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1.
Plant Commun ; 5(10): 100999, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-38853433

RESUMO

Grain weight, a key determinant of yield in rice (Oryza sativa L.), is governed primarily by genetic factors, whereas grain chalkiness, a detriment to grain quality, is intertwined with environmental factors such as mineral nutrients. Nitrogen (N) is recognized for its effect on grain chalkiness, but the underlying molecular mechanisms remain to be clarified. This study revealed the pivotal role of rice NODULE INCEPTION-LIKE PROTEIN 3 (OsNLP3) in simultaneously regulating grain weight and grain chalkiness. Our investigation showed that loss of OsNLP3 leads to a reduction in both grain weight and dimension, in contrast to the enhancement observed with OsNLP3 overexpression. OsNLP3 directly suppresses the expression of OsCEP6.1 and OsNF-YA8, which were identified as negative regulators associated with grain weight. Consequently, two novel regulatory modules, OsNLP3-OsCEP6.1 and OsNLP3-OsNF-YA8, were identified as key players in grain weight regulation. Notably, the OsNLP3-OsNF-YA8 module not only increases grain weight but also mitigates grain chalkiness in response to N. This research clarifies the molecular mechanisms that orchestrate grain weight through the OsNLP3-OsCEP6.1 and OsNLP3-OsNF-YA8 modules, highlighting the pivotal role of the OsNLP3-OsNF-YA8 module in alleviating grain chalkiness. These findings reveal potential targets for simultaneous enhancement of rice yield and quality.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Grão Comestível/crescimento & desenvolvimento , Nitrogênio/metabolismo , Plantas Geneticamente Modificadas/genética , Sementes/genética , Sementes/metabolismo , Sementes/crescimento & desenvolvimento
2.
Biochimie ; 216: 181-193, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37748748

RESUMO

Malassezia globosa is abundant and prevalent on sebaceous areas of the human skin. Genome annotation reveals that M. globosa possesses a repertoire of secreted hydrolytic enzymes relevant for lipid and protein metabolism. However, the functional significance of these enzymes is uncertain and presence of these genes in the genome does not always translate to expression at the cutaneous surface. In this study we utilized targeted RNA sequencing from samples isolated directly from the skin to quantify gene expression of M. globosa secreted proteases, lipases, phospholipases and sphingomyelinases. Our findings indicate that the expression of these enzymes is dynamically regulated by the environment in which the fungus resides, as different growth phases of the planktonic culture of M. globosa show distinct expression levels. Furthermore, we observed significant differences in the expression of these enzymes in culture compared to healthy sebaceous skin sites. By examining the in situ gene expression of M. globosa's secreted hydrolases, we identified a predicted aspartyl protease, MGL_3331, which is highly expressed on both healthy and disease-affected dermatological sites. However, molecular modeling and biochemical studies revealed that this protein has a non-canonical active site motif and lacks measurable proteolytic activity. This pseudoprotease MGL_3331 elicits a heightened IgE-reactivity in blood plasma isolated from patients with atopic dermatitis compared to healthy individuals and invokes a pro-inflammatory response in peripheral blood mononuclear cells. Overall, our study highlights the importance of studying fungal proteins expressed in physiologically relevant environments and underscores the notion that secreted inactive enzymes may have important functions in influencing host immunity.


Assuntos
Alérgenos , Malassezia , Humanos , Alérgenos/metabolismo , Malassezia/genética , Malassezia/metabolismo , Leucócitos Mononucleares/metabolismo , Pele/metabolismo , Lipase/metabolismo
3.
Cell Rep Methods ; 3(9): 100569, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37751693

RESUMO

Alloantibody recognition of donor human leukocyte antigen (HLA) is associated with poor clinical transplantation outcomes. However, the molecular and structural basis for the alloantibody-HLA interaction is not well understood. Here, we used a hybrid structural modeling approach on a previously studied alloantibody-HLA interacting pair with inputs from ab initio, in silico, and in vitro data. Highly reproducible cross-linking mass spectrometry data were obtained with both discovery- and targeted mass spectrometry-based approaches approaches. The cross-link information was then used together with predicted antibody Fv structure, predicted antibody paratope, and in silico-predicted interacting surface to model the antibody-HLA interaction. This hybrid structural modeling approach closely recapitulates the key interacting residues from a previously solved crystal structure of an alloantibody-HLA-A∗11:01 pair. These results suggest that a predictive-based hybrid structural modeling approach supplemented with cross-linking mass spectrometry data can provide functionally relevant structural models to understand the structural basis of antibody-HLA mismatch in transplantation.


