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1.
Gen Psychiatr ; 36(5): e101014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37859749

RESUMEN

Background: Avoidant paruresis is a common clinical condition in urology and psychosomatic medicine. However, it has limited treatment options that are safe and effective with few side effects. Aims: Our study aimed to investigate the effectiveness and safety of the Chinese herbal Yangxin Tongquan decoction combined with cognitive-behavioural therapy (CBT) for avoidant paruresis. Methods: Sixty-eight patients with avoidant paruresis were divided into a treatment group (33 patients) and a control group (35 patients). The control group was assigned 10 weeks of CBT and systematic desensitisation. In addition to CBT and systematic desensitisation, the treatment group was given the Chinese herbal Yangxin Tongquan decoction during the 10-week study. The Shy Bladder Syndrome Scale (SBS) and the Self-rating Anxiety Scale (SAS) were administered before and after treatment to measure any change. Results: The overall efficacy in the treatment group (n=30) was 80.0% vs 62.5% in the control group (n=33). Comparing pretreatment and post-treatment measures, both groups showed improvement in SBS scores and SAS scores (treatment group: t(SBS) =8.397, p(SBS) <0.001, t(SAS) =8.216, p(SAS)<0.001; control group: t(SBS) =6.802, p(SBS) <0.001, t(SAS)=5.171, p(SAS) <0.001). Moreover, both groups' SBS and SAS scores changed significantly over time (SBS scores: Ftime =118.299, p<0.001; SAS scores: Ftime =92.114, p<0.001). However, the treatment group performed better than the control group (SBS scores: Ftime*group =5.709, p=0.020; SAS scores: Ftime*group =7.235, p=0.009). Conclusions: The Chinese herbal Yangxin Tongquan decoction combined with cognitive-behavioural psychotherapy positively affects the treatment of avoidant paruresis without significant adverse effects.

2.
J Hazard Mater ; 413: 125392, 2021 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-33609875

RESUMEN

Complexly contaminated river sediment caused by reducible and oxidizable organic pollutants is a growing global concern due to the adverse influence on ecosystem safety and planetary health. How to strengthen indigenous microbial metabolic activity to enhance biodegradation and mineralization efficiency of refractory composite pollutants is critical but poorly understood in environmental biotechnology. Here, a synergetic biostimulation coupling electrode with zero-valent iron (ZVI) was investigated for the bioremediation of river sediments contaminated by 2,4,6-tribromophenol (TBP, reducible pollutant) and hydrocarbons (oxidizable pollutants). The bioremediation efficiency of ZVI based biostimulation coupling electrode against TBP debromination and hydrocarbons degradation were 1.1-3 times higher than the electrode used solely, which was attributed to the shape of distinctive microbial communities and the enrichment of potential dehalogenators (like Desulfovibrio, Desulfomicrobium etc.). The sediment microbial communities were significantly positively correlated with the enhanced degradation efficiencies of TBP and hydrocarbons (P < 0.05). Moreover, the coupled system predominately increased positive microbial interactions in the ecological networks. The possible mutual relationship between microbes i.e., Thiobacillus (iron-oxidizing bacteria) and Desulfovibrio (dehalogenator) as well as Pseudomonas (electroactive bacteria) and Clostridium (hydrocarbons degraders) were revealed. This study proposed a promising approach for efficient bioremediation of complexly contaminated river sediments.


Asunto(s)
Hierro , Ríos , Biodegradación Ambiental , Electrodos , Sedimentos Geológicos
3.
J Hazard Mater ; 403: 123937, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33264985

RESUMEN

Haloaromatic antimicrobial triclocarban (TCC) is an emerging refractory contaminant that commonly coexisted with conventional contaminants such as polycyclic aromatic hydrocarbons (PAHs). TCC may negatively affect the metabolic activity of sediment microorganisms and persist in environment; however, remediation methods that relieve the TCC inhibitory effect in sediments remain unknown. Here, a novel electro-biostimulation and bioaugmentation combined remediation system was proposed by the simultaneous introduction of a TCC-degrading Ochrobactrum sp. TCC-2 and electrode into the TCC and PAHs co-contaminated sediments. Results indicated the PAHs and TCC degradation efficiencies of the combined system were 2.9-3.0 and 4.6 times respectively higher than those of the control group (no electro-biostimulation and no bioaugmentation treatments). The introduced strain TCC-2 and the enriched electroactive bacteria and PAHs degraders (e.g. Desulfobulbus, Clostridium, and Paenarthrobacter) synergistically contributed to the accelerated degradation of PAHs and TCC. The preferential elimination of the TCC inhibitory effect through bioaugmentation treatment could restore microbial functions by increasing the functional gene abundances related to various metabolic processes. This study offers new insights into the response of sediment functional communities to TCC stress, electro-biostimulation and bioaugmentation operations and provides a promising system for the enhanced bioremediation of the PAHs and TCC co-contaminated sediments.


