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1.
Sci Total Environ ; 912: 168820, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38036148

RESUMEN

The energy industry generates large volumes of produced water (PW) as a byproduct of oil and gas extraction. In the central United States, PW disposal occurs through deep well injection, which can increase seismic activity. The treatment of PW for use in agriculture is an alternative to current disposal practices that can also provide supplemental water in regions where limited freshwater sources can affect agricultural production. This paper assesses the potential for developing PW as a water source for agriculture in the Anadarko basin, a major oil and gas field spanning parts of Kansas, Oklahoma, Colorado, and Texas. From 2011 to 2019, assessment of state oil and gas databases indicated that PW generation in the Anadarko Basin averaged 428 million m3/yr. A techno-economic analysis of PW treatment was combined with geographical information on PW availability and composition to assess the costs and energy requirements to recover this PW as a non-conventional water resource for agriculture. The volume of freshwater economically extractable from PW was estimated to be between 58 million m3 per year using reverse osmosis (RO) treatment only and 82 million m3 per year using a combination of RO and mechanical vapor compression to treat higher salinity waters. These volumes could meet 1-2 % and 49-70 % of the irrigation and livestock water demands in the basin, respectively. PW recovery could also modestly contribute to mitigating the decline of the Ogallala aquifer by ~2 %. RO treatment costs and energy requirements, 0.3-1.5 $/m3 and 1.01-2.65 kWh/m3, respectively, are similar to those for deep well injection. Treatment of higher salinity waters increases costs and energy requirements substantially and is likely not economically feasible in most cases. The approach presented here provides a valuable framework for assessing PW as a supplemental water source in regions facing similar challenges.

2.
Appl Soil Ecol ; 1872023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37786531

RESUMEN

Soil microorganisms play critical roles in the degradation of micro-and nano-pollutants, and the corresponding proteins and enzymes play roles in pollutant recognition, transportation, and degradation. Our ability to study these pathways from soil samples is often complicated by the complex processes involved in extracting proteins from soil matrices. This study aimed to develop a new protein soil extraction protocol that yielded active, intracellular enzymes from the perchlorate degradation pathway, particularly perchlorate reductase. An indirect method, which focused on first separating the cells from the soil matrix, followed by cell lysis and enzyme extraction, was evaluated. The optimized indirect method achieved a final extraction efficiency of the active enzyme and total protein of 15.7 % and 3.3 %, respectively. The final step of separating enzymes from residual soil components resulted in the highest activity and protein losses of 67.7 % ± 14.8 % and 91.8 % ± 1.8 %, respectively. Five buffers, each at different concentrations (0.01 M, 0.05 M, and 0.1 M), were tested to enhance enzyme extraction efficiency. The best extractant requires careful consideration between the highest activity and the quality of the recovered enzymes. Coextraction of humic substances could be minimized by using 0.1 M as compared to 0.01 M and 0.05 M of sodium pyrophosphate; however, this resulted in less recovered activity compared to lower extractant concentrations.

3.
Environ Sci Technol ; 57(43): 16317-16326, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37856833

RESUMEN

Recovering phosphate (P) from point sources such as wastewater effluent is a priority in order to alleviate the impacts of eutrophication and implement a circular economy for an increasingly limited resource. Bioadsorbents featuring P-binding proteins and peptides offer exquisite P specificity and sensitivity for achieving ultralow P concentrations, i.e., <100 µg P L-1, a discharge limit that has been implemented in at least one treatment facility in nine U.S. states. To prioritize research objectives for P recovery in wastewater treatment, we compared the financial and environmental sustainability of protein/peptide bioadsorbents to those of LayneRT anion exchange resin. The baseline scenario (reflecting lab-demonstrated performance at a full-scale implementation) had costs that were 3 orders of magnitude higher than those for typical wastewater treatment. However, scenarios exploring bioadsorbent improvements, including increasing the P-binding capacity per unit volume by using smaller P-selective peptides and nanoparticle base materials and implementing reuse, dramatically decreased median impacts to $1.06 m-3 and 0.001 kg CO2 equiv m-3; these values are in line with current wastewater treatment impacts and lower than the median LayneRT impacts of $4.04 m-3 and 0.19 kg CO2 equiv m-3. While the financial viability of capturing low P concentrations is a challenge, incorporating the externalities of environmental impacts may provide a feasible path forward to motivate ultralow P capture.


