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Due to industrialization and urbanization, the use of detergents inadvertently led to contamination of aquatic environments, thus posing potential threat to aquatic organisms and human health. One of the main components of detergents is linear alkylbenzene sulfonate (LAS), which can cause toxic effects on living organisms, particularly aquatic life in the environment. In this study, floating treatment wetlands (FTWs) mesocosms were developed and augmented with LAS-degrading bacteria. The plant species, Brachiaria mutica (Para grass), was vegetated to establish FTWs and bacterial consortium (1:1:1:1) of Pseudomonas aeruginosa strain PJRS20, Bacillus sp. BRRH60, Acinetobacter sp. strain CYRH21, and Burkholderia phytofirmans Ps.JN was augmented (free or immobilized) in these mesocosms. Results revealed that the FTWs removed LAS from the contaminated water and their augmentation with bacteria slightly increased LAS removal during course of the experiment. Maximum reduction in LAS concentration (94%), chemical oxygen demand (91%), biochemical oxygen demand (93%), and total organic carbon (91%) was observed in the contaminated water having FTWs augmented with bacterial consortium immobilized on polystyrene sheet. This study highlights that the FTWs supported with immobilized bacteria on polystyrene sheets can provide an eco-friendly and sustainable solution for the remediation of LAS-bearing water, especially for developing countries like Pakistan.
This pilot-scale study provided insights to resolve the detergent-contaminated wastewater issue, using floating treatment wetlands (FTWs) augmented with bacteria. The FTWs augmented with bacteria immobilized on a polystyrene sheet and vegetated with Brachiaria mutica led to high degradation of LAS, a toxic compound of detergent, from the contaminated water.
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Detergentes , Poluentes Químicos da Água , Humanos , Áreas Alagadas , Poliestirenos , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Bactérias , ÁguaRESUMO
Extra cellular ß-galactosidase enzyme was purified and characterized from Aspergillus fumigatus PCSIR- 2013. Estimated molecular mass of the enzyme was approximately 95 kDa. by native polyacrylamide gel electrophoresis. Initially, different fermentation parameters were optimized for maximum production of ß-galactosidase. The kinetic study of the partially purified enzyme exhibited that it remained active in broad range of temperature from 25°C to 70°C with an optimum of 60°C. The Km and Vmax were calculated as 9.95mmol/l and 51.78 U/ml/min, respectively. The optimum pH was 5.0, when reaction mixture was incubated for 30 min. The enzyme was very stable in the presence of different metal ions, although Na+ (16%) stimulates the activity at 10mM concentration. In contrast, Ba+2 and Hg+2 have negative effect on enzyme activity and activity decreased to 54% and 19%, respectively. Thermo stability study was revealed that the enzyme retained 72% of its activity at 50°C. Whereas, when enzyme was incubated at 60°C for 120 min, its residual activity was decreased to 42.0%. However, the enzyme was completely inactivated at 80°C after 120 min of pre-incubation. Among different surfactant which incorporated with enzyme, Tween 20 and Triton X-100 both have stimulatory effect and activity increased to 29% and 17%, respectively.
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Aspergillus fumigatus/enzimologia , Proteínas Fúngicas/isolamento & purificação , beta-Galactosidase/isolamento & purificação , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , beta-Galactosidase/metabolismoRESUMO
Soil contamination due to petroleum hydrocarbons is a ubiquitous environmental problem for which efficient remediation alternatives are required. Application of hydrocarbons degrading bacteria with enhanced degradation potential is such an alternative. The aim of present investigation was to induce mutagenicity in Pseudomonas putida through gamma-ray irradiation for the enhanced degradation of crude oil. A total of mutant 10 bacterial strains (300A-J) were screened for their degradation abilities in vitro; among which the performance of 300-B was outstanding. Subsequently, spiked soil (30 g/kg crude oil) was augmented with the wild-type parent strain and mutant 300-B strain in individual experiments. Bacterial inoculation in both experiments enhanced hydrocarbons degradation; however, degradation was 46.3% higher when 300-B mutant strain was employed. This improved oil degradation was found to have a strong positive correlation with the gene abundance and expression of the mutant strain, suggesting its successful survival and catabolic potential in situ. Concomitantly, a better nutrients assimilation and water utilization was observed in the experiment containing 300-B mutant. Yet preliminary, these findings highlight the importance of gamma ray irradiation towards improved degradation potential of previously isolated hydrocarbons degrading bacteria.