Asunto(s)
Antiinfecciosos , Carbanilidas , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Biodegradación Ambiental , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes del Suelo/análisis
4.
Front Cell Dev Biol ; 9: 764481, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35178395

RESUMEN

Background: Breast cancer (BC) is the leading cause of cancer-related deaths among women worldwide. The application of advanced technology has promoted accurate diagnosis and treatment of cancer. Anhydroicaritin (AHI) is a flavonoid with therapeutic potential in BC treatment. The current study aimed to determine AHI's mechanism in BC treatment via RNA sequencing, comprehensive bioinformatics analysis, and experimental verification. Methods: Network pharmacology and MTT (3-(4,5)-dimethylthiazolyl-3,5- diphenyltetrazolium bromide) experiments were conducted to first confirm AHI's anti-BC effect. RNA sequencing was performed to identify the genes affected by AHI. Differential expression analysis, survival analysis, gene set enrichment analysis, and immune infiltration analysis were performed via bioinformatics analysis. Western blot analysis, reverse transcription-polymerase chain reaction (RT-PCR) experiment, molecular docking, and drug affinity responsive target stability (DARTS) experiments were also performed to confirm AHI's direct effect on glutathione peroxidase 1 (GPX1) expression. Confocal immunofluorescence analysis was conducted to verify AHI's effect on the occurrence and development of epithelial-mesenchymal transition (EMT). Finally, BC nude mouse xenografts were established, and AHI's molecular mechanism on BC was explored. Results: Network pharmacology results demonstrated that AHI's therapeutic targets on BC were related to the proliferation, invasion, and metastasis of BC cells. AHI significantly inhibited the proliferation of 4T1 and MDA-MB-231 BC cells in the MTT experiments. RNA sequencing results showed that AHI upregulated the GPX1 expression in the 4T1 and MDA-MB-231 BC cells. Next, bioinformatics analysis revealed that GPX1 is less expressed in BC than in normal breast tissues. Patients with high GPX1 expression levels tended to have prolonged overall survival and disease-free survival than patients with low GPX1 expression levels in BC. Western blot and RT-PCR experiments revealed that AHI increased the protein and mRNA levels of GPX1. Molecular docking and DARTS experiments confirmed the direct binding combination between AHI and GPX1. After the evaluation of the EMT scores of 1,078 patients with BC, we found a potential anti-BC role of GPX1 possibly via suppression of the malignant EMT. The confocal immunofluorescence analysis showed that AHI increased E-cadherin expression levels and reduced vimentin expression levels in BC cells. Animal experiments showed that AHI significantly inhibited tumor growth. AHI also inhibited EMT by enhancing GPX1 and caspase3 cleavage, hence inhibiting EMT markers (i.e., N-cadherin and vimentin) and Ki-67. Conclusion: GPX1 plays a critical role in BC, which may be a biomarker for the prognosis. In addition, AHI suppressed EMT by increasing GPX1 expression, which may serve as a potential therapy for BC treatment.

5.
Gen Psychiatr ; 33(5): e100184, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32875271

RESUMEN

BACKGROUND: Erectile dysfunction (ED) has gradually become an important issue that seriously affects the quality of life of Chinese men. In addition to classic oral medications, psychotherapeutic interventions are increasingly being used in the treatment of ED. AIM: This study aims to investigate the clinical efficacy of brief psychodynamic psychotherapy (BPP) plus Viagra in the treatment of non-organic ED. METHODS: We initiated this study via a controlled, prospective experimental design with initial optimal efficiency standard greater than 10%. On the standard, 63 patients were enrolled who were assigned to control or treatment group. The control group (including 33 cases) received Viagra treatment for 2 months, and the treatment group (including 30 cases) was cured with BPP plus Viagra. After the treatments, the clinical efficacy was assessed using the International Erectile Function Index (IIEF-5) score, the Self-rating Anxiety Scale (SAS), Sexual Satisfaction (SS) score and Erection Hardness Score (EHS). RESULTS: In the comparison of efficacy, pretreatment and post-treatment within each group, the two groups showed improvements in IIEF, SAS scores, SS, and EHS (treatment group: PIIEF<0.001, PSAS<0.001, PSS<0.001, PEHS<0.001; control group: PIIEF<0.001, PSAS<0.001, PSS<0.001, PEHS<0.001). Furthermore, the treatment group presented better performances in IIEF (p=0.040), SAS (p=0.006), SS scores (p=0.045) and EHS (p=0.041) than the control group. CONCLUSION: The combination of BPP with Viagra has positive effect on the treatment of non-organic ED.