Asunto(s)
Eliminación de Residuos Líquidos , Aguas Residuales , Fósforo , Desarrollo Sostenible , Dióxido de Carbono , Péptidos
4.
Environ Sci Technol ; 57(35): 12969-12980, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37611169

RESUMEN

Wastewater-based testing (WBT) for SARS-CoV-2 has rapidly expanded over the past three years due to its ability to provide a comprehensive measurement of disease prevalence independent of clinical testing. The development and simultaneous application of WBT measured biomarkers for research activities and for the pursuit of public health goals, both areas with well-established ethical frameworks. Currently, WBT practitioners do not employ a standardized ethical review process, introducing the potential for adverse outcomes for WBT professionals and community members. To address this deficiency, an interdisciplinary workshop developed a framework for a structured ethical review of WBT. The workshop employed a consensus approach to create this framework as a set of 11 questions derived from primarily public health guidance. This study retrospectively applied these questions to SARS-CoV-2 monitoring programs covering the emergent phase of the pandemic (3/2020-2/2022 (n = 53)). Of note, 43% of answers highlight a lack of reported information to assess. Therefore, a systematic framework would at a minimum structure the communication of ethical considerations for applications of WBT. Consistent application of an ethical review will also assist in developing a practice of updating approaches and techniques to reflect the concerns held by both those practicing and those being monitored by WBT supported programs.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Salud Pública , Estudios Retrospectivos , SARS-CoV-2 , Aguas Residuales , Revisión Ética
5.
medRxiv ; 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37398480

RESUMEN

Wastewater-based testing (WBT) for SARS-CoV-2 has rapidly expanded over the past three years due to its ability to provide a comprehensive measurement of disease prevalence independent of clinical testing. The development and simultaneous application of the field blurred the boundary between measuring biomarkers for research activities and for pursuit of public health goals, both areas with well-established ethical frameworks. Currently, WBT practitioners do not employ a standardized ethical review process (or associated data management safeguards), introducing the potential for adverse outcomes for WBT professionals and community members. To address this deficiency, an interdisciplinary group developed a framework for a structured ethical review of WBT. The workshop employed a consensus approach to create this framework as a set of 11-questions derived from primarily public health guidance because of the common exemption of wastewater samples to human subject research considerations. This study retrospectively applied the set of questions to peer- reviewed published reports on SARS-CoV-2 monitoring campaigns covering the emergent phase of the pandemic from March 2020 to February 2022 (n=53). Overall, 43% of the responses to the questions were unable to be assessed because of lack of reported information. It is therefore hypothesized that a systematic framework would at a minimum improve the communication of key ethical considerations for the application of WBT. Consistent application of a standardized ethical review will also assist in developing an engaged practice of critically applying and updating approaches and techniques to reflect the concerns held by both those practicing and being monitored by WBT supported campaigns. Synopsis: Development of a structured ethical review facilitates retrospective analysis of published studies and drafted scenarios in the context of wastewater-based testing.

