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1.
Health Educ Res ; 35(6): 512-523, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-32879948

RESUMEN

Georgia experiences higher human papillomavirus (HPV)-associated cancer burden and lower HPV vaccine uptake compared with national estimates. Using the P3 model that concomitantly assesses practice-, provider- and patient-level factors influencing health behaviors, we examined facilitators of and barriers to HPV vaccine promotion and uptake in Georgia. In 2018, we conducted six focus groups with 55 providers. Questions focused on multilevel facilitators of and barriers to HPV vaccine promotion and uptake. Our analysis was guided by the P3 model and a deductive coding approach. We found that practice-level influences included organizational priorities of vaccinations, appointment scheduling, immunization registries/records, vaccine availability and coordination with community resources. Provider-level influences included time constraints, role, vaccine knowledge, self-efficacy to discuss HPV vaccine and vaccine confidence. Patient-level influences included trust, experiences with vaccine-preventable diseases, perceived high costs, perceived side effects and concerns with sexual activity. Findings suggest that interventions include incentives to boost vaccine rates and incorporate appointment scheduling technology. An emphasis should be placed on the use of immunization registries, improving across-practice information exchange, and providing education for providers on HPV vaccine. Patient-provider communication and trust emerge as intervention targets. Providers should be trained in addressing patient concerns related to costs, side effects and sexual activity.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Georgia , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud , Humanos , Infecciones por Papillomavirus/prevención & control , Vacunación
3.
Chemosphere ; 304: 135178, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35660057

RESUMEN

In this study, the response of antibiotic resistance genes (ARGs), mobile gene elements (intI1), and human bacterial pathogens (HBPs) to addition of manure biochar (1-10 g/L) was studied in anaerobic digestion (AD) at 20-55 °C for treating dairy manure. Twelve ARGs comprising five tetracycline resistance genes, two sulfonamide resistance genes, two macrolide resistance genes, three ß-lactam antibiotic resistance genes, and intI1 were analyzed by quantitative PCR. High-throughput sequencing data were matched against a database of putative 538 HBPs. Significant removal of ARGs (except for tetO and ermB) and intI1 was observed in all the samples. Manure biochar resulted in significant removal of ARGs and HBPs; however, negative effects were also observed in some conditions. This is the first study to provide to explore the fates of ARGs and HBPs by adding manure biochar to AD.


Asunto(s)
Antibacterianos , Estiércol , Anaerobiosis , Antibacterianos/farmacología , Bacterias/genética , Carbón Orgánico , Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Humanos , Macrólidos , Estiércol/microbiología
4.
Bioresour Technol ; 351: 127025, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35307521

RESUMEN

This study evaluated the relationship between pyrolysis temperature (300-900 ℃), characteristics of swine manure (SM)-derived biochar (BC), and its adsorption of levofloxacin (LEV). The surface structure and chemistry of SM-derived BCs were characterized using Brunauer-Emmett-Teller analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. According to the characteristic analysis, the surface area and graphitization degree of SM-derived BC increased as temperature rose. The highest adsorption capacity was achieved by BC-900 (158 mg/g); this level was higher than that achieved in previous studies and comparable to that of commercial activated carbons. Characterization and adsorption experiments indicated that pore-filling, π-π stacking interaction, π-π electron donor-acceptor, H-bonding, and hydrophobic interactions each played a critical role in the adsorption of LEV on SM-derived BC. Collectively, this study confirms the potential utility of SM-derived BC for the removal of antibiotics.