6.
Pharm Biol ; 57(1): 507-513, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31401919

RESUMEN

Context: Bladder cancer, which has high recurrence, is one of the most deadly cancers in the world. Astragalus propinquus Schischkin (Fabaceae) and Sagittaria sagittifolia L. (Alismataceae) are important herbs reported to be effective in cancer therapy. Objective: The efficacy of QCSL (Qici Sanling decoction) in bladder cancer treatment was examined. Materials and methods: T24 cells were injected into the flanks of nude mice and the mice were randomly divided into five groups: control; 20 mg/kg XAV-939 (an inhibitor of the WNT/ß-catenin pathway); QCSL (100, 200, or 400 mg/kg). After 7 weeks, the mice were anaesthetised using isoflurane and the xenografts were excised to perform further experiments. Results: Both XAV-939 (tumour volume: 379.67 ± 159.92 mm3) and QCSL (796.18 ± 101.6 mm3) dramatically suppressed tumour growth comparing with control group (3612.12 ± 575.03 mm3). XAV-939 and QCSL treatments decreased cell proliferation from 56.3 ± 0.05% to 29.02 ± 0.07% and 37.51 ± 0.04%, respectively. In agreement, more infiltration of immune cells and pyknotic cells upon XAV-939 (apoptosis rates: 43.92 ± 0.03%) and QCSL (34.57 ± 0.04%) treatment comparing with control group (15.59 ± 0.03%) were observed. Furthermore, TUNEL staining of xenograft tumours illustrated more apoptotic cells upon XAV-939 and QCSL treatment. Mechanistically, XAV-939 and QCSL treatments significantly inhibited WNT/ß-catenin pathway in T24 xenograft tumours. Discussion and conclusions: Our findings give new insights into the role of QCSL in bladder cancer and explore potential mechanisms contributing to the therapeutic effects of QCSL in bladder cancer.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Neoplasias de la Vejiga Urinaria/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Animales , Apoptosis , Astragalus propinquus , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Compuestos Heterocíclicos con 3 Anillos , Xenoinjertos/efectos de los fármacos , Xenoinjertos/patología , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Sci Total Environ ; 653: 649-657, 2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30759590

RESUMEN

The intense pollution of urban river sediments with rapid urbanization has attracted considerable attention. Complex contaminated sediments urgently need to be remediated to conserve the ecological functions of impacted rivers. This study investigated the effect of using methanol as a co-substrate on the stimulation of the indigenous microbial consortium to enhance the bioremediation of petroleum hydrocarbons (PHs) and polycyclic aromatic hydrocarbons (PAHs) in an urban river sediment. After 65 days of treatment, the PAHs degradation efficiencies in the sediment adding methanol were 4.87%-40.3% higher than the control. The removal rate constant of C31 was 0.0749 d-1 with 100 mM of supplied methanol, while the corresponding rate was 0.0399 d-1 in the control. Four-ring PAHs were effectively removed at a degradation efficiency of 65%-69.8%, increased by 43.3% compared with the control. Sulfate reduction and methanogenesis activity were detected, and methane-producing archaea (such as Methanomethylovorans, with a relative abundance of 25.87%-58.53%) and the sulfate-reducing bacteria (SRB, such as Desulfobulbus and Desulfobacca) were enriched. In addition, the chemolithoautotrophic sulfur-oxidizing bacteria (SOB, such as Sulfuricurvum, with a relative abundance of 34%-39.2%) were predominant after the depletion of total organic carbon (TOC), and markedly positively correlated with the PHs and PAHs degradation efficiencies (P < 0.01). The SRB and SOB populations participated in the sulfur cycle, which was associated with PHs and PAHs degradation. Other potential functional bacteria (such as Dechloromonas) were also obviously enriched and significantly positively correlated with the TOC concentration after methanol injection (P < 0.001). This study provides a new insight into the succession of the indigenous microbial community with methanol as a co-substrate for the enhanced bioremediation of complexly contaminated urban river sediments.