6.
ChemSusChem ; 15(22): e202200888, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36129761

RESUMEN

Enzymatic processes, particularly those capable of performing redox reactions, have recently been of growing research interest. Substrate specificity, optimal activity at mild temperatures, high selectivity, and yield are among the desirable characteristics of these oxidoreductase catalyzed reactions. Nicotinamide adenine dinucleotide (phosphate) or NAD(P)H-dependent oxidoreductases have been extensively studied for their potential applications like biosynthesis of chiral organic compounds, construction of biosensors, and pollutant degradation. One of the main challenges associated with making these processes commercially viable is the regeneration of the expensive cofactors required by the enzymes. Numerous efforts have pursued enzymatic regeneration of NAD(P)H by coupling a substrate reduction with a complementary enzyme catalyzed oxidation of a co-substrate. While offering excellent selectivity and high total turnover numbers, such processes involve complicated downstream product separation of a primary product from the coproducts and impurities. Alternative methods comprising chemical, electrochemical, and photochemical regeneration have been developed with the goal of enhanced efficiency and operational simplicity compared to enzymatic regeneration. Despite the goal, however, the literature rarely offers a meaningful comparison of the total turnover numbers for various regeneration methodologies. This comprehensive Review systematically discusses various methods of NAD(P)H cofactor regeneration and quantitatively compares performance across the numerous methods. Further, fundamental barriers to enhanced cofactor regeneration in the various methods are identified, and future opportunities are highlighted for improving the efficiency and sustainability of commercially viable oxidoreductase processes for practical implementation.


Asunto(s)
NAD , Niacinamida , Biocatálisis , NAD/química , Oxidación-Reducción , NADP/metabolismo , Oxidorreductasas/metabolismo , Regeneración
7.
Artículo en Inglés | MEDLINE | ID: mdl-36118159

RESUMEN

The COVID-19 pandemic has highlighted the potential role that wastewater-based epidemiology can play in assessing aggregate community health. However, efforts to translate SARS-CoV-2 gene copy numbers obtained from wastewater samples into meaningful community health indicators are nascent. In this study, SARS-CoV-2 nucleocapsid (N) genes (N1 and N2) were quantified weekly using reverse transcriptase droplet digital PCR from two municipal wastewater treatment plants for seven months. Four biomarkers (ammonium, biological oxygen demand (BOD), creatinine, and human mitochondrial gene NADH dehydrogenase subunit 5) were quantified and used to normalize SARS-CoV-2 gene copy numbers. These were correlated to daily new case data and one-, two-, and three-week cumulative case data. Over the course of the study, the strongest correlations were observed with a one-day case data lag. However, early measurements were strongly correlated with a five-day case data lag. This indicates that in the early stages of the pandemic, the wastewater samples may have indicated active COVID-19 cases before clinical indications. Mitochondrial and creatinine normalization methods showed the strongest correlations throughout the study, indicating that human-specific biomarkers were better at normalizing wastewater data than ammonium or BOD. Granger causality tests supported this observation and showed that gene copies in wastewater could be predictive of new cases in a sewershed.

8.
Chemosphere ; 307(Pt 4): 135989, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35988768

RESUMEN

Phthalate esters (PAEs) are hazardous organic compounds that are widely added to plastics to enhance their flexibility, temperature, and acidic tolerance. The increase in global consumption and the corresponding environmental pollution of PAEs has caused broad public concerns. As most PAEs accumulate in soil due to their high hydrophobicity, composting is a robust remediation technology for PAE-contaminated soil (efficiency 25%-100%), where microbial activity plays an important role. This review summarized the roles of the microbial community, biodegradation pathways, and specific enzymes involved in the PAE degradation. Also, other green technologies, including biochar adsorption, bioaugmentation, and phytoremediation, for PAE degradation were also presented, compared, and discussed. Composting combined with these technologies significantly enhanced removal efficiency; yet, the properties and roles of each bacterial strain in the degradation, upscaling, and economic feasibility should be clarified in future research.