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Raios gama , Hidrocarbonetos/metabolismo , Mutagênese , Pseudomonas putida/metabolismo , Pseudomonas putida/efeitos da radiação , Poluentes do Solo/metabolismo , Biotransformação , Petróleo/metabolismo , Pseudomonas putida/isolamento & purificaçãoRESUMO
Constructed wetlands (CWs) have emerged as cost-effective and sustainable treatment systems for the remediation of industrial wastewaters; nevertheless, their potential has mostly been evaluated in laboratory-scale studies. Likewise, endophytic bacteria can enhance plant growth and reduce phytotoxicity under polluted conditions, but their application with pilot-scale CWs has rarely been evaluated. The present study aims to evaluate on-site performance of endophyte-assisted pilot-scale horizontal flow constructed wetlands (HFCWs) for the remediation of effluent from a textile industry. The HFCWs were established by planting Leptochloa fusca in the presence of three endophytic bacterial strains with dye degrading, and plant growth promoting capabilities. We found that the system was able to remove a significant proportion of both organic and inorganic pollutants. Maximum reduction of pollutants was observed in endophyte-augmented HFCWs, where the COD and BOD reduced from 493 to 70â¯mgâ¯l-1 and 190 to 42â¯mgâ¯l-1, respectively, within 48â¯h. Additionally, survival of endophytic bacteria in different components of the HFCWs was also recorded. Treated wastewater was found to be non-toxic and the inoculated bacteria showed persistence in the wastewater as well as rhizo- and endosphere of L. fusca. Accordingly, a positive impact on plant growth was observed in the presence of bacterial augmentation. The system performance was comparable to the vertical flow constructed wetlands (VFCWs) as high nutrients reduction was seen in the presence of this partnership. This pilot-scale study is a step forward toward the field-scale application of phytoremediation coupled with bacterial endophytes as a cost-effective means of on-site wastewater remediation. To the best of our knowledge, this is among the first pilot-scale studies on use of HFCWs for improvement in quality of textile industry effluent as most previous studies are limited either in the context of engineering or lack effective interplay of plant and bacteria.
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Biodegradação Ambiental , Endófitos , Eliminação de Resíduos Líquidos , Áreas Alagadas , Têxteis , Águas Residuárias , Poluentes Químicos da ÁguaRESUMO
For effective remediation of contaminants, plant-endophyte partnership is a promising field to be explored. Generally endophytic bacteria assist their host plant by withstanding the stress induced by the contaminants. The objective of this study was to explore the suitability of plant-bacterial partnership for chlorpyrifos (CP) remediation using ryegrass and a CP degrading endophyte, Mesorhizobium sp. HN3 which belongs to plant growth promoting rhizobia. The inoculated yfp-tagged Mesorhizobium sp. HN3 efficiently colonized in the rhizosphere, enhanced plant growth and degradation of CP and its metabolite 3,5,6 trichloro-2-pyridinol (TCP). Significantly lower CP residues were observed in the roots and shoots of plants vegetated in inoculated soil which might be attributed to the efficient root colonization of HN3yfp. These results suggest the involvement of Mesorhizobium sp. HN3yfp in CP degradation inside the roots and rhizosphere of plants and further emphasize on the effectiveness of endophytic bacteria in stimulating the remediation of pesticide contaminants. This is the first report which demonstrates the efficacy of bacterial endophyte for degradation of CP residues taken up by the plant and enhanced remediation of chlorpyrifos contaminated soil.