Asunto(s)
Bacterias Anaerobias/crecimiento & desarrollo , Sedimentos Geológicos/química , Metanol/química , Microbiota/efectos de los fármacos , Ríos/química , Contaminantes Químicos del Agua/metabolismo , Bacterias Anaerobias/metabolismo , Biodegradación Ambiental , China , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/microbiología , Modelos Teóricos , Petróleo/análisis , Petróleo/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/metabolismo , Ríos/microbiología , Urbanización , Contaminantes Químicos del Agua/análisis
8.
Chemosphere ; 222: 149-155, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30703654

RESUMEN

Obtaining efficient antibiotic-mineralizing consortium or pure cultures is a central issue for the deep elimination of antibiotic-contaminated environments. However, the antibiotic chloramphenicol (CAP) mineralizing consortium has not yet been reported. In this study, an efficient CAP-mineralizing consortium was successfully obtained with municipal activated sludge as the initial inoculum. This consortium is capable of aerobically subsisting on CAP as the sole carbon, nitrogen and energy sources and completely degrading 50 mg L-1 CAP within 24 h. After 5 d, 71.50 ±â€¯2.63% of CAP was mineralized and Cl- recovery efficiency was 90.80 ±â€¯7.34%. Interestingly, the CAP degradation efficiency obviously decreased to 18.22 ±â€¯3.52% within 12 h with co-metabolic carbon source glucose. p-nitrobenzoic acid (p-NBA) was identified as an intermediate product during CAP biodegradation. The consortium is also able to utilize p-NBA as the sole carbon and nitrogen sources and almost completely degrade 25 mg L-1p-NBA within 24 h. Microbial community analysis indicated that the dominant genera in the CAP-mineralizing consortium all belong to Proteobacteria (especially Sphingobium with the relative abundance over 63%), and most bacteria could degrade aromatics including p-NBA, suggesting these genera involved in the upstream and downstream pathway of CAP degradation. Although the acclimated consortium has been successively passaged 152 times, the microbial community structure and core genera were not obviously changed, which was consistent with the stable CAP degradation efficiency observed under different generations. This is the first report that the acclimated consortium is able to mineralize CAP through an oxidative pathway with p-NBA as an intermediate product.


Asunto(s)
Antibacterianos/metabolismo , Cloranfenicol/metabolismo , Consorcios Microbianos , Sphingomonadaceae/metabolismo , Biodegradación Ambiental , Carbono/metabolismo , Nitrobenzoatos/metabolismo , Nitrógeno/metabolismo , Aguas del Alcantarillado/microbiología
9.
Water Res ; 148: 398-406, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30399554

RESUMEN

Understanding the fate of overall antibiotic resistance genes (ARGs) during the biological treatment of antibiotic containing wastewater is a central issue for the water ecological safety assessment. Although the microbial electrode-respiration based biotransformation process could significantly detoxify some antibiotic contaminants, e.g. chloramphenicol (CAP), the response of CAP-reducing biocathode microbiome and resistome to continuous electrical stimulation, especially ARGs network interactions, are poorly understood. Here, using highthroughput functional gene array (GeoChip v4.6) and Illumina 16S rRNA gene MiSeq sequencing, the structure, composition, diversity and network interactions of CAP-reducing biocathode microbiome and resistome in response to continuous electrical stimulation were investigated. Our results indicate that the CAP bioelectroreduction process could significantly accelerate the elimination of antibacterial activity of CAP during CAP-containing wastewater treatment compared to the pure bioreduction process. Continuous electrical stimulation could obviously alter both the microbiome and resistome structures and consistently decrease the phylogenetic, functional and overall ARGs diversity and network complexity within the CAP-reducing biofilms. The relative abundances of overall ARGs and specific CAP resistance related major facilitator superfamily (MFS) transporter genes were significantly negatively correlated with the reduction efficiency of CAP to inactive antibacterial product AMCl (partially dechlorinated aromatic amine), which may reduce the ecological risk associated with the evolution of multidrug-resistant bacteria and ARGs during antibiotic-containing wastewater treatment process. This study offers new insights into the response of an antibiotic reducing biocathode resistome to continuous electrical stimulation and provides useful information on the assessment of overall ARGs risk for the bioelectrochemical treatment of antibiotic contaminants.