Asunto(s)
Levofloxacino , Contaminantes Químicos del Agua , Adsorción , Animales , Carbón Orgánico/química , Cinética , Levofloxacino/análisis , Estiércol , Espectroscopía Infrarroja por Transformada de Fourier , Porcinos , Contaminantes Químicos del Agua/química
5.
ACS Omega ; 6(26): 16934-16942, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34250352

RESUMEN

Mechanical refining (MR) is a cost-effective pretreatment in biochemical conversion processes that is employed to overcome biomass recalcitrance. This work studied the effects of MR on biogas and methane produced by the anaerobic digestion (AD) of dairy manure. The cumulative gas volume and yield from the AD of manure refined at 6k revolutions increased by 33.7 and 7.7% for methane and by 32.0 and 6.4% for biogas, respectively, compared to the unrefined manure. This enhancement was reached by increasing manure solubilization, reducing particle size, and achieving external fibrillation and internal delamination of fibers in manure. However, the highly refined manure (subjected to 60k revolutions) exhibited methane and biogas yields that were reduced by 9.5 and 1.5%, respectively. This decrease was observed because the pore structure was ruptured, and finely ground manure particles were aggregated together at high revolutions (60k), thereby inhibiting the release of organic matter from the manure. Therefore, this study indicates that the MR for pretreatment of dairy manure could have great potential for significantly enhancing AD of dairy manure. Further studies will include optimization of conditions of mechanical refining (i.e., mechanical intensity, process time), a continuous AD of dairy manure pretreated by the MR, and scale-up with cost evaluation.

6.
Bioresour Technol ; 329: 124905, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33676351

RESUMEN

Parameters of temperature-phased anaerobic digestion (TPAD) were varied to study their effects on hydrolysis, biomethane potential (BMP), and microbial diversity of microalgae biodegradation. Anaerobic pretreatments at 85 °C demonstrated the release of soluble carbohydrate and protein molecules under low microbial metabolic activity. However, at 55 °C, anaerobic pretreatments showed superior performance in methane yield, nutrient release, and volatile fatty acids (VFAs) production due to dominant Clostridium. Furthermore, the highest destruction of volatile solids (VS) was observed during aerobic pretreatments at 55 °C under the influence of various quantities of these genera - Luteimonas, Symbiobacterium, Soehngenia, Thermobacillus, and Ureibacillus. Statistical analysis revealed that hydrolysis and BMP were not correlated. However, soluble nitrogen and phosphorous showed strong correlation with methane (r = 0.623 and 0.948, respectively) under thermo-anaerobic pretreatment, while VS removal and concentrations of acetic and butyric acids and lipids were positively correlated with each other under thermo-aerobic pretreatment.


Asunto(s)
Microalgas , Microbiota , Anaerobiosis , Hidrólisis , Metano
7.
Bioresour Technol ; 312: 123577, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32531733

RESUMEN

This study focus on the fate of ARGs in the full-scale AD of food wastewater (FWW). Residue was collected from two different full-scale thermophilic AD treating FWW. Ten selected ARGs, including tetracycline resistance genes (tetM, tetX, tetQ, tetH and tetG), sulfonamide resistance genes (sul1 and sul2), quinolone resistance genes (qnrD) and macrolide resistance genes (ermB and ermC), were amplified using quantitative polymerase chain reaction (qPCR). Furthermore, the class 1 integron-integrase gene (intI1) was selected as a representative mobile gene element. Remarkable reduction in the ARGs and intI1 was observed in two-stage (acidogenic-methanogenic) AD, particularly, tetG, tetH, tetM, tetQ, tetX and intI1 not detected. Additionally, significant positive correlation (p < 0.01) between ARGs and intI1 suggested a strong likelihood of horizontal gene transfer (HGT). Furthermore, stepwise multiple linear regression analysis revealed significant factors related to the fate of individual ARGs and intI1 during AD.


