oriented risk references rather than definitive physiological thresholds. Overall, the study provides an empirical field-to-laboratory basis for biologically informed winter environmental monitoring and risk-based overwintering management of A. japonicus aquaculture. Full article

Nickel (Ni) and copper (Cu) are essential soil micronutrients that are beneficial for plant growth and development when applied at the right levels to deficient soils. However, they can also be of concern if excessive application leads to accumulation in soil, causing soil fertility problems that can compromise food production as well as result in human exposure to these metals if they enter the food chain. The application of Ni and Cu salts can strongly influence the nitrogen (N) cycle as they can stimulate soil microbiological activity that leads to N losses to the atmosphere. A laboratory incubation was conducted to study the effect of these metal salts on gaseous N emissions. Copper sulphate (CuSO₄) and nickel sulphate (NiSO₄) were applied at rates below soil toxicity (3.0 kg Ni/ha and 7.5 kg Cu/ha), together with ¹⁵N-labelled-urea (rate 100 kg N/ha) and under two soil water-filled pore space (WFPS) conditions: continuous anaerobic (75% WFPS) versus aerobic (50% WFPS) followed by an anaerobic (75% WFPS) cycle. Results showed no significant effect of the Ni application on nitric oxide (NO) emissions at the low rates applied. However, there was an indication of a meaningful (p = 0.051) production of this gas under aerobic soil conditions. No N₂ emissions were observed from any treatment (only expected to occur under anaerobic conditions) during the 43 days of the incubation, which could suggest that, as for Ni, the selected Cu application rate may not clearly stimulate the complete denitrification process to produce N₂. It is possible that the expected increase in N₂ emissions or larger NO emissions were counteracted by the low amount of soil-extractable Cu and Ni available after application because of binding processes with the clay fraction (48% clay) and the acid nature of the Cambisol used in the incubation. Further research into the effect of metal applications to contrasting soil types, with varied application rates and repeated application events, and under differing soil moisture conditions on N emissions is required. Furthermore, experiments should also be conducted at finer scales to elucidate the specific effect of these metal application rates on the biochemical processes responsible for the N gases produced. Full article

Considering the limited information available on the use of elephant grass juice (EGJ) as a liquid co-substrate, this study aimed to evaluate its feasibility and biogas production potential for anaerobic co-digestion with dairy cattle wastewater (DCW), focusing on substrate ratios and reactor operating conditions. Initially, batch tests were conducted at different temperatures to evaluate the effects of varying substrate mixture ratios (EGJ/DCW). In the reactor with 20% EGJ/80% DCW at 39 °C, a biogas volume of 414.35 mL was generated, which was considerably higher than that in the test at 25 °C, where 258.7 mL was generated over the 30-day experimental period. Greater efficiency in organic matter removal and other analyzed parameters was also observed under these conditions. The best configuration was selected for the semi-continuous tests. To this end, an Upflow Anaerobic Sludge Blanket (UASB) reactor was operated with hydraulic retention times of 10, 6, 2, and 1 d and volumetric organic loading rates of 2.06, 3.39, 10.40, and 20.70 kg VS m⁻³ d⁻¹, respectively. Volatile solids were removed by 29–58%, with biogas yields ranging from 0.78 to 2.28 m³ m⁻³ d⁻¹ and a maximum CH₄ concentration of 72% (v/v). The co-digestion of the analyzed agricultural waste substrates proved to be a promising approach for bioenergy recovery. These results provide useful guidelines for optimizing co-digestion systems, improving reactor performance, and waste treatment processes. Full article

Melon (Cucumis melo L.) is a globally significant horticultural crop whose fruit quality and postharvest shelf life are profoundly influenced by oxidative stress. Abscisic acid (ABA)-responsive element binding factors (ABFs), which represent the Group A subfamily of the basic leucine zipper (bZIP) transcription factor family, serve as pivotal components in the ABA signaling pathway. These factors play essential roles in regulating plant responses to abiotic stress as well as fruit development and maturation processes. In this study, a total of nine CmABF gene family members (CmABF1–CmABF9) were successfully identified within the melon genome using genome-wide identification techniques. Bioinformatic analysis indicated that all CmABF proteins contain a conserved bZIP domain. Physicochemical property analysis revealed that most of these proteins are unstable hydrophilic proteins and all are localized to the cell nucleus. Phylogenetic analysis categorized the CmABF family into three distinct evolutionary branches (Groups A, B, and C), exhibiting high conservation with homologous genes in Arabidopsis thaliana, Solanum tuberosum, and other species. Promoter analysis demonstrated that CmABF genes are rich in hormone-responsive elements (such as abscisic acid-responsive element (ABRE) and gibberellin-responsive element (GARE)) and stress-responsive elements (such as MYB binding sites (MBS) and anaerobic-response element (ARE)). To investigate their responses to oxidative stress and ABA signaling, we analyzed the expression patterns of these genes in melon fruit at 0, 7, 14, 21, 28, and 35 days of postharvest storage under ozone (O₃, an oxidative stressor), exogenous abscisic acid (ABA), and the ABA synthesis inhibitor nordihydroguaiaretic acid (NDGA) using RNA-seq and qRT-PCR. The results showed that ozone treatment significantly induced the up-regulation of CmABF9 while inhibiting the early expression of CmABF2 and CmABF4. ABA treatment generally promoted the transcription of family members during the late stages of storage (35 d). NDGA treatment suppressed the expression of CmABF2 and CmABF4 during the early storage stage (7 d), while markedly increasing their expression levels at later storage stages (28 d and 35 d), suggesting a compensatory feedback response under endogenous ABA deficiency. Furthermore, protein–protein interaction predictions indicated potential close interactions between CmABF proteins and SnRK2 protein kinases. This study provides a theoretical basis for elucidating the molecular mechanisms of the CmABF family in regulating postharvest oxidative stress in melon and provides candidate gene resources for molecular breeding aimed at enhancing resistance and extending the shelf life of melon fruit. Full article