Asunto(s)
Antibacterianos , Cloranfenicol , Farmacorresistencia Microbiana , Estimulación Eléctrica , Genes Bacterianos , Filogenia , ARN Ribosómico 16S
10.
Chemosphere ; 202: 105-110, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29554502

RESUMEN

The bioelectrotransformation efficiency of various organic matters and corresponding electrode biofilm community formation as well as electron transfer efficiency in bioelectrochemical systems (BESs) with different modified electrodes has been extensively studied on the anode side. However, the effects of cathode interface characteristics towards the BESs bioelectrotransformation performance remain poorly understood. In this study, the nitrobenzene-reducing biocathode catalytic efficiency and community structure in response to different modified electrodes (control: hydrophobic and no charge; -SH: hydrophobic and single negative charge; -NH2: hydrophilic and single positive charge -NH-NH2: hydrophilic and double positive charges) were investigated. The biocathode transformation efficiency of nitrobenzene (NB) to aniline (AN) (ENB-AN) was affected by the nature of electrode interface as well as the biocathode community formation and structure. Cathodes with hydrophilic surface and positive charges have performed well in the bioelectrotransformation experiments, and especially made an outstanding performance when inorganic NaHCO3 was supplied as carbon source and cathode as the sole electron donor. Importantly, the hydrophilic surfaces with positive charges were dominated by the electroactive nitroaromatic reducers (Enterococcus, Desulfovibrio and Klebsiella) with the relative abundance as high as 72.20 ±â€¯1.87% and 74.86 ±â€¯8.71% for -NH2 and -NH-NH2 groups respectively. This could explain the higher ENB-AN in the hydrophilic groups than that of the hydrophobic -SH modified group. This study provides new insights into the effects of electrode interface characteristics on the BESs biocathode performance and offers some suggestions for the future design for the improvement of bioelectroremediation performance.


Asunto(s)
Compuestos de Anilina/química , Electrodos , Nitrobencenos/química , Catálisis , Interacciones Hidrofóbicas e Hidrofílicas
11.
J Hazard Mater ; 349: 168-176, 2018 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-29421353

RESUMEN

Bioelectroremediation is an efficient, sustainable, and environment-friendly remediation technology for the complexly contaminated sediments. Although various recalcitrant pollutants could be degraded in the electrode district, the degradation efficiency was generally confined by the low total organic carbon (TOC) content in the sediment. How to enhance the electroactive degraders' activity and efficiency remain poorly understood. Here we investigated the bioeletroremediation of a complexly contaminated river sediment with low TOC in a cylindric sediment microbial fuel cell stimulated by methanol. After 200 days treatment, the degradation efficiencies of total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), and cycloalkenes (CYE) in the electrode district with methanol stimulation were 1.45-4.38 times higher compared with those in the non-electrode district without methanol stimulation. The overall electrode district communities were significantly positively correlated with the variables of the enhanced TPH, PAH, CYE and TOC degradation efficiencies (p < .01). The joint electrical and exogenous methanol stimulation selectively enriched electroactive degraders (Geobacter and Desulfobulbus) in the anode biofilms, and their proportion was markedly positively correlated with the characteristic and total pollutants degradation efficiencies (p < .001). This study offers a new insight into the response of key electroactive degraders to the joint stimulation process.


Asunto(s)
Técnicas Electroquímicas , Hidrocarburos/metabolismo , Metanol/farmacología , Contaminantes Químicos del Agua/metabolismo , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Biodegradación Ambiental/efectos de los fármacos , Electrodos/microbiología , Sedimentos Geológicos , Ríos
12.
J Hazard Mater ; 324(Pt A): 48-53, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27045457

RESUMEN

To characterize the impact of influent loading on elemental sulfur (S0) recovery during the denitrifying and sulfide oxidation process, three identical, lab-scale UASB reactors (30cm in length) were established in parallel under different influent acetate/nitrate/sulfide loadings, and the reactor performance and functional community structure were investigated. The highest S0 recovery was achieved at 77.9% when the acetate/nitrate/sulfide loading was set to 1.9/1.6/0.7kgd-1m-3. Under this condition, the genera Thauera, Sulfurimonas, and Azoarcus were predominant at 0-30, 0-10 and 20-30cm, respectively; meanwhile, the sqr gene was highly expressed at 0-30cm. However, as the influent loading was halved and doubled, S0 recovery was decreased to 27.9% and 45.1%, respectively. As the loading was halved, the bacterial distribution became heterogeneous, and certain autotrophic sulfide oxidation genera, such as Thiobacillus, dominated, especially at 20-30cm. As the loading doubled, the bacterial distribution was relatively homogeneous with Thauera and Azoarcus being predominant, and the nirK and sox genes were highly expressed. The study verified the importance of influent loading to regulate S0 recovery, which could be achieved as Thauera and Sulfurimonas dominated. An influent loading that was too low or too high gave rise to insufficient oxidation or over-oxidation of the sulfide and low S0 recovery performance.