Asunto(s)
Antibacterianos , Aguas Residuales , Anaerobiosis , Farmacorresistencia Bacteriana , Genes Bacterianos , Macrólidos
8.
Transl Behav Med ; 10(6): 1330-1341, 2020 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-33421082

RESUMEN

Little is known about the prevalence and correlates of food insecurity among immigrants and refugees. Acculturation and social connectedness may influence food insecurity (lack of access at all times to enough food for an active, healthy life) by affecting a person's ability to access and use governmental and charitable food assistance programs, as well as other community-based or informal food-related resources. We explored associations of acculturation and social connectedness with food insecurity among diverse immigrants and refugees living in metropolitan Atlanta, a major destination for these populations in recent years. From 2017 to 2018, we surveyed 162 adults attending health fairs or programs hosted by two community-based organizations serving immigrants and refugees. Food insecurity within the past year was assessed using the American Academy of Pediatrics' two-item questionnaire. Acculturation indicators included heritage culture and American acculturation scores (Vancouver Acculturation Index), English fluency, heritage language fluency, and percentage of lifetime in the USA. Social connectedness was operationalized using measures of religious attendance and social isolation. We conducted a multivariable logistic regression controlling for age, sex, education, household income, employment status, and household size. In the sample, 51.9% identified as Vietnamese, 16.0% Hispanic, 15.4% Burmese, 14.8% Bhutanese or Nepali, and 1.8% other. The average age was 39.10 (standard deviation [SD] =13.83), 34.0% were male, 73.8% had below a Bachelor's degree, and 49.7% were unemployed. Average scores for American acculturation (mean [M] = 3.26, SD = 1.05, range 1-5) were lower than heritage acculturation (M = 4.34, SD = 0.68, range 1-5). Additionally, 43.4% were fluent in English. Average percentage of life in the USA was 40.59% (SD = 33.48). Regarding social connectedness, 55.9% regularly attended religious services. Average social isolation scores were 3.93 (SD = 1.34, range 3-9). Overall, past-year food insecurity was reported by 17.3% (34.6% in Hispanics, 24.0% in Burmese, 13.1% in Vietnamese, and 8.3% in Bhutanese or Nepali). In adjusted models, food insecurity was associated with English fluency (adjusted odds ratio [aOR] = 0.36, p = .03) and social isolation (aOR = 2.29, p < .001) but not other measures of acculturation or religious attendance. Limited English proficiency may make it more difficult to navigate or use governmental and charitable food assistance programs. Social isolation may hinder individuals from obtaining information about food assistance programs, receiving aid for services navigation, and sharing or borrowing food from family, friends, and neighbors. Interventions should seek to improve access to English language and literacy services, enhance the linguistic and cultural competency of service providers, and build social connectedness among immigrants and refugees.


Asunto(s)
Emigrantes e Inmigrantes , Refugiados , Aculturación , Adulto , Bután , Niño , Inseguridad Alimentaria , Abastecimiento de Alimentos , Humanos , Masculino , Estados Unidos
9.
Bioresour Technol ; 284: 437-447, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30981196

RESUMEN

For the first time the present study investigated the production, characterization and application of engineered biochar derived from alfalfa hays for removal of tetracycline (TC) in water. The NaOH activation of alfalfa-derived raw biochar (BCR) made significant increase in surface area (796.50 m2/g) and pore volume (0.087 cm3/g). The NaOH-activated BC (BCA) showed much higher adsorption capacity for TC (Qm = 302.37 mg/g) than BCR, but comparable to the commercial activated carbon (Calgon F400). The detailed analyses of the kinetic and isotherm studies suggested the strong chemisorptive interactions between TC and BCA via multiple mechanisms. In addition, intraparticle diffusion was considered as the major limitation for the adsorption of TC onto BCA. Furthermore, the fixed bed experiments revealed that BCA could be a promising adsorbent for treating large volume of TC-contaminated water in columns.