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Clorpirifos/metabolismo , Endófitos/metabolismo , Lolium/metabolismo , Mesorhizobium/metabolismo , Rizosfera , Microbiologia do Solo , Poluentes do Solo/metabolismo , Biodegradação AmbientalRESUMO
BACKGROUND: Veterans Health Administration (VHA) primary care providers (PCPs) often see few women, making it challenging to maintain proficiency in women's health (WH). Therefore, VHA in 2010 established Designated WH Providers, who would maintain proficiency in comprehensive WH care and be preferentially assigned women patients. OBJECTIVE: To evaluate early implementation of this national policy. METHODS: At each VHA health care system (N=140), the Women Veterans Program Manager completed a Fiscal Year 2012 workforce capacity assessment (response rate, 100%), representing the first time the national Designated WH Provider workforce had been identified. Assessment data were linked to administrative data. RESULTS: Of all VHA PCPs, 23% were Designated WH Providers; 100% of health care systems and 83% of community clinics had at least 1 Designated WH Provider. On average, women veterans comprised 19% (SD=27%) of the patients Designated WH Providers saw in primary care, versus 5% (SD=7%) for Other PCPs (P<0.001). For women veterans using primary care (N=313,033), new patients were less likely to see a Designated WH Provider than established women veteran patients (52% vs. 64%; P<0.001). CONCLUSIONS: VHA has achieved its goal of a Designated WH Provider in every health care system, and is approaching its goal of a Designated WH Provider at every hospital/community clinic. Designated WH Providers see more women than do Other PCPs. However, as the volume of women patients remains low for many providers, attention to alternative approaches to maintaining proficiency may prove necessary, and barriers to assigning new women patients to Designated WH Providers merit attention.
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Assistência Integral à Saúde/organização & administração , Política de Saúde , Hospitais de Veteranos/organização & administração , Atenção Primária à Saúde/organização & administração , Saúde dos Veteranos , Saúde da Mulher , Adolescente , Adulto , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Pessoa de Meia-Idade , Estados Unidos , United States Department of Veterans AffairsRESUMO
The bacterial strains capable of producing dextransucrase enzyme were isolated from different fruits and vegetables sources. In primary screening, five strains were selected on the basis dextransucrase production and among them L. mesenteroides KIBGE- IB26 isolated from bottle gourd (Lagenaria Vulgaris) was selected for further studies. For the enhancement of enzyme production, different physicochemical parameters were optimized. Maximum production of dextransucrase was achieved after 06 hrs using sucrose (20.0 g/l) as a substrate at 25°C. Maximum dextransucrase production was achieved when medium pH was kept 7.5 before sterilization. In addition, medium was also supplemented with CaCl2 and K2HPO4 and maximum enzyme production was achieved at 0.0025 g/dl calcium chloride and 2.0 g/dl K2HPO4with enzyme activity of 87 DSU/ml/hr. Production of dextransucrase in shorter period of time makes this strain an attractive candidate for commercial production of dextransucrase.
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Proteínas de Bactérias/biossíntese , Glucosiltransferases/biossíntese , Leuconostoc/enzimologia , Cloreto de Cálcio/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Fosfatos/metabolismo , Compostos de Potássio/metabolismo , Sacarose/metabolismo , Temperatura , Fatores de TempoRESUMO
BACKGROUND: Cassava starch is considered as a potential source for the commercial production of bioethanol because of its availability and low market price. It can be used as a basic source to support large-scale biological production of bioethanol using microbial amylases. With the progression and advancement in enzymology, starch liquefying and saccharifying enzymes are preferred for the conversion of complex starch polymer into various valuable metabolites. These hydrolytic enzymes can selectively cleave the internal linkages of starch molecule to produce free glucose which can be utilized to produce bioethanol by microbial fermentation. RESULTS: In the present study, several filamentous fungi were screened for production of amylases and among them Aspergillus fumigatus KIBGE-IB33 was selected based on maximum enzyme yield. Maximum α-amylase, amyloglucosidase and glucose formation was achieved after 03 days of fermentation using cassava starch. After salt precipitation, fold purification of α-amylase and amyloglucosidase increased up to 4.1 and 4.2 times with specific activity of 9.2 kUmg⻹ and 393 kUmg⻹, respectively. Concentrated amylolytic enzyme mixture was incorporated in cassava starch slurry to give maximum glucose formation (40.0 gL⻹), which was further fermented using Saccharomyces cerevisiae into bioethanol with 84.0% yield. The distillate originated after recovery of bioethanol gave 53.0% yield. CONCLUSION: An improved and effective dual enzymatic starch degradation method is designed for the production of bioethanol using cassava starch. The technique developed is more profitable due to its fast liquefaction and saccharification approach that was employed for the formation of glucose and ultimately resulted in higher yields of alcohol production.