Asunto(s)
Bacterias/genética , Bacterias/metabolismo , Reactores Biológicos , Contaminantes Ambientales/aislamiento & purificación , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/microbiología , Azufre/aislamiento & purificación , Acetatos/metabolismo , Anaerobiosis , Azoarcus/química , Azoarcus/genética , Azoarcus/metabolismo , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Nitratos/metabolismo , Oxidación-Reducción , Factores de Transcripción SOX/genética , Sulfuros/metabolismo , Thauera/química , Thauera/genética , Thauera/metabolismo
13.
Environ Sci Technol ; 51(1): 291-300, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-27966913

RESUMEN

Haloaromatic antimicrobial triclocarban (3,4,4'-trichlorocarbanilide, TCC) is a refractory contaminant which is frequently detected in various aquatic and sediment environments globally. However, few TCC-degrading communities or pure cultures have been documented, and functional enzymes involved in TCC biodegradation hitherto have not yet been characterized. In this study, a bacterial strain, Ochrobactrum sp. TCC-2, capable of degrading TCC under both aerobic and anaerobic conditions was isolated from a sediment sample. A novel amidase gene (tccA), responsible for the hydrolysis of the two amide bonds of TCC and its dehalogenated congeners 4,4'-dichlorocarbanilide (DCC) and carbanilide (NCC) to more biodegradable chloroaniline or aniline products, was cloned and characterized. TccA shares low amino acid sequence identity (27 to 38%) with other biochemically characterized amidases and contains the conserved catalytic triad (Ser-Ser-Lys) of the amidase signature enzyme family. TccA was stable over a pH range of 5.0 to 10.0 and at temperatures lower than 60 °C, and it was constitutively expressed in strain TCC-2. In contrast to the halogenated TCC and DCC, the nonchlorinated NCC was the preferred substrate for TccA. TccA also had hydrolysis activity to a broad spectrum of amide bonds in herbicides, insecticides, and chemical intermediates. The constitutive expression and broad substrate spectrum of TccA suggested strain TCC-2 may be potentially useful for bioremediation applications.


Asunto(s)
Biotransformación , Ochrobactrum/metabolismo , Amidohidrolasas/metabolismo , Biodegradación Ambiental , Hidrólisis
14.
J Environ Sci (China) ; 42: 227-235, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27090715

RESUMEN

The colloidal properties of biogenic elemental sulfur (S(0)) cause solid-liquid separation problems, such as poor settling and membrane fouling. In this study, the separation of S(0) from bulk liquids was performed using flocculation. Polyaluminum chloride (PAC), polyacrylamide (PAM) and microbial flocculant (MBF) were compared to investigate their abilities to flocculate S(0) produced during the treatment of sulfate-containing wastewater. A novel approach with response surface methodology (RSM) was employed to evaluate the effects and interactions of flocculant dose, pH and stirring intensity, on the treatment efficiency in terms of the S(0) flocculation and the supernatant turbidity removal. The dose optimization results indicated that the S(0) flocculation efficiency decreased in the following order PAC>MBF>PAM. Optimum S(0) flocculation conditions were observed at pH4.73, a stirring speed of 129 r/min and a flocculant dose of 2.42 mg PAC/mgS. During optimum flocculation conditions, the S(0) flocculation rate reached 97.53%. Confirmation experiments demonstrated that employing PAC for S(0) flocculation is feasible and RSM is an efficient approach for optimizing the process of S(0) flocculation. The results provide basic parameters and conditions for recovering sulfur during the treatment of sulfate-laden wastewaters.


Asunto(s)
Azufre/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Resinas Acrílicas/química , Hidróxido de Aluminio/química , Floculación , Residuos Industriales , Azufre/química , Contaminantes Químicos del Agua/química
15.
Bioresour Technol ; 200: 1019-23, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26497112

RESUMEN

In this study, two lab-scale UASB reactors were established to testify S(0) recovery efficiency, and one of which (M-UASB) was improved from the previous T-UASB by shortening reactor height once S(2-) over oxidation was observed. After the height was shortened from 60 to 30cm, S(0) recovery rate was improved from 7.4% to 78.8%, and while, complete removal of acetate, nitrate and S(2-) was simultaneously maintained. Meanwhile, bacterial community distribution was homogenous throughout the reactor, with denitrifying sulfide oxidization bacteria predominant, such as Thauera and Azoarcus spp., indicating the optimized condition for S(0) recovery. The effective control of working height/volume in reactors plays important roles for the efficient regulation of S(0) recovery during DSR process.


