A nature-based closed-loop wastewater treatment system at vehicle-washing facilities: From linear to circular economy.

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.

Exploring the potential of bacterial-augmented floating treatment wetlands for the remediation of detergent-contaminated water.

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.

Using the Matrixed Multiple Case Study approach to identify factors affecting the uptake of IPV screening programs following the use of implementation facilitation.

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.

Improved remediation of amoxicillin-contaminated water by floating treatment wetlands intensified with biochar, nutrients, aeration, and antibiotic-degrading bacteria.

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.

Integrating Intimate Partner Violence Screening Programs in Primary Care: Results from a Hybrid-II Implementation-Effectiveness RCT.

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.

Response Surface Methodology for Optimization of Operational Parameters To Remove Ciprofloxacin from Contaminated Water in the Presence of a Bacterial Consortium.

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.

Synthesis, Characterization, Biological Activities and Ab-initio Study of Transition Metal Complexes of [Methyl 2-((4-chlorophenyl)(hydroxy)methyle) Acrylate].

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.

Biodegradation and Subsequent Toxicity Reduction of Co-contaminants Tribenuron Methyl and Metsulfuron Methyl by a Bacterial Consortium B2R.

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.

Operational parameters optimization for remediation of crude oil-polluted water in floating treatment wetlands using response surface methodology.

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.

Mini-Residencies to Improve Care for Women Veterans: A Decade of Re-Educating Veterans Health Administration Primary Care Providers.

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.

Immobilization of metribuzin-degrading bacteria on biochar: Enhanced soil remediation and bacterial community restoration.

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.

Intimate Partner Violence Screening for Women in the Veterans Health Administration: Temporal Trends from the Early Years of Implementation 2014-2020.

Thousands of women Veterans experience intimate partner violence (IPV) each year. The Veterans Health Administration (VHA) has encouraged IPV screening in Veterans Affairs medical centers (VAMCs) since 2014. Through retrospective analysis of VHA administrative data from fiscal year (FY) 2014 into FY2020, we examined IPV screening implementation outcomes of reach and adoption, as well as screen-positive rates using descriptive and multivariate linear regression analyses. We examined reach and screen-positive rates overall and as a function of childbearing age (18-44 vs. 45+ years). In FY2014 only one VAMC was screening women for IPV; by FY2020, over half of VAMCs had adopted IPV screening. This rollout of IPV screening was associated with a large increase in the number of women primary care patients screened (from fewer than 500 in FY2014, to nearly 35,000 in early FY2020). Overall, among women screened, 6.7% screened positive for IPV; this rate was higher among women of childbearing age (8.1% vs. 5.6%). Despite the spread of IPV screening practices during the early years of implementation in VHA, additional work is needed. This study is the first comprehensive analysis of implementation outcomes associated with VHA's IPV screening efforts, and lays the groundwork for ongoing evaluation and quality improvement.

Purification and characterization of ß-galactosidase from Aspergillus fumigatus PCSIR-2013.

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.

Investigating degradation metabolites and underlying pathway of azo dye "Reactive Black 5" in bioaugmented floating treatment wetlands.

The direct discharge of azo dyes and/or their metabolites into the environment may exert toxic, mutagenic, and carcinogenic effects on exposed fauna and flora. In this study, we analyzed the metabolites produced during the degradation of an azo dye namely Reactive Black 5 (RB5) in the bacterial-augmented floating treatment wetlands (FTWs), followed by the investigation of their underlying toxicity. To this end, a FTWs system was developed by using a common wetland plant Phragmites australis in the presence of three dye-degrading bacteria (Acinetobacter junii strain NT-15, Pseudomonas indoloxydans strain NT-38, and Rhodococcus sp. strain NT-39). We found that the FTW system effectively degraded RB5 into at least 20 different metabolites with the successful removal of color (95.5%) from the water. The fish toxicity assay revealed the nontoxic characteristics of the metabolites produced after dye degradation. Our study suggests that bacterially aided FTWs could be a suitable option for the successful degradation of azo dyes, and the results presented in this study may help improve the overall textile effluent cleanup processes.

Immobilization of metribuzin degrading bacterial consortium MB3R on biochar enhances bioremediation of potato vegetated soil and restores bacterial community structure.

Metribuzin (MB) is a triazinone herbicide used for the eradication of weeds in agriculture. Presence of its residues in agricultural soil can potentially harm the establishment of subsequent crops and structure of soil microbial populations. In this study, remediation potential of an MB degrading bacterial consortium MB3R immobilized on biochar was evaluated in potato vegetated soil. In potato vegetated soil augmented with MB3R alone and MB3R immobilized on biochar, 82 and 96% MB degradation was recorded respectively as compared to only 29.3% in un-augmented soil. Kinetic parameters revealed that MB3R immobilized biochar is highly proficient as indicated by significant increase in the rate of biodegradation and decrease in half-life of MB. Enhanced plant growth was observed when augmented with bacterial consortium either alone or immobilized on biochar. Presence of herbicide negatively affected the soil bacterial community structure. However, MB3R immobilized on biochar proved to be helpful for restoration of soil bacterial community structure affected by MB. This is the very first report that reveals improved remediation of contaminated soil and restoration of soil bacterial populations by use of the MB degrading bacterial consortium immobilized on biochar.

Phragmites australis in combination with hydrocarbons degrading bacteria is a suitable option for remediation of diesel-contaminated water in floating wetlands.