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Biocombustíveis , Etanol/metabolismo , Glucana 1,4-alfa-Glucosidase/metabolismo , Manihot/metabolismo , Amido/metabolismo , alfa-Amilases/metabolismo , Aspergillus fumigatus/enzimologia , Técnicas de Cultura Celular por Lotes , Glucose/metabolismo , Saccharomyces cerevisiae/metabolismoRESUMO
Pakistan, among the top five most water-stressed nations globally, grapples with water scarcity owing to inadequate treatment infrastructure and groundwater overextraction. We demonstrate a successful nature-based closed-loop system to treat wastewater from urban vehicle-washing facilities, previously reliant on groundwater. An eco-friendly integrated system containing floating treatment wetlands (FTWs), subsurface flow constructed wetlands (SSF-CWs), and sand filtration (SF) was designed and installed at three vehicle-washing facilities for wastewater treatment and reuse in a loop. While the system is still operational after years, a consistent and significant reduction in water quality indicators is recorded, successfully meeting the national environmental quality standards of Pakistan. By reducing per unit water treatment costs to as low as $0.0163/m³ and achieving payback periods under a year, the embrace of these closed-loop strategies vividly underscores the imperative of transitioning to a circular economy in the domains of wastewater treatment and resource conservation.
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PURPOSE: The Veterans Health Administration (VHA) employed implementation facilitation (IF) as a strategy to boost uptake of intimate partner violence (IPV) screening programs in primary care. This study examined the sustainment of screening uptake 1 year after IF and identified factors impacting sustainment success. METHODS: A mixed-methods evaluation using quantitative and qualitative data was conducted. IPV screening rates from the conclusion of the IF period (i.e., initial adoption) through the 1-year sustainment period served as the primary outcome. We categorized sites into four groups of screening adoption and sustainment success (high adoption and high sustainment, moderate adoption and moderate sustainment, low adoption and low sustainment, and no adoption and/or no sustainment). Qualitative analysis of key informant interviews was used to identify contextual factors affecting screening 12 months post-IF. A mixed sustainment analysis matrix integrated quantitative and qualitative findings and enabled the identification of cross-site patterns. MAIN FINDINGS: Seven of the nine sites sustained IPV screening at the most basic level (saw static or increased screening rates). High adopting and high sustaining sites (n = 3) were marked by consistently supportive medical center leadership, ongoing training for clinicians, clear protocols for responding to positive screens, and robust referral options for women experiencing IPV. Nonsustaining sites (n = 2) were marked by a host of barriers including staffing shortages, competing priorities, and inconsistent messaging from leadership regarding the importance of IPV screening. CONCLUSIONS: Knowing barriers and facilitators to successful IPV screening sustainment can inform health care systems to tailor IF and other implementation strategies to sustain IPV screening in primary care. Sustainment of IPV screening requires attention to a combination of facilitators (e.g., consistent leadership support and robust referral options) as well as addressing key barriers (e.g., staff turnover and competing priorities).