Asunto(s)
Reactores Biológicos/microbiología , Aguas del Alcantarillado , Sulfuros/aislamiento & purificación , Azufre/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Acetatos/aislamiento & purificación , Acetatos/metabolismo , Azoarcus/genética , Azoarcus/metabolismo , Bacterias/genética , Bacterias/metabolismo , Carbono/aislamiento & purificación , Desnitrificación , Diseño de Equipo , Consorcios Microbianos/genética , Consorcios Microbianos/fisiología , Nitratos/aislamiento & purificación , Nitratos/metabolismo , Oxidación-Reducción , Aguas del Alcantarillado/microbiología , Sulfatos/metabolismo , Sulfuros/química , Thauera/genética , Thauera/metabolismo , Eliminación de Residuos Líquidos/instrumentación
16.
Bioresour Technol ; 197: 227-34, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26340031

RESUMEN

Influence of acetate-C/NO3(-)-N/S(2-) ratio to the functional microbial community during the denitrifying sulfide removal process is poorly understood. Here, phylogenetic and functional bacterial community for elemental sulfur (S(0)) recovery and nitrate (NO3(-)) removal were investigated with the switched S(2-)/NO3(-) molar ratio ranged from 5/2 to 5/9. Optimized S(2-)/NO3(-) ratio was evaluated as 5/6, with the bacterial genera predominated with Thauera, Enterobacter, Thiobacillus and Stappia, and the sqr gene highly expressed. However, insufficient or high loading of acetate and NO3(-) resulted in the low S(0) recovery, and also significantly modified the bacterial community and genetic activity. With S(2-)/NO3(-) ratio of 5/2, autotrophic S(2-) oxidization genera were dominated and NO3(-) reduction activity was low, confirmed by the low expressed nirK gene. In contrast, S(2-)/NO3(-) ratio switched to 5/8 and 5/9 introduced diverse heterotrophic nitrate reduction and S(0) over oxidization genera in accompanied with the highly expressed nirK and sox genes.


Asunto(s)
Bacterias/metabolismo , Reactores Biológicos/microbiología , Nitratos/metabolismo , Sulfuros/metabolismo , Procesos Autotróficos , Bacterias/clasificación , Desnitrificación/fisiología , Procesos Heterotróficos , Nitratos/química , Óxidos de Nitrógeno , Sulfuros/química , Azufre/química
17.
Bioresour Technol ; 192: 478-85, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26080105

RESUMEN

Simultaneous removal of COD, SO4(2-) and NO3(-) and recovery of elemental sulfur (S(0)) were evaluated in a four-compartment anaerobic baffled reactor (ABR) with separated functional units of sulfate reduction (SR) and denitrifying sulfide removal (DSR). Optimal SO4(2-)-S/NO3(-)-N ratio was evaluated as 5:5, with a substantial improvement of S(0) recovery maintained at 79.1%, one of the highest level ever reported; meanwhile, removal rates of COD, SO4(2-) and NO3(-) were approached at 71.9%, 92.9% and 98.6%, respectively. Nitrate served as a key factor to control the shift of SR and DSR related populations, with the possible involvement of Thauera sp. during SR and Sulfurovum sp. or Acidiferrobacter sp. during DSR, respectively. DsrB and aprA genes were the most abundant during SR and DSR processes, respectively. Cylindrical-type ABR with the improved elemental sulfur recovery was recommended to deal with sulfate and nitrate-laden wastewater under the optimized SO4(2-)/NO3(-) ratio.


Asunto(s)
Bacterias Anaerobias/metabolismo , Reactores Biológicos/microbiología , Nitratos/metabolismo , Sulfatos/metabolismo , Azufre/aislamiento & purificación , Bacterias Anaerobias/clasificación , Biodegradación Ambiental , Diseño de Equipo , Análisis de Falla de Equipo , Oxidación-Reducción , Azufre/metabolismo , Aguas Residuales/microbiología , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/instrumentación
18.
Water Sci Technol ; 71(5): 709-16, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25768217