This review provides a comprehensive analysis of waste-to-hydrogen (WtH) pathways for the conversion of various types of WtH, focusing on hydrogen generation, energy efficiency, environmental implications, and economic viability. The result shows that feedstock characteristics influence each pathway’s feasibility and performance. Thermochemical treatment, particularly gasification, demonstrates high hydrogen yield and the processing versatility of heterogeneous wastes. Hydrogen concentrations of 10–45 vol% can be obtained by dry gasification, while 35–55 vol% H₂ and 70–90% carbon conversion can be obtained by plasma-assisted gasification. Hydrothermal gasification converts 45–70% of the energy in the feedstock, suitable for wet feedstocks. Pyrolysis produces H₂-rich gas along with bio-oil and char, while plasma-assisted pyrolysis could enhance H₂ production by up to threefold compared with conventional catalytic systems. Biological pathways are more suitable for wet and biodegradable wastes. Dark fermentation provides lower H₂ recovery than thermochemical routes, whereas sequential dark and photo-fermentation improves substrate utilization, achieving hydrogen yields of 4.44–4.96 mol H₂/mol glucose and hydrogen production efficiencies of 45.31–82.67%. Among the evaluated feedstocks, plastic waste achieved a hydrogen production rate of 189.6 kg H₂/h, but also generated up to 4.3 kg CO₂-eq/kg H₂. Mixed plastic waste achieved 0.29 kg H₂/kg waste at a levelized cost of hydrogen (LCOH) of 3.41 USD/kg H₂. Integrated systems demonstrated performance improvements, including 71.3% energy efficiency for anaerobic digestion and gasification with heat recovery, 61.6% for gasification coupled with electrochemical CO₂ reduction, and more than 99% CO₂ capture in the latter configuration. The LCOH from investigated pathways vary from 0.3 to 13.37 USD/kg H₂ for different feedstock, conversion technology, system configuration, and carbon management requirements. Overall, gasification appears promising for heterogeneous and energy-dense wastes, as well as biological routes for wet biodegradable fractions, while integrated configurations offer a promising strategy for balancing hydrogen recovery, energy efficiency, economic performance, and environmental impacts. Full article

Two-stage anaerobic digestion (TSAD) is an alternative to single-stage anaerobic digestion, separating hydrolytic–acidogenic and methanogenic phases to improve stability, organic matter degradation, and methane production. This review examines TSAD for co-digestion of sewage sludge (SS) and the organic fraction of municipal solid waste (OFMSW), emphasizing performance, scale-up challenges, digestate intensification, and nutrient recovery. TSAD can increase methane production by 25–50% compared with single-stage systems, while volatile solids removal can reach 87–93% depending on substrate type, temperature regime, hydraulic retention time, and organic loading rate. However, improvement remains variable and depends on substrate biodegradability, reactor configuration, and process control. Beyond methane recovery, the review highlights valorizing digestate as a secondary resource. Digestate post-treatment technologies, including thermal hydrolysis and steam explosion, report methane improvements from 26% to more than 300%, although energy demand and economic feasibility remain constraints. Nitrogen recovery technologies, including ammonia stripping and membrane contactors, can achieve efficiencies above 80–95% under optimized conditions, while phosphorus may be recovered through struvite precipitation, calcium phosphate recovery, or biochar-based pathways. Future TSAD development should integrate biological conversion, digestate recirculation, nutrient recovery, techno-economic assessment, and life-cycle evaluation to support circular, resource-efficient organic waste treatment systems. Full article

Clostridioides difficile infection (CDI) remains a major cause of antibiotic-associated diarrhea, with recurrence largely driven by disruption of the gut microbiota and impaired colonization resistance. Bile acids have emerged as key mediators in this process, as primary conjugated bile acids promote C. difficile spore germination, whereas microbiota-derived secondary bile acids can inhibit germination, vegetative growth, and toxin activity. Diet further modulates CDI susceptibility by shaping microbial composition, short-chain fatty acid production, bile acid transformation, epithelial barrier integrity, and intestinal inflammation. Western-style diets, and low fiber intake, may favor dysbiosis and a bile acid profile permissive to CDI, while fiber-rich and Mediterranean-type dietary patterns may support beneficial anaerobes, microbial metabolites, and mucosal resilience. This narrative review summarizes current evidence on the bile acid–diet–microbiome axis in CDI pathogenesis, recurrence, and therapy. It also discusses standard treatment limitations, microbiome-based therapeutics, dietary interventions, and emerging bile acid-targeted strategies. Understanding this axis may support future precision approaches aimed not only at suppressing C. difficile, but also at restoring microbiota function and durable colonization resistance. Full article