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1.
Reprod Sci ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977640

RESUMO

Management of cardiovascular disease in pregnancy is important, yet the association between cardiovascular health and infertility is rarely reported. In this study, we aimed to explore the association between Life's Essential 8 (LE8), a novel cardiovascular health (CVH) measure, and infertility, and to investigate potential mediating mechanisms. This study investigated cross-sectional data from the 2013-2018 National Health and Nutrition Examination Survey. LE8 score (ranging from 0 to 100) was calculated as the unweighted average of eight CVH metrics. The association between LE8 and infertility was explored through weighted multiple logistic regression. Restricted cubic splines were used to explore nonlinear correlation. In addition, mediation analysis was conducted to investigate the role of oxidative stress and inflammatory markers systematically. After strict exclusion criteria, 1703 American women aged 18-45 years were included. After full adjustment, the LE8 score showed a negative correlation with infertility [per 1 SD increase, OR = 0.675, 95% CI: 0.553-0.824], with a linear dose-response relationship (non-linear P = 0.122). Similar linear negative correlations were found between health factor scores and infertility, with higher body mass index and glucose scores having a significantly lower risk of infertility. Stratified analyses showed a stronger inversed relationship between LE8 and infertility in younger populations. Moreover, mediation analysis revealed that uric acid concentration and lymphocyte count mediated the effect of LE8 on infertility (P < 0.05). LE8 and its subscale scores were linearly and negatively associated with infertility, which may be mediated in part through uric acid and lymphocyte count. Focusing on weight management and glycemic control can effectively reduce the risk of infertility.

2.
Chemosphere ; 355: 141825, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552802

RESUMO

BACKGROUND: Most research exploring the correlation between volatile organic compounds (VOCs) and hematological parameters have focused on single VOCs. Our study aimed to explore the single and combined effects of VOCs on hematological parameters through three statistical models. METHODS: Data from 4 cycles of the National Health and Nutrition Examination Survey (NHANES) were used in this study. The correlations between single exposure to 16 VOCs and hematological parameters in the general population were assessed by weighted multiple linear regression. Weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models were used to explore the relationship between the combined important VOCs selected by the least absolute shrinkage and selection operator (LASSO) and hematological parameters, as well as the effects of smoking status on them. RESULTS: A total of 4089 adults were included in the study. We found that a variety of VOCs were significantly associated with hematological parameters. Among them, N-acetyl-S-(benzyl)-l-cysteine (BMA) was significantly negatively correlated with white blood cell (WBC), red blood cell (RBC), lymphocyte, and neutrophil counts. N-acetyl-S-(3-hydroxypropyl-1-methyl)-l-cysteine (HPMMA) was significantly positively correlated with WBC, monocyte, lymphocyte, and neutrophil counts. In the WQS analysis, the WQS index of the VOCs mixtures was positively correlated with WBC (ß: 0.031; P < 0.001), monocyte (0.023; P = 0.021), and neutrophil (0.040; P = 0.001) counts, while negatively associated with RBC (-0.013; P < 0.001) counts. The BKMR model revealed that combined exposure to VOCs levels ≥70th percentile was significantly associated with lower RBC counts, and BMA was identified as the dominant contributor. Smoking significantly influenced the relationship between VOCs and hematological parameters. CONCLUSIONS: Our study indicated the effects of single and overall VOCs exposure on hematological parameters and suggested the hematotoxicity as well as pro-inflammatory effects of VOCs, which had strong public health implications for reducing the potential health hazards of VOCs exposure to the hematologic system.