Assuntos
Antígenos HLA , Antígenos de Histocompatibilidade , Humanos , Antígenos de Histocompatibilidade Classe II , Isoanticorpos , Região Variável de Imunoglobulina , Espectrometria de Massas
4.
Angew Chem Int Ed Engl ; 62(33): e202307553, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37340712

RESUMO

Ceramidases (CDases) are important in controlling skin barrier integrity by regulating ceramide composition and affording downstream signal molecules. While the functions of epidermal CDases are known, roles of neutral CDases secreted by skin-residing microbes are undefined. Here, we developed a one-step fluorogenic substrate, S-B, for specific detection of bacterial CDase activity and inhibitor screening. We identified a non-hydrolyzable substrate mimic, C6, as the best hit. Based on C6, we designed a photoaffinity probe, JX-1, which efficiently detects bacterial CDases. Using JX-1, we identified endogenous low-abundance PaCDase in a P. aeruginosa monoculture and in a mixed skin bacteria culture. Harnessing both S-B and JX-1, we found that CDase activity positively correlates with the relative abundance of P. aeruginosa and is negatively associated with wound area reduction in clinical diabetic foot ulcer patient samples. Overall, our study demonstrates that bacterial CDases are important regulators of skin ceramides and potentially play a role in wound healing.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Ceramidase Neutra/química , Amidoidrolases , Ceramidases , Ceramidas/química
5.
Ying Yong Sheng Tai Xue Bao ; 33(11): 3087-3096, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36384843

RESUMO

Ecosystem service (ES) bundle is a combination of various ecosystem services, serving as an indicator for the trade-off or synergy relationship among ecosystem services. Identifying the trade-off and synergy within ecosystem service bundles is helpful for realizing regional management and policymaking at the ES-bundle level. In this study, based on the InVEST model, the spatial composition, trade-off, and synergy of ES bundles, and their influencing factors were clarified using correlation analysis, cluster analysis, principal component analysis, and redundancy analysis. The results showed that the ESs in the Ziwuling Region (ZWLR) were generally improved from 2000 to 2017. The high-value area of soil conservation was concentrated in the northern part of the ZWLR, whereas other high-value areas of ESs were concentrated in the central and southern parts. According to the results of the cluster analysis, the ZWLR could be divided into four ES-bundles at pixel level. There was a strong tradeoff between water yield service and soil conservation in the core protected bundle, and a strong tradeoff between habitat quality, water yield service and food production in grain production bundle. The relationship between ESs in ecologi-cal transition bundle and ecologically fragile bundle was dominated by synergetic relationship. The ESs were affec-ted by both natural conditions and human activities. Vegetation cover, precipitation, and elevation had positive effects on the ESs, while temperature, the proportion of construction land, and population density had negative effects.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Conservação dos Recursos Naturais/métodos , Solo , Água , China
6.
Plant Cell Environ ; 45(5): 1520-1536, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35150141

RESUMO

Nitrogen (N) is an essential macronutrient for crop growth and yield. Improving the N use efficiency (NUE) of crops is important to agriculture. However, the molecular mechanisms underlying NUE regulation remain largely elusive. Here we report that the OsNLP3 (NIN-like protein 3) regulates NUE and grain yield in rice under N sufficient conditions. OsNLP3 transcript level is significantly induced by N starvation and its protein nucleocytosolic shuttling is specifically regulated by nitrate. Loss-of-function of OsNLP3 reduces plant growth, grain yield, and NUE under sufficient nitrate conditions, whereas under low nitrate or different ammonium conditions, osnlp3 mutants show no clear difference from the wild type. Importantly, under sufficient N conditions in the field, OsNLP3 overexpression lines display improved grain yield and NUE compared with the wild type. OsNLP3 orchestrates the expression of multiple N uptake and assimilation genes by directly binding to the nitrate-responsive cis-elements in their promoters. Overall, our study demonstrates that OsNLP3, together with OsNLP1 and OsNLP4, plays overlapping and differential roles in N acquisition and NUE, and modulates NUE and the grain yield increase promoted by N fertilizer. Therefore, OsNLP3 is a promising candidate gene for the genetic improvement of grain yield and NUE in rice.