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Residual antibiotics have become emerging contaminants of concern for their adverse impact on the ecosystem. Additionally, their accumulation in the environment is increasing antibiotic resistance among pathogens. This study assessed the impact of intensification of biochar, nutrients, aeration, and bacteria (BNAB) on the remediation potential of floating treatment wetlands (FTWs) to treat amoxicillin (AMX)-contaminated water. The FTWs were developed with saplings of Vetiveria zizanioides and intensified with biochar (1.5%), nutrients (25 mgL-1 N, 25 mgL-1 P, 20 mg L1 K), aeration (7 mg L-1), and AMX-degrading bacteria. The results showed that all the amendments enhanced the AMX degradation, while the maximum reduction in COD (89%), BOD (88%), TOC (87%), and AMX (97%) was shown by the combined application of all the amendments. The combined application also enhanced plant growth and persistence of the inoculated bacteria in the water, roots, and shoots. This approach can be employed for the low-cost, environment-friendly treatment, and recycling of antibiotic-contaminated wastewater, where BNAB intensification can further improve the bioremediation efficiency of FTWs in the case of heavily polluted waters.
Vetiver grass floating treatment wetlands (FTWs) removed 83% amoxicillin.Intensification of floating treatment wetlands enhanced amoxicillin removal to 97%.Intensified-FTW removed COD, BOD, and TOC by 89%, 88%, and 87%, respectively.Potential of Intensified-FTW for bioremediation of highly polluted water is shown.
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Amoxicilina , Antibacterianos , Áreas Alagadas , Ecossistema , Anticorpos Amplamente Neutralizantes , Nutrientes , Bactérias , ÁguaRESUMO
BACKGROUND: Intimate partner violence (IPV) is a prevalent social determinant of health. The US Preventive Services Task Force recommends routine IPV screening of women, but uptake remains variable. The Veterans Health Administration (VHA) initiated implementation facilitation (IF) to support integration of IPV screening programs into primary care clinics. An evaluation of IF efforts showed variability in IPV screening rates across sites. The follow-up study presented here used a Matrixed Multiple Case Study (MMCS) approach to examine the multilevel factors impacting IPV screening program implementation across sites with varying levels of implementation success. METHODS: This mixed methods study is part of a larger cluster randomized stepped wedge Hybrid-II program evaluation. In the larger trial, participating sites received 6 months of IF consisting of an external facilitator from VHA's Office of Women's Health working closely with an internal facilitator and key site personnel. Recognizing the heterogeneity in implementation outcomes across sites, the MMCS approach was used to enable interpretation of qualitative and quantitative data within and across sites to help contextualize the primary findings from the larger study. Qualitative data collection was guided by the integrated Promoting Action on Research Implementation in Health Services (i-PARIHS) framework and included interviews with key informants involved in IPV screening implementation at eight sites. Quantitative data on IPV screening uptake was derived from medical records and surveys completed by key personnel at the same eight sites to understand implementation facilitation activities. RESULTS: Fifteen factors influencing IPV screening implementation spanning all four i-PARIHS domains were identified and categorized into three distinct categories: (1) factors with enabling influence across all sites, (2) factors deemed important to implementation success, and (3) factors differentiating sites with high/medium versus low implementation success. CONCLUSIONS: Understanding the influencing factors across multi-level domains contributing to variable success of IPV screening implementation can inform the tailoring of IF efforts to promote spread and quality of screening. Implementation of IPV screening programs in primary care with IF should consider consistent engagement of internal facilitators with clinic staff involved in implementation, the resourcefulness of external facilitators, and appending resources to IPV screening tools to help key personnel address positive screens. TRIAL REGISTRATION: ClinicalTrials.gov NCT04106193. Registered on September 26, 2019.
