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1.
Chinese Journal of Biotechnology ; (12): 2743-2761, 2023.
Article in Chinese | WPRIM | ID: wpr-981230

ABSTRACT

Nitrate is the main form of inorganic nitrogen that crop absorbs, and nitrate transporter 2 (NRT2) is a high affinity transporter using nitrate as a specific substrate. When the available nitrate is limited, the high affinity transport systems are activated and play an important role in the process of nitrate absorption and transport. Most NRT2 cannot transport nitrates alone and require the assistance of a helper protein belonging to nitrate assimilation related family (NAR2) to complete the absorption or transport of nitrates. Crop nitrogen utilization efficiency is affected by environmental conditions, and there are differences between varieties, so it is of great significance to develop varieties with high nitrogen utilization efficiency. Sorghum bicolor has high stress tolerance and is more efficient in soil nitrogen uptake and utilization. The S. bicolor genome database was scanned to systematically analyze the gene structure, chromosomal localization, physicochemical properties, secondary structure and transmembrane domain, signal peptide and subcellular localization, promoter region cis-acting elements, phylogenetic evolution, single nucleotide polymorphism (SNP) recognition and annotation, and selection pressure of the gene family members. Through bioinformatics analysis, 5 NRT2 gene members (designated as SbNRT2-1a, SbNRT2-1b, SbNRT2-2, SbNRT2-3, and SbNRT2-4) and 2 NAR2 gene members (designated as SbNRT3-1 and SbNRT3-2) were identified, the number of which was less than that of foxtail millet. SbNRT2/3 were distributed on 3 chromosomes, and could be divided into four subfamilies. The genetic structure of the same subfamilies was highly similar. The average value of SbNRT2/3 hydrophilicity was positive, indicating that they were all hydrophobic proteins, whereas α-helix and random coil accounted for more than 70% of the total secondary structure. Subcellular localization occurred on plasma membrane, where SbNRT2 proteins did not contain signal peptides, but SbNRT3 proteins contained signal peptides. Further analysis revealed that the number of transmembrane domains of the SbNRT2s family members was greater than 10, while that of the SbNRT3s were 2. There was a close collinearity between NRT2/3s of S. bicolor and Zea mays. Protein domains analysis showed the presence of MFS_1 and NAR2 protein domains, which supported executing high affinity nitrate transport. Phylogenetic tree analysis showed that SbNRT2/3 were more closely related to those of Z. mays and Setaria italic. Analysis of gene promoter cis-acting elements indicated that the promoter region of SbNRT2/3 had several plant hormones and stress response elements, which might respond to growth and environmental cues. Gene expression heat map showed that SbNRT2-3 and SbNRT3-1 were induced by nitrate in the root and stem, respectively, and SbNRT2-4 and SbNRT2-3 were induced by low nitrogen in the root and stem. Non-synonymous SNP variants were found in SbNRT2-4 and SbNRT2-1a. Selection pressure analysis showed that the SbNRT2/3 were subject to purification and selection during evolution. The expression of SbNRT2/3 gene and the effect of aphid infection were consistent with the expression analysis results of genes in different tissues, and SbNRT2-1b and SbNRT3-1 were significantly expressed in the roots of aphid lines 5-27sug, and the expression levels of SbNRT2-3, SbNRT2-4 and SbNRT3-2 were significantly reduced in sorghum aphid infested leaves. Overall, genome-wide identification, expression and DNA variation analysis of NRT2/3 gene family of Sorghum bicolor provided a basis for elucidating the high efficiency of sorghum in nitrogen utilization.


Subject(s)
Nitrate Transporters , Nitrates/metabolism , Sorghum/metabolism , Anion Transport Proteins/metabolism , Phylogeny , Protein Sorting Signals/genetics , Nitrogen/metabolism , DNA , Gene Expression Regulation, Plant , Plant Proteins/metabolism
2.
Chinese Journal of Stomatology ; (12): 109-117, 2023.
Article in Chinese | WPRIM | ID: wpr-970763