Assuntos
Oryza , Grão Comestível/metabolismo , Fertilizantes , Nitratos/metabolismo , Nitrogênio/metabolismo , Oryza/genética , Oryza/metabolismo
7.
Plant Biotechnol J ; 19(3): 448-461, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32876985

RESUMO

Nitrogen (N) is one of the key essential macronutrients that affects rice growth and yield. Inorganic N fertilizers are excessively used to boost yield and generate serious collateral environmental pollution. Therefore, improving crop N use efficiency (NUE) is highly desirable and has been a major endeavour in crop improvement. However, only a few regulators have been identified that can be used to improve NUE in rice to date. Here we show that the rice NIN-like protein 4 (OsNLP4) significantly improves the rice NUE and yield. Field trials consistently showed that loss-of-OsNLP4 dramatically reduced yield and NUE compared with wild type under different N regimes. In contrast, the OsNLP4 overexpression lines remarkably increased yield by 30% and NUE by 47% under moderate N level compared with wild type. Transcriptomic analyses revealed that OsNLP4 orchestrates the expression of a majority of known N uptake, assimilation and signalling genes by directly binding to the nitrate-responsive cis-element in their promoters to regulate their expression. Moreover, overexpression of OsNLP4 can recover the phenotype of Arabidopsis nlp7 mutant and enhance its biomass. Our results demonstrate that OsNLP4 plays a pivotal role in rice NUE and sheds light on crop NUE improvement.


Assuntos
Arabidopsis , Oryza , Fertilizantes , Nitratos , Nitrogênio , Oryza/genética
8.
Sci Rep ; 6: 27795, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27293103

RESUMO

Nitrogen is essential for plant survival and growth. Excessive application of nitrogenous fertilizer has generated serious environment pollution and increased production cost in agriculture. To deal with this problem, tremendous efforts have been invested worldwide to increase the nitrogen use ability of crops. However, only limited success has been achieved to date. Here we report that NLP7 (NIN-LIKE PROTEIN 7) is a potential candidate to improve plant nitrogen use ability. When overexpressed in Arabidopsis, NLP7 increases plant biomass under both nitrogen-poor and -rich conditions with better-developed root system and reduced shoot/root ratio. NLP7-overexpressing plants show a significant increase in key nitrogen metabolites, nitrogen uptake, total nitrogen content, and expression levels of genes involved in nitrogen assimilation and signalling. More importantly, overexpression of NLP7 also enhances photosynthesis rate and carbon assimilation, whereas knockout of NLP7 impaired both nitrogen and carbon assimilation. In addition, NLP7 improves plant growth and nitrogen use in transgenic tobacco (Nicotiana tabacum). Our results demonstrate that NLP7 significantly improves plant growth under both nitrogen-poor and -rich conditions by coordinately enhancing nitrogen and carbon assimilation and sheds light on crop improvement.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Carbono/metabolismo , Nitrogênio/metabolismo , Fatores de Transcrição/genética , Agricultura , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Biomassa , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Regulação para Cima
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1565-70, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-30001064

RESUMO

Quartz Volume Diffuser(QVD) is used in the observing system of Space-Borne differential optical absorption spectrometer. The precision of observed solar spectrum directly influences the accuracy of the gas retrievals. Therefore the QVD is required for well Lambert feature to ensure the accuracy of full field solar spectrum, and it can provide uniformity source in the observing view of the instrument. Using bidirectional reflectance distribution function(BRDF) measurement instrument, adopting the powder pressboard of F4(polytetrafluoroethylene(PTFE)), QVD's BRDF is measured by choosing the relative measurement method. Four kinds of QVD's BRDF is obtained in the range of 180~880 nm, the observing view of -70°ï½ž+70°. Two kinds of QVD which has a well Lambert feature are selected by analyzing the QVD's BRDF. The diffuse sunlight measured by QVD and F4 is compared, which show that QVD has well scattering properties with regard to solar spectrum and can be selected as the measuring diffuser. That supports for next Ultraviolet irradiation measurement, atomic oxygen erosion measurement and comparison measurement.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2578-82, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26669171