Assuntos
Exposição Ambiental , Compostos Orgânicos Voláteis , Adulto , Humanos , Exposição Ambiental/análise , Inquéritos Nutricionais , Compostos Orgânicos Voláteis/toxicidade , Fumar , Teorema de Bayes , Cisteína
3.
BMC Geriatr ; 23(1): 745, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968629

RESUMO

BACKGROUND: This study was to explore the relationship between chronic constipation, chronic diarrhea, and frailty in older Americans. METHODS: This cross-sectional study selected a total of 4241 community-dwelling individuals aged 60 years and older from the 2005-2010 National Health and Nutrition Examination Survey. Frailty was measured using a 49-item frailty index, and a frailty index > 0.21 was defined as a frail status. Chronic constipation and chronic diarrhea were defined as the "usual or most common type of stool" by the Bristol Stool Form Scale (BSFS) Types 1 and 2 and BSFS Types 6 and 7, respectively. Weighted logistic regression analysis was used to examine the relationship between gut health and frailty status. Restricted cubic spline (RCS) curves were built to assess the association between frailty index and stool frequency. RESULTS: Frailty status was associated with higher odds of constipation in an unadjusted model; however, after further adjusting for confounding variables, the relationship between frailty status and constipation was not statistically significant. We discovered a positive correlation between the frailty status and diarrhea after adjustment for all variables. The frailty index showed a U-shaped relationship with stool frequency, and the frailty index was the smallest at a frequency of 10 stools/week. CONCLUSION: Negative associations were observed between frailty status and chronic constipation and diarrhea among older adults. Older adults who have a bowel movement frequency of about 10 times per week are the least frail. Future studies are warranted to confirm the causal relationship in this association.


Assuntos
Fragilidade , Humanos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Idoso , Inquéritos Nutricionais , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Fragilidade/complicações , Estudos Transversais , Constipação Intestinal/diagnóstico , Constipação Intestinal/epidemiologia , Diarreia/diagnóstico , Diarreia/epidemiologia , Diarreia/etiologia , Idoso Fragilizado
4.
Environ Sci Pollut Res Int ; 30(57): 120930-120944, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37945964

RESUMO

Substrates like sand or gravels and aquatic nutrient concentrations of rivers are highly heterogeneous, influencing the abundance of functional genes in epilithic biofilms where nitrification-denitrification processes take place. To analyze how the relative abundance of nitrifying/denitrifying genes and the associated microbes changes with the physical properties of substrates and aquatic concentrations of nutrients, this paper utilized metagenomics to comprehensively characterize these functional genes (i.e., amoA, hao, and nxrB involved in nitrification, and napA, narG, nirS, norB, and nosZ associated with denitrification) from epilithic biofilms collected along the Shitingjiang River in Southwest China and further obtained the relative abundance of major nitrifiers and denitrifiers. The results show that substrate size most significantly affects the relative abundance of hao and norB by altering the hydrodynamic conditions. In sampling sites with high heterogeneity in substrate size distribution, the relative abundance of most denitrifying genes is also higher. The carbon-nitrogen ratio negatively correlates with the relative abundance of all the nitrifying genes, while ammonium, total inorganic carbon, and total organic carbon concentrations positively affect the relative abundance of amoA and nxrB. As to the relative abundance of nitrifiers and denitrifiers, mainly belonging to phyla Proteobacteria and Actinobacteria, substrate heterogeneity and the aquatic concentrations of nutrients have greater influences than substrate size. Also, the substrate heterogeneity exerted positive influence on functional species of Pseudogemmobacter bohemicus and Paracoccus zhejiangensis. Considering the genes' functions and the dominant species linked to denitrification, nitrous oxide is more likely to occur in rivers with higher heterogeneity and larger substrates.