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INTRODUCTION: The Veterans Health Administration initiated implementation facilitation to integrate intimate partner screening programs in primary care. This study investigates implementation facilitation's impact on implementation and clinical effectiveness outcomes. STUDY DESIGN: A cluster randomized, stepped-wedge, hybrid-II implementation-effectiveness trial (January 2021-April 2022) was conducted amidst the COVID-19 pandemic. SETTING/PARTICIPANTS: Implementation facilitation was applied at 9 Veterans Health Administration facilities, staged across 2 waves. Participants were all women receiving care at participating primary care clinics 3 months before (pre-implementation facilitation n=2,272) and 9 months after initiation of implementation facilitation (implementation facilitation n=5,149). INTERVENTION: Implementation facilitation included an operations-funded external facilitator working for 6 months with a facility-funded internal facilitator from participating clinics. The pre-implementation facilitation period comprised implementation as usual in the Veterans Health Administration. MAIN OUTCOME MEASURES: Primary outcomes were changes in (1) reach of intimate partner violence (IPV) screening programs among eligible women (i.e., those seen within participating clinics during the assessment period; implementation outcome) and (2) disclosure rates among screened women (effectiveness outcome). Secondary outcomes included disclosure rates among all eligible women and post-screening psychosocial service use. Administrative data were analyzed. RESULTS: For primary outcomes, women seen during the implementation facilitation period were nearly 3 times more likely to be screened for IPV than women seen during the pre-implementation facilitation period (OR=2.70, 95% CI=2.46, 2.97). Women screened during the implementation facilitation period were not more likely to disclose IPV than those screened during the pre-implementation facilitation period (OR=1.14, 95% CI=0.86, 1.51). For secondary outcomes, owing to increased reach of screening during implementation facilitation, women seen during the implementation facilitation period were more likely to disclose IPV than those seen during the pre-implementation facilitation period (OR=2.09, 95% CI=1.52, 2.86). Women screened during implementation facilitation were more likely to use post-screening psychosocial services than those screened during pre-implementation facilitation (OR=1.29, 95% CI=1.06, 1.57). CONCLUSIONS: Findings indicate that implementation facilitation may be a promising strategy for increasing the reach of IPV screening programs in primary care, thereby increasing IPV detection and strengthening connections to support services among the patient population. TRIAL REGISTRATION: This study is registered at www. CLINICALTRIALS: gov NCT04106193.
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COVID-19 , Violência por Parceiro Íntimo , Feminino , Humanos , Pandemias , Violência por Parceiro Íntimo/prevenção & controle , Resultado do Tratamento , Atenção Primária à SaúdeRESUMO
Bacteriocins are peptides produced by a variety of different microbes and have antimicrobial activity against closely related species. These antimicrobial agents are gaining more and more attention as an alternative therapeutics not only in pharmaceutical but also as a preservative in food industries. In this study several bacterial strains were isolated from soil and screened for bacteriocin production. Among them, one strain identified as Bacillus subtilis KIBGE IB-17 on the basis of taxonomic studies and confirmed by 16S rDNA analysis. This newly isolated strain showed antibacterial activity against several Gram positive and Gram negative bacteria. Different concentrations of tryptone, yeast extract and NaCl and physiochemical factors such as temperature, pH and incubation period were selected as variables for maximum production of bacteriocin by using agar well diffusion method and significant effects of variables were observed on the production of Bac-IB17. A newly designed modified TY medium showed maximum bacteriocin production containing 1.0% tryptone, 0.5% yeast extract and 0.5% NaCl. Maximum Bac-IB17 production was observed at 37° after 24 hours with initial medium pH 7.0. Bacillus subtilis KIBGE IB-17 is capable of producing a bacteriocin at a wide range of pH and temperature that makes it an ideal strain that can be used for the production of bacteriocin on industrial scale level. The identification and production of such bacteriocin like compound against a wide spectrum of microbial species is very important for food and pharmaceutical industry.
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Bacillus subtilis/metabolismo , Bacteriocinas , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Antibacterianos/biossíntese , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus subtilis/genética , Bacteriocinas/biossíntese , Bacteriocinas/isolamento & purificação , Bacteriocinas/farmacologia , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana/métodos , Análise de Sequência de DNA/métodos , TemperaturaRESUMO
Ciprofloxacin (CFX) is a broad-spectrum fluoroquinolone antibiotic that is widely used to treat bacterial infections in humans and other animals. However, its unwanted occurrence in any (eco)system can affect nontarget bacterial communities, which may also impair the performance of the natural or artificially established bioremediation system. The problem could be minimized by optimization of operational parameters via modeling of multifactorial tests. To this end, we used a Box-Behnken design in response surface methodology (RSM) to generate the experimental layout for testing the effect of the CFX biodegradation for four important parameters, that is, temperature (°C), pH, inoculum size (v/v %), and CFX concentration (mg L-1). For inoculation, a consortium of three bacterial strains, namely, Acenitobacter lwofii ACRH76, Bacillus pumilus C2A1, and Mesorihizobium sp. HN3 was used to degrade 26 mg L-1 of CFX. We found maximum degradation of CFX (98.97%; initial concentration of 25 mg L-1) at 2% inoculum size, 7 pH, and 35 °C of temperature in 16 days. However, minimum degradation of CFX (48%; initial concentration of 50 mg L-1) was found at pH 6, temperature 30 °C, and inoculum size 1%. Among different tested parameters, pH appears to be the main limiting factor for CFX degradation. Independent factors attributed 89.37% of variation toward CFX degradation as revealed by the value of the determination coefficient, that is, R 2 = 0.8937. These results were used to formulate a mathematical model in which the computational data strongly correlated with the experimental results. This study showcases the importance of parameter optimization via RSM for any bioremediation studies particularly for antibiotics in an economical, harmless, and eco-friendly manner.