RESUMO

Space-borne differential optical absorption spectrometer is a nadir viewing wide field imaging spectrometer, which adopts two-dimensional CCD detector arrays. The pixel response non-uniformity exists in each column of spatial dimension, which will introduce high-frequency instrument-related spectral structures in the measurement data. However, the non-uniformity calibration of space-born imaging spectrometer is difficulty due to two factors: the spectral smile effect and the large field of view. For this reason, a method of non-uniformity calibration is discussed in detail. The result shows that the spectral smile effect and non-uniformity of full FOV image are corrected effectively, and high-frequency instrument-related structures in the measurement data are removed.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 2049-53, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26717777

RESUMO

Spectral calibration of space-born imaging spectrometers based on spectrum-matching technique is presented, which adopts atmospheric absorption lines as the matching lines, and chooses correlation coefficient method as the criteria. In order to simulation the onboard spectral calibration, the spectrum-matching technique is applied on the imaging spectrometers that after the vibration test. The vibration test is able to simulation the launching. The spectral resolution, center wavelength of two-dimensional pixel is determined during onboard spectral calibration. As the calibration results show, the spectral resolution of imaging spectrometers after the vibration test is 0.40 nm, it is the same comparing to the value before the vibration, the wavelength shifts 0.08 nm towards the long wave for the spectral pixels, and the spectral smile is determined for all spatial elements, which shifts towards the short wave direction, with the max smile value is 0.96 nm, the result is similar to that before the vibration. As a result, the spectrum-matching technique is tested and verified.

12.
Fitoterapia ; 98: 149-55, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25088970

RESUMO

The purpose of this study is to elucidate the bioactive components responsible for the the α-glucosidase inhibitory activity detected in the EtOAc extract of the mushroom Hydnellum concrescens. Two new p-terphenyl derivatives, concrescenins A (1) and B (2), in along with six known compounds thelephantins L (3), I (4), J (5), K (6), dihydroauran-tiacin dibenzoate (7), and curtisian A (8) were isolated from the fruiting bodies of H. concrescens. Their chemical structures were elucidated by NMR experiments. Compounds 1-4 and 6-8 showed the inhibitory activity against α-glucosidase with the IC50 of 0.99, 3.11, 4.53, 18.77, 2.98, 5.16, and 8.34 µM, respectively. Kinetic analysis of α-glucosidase indicated that compounds 1 and 2 inhibited the activity of α-glucosidase in a noncompetitive fashion with a Ki value of 0.02 and 0.21 µM, respectively. In antioxidant evaluation, compounds 1 and 4 showed weak DPPH scavenging activity (EC50=82.50 and 161.75 µM) and weak reducing ability (EC50=193.57 and 152.94 µM). The current research supports the potential use of mushroom-derived p-terphenyl derivatives for the treatment of diabetes.


Assuntos
Agaricales/química , Basidiomycota/química , Inibidores de Glicosídeo Hidrolases/química , Compostos de Terfenil/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , China , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Estrutura Molecular , Compostos de Terfenil/isolamento & purificação , alfa-Glucosidases/metabolismo
13.
Huan Jing Ke Xue ; 34(5): 1930-6, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23914550