Assuntos
Desnitrificação , Nitrificação , Bactérias/genética , Biofilmes , Carbono , Nitrogênio , Microbiologia do Solo
5.
Nutr Metab Cardiovasc Dis ; 33(12): 2488-2496, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37798234

RESUMO

BACKGROUND AND AIMS: Little research have focused on the relationship between systemic oxidative stress status and NAFLD and fibrosis. The Oxidative Balance Score (OBS) is employed to evaluate whole-body lifestyle and diet exposures related to oxidative stress, with higher OBS scores implying exposure to more antioxidants. This study aimed to explore whether OBS is correlated with NAFLD and NAFLD-related fibrosis. METHODS AND RESULTS: 12,223 participants from NHANES 2003-2018 were enrolled in this study. NAFLD was defined as USFLI ≥30 and liver fibrosis was determined as FIB-4 ≥ 2.67. OBS was scored by 20 lifestyle and dietary factors. Weighted logistic regression and restricted cubic splines were used to assess the association between OBS and NAFLD and fibrosis. The prevalence of NAFLD was 29.67%. There was a significant negative correlation between OBS, dietary OBS, lifestyle OBS and NAFLD and no correlation with NAFLD-related fibrosis. Compared to the lowest quartile, the adjusted ORs for the highest quartile of OBS, lifestyle OBS, dietary OBS and NAFLD were 0.55(95%CI:0.35,0.85), 0.12(95%CI:0.08,0.16), 0.70(95%CI:0.52,0.94) respectively. In stratified analyses, lifestyle OBS was negatively associated with NAFLD across gender, dietary OBS was only negatively correlated with NAFLD in men, and any OBS was not observed to be relevant to NAFLD-related fibrosis. CONCLUSIONS: OBS was negatively associated with NAFLD, but not with NAFLD-related fibrosis. The findings underline the significance of adhering to an antioxidant lifestyle and diet, which can help prevent NAFLD but seems to be ineffective in preventing fibrosis in individuals with NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Adulto , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Inquéritos Nutricionais , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Oxirredução , Antioxidantes , Estresse Oxidativo
6.
J Transl Med ; 21(1): 622, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710295

RESUMO

BACKGROUND: Biological ageing is tightly linked to cardiovascular disease (CVD). We aimed to investigate the relationship between Life's Essential 8 (LE8), a currently updated measure of cardiovascular health (CVH), and biological ageing. METHODS: This cross-sectional study selected adults ≥ 20 years of age from the 2005-2010 National Health and Nutrition Examination Survey. LE8 scores (range 0-100) were obtained from measurements based on American Heart Association definitions, divided into health behavior and health factor scores. Biological ageing was assessed by different methods including phenotypic age, phenotypic age acceleration (PhenoAgeAccel), biological age and biological age acceleration (BioAgeAccel). Correlations were analyzed by weighted linear regression and restricted cubic spline models. RESULTS: Of the 11,729 participants included, the mean age was 47.41 ± 0.36 years and 5983 (51.01%) were female. The mean phenotypic and biological ages were 42.96 ± 0.41 and 46.75 ± 0.39 years, respectively, and the mean LE8 score was 67.71 ± 0.35. After adjusting for potential confounders, higher LE8 scores were associated with lower phenotypic age, biological age, PhenoAgeAccel, and BioAgeAccel, with nonlinear dose-response relationships. Negative associations were also found between health behavior and health factor scores and biological ageing, and were stronger for health factors. In health factor-specific analyses, the ß negativity was greater for blood glucose and blood pressure. The inverse correlations of LE8 scores with phenotypic age and biological age in the stratified analyses remained solid across strata. CONCLUSIONS: LE8 and its subscale scores were strongly negatively related to biological ageing. Encouraging optimal CVH levels may be advantageous in preventing and slowing down ageing.