ABSTRACT

Homeostasis is a dynamic balance process of self-regulating. Biological systems remain stable through adapting to changing external conditions to maintain normal life activities. Homeostatic medicine is the science of studying homeostasis of human molecules, cells, organs and the whole body. It is a comprehensive discipline based on maintaining homeostasis to keep human health and assist for diseases prevention and diagnoses. Homeostatic medicine focuses on the whole body and on the role of homeostasis in health and disease, which is expected to provide new ideas and strategies for maintaining health as well as diagnosing and treating diseases. Nitric oxide (NO) plays an important role in the control of multisystem homeostasis. Nitrate is an important substance in regulating NO homeostasis through the nitrate-nitrite-NO pathway. Sialin, nitrate transporter which is located in the cell membrane and cytoplasm, mediates multiple cellular biological functions. The nitrate-nitrite-NO pathway and sialin-mediated biological functions play an important role in the regulation of body homeostasis.


Subject(s)
Humans , Nitrates/metabolism , Nitrites/metabolism , Homeostasis , Nitric Oxide
3.
Braz. j. med. biol. res ; 51(5): e7132, 2018. graf
Article in English | LILACS | ID: biblio-889081

ABSTRACT

Gastroschisis (GS) is an abdominal wall defect that results in histological and morphological changes leading to intestinal motility perturbation and impaired absorption of nutrients. Due to its anti-inflammatory, antioxidant, and neuroprotective effects, cannabidiol (CBD) has been used as a therapeutic agent in many diseases. Our aim was to test the effect of maternal CBD in the intestine of an experimental model of GS. Pregnant rats were treated over 3 days with CBD (30 mg/kg) after the surgical induction of GS (day 18.5 of gestation) and compared to controls. Fetuses were divided into 4 groups: 1) control (C); 2) C+CBD (CCBD); 3) gastroschisis (G), and 4) G+CBD (GCBD). On day 21.5 of gestation, the fetuses were harvested and evaluated for: a) body weight (BW), intestinal weight (IW), and IW/BW ratio; b) histometric analysis of the intestinal wall; c) immunohistochemically analysis of inflammation (iNOS) and nitrite/nitrate level. BW: GCBD was lower than CCBD (P<0.005), IW and IW/BW ratio: GCBD was smaller than G (P<0.005), GCBD presented lower thickness in all parameters compared to G (P<0.005), iNOS and nitrite/nitrate were lower concentration in GCBD than to G (P<0.005). Maternal use of CBD had a beneficial effect on the intestinal loops of GS with decreased nitrite/nitrate and iNOS expression.


Subject(s)
Animals , Female , Pregnancy , Rats , Cannabidiol/therapeutic use , Gastroschisis/metabolism , Enteritis/prevention & control , Fetal Diseases/metabolism , Intestines/drug effects , Anti-Inflammatory Agents/therapeutic use , Immunohistochemistry , Rats, Sprague-Dawley , Gastroschisis/pathology , Disease Models, Animal , Nitric Oxide Synthase Type II/analysis , Fetal Diseases/pathology , Nitrates/metabolism , Nitrites/metabolism
4.
Braz. j. biol ; 75(4): 940-947, Nov. 2015. tab, graf
Article in English | LILACS | ID: lil-768214

ABSTRACT

Abstract Lignocellulose is the most abundant environmental component and a renewable organic resource in soil. There are some filamentous fungi which developed the ability to break down and use cellulose, hemicellulose and lignin as an energy source. The objective of this research was to analyze the effect of three nitrogen resources (ammonium sulfate, saltpetre, soybean) in the holocellulolitic activity of Lentinula edodes EF 50 using as substrate sawdust E. benthamii. An experimental design mixture was applied with repetition in the central point consisting of seven treatments (T) of equal concentrations of nitrogen in ammonium sulfate, potassium nitrate and soybean. The enzymatic activity of avicelase, carboxymetilcellulase, β-glucosidase, xylanases and manganese peroxidase was determined. The humidity, pH, water activity (aw) and qualitative analysis of mycelial growth in 8 times of cultivation were evaluated. The results showed negative effect on enzyme production in treatments with maximum concentration of ammonium sulfate and potassium nitrate. The treatments with cooked soybean flour expressed higher enzymatic activities in times of 3, 6 and 9 days of culture, except in the activity of manganese peroxidase. The highest production was observed in the treatment with ammonium sulfate, and soybean (83.86 UI.L–1) at 20 days of cultivation.