RESUMO

An acidophilic iron-sulfur oxidizing bacterium LY01 was isolated from acid mine drainage of coal in Guizhou Province, China. Strain LY01 was identified as Acidithiobacillusferrooxidans by morphological and physiological characteristics, and phylogenetic analysis of its 16S rRNA gene sequence. Strain LY01 was able to grow using ferrous ion (Fe2+), elemental sulfur (S0) and pyrite as sole energy source, respectively, but significant differences in oxidation efficiency and bacterial growth were observed when different energy source was used. When strain LY01 was cultured in 9K medium with 44.2 g x L(-1) FeSO4.7H2O as the substrate, the oxidation efficiency of Fe2+ was 100% in 30 h and the cell number of strain LY01 reached to 4.2 x 10(7) cell x mL(-1). When LY01 was cultured in 9K medium with 10 g x L(-1) S0 as the substrate, 6.7% S0 oxidation efficiency, 2001 mg x L(-1) SO4(2-) concentration and 8.9 x 10(7) cell x mL(-1) cell number were observed in 21 d respectively. When LY01 was cultured with 30 g x L(-1) pyrite as the substrate, the oxidation efficiency of pyrite, SO4(2-) concentration and cell number reached 10%, 4443 mg x L(-1) and 3.4 x 10(8) cell x mL(-1) respectively in 20 d. The effects of different heavy metals (Ni2+, Pb2+) on oxidation activity of strain LY01 cultured with pyrite were investigated. Results showed that the oxidation activity of strain LY01 was inhibited to a certain extent with the addition of Ni2+ at 10-100 mg x L(-1) to the medium, but the addition of 10-100 mg x L(-1) Pb2+ had no effect on LY01 activity.


Assuntos
Acidithiobacillus/metabolismo , Ferro/metabolismo , Enxofre/metabolismo , Águas Residuárias/microbiologia , Acidithiobacillus/isolamento & purificação , Biodegradação Ambiental , China , Carvão Mineral , Compostos Ferrosos/metabolismo , Mineração , Oxirredução , Enxofre/isolamento & purificação
14.
Huan Jing Ke Xue ; 34(4): 1598-604, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23798148

RESUMO

Effects of incorporation of the biochars generated from rice straw and peanut straw at different temperatures on soil pH and Pb(II) adsorption were investigated with two variable charge soils. The soil pH increased by 1.04-3.00 units, and the increase in soil pH increased with the rise of pyrolysis temperature of the biochar. Results from adsorption isotherm experiments indicated that the incorporation of the biochar enhanced the adsorption of Pb(II) by two soils. The adsorption of Pb(II) was increased by 12.6% -57.6%, when the initial concentration of Pb(II) is 2 mmol x L(-1). The adsorption also increased with rising pH. Freundlich and Langmuir equations can be used to fit the adsorption isotherms of Pb(II), but the Freundlich equation fitted the adsorption data better, the r-values are above 0.94. Soils incorporated with peanut straw char have a greater adsorption capacity for Pb(II) than these incorporated with rice straw char as predicted by the parameters of k and Q(m) in Freundlich and Langmuir equations, respectively. The biochars generated at 400 degrees C have a greater enhancement on Pb(II) adsorption by soils than 300 degrees C and 500 degrees C. Desorption results showed that the desorption of Pb(II) for the treatments with biochar added was greater than that for the control, but the amount of desorbed Pb(II) was much lower than that of adsorbed Pb(II). These results suggested that the enhanced adsorption of Pb(II) by incorporation of the biochars involved at least two mechanisms: electrostatic adsorption and non-electrostatic adsorption.


Assuntos
Carvão Vegetal , Recuperação e Remediação Ambiental/métodos , Chumbo/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Solo/química , Adsorção , Cátions Bivalentes , Concentração de Íons de Hidrogênio , Chumbo/química , Caules de Planta/química , Poluentes do Solo/química , Temperatura
15.
Zhonghua Yi Xue Za Zhi ; 92(7): 464-7, 2012 Feb 21.
Artigo em Chinês | MEDLINE | ID: mdl-22490967

RESUMO

OBJECTIVE: To explore the differences of working memory task performance between male patients with heroin dependence in methadone maintenance treatment (MMT) and healthy controls (HC). METHODS: A total of 42 heroin-dependent patients at Huainan City Psychiatric Hospital from May 2011 to October 2011 were compared with 31 gender- and age-matched HCs on such working memory tests as visual-space, visual-verbal and visual-face. Then the accurate rate and reaction time of the above tasks were between two groups. RESULTS: The participants with anxiety or depression were excluded. All MMT subjects were required to have negative urine toxicology screening tests. The accurate rate of verbal working memory of the patients was worse than that of HCs (83% ± 9% vs 89% ± 10%). And the difference was significant between two groups (t(71) = -2.631, P = 0.010). The accurate rate of visual-object and visual-spatial working memory showed no significant differences between two groups (P > 0.05). The differences in reaction time on these tasks showed no statistical significance between two groups (P > 0.05). In addition, the dose of methadone and the duration of MMT revealed no significant effects on the performance of working memory and executive functions. CONCLUSION: The disproportion impairment of patients on space, verbal and face working memory is probably due to the differential heroin-mediated injuries of encephalic regions. Methadone has no effect on working memory and executive functions in the patients with a history of heroin use during maintenance treatment intervention.