Assuntos
Envelhecimento , Glicemia , Estados Unidos , Humanos , Adulto , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Inquéritos Nutricionais , Pressão Sanguínea
7.
Sci Total Environ ; 905: 166994, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37742984

RESUMO

Soils, especially in farmlands, are key media for the transmission of antibiotic resistance genes (ARGs) and their hosts from the environment to humans. Sloping farmland is an important agricultural resource, but there lack of studies on the fate and risk of ARGs in sloping land. Also, the behavior and drivers of ARGs in response to slope gradient and position are unclear. Here, metagenomics was used to investigate the profiles of ARGs, mobile genetic elements, and microbial communities in soils from lands of five slope gradients (5°, 10°, 15°, 20°, and 25°) with two slope positions (uphill and downhill). Results showed that while the abundance (except 15°) and diversity (except 20°) of ARGs increased as the slope gradient increased, the diversity of ARGs with health risk, especially the high-risk ones, decreased. For slope positions, abundant and diverse ARGs were more likely to accumulate at downhill. Furthermore, 52 bacterial genera and 12 human pathogenic bacteria (HPB) species were identified as the potential hosts for ARGs with high risk, and abundant HPB species were also detected in the soils with low gradients at downhill. Moreover, the structural equation model analysis revealed that the slope gradient and the slope position have both direct and indirect effects on the abundance of ARGs. Further correlation analysis revealed that the slope gradient has a positive effect (p < 0.05) on nitrite nitrogen in the soils. Also, the slope position has a negative effect (p < 0.05) on total phosphorus and microbial nitrogen, while positively affected (p < 0.05) on particulate nitrogen and microbial carbon, which were the key factors driving the behavior of ARGs. Overall, this study provided comprehensive information on ARGs with health risks and their potential pathogenic hosts in sloping farmland. It can be important for controlling antibiotic resistance transmission and be consistent with the One Health framework.


Assuntos
Antibacterianos , Genes Bacterianos , Humanos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , Solo/química , Medição de Risco , Nitrogênio , Microbiologia do Solo
8.
Environ Sci Pollut Res Int ; 30(49): 108162-108175, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37749471

RESUMO

The metagenomics-based behavior and risk of antibiotic resistance genes (ARGs) were investigated during cattle manure thermophilic anaerobic digestion with tetracycline and copper, namely, bulk-copper oxide, nano-copper oxide, and copper sulfate, which are common feed additives. Although bulk-copper oxide reduced ARGs' diversity, it enriched high-risk ARGs the most than the other two copper species, while copper sulfate could strongly mitigate the ARG risk by decreasing their abundances. Compared to corresponding individual effects, copper and tetracycline combinations may decrease ARGs' co-occurrence potential by 22.0%, and particularly, tetracycline combined separately with copper sulfate and nano-copper oxide reduces the ARGs' risk in abundance (by 7.2%) and human health (by 4.0%). These were mainly driven by bioavailable copper, volatile fatty acids, and pH, as well as the main potential hosts in phyla Firmicutes, Coprothermobacterota, and Euryarchaeota. Notably, the twin risks of pathogenicity and ARGs should be emphasized due to the ARGs' positive correlation with human pathogens of Clostridioides difficile and Arcobacter peruensis. These findings are important for understanding the potential ARGs' risk in treatments of livestock wastes containing feed additives of different sizes and speciation.


Assuntos
Antibacterianos , Esterco , Humanos , Bovinos , Animais , Antibacterianos/farmacologia , Cobre , Sulfato de Cobre , Anaerobiose , Genes Bacterianos , Tetraciclina/farmacologia , Óxidos
9.
J Affect Disord ; 337: 57-65, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37244542

RESUMO

BACKGROUND: Few studies have investigated the relationship between systemic oxidative stress status and depression. The oxidative balance score (OBS) was used to assess systemic oxidative stress status, with higher OBS scores implying exposure to more antioxidants. This study aimed to explore whether OBS is associated with depression. METHODS: 18,761 subjects from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018 were selected. Depression was diagnosed by the Patient Health Questionnaire (PHQ-9, score ≥ 10). OBS was scored by 20 dietary and lifestyle factors. Weighted logistic regression and restricted cubic splines (RCS) were used to assess the association between OBS and depression. RESULTS: The prevalence of depression was 8.42 %. There was a significant negative nonlinear relationship between OBS, dietary OBS, lifestyle OBS and depression (p for nonlinear < 0.05). Compared to the lowest quartile of OBS, the adjusted ORs for the highest quartile of OBS, dietary OBS, and lifestyle OBS and depression were 0.290 (95 % CI: 0.193-0.434), 0.500(95 % CI: 0.380-0.658), 0.403(95 % CI: 0.299-0.545) respectively, and all P for trend < 0.001. In stratified analyses, three OBS were negatively associated with the odds of depression across sex groups (all P for trend < 0.05), and the OR was smaller in the female group than in the male group. LIMITATIONS: Cross-sectional data and absence of drug considerations. CONCLUSIONS: OBS was strongly negatively associated with depression, especially in females. The findings underline the significance of adhering to an antioxidant diet and lifestyle, which helps prevent depression and appears to be of greater benefit to women.