Resumo Lignocelulose é o componente mais abundante do meio ambiente e recurso orgânico renovável no solo. Alguns fungos filamentosos têm desenvolvido a habilidade de degradar e utilizar celulose, hemicelulose e lignina como fonte de energia. O objetivo deste trabalho foi analisar o efeito de três fontes de nitrogênio (sulfato de amônio, nitrato de potássio e farelo de soja) na atividade enzimática de Lentinula edodes EF 50 utilizando como substrato serragem de E. benthamii. Foi aplicado um planejamento experimental de mistura com três repetições no ponto central constituído de sete tratamentos (T) de iguais concentrações em nitrogênio de sulfato de amônia, nitrato de potássio e farinha de soja cozida. Foram determinadas a atividade enzimática da avicelase, carboximetilcelulase, β-glicosidase, xilanases e manganês peroxidase. Foram avaliados o teor de umidade, pH, atividade de água (aw) e análise qualitativa do crescimento micelial em 8 tempos de cultivo. Os resultados mostraram efeito negativo na produção das enzimas nos tratamentos com máxima concentração de sulfato de amônia e nitrato de potássio. Os tratamentos com farinha de soja cozida expressaram maiores atividades enzimáticas, nos tempos de 3, 6 e 9 dias de cultivo exceto na atividade do manganês peroxidase. A maior produção foi observada no tratamento com sulfato de amônia e farinha de soja cozida (83.86 UI.L–1) em 20 dias de cultivo.


Subject(s)
Biomass , Lignin/pharmacology , Nitrogen/metabolism , Shiitake Mushrooms/enzymology , Shiitake Mushrooms/growth & development , Ammonium Sulfate/metabolism , Eucalyptus/chemistry , Nitrates/metabolism , Potassium Compounds/metabolism , Soybeans/chemistry , Wood/analysis
5.
Indian J Exp Biol ; 2015 Mar; 53(3): 177-183
Article in English | IMSEAR | ID: sea-158412

ABSTRACT

We studied the influence of sucrose and nitrogen concentration on in vitro flowering and fruit setting in elongated shoots of Withania somnifera. BA (1.5 mg/l) and IAA (0.3 mg/l) on MS medium supplemented with 4% sucrose showed 67% of in vitro flower induction frequency, 9 flowers/shoot, 4 fruits/shoot and 11 seeds/fruit in elongated-shoots. Different concentrations of nitrogen sources (L-glutamine, adenine sulphate, ammonium nitrate, potassium nitrate and sodium nitrate 5-25 mg/l) were tested in combination with 4% sucrose and BA at 1.5 mg/l and IAA at 0.3 mg/l. Highest number of flowers (20 flowers/shoot; 2.2-fold) and fruits (16 fruits/shoot; 3.39-fold), fruit setting (12 seeds/fruit; 1.08-fold) at a higher frequency (88 %) were achieved on MS medium augmented with 15 mg/l adenine sulphate with same PGRs and sucrose concentration. The maximum production of withanolide A (0.68 mg/g DW) and withanolide B (0.77 mg/g DW) was recorded in in vitro fruits. Highest accumulation of withaferin A (2 mg/g DW) was quantified from in vitro flowers, whereas, it was low in in vitro fruits (0.49 mg/g DW withaferin A). However, withanone (0.23 mg/g DW) was found accumulated uniformly in both in vitro flowers and fruits compared to control.


Subject(s)
Adenine/metabolism , Adenine/pharmacology , Carbon/metabolism , Culture Media/chemistry , Culture Media/pharmacology , Flowers/chemistry , Flowers/growth & development , Fruit/chemistry , Fruit/growth & development , Germination/drug effects , Glutamine/metabolism , Glutamine/pharmacology , Hydroponics , Nitrates/metabolism , Nitrates/pharmacology , Nitrogen/metabolism , Plant Shoots/chemistry , Plant Shoots/metabolism , Sucrose/metabolism , Sucrose/pharmacology , Withania/chemistry , Withania/growth & development , Withania/metabolism , Withanolides/metabolism
6.
Indian J Exp Biol ; 2014 Dec; 52(12): 1159-1164
Article in English | IMSEAR | ID: sea-153806