RESUMEN

An integrated reactor system was developed for the simultaneous removal of carbon, sulfur and nitrogen from sulfate-laden wastewater and for elemental sulfur (S°) reclamation. The system mainly consisted of an expanded granular sludge bed (EGSB) for sulfate reduction and organic carbon removal (SR-CR), an EGSB for denitrifying sulfide removal (DSR), a biological aerated filter for nitrification and a sedimentation tank for sulfur reclamation. This work investigated the influence of chemical oxygen demand (COD)/sulfate ratios on the performance of the system. Influent sulfate and ammonium were fixed to the level of 600 mg SO(4)(2-) L⁻¹ and 120 mg NH(4)(+) L⁻¹, respectively. Lactate was introduced to generate COD/SO(4)(2-) = 0.5:1, 1:1, 1.5:1, 2:1, 3:1, 3.5:1 and 4:1. The experimental results indicated that sulfate could be efficiently reduced in the SR-CR unit when the COD/SO(4)(2-) ratio was between 1:1 and 3:1, and sulfate reduction was inhibited by the growth of methanogenic bacteria when the COD/SO(4)(2-) ratio was between 3.5:1 and 4:1. Meanwhile, the Org-C/S²â»/NO(3)(-) ratios affected the S(0) reclamation efficiency in the DSR unit. When the influent COD/SO(4)(2-) ratio was between 1:1 and 3:1, appropriate Org-C/S²â»/NO(3)(-) ratios could be achieved to obtain a maximum S° recovery in the DSR unit. For the microbial community of the SR-CR unit at different COD/SO(4)(2-) ratios, 16S rRNA gene-based high throughput Illumina MiSeq sequencing was used to analyze the diversity and potential function of the dominant species.


Asunto(s)
Análisis de la Demanda Biológica de Oxígeno , Reactores Biológicos , Aguas del Alcantarillado/microbiología , Sulfatos , Eliminación de Residuos Líquidos/métodos , Bacterias/genética , Bacterias/crecimiento & desarrollo , Reactores Biológicos/microbiología , Carbono/aislamiento & purificación , Diseño de Equipo , Consorcios Microbianos/genética , Nitrógeno/aislamiento & purificación , ARN Ribosómico 16S , Sulfatos/metabolismo , Sulfuros/metabolismo , Azufre/aislamiento & purificación , Eliminación de Residuos Líquidos/instrumentación , Aguas Residuales/química
19.
J Hazard Mater ; 269: 56-67, 2014 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-24373982

RESUMEN

In this paper, we proposed an integrated reactor system for simultaneous removal of COD, sulfate and ammonium (integrated C-S-N removal system) and investigated the key parameters of the system for a high level of elemental sulfur (S(0)) production. The system consisted of 4 main units: sulfate reduction and organic carbon removal (SR-CR), autotrophic and heterotrophic denitrifying sulfide removal (A&H-DSR), sulfur reclamation (SR), and aerated filter for aerobic nitrification (AN). In the system, the effects of key operational parameters on production of elemental sulfur were investigated, including hydraulic retention time (HRT) of each unit, sulfide/nitrate (S(2-)-S/NO3(-)-N) ratios, reflux ratios between the A&H-DSR and AN units, and loading rates of chemical oxygen demand (COD), sulfate and ammonium. Physico-chemical characteristics of biosulfur were studied for acquiring efficient S(0) recovery. The experiments successfully explored the optimum parameters for each unit and demonstrated 98% COD, 98% sulfate and 78% nitrogen removal efficiency. The optimum HRTs for SR-CR, A&H-DSR and AN were 12h, 3h and 3h, respectively. The reflux ratio of 3 could provide adequate S(2-)-S/NO3(-)-N ratio (approximately 1:1) to the A&H-DSR unit for obtaining maximum sulfur production. In this system, the maximum production of S(0) reached 90%, but only 60% S(0) was reclaimed from effluent. The S(0) that adhered to the outer layer of granules was deposited in the bottom of the A&H-DSR unit. Finally, the microbial community structure of the corresponding unit at different operational stage were analyzed by 16S rRNA gene based high throughput Illumina MiSeq sequencing and the potential function of dominant species were discussed.


Asunto(s)
Compuestos de Amonio/aislamiento & purificación , Reactores Biológicos , Oxígeno/química , Sulfatos/aislamiento & purificación , Bacterias Reductoras del Azufre/metabolismo , Azufre/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Algoritmos , Bacterias/química , Bacterias/metabolismo , Carbono/química , Cromatografía por Intercambio Iónico , Nitrógeno/química , Azufre/química , Aguas Residuales/química , Microbiología del Agua
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