Asunto(s)
Antibacterianos/química , Carbón Orgánico/química , Tetraciclina/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Adsorción , Agricultura , Cinética , Purificación del Agua
10.
Bioresour Technol ; 274: 162-172, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30504099

RESUMEN

The biochars derived from alfalfa (AF) and bermudagrass (BG), the abundant grass hays to cows, were prepared, characterized and used for removal of tetracycline (TC) in water. The alfalfa-derived biochar (AF-BC) has exhibited outstanding TC adsorption capacity (372 mg/g), which was about 8-fold higher than that of bermudagrass-derived biochar (BG-BC). In addition, the TC adsorption capacity of AF-BC was comparable with those of the commercial activated carbons under the same conditions. The surface structure, chemistry and high ash contents of AF-BC suggested the hydrogen bonding, electrostatic interactions and surface complexation between AF-BC and TC. Furthermore, hydroxyapatite (HAP; Ca5(PO4)3OH) and calcite (CaCO3) on the surface of AF-BC may also contribute to adsorption of TC via surface complexation, hydrogen bonding and electrostatic interactions. The alkaline desorption-driven regeneration of TC-spent AF-BC led to effective adsorption-desorption for multiple cycles, which indicated AF-BC could be a cost-effective adsorbent for TC in water and wastewater.


Asunto(s)
Carbón Orgánico/química , Medicago sativa/química , Tetraciclinas/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Adsorción , Animales , Bovinos , Femenino , Tetraciclinas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua
11.
Sci Total Environ ; 687: 87-95, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31203011

RESUMEN

Effects of two different start-up methods were compared during conversion from mesophilic to thermophilic anaerobic digestion of sewage sludge. During the batch operation, a transient increase in both total bacterial concentration and relative abundance of thermophilic bacteria in R1 (a one-step increase method) resulted in 34% higher volatile solids (VS) removal efficiency by R1 compared to R2 (a step-wise increase method). Meanwhile, higher total archaeal concentration and increased relative abundance of thermophilic archaea in R2 were attributed to 65% higher methane production by R2 compared to R1. The same trends for VS removal and methane production were observed during the subsequent continuous mode, although the microbial composition of the two reactors became similar. These findings may prove helpful for determining the preferred start-up method for thermophilic anaerobic digestion: a one-step method can be proposed for higher VS removal efficiency, or a step-wise method can be selected for enhanced methane production.


Asunto(s)
Microbiota , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Anaerobiosis , Archaea , Bacterias , Bacterias Anaerobias
12.
Bioresour Technol ; 250: 927-931, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29198415

RESUMEN

Effects of dairy manure-derived biochar (M-BC) on methane production in anaerobic digestion (AD) of dry dairy manure were investigated with three different concentrations of biochar (0, 1 and 10 g/L) and temperatures (psychrophilic, 20 °C; mesophilic, 35 °C; thermophilic, 55 °C). Compared with the AD without any biochar, the cumulative methane and yield in the AD with 10 g/L biochar were increased to 27.65% and 26.47% in psychrophilic, 32.21% and 24.90% in mesophilic and 35.71% and 24.69% in thermophilic digestions. The addition of M-BC shortened the lag phases of AD at all temperatures in the study while it lowered the concentration of total VFAs and propionic acid. It was suggested that the high nutrients and alkalinity potential of M-BC (i.e. 9.1% Ca, 3.6% Mg, 1.3% N, 0.14% P) would play significant roles in enhancing methane production and shortening lag phases from the AD of dairy manure.


Asunto(s)
Carbón Orgánico , Estiércol , Anaerobiosis , Reactores Biológicos , Digestión , Metano
13.
Bioresour Technol ; 259: 24-31, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29536870

RESUMEN

The objective of this study was to evaluate the adsorption of tetracycline (TC) on the Pinus taeda-derived activated biochar (BC). After NaOH activation, the well-developed porous surface structure was observed with a significantly increase in surface area (959.9 m2/g). The kinetic and isotherm studies indicated that hydrogen bonding and π-π interaction on the heterogeneous surface would be the possible mechanisms, while intra-particle diffusion was considered as the major limitation for the adsorption of TC on the activated BC. The maximum adsorption capacity of the activated BC (274.8 mg TC/g BC) was higher than those of various activated BCs from the previous studies while it was similar to those of commercial activated carbons. It indicated that the activated BC had the high potential for TC removal in water.