Assuntos
Antioxidantes , Depressão , Humanos , Masculino , Feminino , Inquéritos Nutricionais , Depressão/epidemiologia , Estudos Transversais , Antioxidantes/metabolismo , Estresse Oxidativo , Dieta
10.
Environ Pollut ; 322: 121253, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773688

RESUMO

Soil is a vital contributor to the production of nitrous oxide (N2O), a potent greenhouse gas, through the nitrogen cycle, which can be influenced by accumulated vanadium (V) in soil but it is less pronounced. This work investigated the response of soil N2O fluxes along with major nitrogen cycle products (ammonium, nitrate, and nitrite) to different vanadium contents (0, 200, 500, 800, and 1100 mg V/kg), and the underlying microbial mechanisms. N2O fluxes was significantly influenced at high V content (1100 mg V/kg) due to its corresponding high water-soluble V content. Microbial composition and their correlations with nitrogen cycle products showed that microbes in dominant phyla (Actinobacteriota and Proteobacteria) and genus (Nocardioides, Lysobacter, Sphingomonas, and Marmoricola) might be the important contributor to N2O fluxes regardless of the V content. Moreover, high V contents (800, and 1100 mg V/kg) could enrich microbes involved in nitrogen cycle, but weaken their correlations with nitrogen-related products, such as in genus Bacillus, and change microbial correlation with N2O from associated with nitrate and nitrite to ammonium. Meanwhile, functional gene predication results showed that denitrifying genes nirKS and nosZ were negatively and positively correlated with V contents, respectively. These all further suggested that the shift of possible N2O metabolic pathways induced mainly by water-soluble V might be the underlying reason for N2O fluxes. These findings promote an understanding of the potential effect of metal pollution on N2O fluxes in soil.


Assuntos
Compostos de Amônio , Microbiota , Vanádio/toxicidade , Nitratos , Nitritos , Ciclo do Nitrogênio , Solo , Óxido Nitroso/análise , Nitrogênio/análise , Microbiologia do Solo
11.
Environ Sci Pollut Res Int ; 29(42): 62994-63004, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35449326

RESUMO

Roles of bulk-, micron-, and nano-copper oxide (CuO) on methane production, microbial diversity, functions during thermophilic anaerobic digestion (AD) were investigated in this study. Results showed that bulk-, micron-, and nano-CuO promoted methane production by 27.8%, 47.6%. and 83.1% compared to the control group, respectively. Microbial community analysis demonstrated that different particle sizes could cause various shifts on bacteria community, while had little effect on archaeal diversity. Thereinto, bacteria belonging to phylum Firmicutes and Coprothermobacterota dominated in enhanced hydrolysis process in groups with nano-CuO and bulk-CuO, respectively, while micron-CuO had stronger promotion on the abundances of hydrolytic and fermentative bacteria belonging to families Peptostreptococcaceae, Caloramatoraceae, Erysipelotrichaceae, and Clostridiaceae, than other two CuO sizes. Metabolic pathways revealed that energy-related metabolism and material transformation in bacteria were only boosted by micron-CuO, and nano-CuO and bulk-CuO were important to methanogenic activity, stimulating energy consumption and methane metabolism, respectively.