Asunto(s)
Compostaje , Ácidos Ftálicos , Contaminantes del Suelo , Biodegradación Ambiental , Dibutil Ftalato , Ésteres , Plásticos , Suelo , Contaminantes del Suelo/análisis , Tecnología
9.
Fuel (Lond) ; 3092022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35722593

RESUMEN

Surface complexation models (SCM), based mainly on the diffuse double layer (DDL) theory, have been used to predict zeta potential at the crude oil-brine-rock (COBR) interface with limited success. However, DDL is inherently limited in accurately predicting zeta potential by the assumptions that all the brine ions interact with the rock surface at the same plane and by the double layer collapse at higher brine ionic strength (>1M). In this work, a TLM-based SCM captured zeta potential trends at the calcite-brine interface with ionic strength up to 3 M. An extended DDL and TLM-based SCMs were used to predict the electrokinetic properties of a composite carbonate rock showing a different mineralogical composition. The extended TLM-based SCM captured the zeta potential prediction trends and magnitude, highlighting the contribution of the inorganic minerals and organic impurities on the composite carbonate surface. In contrast, the extended DDL-based SCM captured the zeta potential trends but failed to capture the magnitude of the measured zeta potential. Interestingly, the TLM-based SCM predicted a positive SP for the rock-brine interface, which could explain the oil-wet nature of composite carbonate rocks due to electrostatic adsorption of negatively charged carboxylic acids. Conversely, the DDL-based SCM predicted a negative SP, leading to an inaccurate interpretation of the electrokinetic properties at the rock-brine interface. Thus, the use of extended TLM-based SCM was required to accurately predict the zeta potential and account for the adsorption of carboxylic acids on the reservoir composite carbonate surface.

10.
Water Res X ; 12: 100112, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34409281

RESUMEN

New water and wastewater treatment technologies are required to meet the demands created by emerging contaminants and resource recovery needs, yet technology development is a slow and uncertain process. Through evolution, nature has developed highly selective and fast-acting proteins that could help address these issues, but research and application have been limited, often due to assumptions about stability and economic feasibility. Here we highlight the potential advantages of cell-free, protein-based water and wastewater treatment processes (biocatalysis and biosorption), evaluate existing information about their economic feasibility, consider when a protein-based treatment process might be advantageous, and highlight key research needs.

11.
Patient Educ Couns ; 104(2): 290-297, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32988686

RESUMEN

BACKGROUND: Patients receiving novel treatments like immune checkpoint inhibitor therapy (ICI or immunotherapy) to treat their cancer require comprehensive information so they know what to expect and to encourage the identification and reporting of possible side-effects. Videos using patient stories can be reassuring and an effective method for conveying health information. OBJECTIVE: The objective of this study was to use a co-design process to develop video resources about immunotherapy to identify a) the key informational and supportive care needs of patients and family carers and b) topics clinicians recommended be addressed during pre-treatment nurse-led education. PATIENT INVOLVEMENT: Experience Based Co-design (EBCD) provided the framework for video development, to facilitate patient and carer involvement in every stage of research design and implementation, and video design and development. METHODS: Data were collected and used in four stages: 1) qualitative interviews, 2) co-design workshop, 3) filming plan and 4) feedback and editing. RESULTS: Thirty-five individuals contributed to the development of a suite of five videos called "Immunotherapy: What to Expect". Videos covered general treatment information, preparation for infusion, potential side-effects, balancing lifestyle with treatment and seeking support. Video run time ranges from 6 to 15 min. DISCUSSION: The EBCD process ensured that videos were developed to meet patient and carer identified needs associated with commencing and managing ICI therapy. The structure of EBCD in facilitating patient and carer involvement throughout the research and video development process ensured transparency throughout the project, and continuity of message, scope and outcomes. PRACTICAL VALUE: EBCD is a useful framework for developing patient-centred health resources. The videos developed are now available for patients and carers via YouTube, and provide education and support tailored to this groups' needs regarding ICI therapy for cancer.