Asunto(s)
Carbón Orgánico , Pinus taeda , Tetraciclina , Adsorción , Cinética , Contaminantes Químicos del Agua
14.
Bioresour Technol ; 267: 303-310, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30029175

RESUMEN

Response of antibiotic resistance genes (ARGs) and heavy metal resistance genes (HMRGs) to two different temperature sequences (i.e., mesophilic-thermophilic and thermophilic-mesophilic) were investigated. Higher removal of total ARGs (twenty-one targeted subtypes) and HMRGs (three targeted subtypes) was achieved by the mesophilic-thermophilic sequence than by the thermophilic-mesophilic sequence. The sequence of mesophilic-thermophilic showed the highest removal of total ARGs, but the sequence of thermophilic-mesophilic proved more suitable for removal of class 1 integrons (intI1). Correlation analysis indicated that intI1 correlated significantly with tetG, tetQ, tetX, sul2, aac(6')-lb-cr, blaTEM, ermB and floR. High-throughput sequencing revealed that the mesophilic-thermophilic sequence TPAD removed more human bacterial pathogens (HBPs) than did the thermophilic-mesophilic sequence. Also, significantly positive correlation was observed between ARGs and HBPs. For instance, Mycoplasma pneumonia showed significantly positive correlation with several ARGs including tetE, tetQ, tetX, tetZ, sul1, sul2, aac(6')-lb-cr and floR.


Asunto(s)
Antibacterianos/farmacología , Bacterias/aislamiento & purificación , Farmacorresistencia Microbiana , Metales Pesados , Genes Bacterianos , Aguas del Alcantarillado , Temperatura
15.
Bioresour Technol ; 249: 635-643, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29091848

RESUMEN

This study examines the fate of twenty-three representative antibiotic resistance genes (ARGs) encoding tetracyclines, sulfonamides, quinolones, ß-lactam antibiotics, macrolides, florfenicol and multidrug resistance during thermophilic aerobic digestion (TAD) of sewage sludge. The bacterial community, class 1 integrons (intI1) and four metal resistance genes (MRGs) were also quantified to determine the key drivers of changes in ARGs during TAD. At the end of digestion, significant decreases in the quantities of ARGs, MRGs and intI1 as well as 16S rRNA genes were observed. Partial redundancy analysis (RDA) showed that shifts in temperature were the key factors affecting a decrease in ARGs. Shifts in temperature led to decreased amounts of ARGs by reducing resistome and bacterial diversity, rather than by lowering horizontal transfer potential via intI1 or co-resistance via MRGs.


Asunto(s)
Antibacterianos , Metales , Aguas del Alcantarillado , Farmacorresistencia Microbiana , Genes Bacterianos , ARN Ribosómico 16S
16.
Environ Pollut ; 233: 1049-1057, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29031406

RESUMEN

The wide use of antibiotics in aquaculture for prophylactic and therapeutic purposes can potentially lead to the prevalence of antibiotic resistance genes (ARGs). This study reports for the first time the profile of ARGs from effluents of coastal aquaculture located in South Jeolla province and Jeju Island, South Korea. Using quantitative PCR (qPCR), twenty-two ARGs encoding tetracycline resistance (tetA, tetB, tetD, tetE, tetG, tetH, tetM, tetQ, tetX, tetZ, tetBP), sulfonamide resistance (sul1, sul2), quinolone resistance (qnrD, qnrS, aac(6')-Ib-cr), ß-lactams resistance (blaTEM, blaCTX, blaSHV), macrolide resistance (ermC), florfenicol resistance (floR) and multidrug resistance (oqxA) and a class 1 integrons-integrase gene (intI1) were quantified. In addition, Illumina Miseq sequencing was applied to investigate microbial community differences across fish farm effluents. Results from qPCR showed that the total number of detected ARGs ranged from 4.24 × 10-3 to 1.46 × 10-2 copies/16S rRNA gene. Among them, tetB and tetD were predominant, accounting for 74.8%-98.0% of the total ARGs. Furthermore, intI1 gene showed positive correlation with tetB, tetD, tetE, tetH, tetX, tetZ tetQ and sul1. Microbial community analysis revealed potential host bacteria for ARGs and intI1. Two genera, Vibrio and Marinomonas belonging to Gammaproteobacteria, showed significant correlation with tetB and tetD, the most dominant ARGs in all samples. Also, operational taxonomic units (OTUs)-based network analysis revealed that ten OTUs, classified into the phyla Proteobacteria, Cyanobacteria/Chloroplast, Bacteroidetes, Verrucomicrobia and an unclassified phylum, were potential hosts of tetracycline resistance genes (i.e., tetA, tetG, tetH, tetM, tetQ and tetZ). Further systematic monitoring of ARGs is warranted for risk assessment and management of antibacterial resistance from fish farm effluents.