The presence of diesel in the water could reduce the growth of plant and thus phytoremediation efficacy. The toxicity of diesel to plant is commonly explained; because of hydrocarbons in diesel accumulate in various parts of plants, where they disrupt the plant cell especially, the epidemis, leaves, stem and roots of the plant. This study investigated the effect of bacterial augmentation in floating treatment wetlands (FTWs) on remediation of diesel oil contaminated water. A helophytic plant, Phragmites australis (P. australis), was vegetated on a floating mat to establish FTWs for the remediation of diesel (1%, w/v) contaminated water. The FTWs was inoculated with three bacterial strains (Acinetobacter sp. BRRH61, Bacillus megaterium RGR14 and Acinetobacter iwoffii AKR1), possessing hydrocarbon degradation and plant growth-enhancing capabilities. It was observed that the FTWs efficiently removed hydrocarbons from water, and bacterial inoculation further enhanced its hydrocarbons degradation efficacy. Diesel contaminated water samples collected after fifteen days of time interval for three months and were analyzed for pollution parameters. The maximum reduction in hydrocarbons (95.8%), chemical oxygen demand (98.6%), biochemical oxygen demand (97.7%), total organic carbon (95.2%), phenol (98.9%) and toxicity was examined when both plant and bacteria were employed in combination. Likewise, an increase in plant growth was seen in the presence of bacteria. The inoculated bacteria showed persistence in the water, root and shoot of P. australis. The study concluded that the augmentation of hydrocarbons degrading bacteria in FTWs is a better option for treatment of diesel polluted water.

Remediation of textile bleaching effluent by bacterial augmented horizontal flow and vertical flow constructed wetlands: A comparison at pilot scale.

Fabric bleaching is one of the most widely used processes of the textile industry that also produces a significant amount of highly polluted wastewater. Previously, expensive and chemically extensive conventional remediation systems were used to treat bleaching effluent. Despite this, the potential of constructed wetlands (CWs) as a treatment system remains un-investigated. Furthermore, most research on the use of CWs for textile effluents are conducted at laboratory scale and therefore further research at field-scale is timely. This study compares the efficacy of bacterial augmented vertical flow constructed wetlands (VFCWs) and horizontal flow constructed wetlands (HFCWs) for the remediation of textile bleaching wastewater at pilot scale. To this end, CWs macrocosms of 1000 L water capacity were planted with Phragmites australis and inoculated with bacterial strains possessing pollutant degradation and plant growth-promoting traits. The results showed that both variants of CWs were effective in attenuating pollutants from the wastewater; however, the performance of HFCWs exceeded that of the VFCWs for almost every pollutant measure undertaken. For HFCWs, a significant reduction in COD (89%), BOD (91%), TOC (96%), and toxicity was achieved in a period of 72 h during the first month of operation. Bacterial inoculation in CWs further improved the system's performance and these bacteria also exhibited persistence in the rhizoplane (43%), root interior (56%) and shoot interior (29%) of P. australis. This study, therefore, suggests that the bacterial augmented HFCWs is a suitable approach for industrial scale textile bleach wastewater treatment.

Application of a novel bacterial consortium BDAM for bioremediation of bispyribac sodium in wheat vegetated soil.

Plant-bacterial mutualism has tremendous potential for remediation of herbicide contaminated soils. Generally, bacterial inoculation helps plants to grow well in the contaminated environment. Here, we investigated the impact of bispyribac sodium (BS) degrading bacterial consortium (BDAM) on BS remediation, plant growth promotion and BS accumulation in plant parts. Wheat (Triticum aestivum) was planted in BS spiked soil and inoculated with BDAM. Inoculation showed a beneficial effect on plant biomass production and degradation of BS in the rhizosphere and the rhizosheath. After 40 and 60 days of inoculation, the degradation of BS was more than 96% and approximately 100% respectively in the planted and inoculated soil spiked with 2 and 5 mg kg-1 BS. However, in planted and un-inoculated soil, the degradation of BS was 72% after 60 days of sowing. Furthermore, inoculated bacterial strains colonized both in rhizo- and endosphere of the inoculated plants. In comparison with the un-inoculated soil, significantly less accumulation of BS was found in the roots and shoots of the plants growing in inoculated soil. We report the efficiency of plant-bacterial partnership for enhanced biodegradation of BS and to eliminate the BS residual toxicity to non-target plants.

Enhanced degradation of hydrocarbons by gamma ray induced mutant strain of Pseudomonas putida.

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.

Optimizing the metribuzin degrading potential of a novel bacterial consortium based on Taguchi design of experiment.

Metribuzin (MB) is used for control of weeds in crops like potato, maize and sugarcane. Its extensive and unjudicial use has resulted in various environmental issues; hence it is very critical to remediate this herbicide at the respective point source. Plant associated, MB degrading bacterial strains, Rhodococcus rhodochrous sp. AQ1, Bacillus tequilensis sp. AQ2, Bacillus aryabhattai sp. AQ3 and Bacillus safensis sp. AQ4 were isolated, and a consortium MB3R was developed. For degradation of MB by the consortium MB3R, various parameters i.e., pH, temperature, inoculum density and pesticide concentration were optimized by using Taguchi design of experiment (DOE). MB degradation was dependent upon all the four factors. The contribution of each factor on MB degradation was according to the order: temperature > inoculum density > pH > pesticide concentration. Fitness of Taguchi DOE in forecasting the optimum response, was confirmed experimentally by using optimized levels of the four factors i.e., pH 7.0, temperature 30 °C, pesticide concentration 45 mg l-1 and an inoculum density of 5.0 × 10 5 CFU ml-1 whereby 98.63% MB degradation was observed. Appearance and subsequent degradation of three MB metabolites, desamino-metribuzin (DA), diketo-metribuzin (DK) and desamino-diketo-metribuzin (DADK) during biodegradation by the consortium was observed.