Asunto(s)
Medios de Comunicación , Neoplasias , Cuidadores , Humanos , Inmunoterapia , Neoplasias/terapia , Encuestas y Cuestionarios
12.
Environ Sci Technol ; 51(12): 7178-7186, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28497961

RESUMEN

Removing micropollutants is challenging in part because of their toxicity at low concentrations. A biocatalytic approach could harness the high affinity of enzymes for their substrates to address this challenge. The potential of biocatalysis relative to mature (nonselective ion exchange, selective ion exchange, and whole-cell biological reduction) and emerging (catalysis) perchlorate-removal technologies was evaluated through a quantitative sustainable design framework, and research objectives were prioritized to advance economic and environmental sustainability. In its current undeveloped state, the biocatalytic technology was approximately 1 order of magnitude higher in cost and environmental impact than nonselective ion exchange. Biocatalyst production was highly correlated with cost and impact. Realistic improvement scenarios targeting biocatalyst yield, biocatalyst immobilization for reuse, and elimination of an electron shuttle could reduce total costs to $0.034 m-3 and global warming potential (GWP) to 0.051 kg CO2 eq m-3: roughly 6.5% of cost and 7.3% of GWP of the background from drinking water treatment and competitive with the best performing technology, selective ion exchange. With less stringent perchlorate regulatory limits, ion exchange technologies had increased cost and impact, in contrast to biocatalytic and catalytic technologies. Targeted advances in biocatalysis could provide affordable and sustainable treatment options to protect the public from micropollutants.


Asunto(s)
Agua Potable , Percloratos , Purificación del Agua , Catálisis , Intercambio Iónico
13.
Front Microbiol ; 8: 2423, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29312158

RESUMEN

This work investigated the potential for biocatalytic degradation of micropollutants, focusing on chlorine oxyanions as model contaminants, by mining biology to identify promising biocatalysts. Existing isozymes of chlorite dismutase (Cld) were characterized with respect to parameters relevant to this high volume, low-value product application: kinetic parameters, resistance to catalytic inactivation, and stability. Maximum reaction velocities (Vmax) were typically on the order of 104 µmol min-1 (µmol heme)-1. Substrate affinity (Km) values were on the order of 100 µM, except for the Cld from Candidatus Nitrospira defluvii (NdCld), which showed a significantly lower affinity for chlorite. NdCld also had the highest susceptibility to catalytic inactivation. In contrast, the Cld from Ideonella dechloratans was least susceptible to catalytic inactivation, with a maximum turnover number of approximately 150,000, more than sevenfold higher than other tested isozymes. Under non-reactive conditions, Cld was quite stable, retaining over 50% of activity after 30 days, and most samples retained activity even after 90-100 days. Overall, Cld from I. dechloratans was the most promising candidate for environmental applications, having high affinity and activity, a relatively low propensity for catalytic inactivation, and excellent stability.

14.
Environ Sci Technol ; 47(17): 9934-41, 2013 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-23924304

RESUMEN

Existing methods for perchlorate remediation are hampered by the common co-occurrence of nitrate, which is structurally similar and a preferred electron acceptor. In this work, the potential for perchlorate removal using cell-free bacterial enzymes as biocatalysts was investigated using crude cell lysates and soluble protein fractions of Azospira oryzae PS, as well as soluble protein fractions encapsulated in lipid and polymer vesicles. The crude lysates showed activities between 41 700 to 54 400 U L(-1) (2.49 to 3.06 U mg(-1) total protein). Soluble protein fractions had activities of 15 400 to 29 900 U L(-1) (1.70 to 1.97 U mg(-1)) and still retained an average of 58.2% of their original activity after 23 days of storage at 4 °C under aerobic conditions. Perchlorate was removed by the soluble protein fraction at higher rates than nitrate. Importantly, perchlorate reduction occurred even in the presence of 500-fold excess nitrate. The soluble protein fraction retained its function after encapsulation in lipid or polymer vesicles, with activities of 13.8 to 70.7 U L(-1), in agreement with theoretical calculations accounting for the volume limitation of the vesicles. Further, encapsulation mitigated enzyme inactivation by proteinase K. Enzyme-based technologies could prove effective at perchlorate removal from water cocontaminated with nitrate or sulfate.


Asunto(s)
Proteínas Bacterianas/metabolismo , Oxidorreductasas/metabolismo , Percloratos/metabolismo , Rhodocyclaceae/enzimología , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Cromatografía por Intercambio Iónico , Colorimetría , Agua Potable/análisis
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