Asunto(s)
Acuicultura , Farmacorresistencia Microbiana/genética , Monitoreo del Ambiente , Animales , Bacterias/efectos de los fármacos , Genes Bacterianos/efectos de los fármacos , Integrones , Prevalencia , ARN Ribosómico 16S/genética , República de Corea , Microbiología del Agua , Contaminación del Agua/análisis , Contaminación del Agua/estadística & datos numéricos
17.
Bioresour Technol ; 244(Pt 1): 433-444, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28797965

RESUMEN

Anaerobic digestion (AD) of chemically enhanced primary treatment (CEPT) sludge and non-CEPT (conventional sedimentation) sludge were comparatively operated under mesophilic and thermophilic conditions. The highest methane yield (692.46±0.46mL CH4/g VSremoved in CEPT sludge) was observed in mesophilic AD of CEPT sludge. Meanwhile, thermophilic conditions were more favorable for the removal of total antibiotic resistance genes (ARGs). In this study, no measurable difference in the fates and removal of ARGs and class 1 integrin-integrase gene (intI1) was observed between treated non-CEPT and CEPT sludge. However, redundancy analysis indicated that shifts in bacterial community were primarily accountable for the variations in ARGs and intI1. Network analysis further revealed potential host bacteria for ARGs and intI1.


Asunto(s)
Antibacterianos , Farmacorresistencia Microbiana , Aguas del Alcantarillado , Anaerobiosis , Bacterias/genética
18.
Sci Total Environ ; 605-606: 906-914, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28686994

RESUMEN

In this study, quantitative and qualitative changes in antibiotics resistance genes (ARGs) were investigated in two municipal wastewater treatment plants (WWTPs) treating pretreated livestock or industrial wastewater as well as municipal sewage. Total eight ARGs (tetX, tetM, tetA, sul1, sul2, ermB, qnrD, and blaTEM) were quantified, and their relative abundance was assessed by ARGs copies/16S rRNA gene copies. The fate of ARGs was observed to be different between two WWTPs: sul, qnrD, and blaTEM were proliferated during the treatment processes only in the WWTP1 which received pretreated livestock wastewater. Furthermore, dynamic shifts in patterns of ARGs occurrence were observed during biological, secondary sedimentation and coagulation processes. During biological treatment in both WWTPs, relative abundance of tet and ermB changed: tet increased significantly by 211.6-357.6%, while ermB decreased by 70.4-92.0%. Little variation was observed in sul, qnrD and blaTEM. Subsequently, the relative abundance of tet decreased during the secondary sedimentation and coagulation in both WWTPs: tet decreased by 56.0-86.3% during sedimentation and by 48.2-75.7% during coagulation, respectively. During the final treatment, different responses of antibiotic resistance bacteria (ARB) and ARGs to ultraviolet (UV) disinfection were found: removal efficiencies of ARB were observed in the range of 34-75%, while obvious reduction in ARGs was not observed at the UV dose of 27mJ/cm2. Although ARGs underwent various treatment processes, considerable levels of ARGs remained at discharge amounting to 4.2×1018 copies/day from WWTP1 and 5.4×1016 copies/day from WWTP2, respectively.