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Taking cognizance of the medicinal significance and diverse functions of synthetic Morita-Baylis-Hillman adducts (MBHA), the title ligand was synthesized and purified through column chromatography. Cr+3, Mn+2, Co+3, Ni+2, Cu+2 complexes of the ligand were synthesized under basic conditions, subjected to characterization through spectral analyses and verified with the IR spectrum that was generated computationally by the DFT B3LYP method, with 6-311++ G (d,p) basis set and Hartree Fock (HF) B3LYP method in conjunction with 3-21G(d,p) basis set. Powder XRD helped to testify crystals of the complexes. Moreover, the antibacterial, and antioxidant characteristics of MBHA and its complexes were also established. All of them were found to be active antioxidants. The antibacterial activities, examined against S. aureus, E. coli, B. pumilis and S. typhi have revealed that its Cobalt complex has an excellent potential to act against all of them. Hence, these compounds maybe having potentialities for the discovery of new, cheaper and efficient drugs against various infectious diseases. The study also uncovers the first example of utilization of MBHA towards metal complex formation.
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Complexos de Coordenação , Acrilatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Cobalto/química , Escherichia coli , Ligantes , Testes de Sensibilidade Microbiana , Bases de Schiff/química , Staphylococcus aureusRESUMO
The application of floating treatment wetlands (FTWs) is an innovative nature-based solution for the remediation of polluted water. The rational improvement of water treatment via FTWs is typically based on multifactorial experiments which are labor-intensive and time-consuming. Here, we used the response surface methodology (RSM) for the optimization of FTW's operational parameters for the remediation of water polluted by crude oil. The central composite design (CCD) of RSM was used to generate the experimental layout for testing the effect of the variables hydrocarbon, nutrient, and surfactant concentrations, aeration, and retention time on the hydrocarbon removal in 50 different FTW test systems planted with the common reed, Phragmites australis. The results from these FTW were used to formulate a mathematical model in which the computational data strongly correlated with the experimental results. The operational parameters were further optimized via modeling prediction plus experimental validation in test FTW systems. In the FTW with optimized parameters, there was a 95% attenuation of the hydrocarbon concentration, which was very close to the 98% attenuation predicted by the model. The cost-effectiveness ratio showed a reduction of the treatment cost up to $0.048/liter of wastewater. The approach showed that RSM is a useful strategy for designing FTW experiments and optimizing operational parameters.