ABSTRACT

The objective of this work was to evaluate the effect of using L-arginine during in vitro fertilization (IVF) on in vitro embryonic development using Bos taurus and Bos indicus semen. Effect of different concentrations (0, 1, 10 and 50 mM) of L-arginine, added to the IVF medium, was evaluated on the fertilization rate at 18 h post-fertilization (hpf), NO3-/NO2- production during IVF by the Griess colorimetric method (30 hpf), cleavage and blastocyst rates (on Day 2 and Day 7 of culture, respectively) and total blastocyst cell number (Day 7 of culture). The results reveal that the addition of 50 mM L-arginine to IVF medium, with either Bos taurus or Bos indicus spermatozoa, decreased the cleavage rate and blastocyst rate compared to the control group. Other concentrations did not affect embryo production. However, 1 mM L-arginine with Bos indicus semen increased the proportion of hatched blastocysts. These results indicate that high L-arginine concentrations may exhibit toxic effects on bovine gametes during in vitro fertilization.


Subject(s)
Animals , Arginine , Blastocyst/cytology , Blastocyst/drug effects , Blastocyst/metabolism , Cattle , Dose-Response Relationship, Drug , Embryo, Mammalian/cytology , Embryo, Mammalian/drug effects , Embryo, Mammalian/metabolism , Embryonic Development/drug effects , Female , Fertilization/drug effects , Fertilization in Vitro/drug effects , Male , Microscopy, Fluorescence , Nitrates/metabolism , Nitrites/metabolism , Spermatozoa/drug effects
7.
Indian J Exp Biol ; 2014 Apr; 52(4): 352-358
Article in English | IMSEAR | ID: sea-150366

ABSTRACT

Effect of salinity (0, 50, 100, 250, 500 and 750 mM NaCl) was observed on some important physiological parameters of nitrogen metabolism such as nitrate uptake, intracellular and extracellular ammonium status and activities of nitrogenase, nitrate reductase, nitrite reductase and glutamine synthetase among Frankia strains differing in their salt tolerance capacity. Nitrogenase activity closely followed the growth pattern with regular decline on NaCl supplementation. All the other enzymes showed optimum activity at 100 mM and declined further. Co-regulation of the nitrate uptake system and sequential enzyme activities plays a crucial role in governing the nitrogen status of strains during salt stress. HsIi10 experiencing minimum decline in enzyme activities and best possible nitrogen regulation under NaCl replete condition showed adequate nutritional management. Among all the strains, HsIi10 proved to be salt tolerant on account of above features while the salt sensitive strain HsIi8 lacked the ability to regulate various steps of nitrogen metabolism during salinity, and thus Frankia strain HsIi10 can potentially serve as a potential biofertilizer in the saline soil.


Subject(s)
Ammonia/metabolism , Frankia/enzymology , Frankia/metabolism , Glutamate-Ammonia Ligase/metabolism , Nitrates/metabolism , Nitrogen/metabolism , Nitrogenase/metabolism , Salinity , Salt Tolerance , Sodium Chloride/metabolism
8.
Electron. j. biotechnol ; 16(4): 12-12, July 2013. ilus, tab
Article in English | LILACS | ID: lil-684027

ABSTRACT

Background: L-glutamic acid, the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism acts as a precursor of γ-amino butyric acid (GABA). In the present study, culture condition for enhanced glutamic acid production by Lactobacillus plantarum MNZ was optimized and the influence of such conditions on GABA production was evaluated. Results: Results indicated that glutamic acid increased up to 3-fold (3.35) under the following condition: pH 4.5, temperature 37ºC, 12% (w/v) glucose and 0.7% (w/v) ammonium nitrate; whilst GABA production was enhanced up to 10-fold under the following condition: pH 4.5, temperature 37ºC, 6% (w/v) glucose and 0.7% (w/v) ammonium nitrate. Conclusions: This is the first report for dual biosynthesizing activities of a lactic acid bacterium for the production of glutamic acid and GABA. The results of this study can be further used for developing functional foods rich inglutamic acid and subsequently GABA as a bioactive compound.