Assuntos
Dependência de Heroína/tratamento farmacológico , Memória de Curto Prazo/efeitos dos fármacos , Metadona/uso terapêutico , Adulto , Estudos de Casos e Controles , Dependência de Heroína/psicologia , Humanos , Masculino
16.
Huan Jing Ke Xue ; 32(1): 272-6, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21404698

RESUMO

In this study, Acidithiobacillus ferrooxidans LX5 was cultured in 9K medium with pyrite and ferrous sulfate as the substrates. Results showed that the number of A. ferrooxidans LX5 acclimated by pyrite for 20 d was 3.0 x 10(7) cell/mL in the liquid, and the oxidation activity to pyrite was stronger. A. ferrooxidans LX5 cultured for 48 h was 1.0 x 10(8) cell/mL in medium with FeSO4. Extracellular polymeric substance (EPS) produced from A. ferrooxidans LX5 acclimated by pyrite was 2 395 microg/(10(10) cells) three times as much as that cultured with FeSO4. A high-sulfur coal desulfurization experiment were carried out with A. ferrooxidans LX5 domesticated respectively in medium with ferrous sulfate and pyrite. The results showed that the coal desulfurization rate was up to 72.4% after bioleaching for 13 d by A. ferrooxidans LX5 acclimated by pyrite, at the same time, the desulfurization rate was only 47.2% with A. ferrooxidans LX5 cultured with ferrous sulfate and reached 65.8% in 20 d. Therefore, the desulfurization efficiency can be improved of coal and shorten the desulfurization time when A. ferrooxidans LX5 acclimated with pyrite as the substrate.


Assuntos
Acidithiobacillus/metabolismo , Carvão Mineral , Enxofre/isolamento & purificação , Acidithiobacillus/isolamento & purificação , Biodegradação Ambiental , Microbiologia Industrial , Especificidade por Substrato , Enxofre/metabolismo
17.
Bioresour Technol ; 102(2): 854-62, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20875733

RESUMO

Bacterium A1, isolated to enhance nitrogen removal from ammonium-rich wastewater in situ, exhibited an amazing ability to convert ammonium to gaseous nitrogen compounds under fully aerobic conditions, while growing autotrophically or heterotrophically. A1 was identified as Bacillus subtilis by morphological and physiological characteristics, and phylogenetic analysis of its 16S rDNA gene sequence. Nitrogen removal by A1 was analyzed in relation to the ammonium concentration, presence of organic carbon, carbon source, and carbon-to-nitrogen ratio (C/N). The nitrogen balance during 120 h of autotrophic growth in the presence of 104.12±1.27 mg/L NH4+N showed that 20.4±2.7% of NH4+N was removed as gaseous nitrogen compounds, and A1 removed 58.4±4.3% of NH4+N within 60 h of growth in acetate medium at a C/N of 6. A mean ammonium removal rate of 3.52 mg NH4+N/(L h) was achieved in an open wastewater system, indicating great potential of A1 for future full-scale applications.


Assuntos
Bacillus subtilis/isolamento & purificação , Desnitrificação/fisiologia , Processos Heterotróficos/fisiologia , Nitrificação/fisiologia , Nitrogênio/isolamento & purificação , Aerobiose , Bacillus subtilis/crescimento & desenvolvimento , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , Carbono/metabolismo , Dados de Sequência Molecular , Compostos de Amônio Quaternário/isolamento & purificação , Eliminação de Resíduos Líquidos , Purificação da Água
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2719-24, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22250543