Asunto(s)
Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Eliminación de Residuos Líquidos , Aguas Residuales/análisis , Antibacterianos , Bacterias/efectos de los fármacos , ARN Ribosómico 16S/genética , Aguas del Alcantarillado
19.
Sci Total Environ ; 579: 1692-1698, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27923578

RESUMEN

In this research, the distribution of antibiotic resistance genes (ARGs) was characterized in representative organic solid waste (OSW) in Korea: food waste-recycling wastewater (FRW), manure, and sewage sludge. The amounts of total ARG (gene copies/16S rRNA gene copies) was greatest in manure followed by sewage sludge and FRW. Interestingly, there were significantly different patterns in the diversity and mechanisms of ARGs. For example, a significant proportion of ARGs were tetracycline resistant genes in all the OSW (40.4-78.2%). ß-lactam antibiotics resistant genes were higher in the FRW samples than in other types of OSW but sulfonamides resistant genes represented the greatest proportion in sludge. Regarding the characteristics of antibiotic resistance mechanisms, there was a relatively higher proportion of the ribosomal protection mechanism to tetracycline observed in the FRW and manure samples. However, tetracycline resistant genes with direct interaction were relatively higher in the sewage sludge samples. sul1 was the dominant subtype in all the OSW types and detection of ermB was observed although there was no ermC detected in sewage sludge. There were significant correlations between the occurrences of ARG subtypes: tetB and tetG in all OSW (P<0.01); tetE and tetQ only in sludge (P<0.01). The Class 1 integron-integrase gene (intI1) was significantly correlated with total ARGs only in manure and sludge (P<0.05), revealing potential horizontal gene transfer in these OSW.


Asunto(s)
Farmacorresistencia Microbiana/genética , Monitoreo del Ambiente , Industria de Alimentos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/microbiología , Residuos Industriales , República de Corea , Aguas del Alcantarillado/microbiología
20.
Water Res ; 99: 140-148, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27155112

RESUMEN

In recent years, anaerobic co-digestion (AcoD) has been widely used to improve reactor performance, especially methane production. In this study, we applied two different operating temperatures (thermophilic and mesophilic) and gradually increased the load of food wastewater (FWW) to investigate the bacterial communities during the AcoD of waste activated sludge (WAS) and FWW. As the load of FWW was increased, methane production rate (MPR; L CH4/L d) and methane content (%) in both Thermophilic AcoD (TAcoD) and Mesophilic AcoD (MAcoD) increased significantly; the highest MPR and methane content in TAcoD (1.423 L CH4/L d and 68.24%) and MAcoD (1.233 L CH4/L d and 65.21%) were observed when the FWW mixing ratio was 75%. However, MPR and methane yield in both reactors decreased markedly and methane production in TAcoD ceased completely when only FWW was fed into the reactor, resulting from acidification of the reactor caused by accumulation of organic acids. Pyrosequencing analysis revealed a decrease in bacterial diversity in TAcoD and a markedly different composition of bacterial communities between TAcoD and MAcoD with an increase in FWW load. For example, Bacterial members belonging to two genera Petrotoga (assigned to phylum Thermotogae) and Petrimonas (assigned to phylum Bacteroidetes) became dominant in TAcoD and MAcoD with an increase in FWW load, respectively. In addition, quantitative real-time PCR (qPCR) results showed higher bacterial and archaeal populations (expressed as 16S rRNA gene concentration) in TAcoD than MAcoD with an increase in FWW load and showed maximum population when the FWW mixing ratio was 75% in both reactors. Collectively, this study demonstrated the dynamics of key bacterial communities in TAcoD and MAcoD, which were highly affected by the load of FWW.


Asunto(s)
Aguas del Alcantarillado/microbiología , Aguas Residuales , Anaerobiosis , Reactores Biológicos/microbiología , Metano , ARN Ribosómico 16S
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