Assuntos
Esterco , Metano , Anaerobiose , Animais , Bactérias/metabolismo , Reatores Biológicos , Bovinos , Cobre , Firmicutes/metabolismo , Esterco/microbiologia , Metano/metabolismo , Óxidos , Tamanho da Partícula
12.
Bioresour Technol ; 347: 126709, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35033645

RESUMO

This work investigated the metagenomics-based behavior of antibiotic resistance genes (ARGs) during cattle manure anaerobic digestion with zinc oxide nanoparticles (ZnO NPs) that are commonly used as animal feed additives. The 6.6% decrease in total ARGs abundance while remained unchanged ARGs diversity with ZnO NPs (5 mg/g total solid), suggested ZnO NPs may mitigate ARGs risk by abundance. Also, ZnO NPs affected ARGs with mechanisms specifically of antibiotic inactivation and antibiotic target change, and declined potential hosts' abundance (bacterial genus Ruminiclostridium, Riminococcus, and Paenibacillus) which mainly contributed to the decreased ARGs' abundance. Besides, microbial chemotaxis decreased by 17% with ZnO NPs compared to that without nanoparticles indicated a depression on potential hosts, who could develop the mechanism to adapt to altered digestion conditions, which probably inhibited the ARGs' propagation. These findings are important to promote understanding of the potential ARGs risks in treatments of livestock wastes containing animal feed additives.


Assuntos
Nanopartículas , Óxido de Zinco , Anaerobiose , Animais , Antibacterianos/farmacologia , Bovinos , Resistência Microbiana a Medicamentos , Genes Bacterianos/genética , Esterco , Metagenômica
14.
J Immunol Res ; 2020: 4598476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123602

RESUMO

Natural killer (NK) cells are innate immune effectors with potent antitumor activity. However, tumor cells can create an immunosuppressive microenvironment to escape immune surveillance. Although accumulating evidence indicates that microenvironmental hypoxia plays an important role in favoring tumor development and immune evasion, it remains unclear by what means hypoxia directly impairs NK cell antitumor activity. In this study, we confirmed that hypoxic NK cells showed significantly lower cytotoxicity against tumor cells. Consistent with this finding, we found that the reduction in NK cell cytotoxicity resulting from hypoxia correlated to the lower expression of granzyme B, IFN-γ, and degranulation marker CD107a, as well as activating receptors including NKp30, NKp46, and NKG2D expressed on the surface of NK cells. More importantly, we further demonstrated that a reduction in the phosphorylation levels of ERK and STAT3 secondary to hypoxia was strongly associated with the attenuated NK cell cytotoxicity. Focusing on the mechanism responsible for reduced phosphorylation levels of ERK and STAT3, we reveal that the activation of protein tyrosine phosphatase SHP-1 (Src homology region 2 domain-containing phosphatase-1) following hypoxia might play an essential role in this process. By knocking down SHP-1 or blocking its activity using a specific inhibitor TPI-1, we were able to partially restore NK cell cytotoxicity under hypoxia. Taken together, we demonstrate that hypoxia could impair NK cell cytotoxicity by decreasing the phosphorylation levels of ERK and STAT3 in a SHP-1-dependent manner. Therefore, targeting SHP-1 could provide an approach to enhance NK cell-based tumor immunotherapy.