RESUMO

A method of interference correction for nondispersive infrared multi-component gas analysis was described. According to the successive integral gas absorption models and methods, the influence of temperature and air pressure on the integral line strengths and linetype was considered, and based on Lorentz detuning linetypes, the absorption cross sections and response coefficients of H2O, CO2, CO, and NO on each filter channel were obtained. The four dimension linear regression equations for interference correction were established by response coefficients, the absorption cross interference was corrected by solving the multi-dimensional linear regression equations, and after interference correction, the pure absorbance signal on each filter channel was only controlled by the corresponding target gas concentration. When the sample cell was filled with gas mixture with a certain concentration proportion of CO, NO and CO2, the pure absorbance after interference correction was used for concentration inversion, the inversion concentration error for CO2 is 2.0%, the inversion concentration error for CO is 1.6%, and the inversion concentration error for NO is 1.7%. Both the theory and experiment prove that the interference correction method proposed for NDIR multi-component gas analysis is feasible.

19.
Huan Jing Ke Xue ; 30(11): 3364-70, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20063755

RESUMO

Sewage sludge contains not only a lot of organic matter and plant nutrients, but also some harmful metals. Recovery of sludge-born metals for sewage sludge of high metal content is very important for safe reutilization of sewage sludge and for economic consideration. Here, we reported a recovery technique for sludge-born copper using bioleaching-solvent extraction-electrodeposition (L-SX-EW) process through batch experiments. The tested sludge containing 7 432 mg/kg Cu was collected from Suzhou Wastewater Treatment Plant located in industrial zone of Suzhou City, Jiangsu, China. The results showed that more than 90% of sludge-born Cu could be solubilized into aqueous phase within 72 h through bioleaching process. Furthermore, soluble Cu in the form of Cu2+ in bioleached sludge filtrate could be concentrated into organic phase through the extracting operation using 2% solvent extractant M5640 under the optimized condition of 1/3 phase ratio (O/A) and pH 2.0, in which Cu2+ extraction efficiency reached more than 95%, whereas the co-existing soluble iron extraction efficiency was less than 10%. Stripping results showed that the Stripping rate of Cu was 80.07% when the phase ratio (O/A) was 2/1 using 1.5 mol/L H2SO4 as stripping solvent. After the concentrated Cu2+ in acidic aqueous phase was electrolyzed for 6 h at 2.1 V bath voltage and 55 degrees C, more than 90% of the Cu2+ recovery efficiency was achieved in the form of elemental Cu powder. There wasn't any wastewater generation in this process. Therefore, this L-SX-EW technique exhibited a potential application for the recovery of metal for heavy metal-loaded sludge.


Assuntos
Cobre/isolamento & purificação , Esgotos/microbiologia , Poluentes do Solo/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Biodegradação Ambiental , Cidades , Cobre/química , Cobre/metabolismo , Eletroquímica , Resíduos Industriais/análise , Metais Pesados/química , Metais Pesados/isolamento & purificação , Esgotos/química , Poluentes do Solo/análise
20.
Huan Jing Ke Xue ; 28(7): 1539-42, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17891966

RESUMO

Heavy metals could be removed from sludge by bioleaching approach, and pathogens in sludge may also be eliminated by the approach. Elimination efficiencies of pathogens in municipal sludge and tannery sludge during bioleaching were studied through batch trials. The results revealed that, after 6 - 7 days of bioleaching compared with the control without bioleaching, the amounts of bacteria in municipal sludge decreased from 1.38 x 10(8) cells/mL to 4.43 x 10(6) cells/mL, and the amounts of bacteria in tannery sludge decreased from 9.23 x 10(5) cells/mL to 4.26 x 10(4) cells/mL. The amounts of sludge bacteria in the control were maintained at the similar level before and after bioleaching. Elimination efficiencies of total coliforms (TC) and fecal coliforms (FC) in bioleached sludge exceeded 99% . But bioleaching approach couldn't eliminate ascarid eggs, as indicating similar levels for survival ascarid eggs before and after sludge bioleaching. Axenic culture of coliforms revealed that the low pH caused by the bioleaching was responsible for pathogens elimination instead of the increases of the concentrations of SO4(2-) and heavy metals.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Esgotos/microbiologia , Curtume , Gerenciamento de Resíduos/métodos , Animais , Ascaris , Reatores Biológicos , Contagem de Colônia Microbiana , Oxirredução , Contagem de Ovos de Parasitas , Esgotos/parasitologia
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