Subject(s)
Glutamic Acid/biosynthesis , Lactobacillus plantarum/metabolism , gamma-Aminobutyric Acid/biosynthesis , Temperature , Chromatography, High Pressure Liquid , Glutamic Acid/analysis , Butyric Acid , Functional Food , Fermentation , Ammonium Compounds , gamma-Aminobutyric Acid/analysis , Glucose/analysis , Glucose/metabolism , Hydrogen-Ion Concentration , Nitrates/metabolism
9.
Yonsei Medical Journal ; : 1154-1158, 2012.
Article in English | WPRIM | ID: wpr-183499

ABSTRACT

PURPOSE: To investigate gastric juice nitrate/nitrite concentration according to mucosal surface pH extent (area) of gastric corpus intimately contacting the gastric juice. MATERIALS AND METHODS: We included ninety-nine patients with dyspepsia. To evaluate gastric mucosal surface pH and its extent, gastric chromosocpy was performed by spraying phenol red dye on the corpus mucosa and estimating the extent of area with color changed. Nitrate/nitrite concentrations and pH of gastric juice were measured by ELISA and pH meter, respectively. Silver staining was done to histologically confirm the presence of Helicobacter pylori. RESULTS: Intragastric nitrate/nitrite concentrations in patients, showing phenol red staining mucosa were higher than those of unstaining mucosa (p=0.001): the more extensive in the area of phenol red staining area of corpus, the higher gastric juice pH found (r=0.692, p<0.001). Furthermore, the intragastric nitrate/nitrite concentrations correlated positively with gastric juice pH (r=0.481, p<0.001). CONCLUSION: The changes of mucosal surface pH and its extent in gastric corpus might affect either pH or nitrate/nitrite level of gastric juice.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Dyspepsia/metabolism , Enzyme-Linked Immunosorbent Assay , Gastric Juice/metabolism , Gastric Mucosa/metabolism , Helicobacter pylori/isolation & purification , Hydrogen-Ion Concentration , Nitrates/metabolism , Nitrites/metabolism
10.
Experimental & Molecular Medicine ; : 524-532, 2010.
Article in English | WPRIM | ID: wpr-214627

ABSTRACT

Arginase competitively inhibits nitric oxide synthase (NOS) via use of the common substrate L-arginine. Arginase II has recently reported as a novel therapeutic target for the treatment of cardiovascular diseases such as atherosclerosis. Here, we demonstrate that piceatannol-3'-O-beta-D-glucopyranoside (PG), a potent component of stilbenes, inhibits the activity of arginase I and II prepared from mouse liver and kidney lysates, respectively, in a dose-dependent manner. In human umbilical vein endothelial cells, incubation of PG markedly blocked arginase activity and increased NOx production, as measured by Griess assay. The PG effect was associated with increase of eNOS dimer ratio, although the protein levels of arginase II or eNOS were not changed. Furthermore, isolated mice aortic rings treated with PG showed inhibited arginase activity that resulted in increased nitric oxide (NO) production upto 78%, as measured using 4-amino-5-methylamino-2',7'-difluorescein (DAF-FM) and a decreased superoxide anions up to 63%, as measured using dihydroethidine (DHE) in the intact endothelium. PG showed IC50 value of 11.22 microM and 11.06 microM against arginase I and II, respectively. PG as an arginase inhibitor, therefore, represents a novel molecule for the therapy of cardiovascular diseases derived from endothelial dysfunction and may be used for the design of pharmaceutical compounds.


Subject(s)
Animals , Humans , Mice , Aorta/drug effects , Arginase/antagonists & inhibitors , Dose-Response Relationship, Drug , Endothelial Cells/drug effects , Enzyme Activation/drug effects , Glucosides/chemistry , Mice, Inbred C57BL , Nitrates/metabolism , Nitric Oxide/biosynthesis , Nitric Oxide Synthase Type III/metabolism , Nitrites/metabolism , Reactive Oxygen Species/metabolism , Rheum/chemistry , Stilbenes/chemistry
11.
Arq. bras. endocrinol. metab ; 53(4): 399-408, jun. 2009. ilus
Article in Portuguese | LILACS | ID: lil-520763

ABSTRACT

O prejuízo no transporte de glicose estimulada por insulina no músculo constitui um defeito crucial para o estabelecimento da intolerância à glicose e do diabetes tipo 2. Por outro lado, é notório o conhecimento de que tanto o exercício aeróbio agudo quanto o crônico podem ter efeitos benéficos na ação da insulina em estados de resistência à insulina. No entanto, pouco se sabe sobre os efeitos moleculares pós-exercício sobre a sinalização da insulina no músculo esquelético. Assim, esta revisãoapresenta novos entendimentos sobre os mecanismos por meio dos quais o exercício agudo restaura a sensibilidade à insulina, com destaque ao importante papel que proteínas inflamatórias e a S-nitrosação possuem sobre a regulação de proteínas da via de sinalização da insulina no músculo esquelético.