Assuntos
Hipóxia/imunologia , Células Matadoras Naturais/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Linhagem Celular , Microambiente Celular , Citotoxicidade Imunológica , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Receptor 3 Desencadeador da Citotoxicidade Natural/genética , Receptor 3 Desencadeador da Citotoxicidade Natural/metabolismo , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 6/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Timidina/análogos & derivados , Timidina/farmacologia , Evasão Tumoral
15.
Appl Biochem Biotechnol ; 192(1): 313-324, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32378079

RESUMO

An emerging contaminant, micron-sized zero valent iron (mZVI) has been reported to be accumulated in waste activated sludge (WAS). In the present study, the potential effects of mZVI on WAS anaerobic fermentation performance, as well as the shift of the microbial community composition and function, were assessed. Results from batch experiments indicated that a particular concentration of mZVI (1.5 g/L, in the range of 0.0 to 5.0 g/L) improved volatile fatty acids (VFA) accumulation by 4.84 times that in the control group, the ability (dosage dependent) to remove phosphorus, and the dewaterability of fermented WAS from 126 ± 5 s (control group) to 104 ± 3 s (group with 1.5 g/L mZVI). Furthermore, high-throughput sequencing revealed that mZVI had no significant impact on the shift of microbial community structure, but directly stimulated the functional performance related to anaerobic fermentation. This study will provide new insights into the mZVI application and its effect on WAS utilization.


Assuntos
Ferro/química , Microbiota , Esgotos , Águas Residuárias , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Cromatografia Gasosa , Ácidos Graxos Voláteis/química , Fermentação , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Hidrólise , Fósforo , Purificação da Água
16.
Chemosphere ; 241: 125072, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31627109

RESUMO

Alkaline fermentation has been considered as one of the efficient methods for waste activated sludge (WAS) treatment, but usually limited by microbial fermentation activities under extreme pH condition. One newly isolated alkali-tolerant strain Corynebacterium pollutisoli SPH6 was used to assess its potential role and effect on WAS alkaline fermentation process. Results from response surface method showed that the optimal organic nitrogen degradation rate by SPH6 was obtained under temperature of 35 °C, initial pH of 10, shaking speed of 80 rpm, inoculation ratio of 6.5%. Batch-scale experiments demonstrated that, compared with the control group, the inoculation of SPH6 finally achieved higher productions with 13.4% of carbohydrates, 27.1% of protein and 25.4% of total volatile fatty acids (VFAs), and more predominant functional bacteria characterized by high-throughput sequencing, such as genera Acinetobacter in phylum Proteobacteria, Tissierella and Acetoanaerobium in phylum Firmicutes. The strain SPH6 might play a vital role in maintaining and facilitating the growth and diversity of functional bacteria in WAS alkaline fermentation process. It has implied promising practical application of the present strain in enhancing WAS reduction and utilization.


Assuntos
Reatores Biológicos/microbiologia , Corynebacterium/fisiologia , Eliminação de Resíduos Líquidos/métodos , Álcalis , Bactérias/metabolismo , Biodegradação Ambiental , Carboidratos , Ácidos Graxos Voláteis/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Proteínas/química , Esgotos/química
17.
Bioresour Technol ; 269: 113-120, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30153549

RESUMO

A novel bacterium Corynebacterium pollutisoli SPH6 was added in A/O-MBBR system to explore its potential in nitrogen removal. Sodium acetate was found to be its favorable carbon sources compared to glucose, sucrose and methanol. Response surface methodology analysis revealed that SPH6 has the maximum specific degradation rate of total nitrogen (4.9302 mg N/(mg·cells·h-1)) with the temperature of 30.5 °C, pH of 7.97, inoculation ratio of 7.73% and the ratio of chemical oxygen demand and total nitrogen (COD/TN) of 7.77. The inoculation of SPH6 in A/O-MBBR demonstrated that the strain SPH6 could substantially improve the TN removal efficiency with 20% averagely. The results of high-throughput sequencing showed that the inoculation of SPH6 would essentially improve the microbial community involving nitrogen removal genus such as Hydrogenophaga, Desulfuromonas, and Desulfomicrobium. This study is of importance in providing microbial sources for bioaugmentation in nitrogen removal of wastewater treatment.


Assuntos
Biofilmes , Corynebacterium , Desnitrificação , Reatores Biológicos , Nitrogênio , Eliminação de Resíduos Líquidos , Águas Residuárias
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