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Petróleo , Poluentes Químicos da Água , Biodegradação Ambiental , Hidrocarbonetos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Áreas AlagadasRESUMO
AllyMax is a widely used herbicide formulation in wheat-rice cropping areas of the world. The residues of its active ingredients, tribenuron methyl (TBM) and metsulfuron methyl (MET), persist in soil and water as co-contaminants, and cause serious threats to nontarget organisms. This study was performed to assess the potential of a bacterial consortium for the degradation and detoxification of TBM and MET individually and as co-contaminants. A bacterial consortium (B2R), comprising Bacillus cereus SU-1, Bacillus velezensis OS-2, and Rhodococcus rhodochrous AQ1, capable of degrading TBM and MET in liquid cultures was developed. Biodegradation of TBM and MET was optimized using the Taguchi design of experiment. Optimum degradation of both TBM and MET was obtained at pH 7 and 37 °C. Regarding media composition, optimum degradation of TBM and MET was obtained in minimal salt medium (MSM) supplemented with glucose, and MSM without glucose, respectively. The consortium simultaneously degraded TBM and MET (94.8 and 80.4%, respectively) in cultures containing the formulation AllyMax, where TBM and MET existed as co-contaminants at 2.5 mg/L each. Mass spectrometry analysis confirmed that during biodegradation, TBM and MET were metabolized into simpler compounds. Onion (Allium cepa) root inhibition and Comet assays revealed that the bacterial consortium B2R detoxified TBM and MET separately and as co-contaminants. The consortium B2R can potentially be used for the remediation of soil and water co-contaminated with TBM and MET.
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Background: Many primary care providers (PCPs) in the Veterans Health Administration need updated clinical training in women's health. The objective was to design, implement, and evaluate a training program to increase participants' comfort with and provision of care to women Veterans, and foster practice changes in women's health care at their local institutions. Methods: The Women's Health Mini-Residency was developed as a multi-day training program, based on principles of adult learning, wherein knowledge gleaned through didactic presentations was solidified during small-group case study discussions and further enhanced by hands-on training and creation of a facility-specific action plan to improve women Veterans' care. Pre, post, and 6-month surveys assessed attendees' comfort with and provision of care to women. The 6-month survey also queried changes in practice, promulgation of program content, and action plan progress. Results: From 2008 to 2019, 2912 PCPs attended 26 programs. A total of 2423 (83.2%) completed pretraining and 2324 (79.3%) completed post-training surveys. The 6-month survey was sent to the 645 attendees from the first 14 programs; 297 (46.1%) responded. Comparison of pre-post responses indicated significant gains in comfort managing all 19 content areas. Six-month data showed some degradation, but comfort remained significantly improved from baseline. At 6 months, participants also reported increases in providing care to women, including performing more breast and pelvic examinations, dissemination of program content to colleagues, and progress on action plans. Conclusions: This interactive program appears to have been successful in improving PCPs' comfort in providing care for women Veterans and empowering them to implement institutional change.
Assuntos
Internato e Residência , Veteranos , Adulto , Feminino , Humanos , Atenção Primária à Saúde , Estados Unidos , United States Department of Veterans Affairs , Saúde dos Veteranos , Saúde da MulherRESUMO
Metribuzin (MB), a triazinone herbicide is extensively sprayed for weed control in agriculture, has been reported to contaminate soil, groundwater, and surface waters. In soil, MB residues can negatively affect not only the germination of subsequent crops but also disturb soil bacterial community. The present study describes the use of biochar as a carrier material to immobilize MB-degrading bacterial consortium, for remediation of MB-contaminated soil and restoration of soil bacterial community in soil microcosms. The bacterial consortium (MB3R) comprised four bacterial strains, i.e., Rhodococcus rhodochrous AQ1, Bacillus tequilensis AQ2, Bacillus aryabhattai AQ3, and Bacillus safensis AQ4. Significantly higher MB remediation was observed in soil augmented with bacterial consortium immobilized on biochar compared to the soil augmented with un-immobilized bacterial consortium. Immobilization of MB3R on biochar resulted in higher MB degradation rate (0.017 Kd-1) and reduced half-life (40 days) compared to 0.010 Kd-1 degradation rate and 68 day half-life in treatments where un-immobilized bacterial consortium was employed. It is worth mentioning that the MB degradation products metribuzin-desamino (DA), metribuzin-diketo (DK), and metribuzin desamino-diketo (DADK) were detected in the treatments where MB3R was inoculated either alone or in combination with biochar. MB contamination significantly altered the composition of soil bacteria. However, soil bacterial community was conserved in response to augmentation with MB3R immobilized on biochar. Immobilization of the bacterial consortium MB3R on biochar can potentially be exploited for remediation of MB-contaminated soil and protecting its microbiota.