Insulin resistance of skeletal muscle glucose transport is a key-defect for the development of impaired glucose tolerance and type 2 diabetes. However, it is known that both an acute bout of exercise and chronic endurance exercise training can bring beneficial effects on insulin action in insulin-resistant states. However, little is currently known about the molecular effects of acute exercise on muscle insulin signaling in the post-exercise state in insulin-resistant organisms. This review provides new insight into the mechanism through which acute exercise restores insulin sensitivity, highlighting an important role for inflammatory proteins and S-nitrosation in the regulation of insulin signaling proteins in skeletal muscle.


Subject(s)
Humans , Exercise/physiology , Insulin Resistance/physiology , Muscle, Skeletal/metabolism , Signal Transduction/physiology , Glucose/metabolism , Inflammation/metabolism , Insulin Receptor Substrate Proteins/metabolism , Nitrosation , Nitrates/metabolism
12.
J Environ Biol ; 2007 Apr; 28(2): 303-6
Article in English | IMSEAR | ID: sea-113277

ABSTRACT

The effect of mercury (Hg) on the biochemical parameters of Lycopersicon esculentum Mill leaf was studied. Application of mercuric chloride in varying concentrations (0.5, 1.0, 1.5 and 2.0 mM HgCl2 kg(-1) sand) caused significant reduction that went up to 89% and 72% chlorophyll a and chlorophyll b contents respectively (at flowering stage), 69% in carotenoid content, 64% in total soluble protein content and 91% in nitrate reductase activity (all at post-flowering stage). The amounts of nitrate and proline increased maximally (151% and 143% respectively) at the flowering stage, whereas total soluble sugar enhanced by 57% at the post-flowering stage. Changes observed in most of the parameters, were concentration dependent. Such studies seem to be able to discover suitable bioindicators of heavy metal pollution.


Subject(s)
Carbohydrate Metabolism/drug effects , Carotenoids/metabolism , Chlorophyll/metabolism , Solanum lycopersicum/drug effects , Mercury/toxicity , Nitrate Reductase/metabolism , Nitrates/metabolism , Plant Leaves/drug effects , Plant Proteins/metabolism , Proline/metabolism , Soil Pollutants/toxicity
13.
Genet. mol. res. (Online) ; 6(3): 634-642, 2007. ilus, tab
Article in English | LILACS | ID: lil-498907

ABSTRACT

The heterokaryotic and vegetative diploid phases of Colletotrichum lindemuthianum are described using nutritional and biochemical markers. Nitrate non-utilizing mutants (nit), derived from R2047, R89, R73, R65, and R23 isolates, were paired in all possible combinations to obtain heterokaryons. Although pairings R2047/R89, R2047/R73, R65/R73, and R73/R23 showed complete vegetative incompatibility, prototrophic heterokaryons were obtained from pairings R2047/R65, R2047/R23, R65/R89, R65/R23, R73/R89, R89/R23, R2047/R2047, R65/R65, R89/R89, R73/R73, and R23/R23. Heterokaryons gave rise to spontaneous mitotic segregants which carried markers corresponding to one or the other of the parental strains. Heterokaryons spontaneously produced prototrophic fast-growing sectors too, characterized as diploid segregants. Diploids would be expected to yield auxotrophic segregants following haploidization in basal medium or in the presence of benomyl. Parental haploid segregants were in fact recovered from diploid colonies growing in basal medium and basal medium containing the haploidizing agent. Although barriers to the formation of heterokaryons in some crosses were detected, the results demonstrate the occurrence of parasexuality among vegetative compatible mutants of C. lindemuthianum.


Subject(s)
Chromosome Segregation , Colletotrichum/cytology , Diploidy , Nitrates/metabolism , Phaseolus/microbiology , Colletotrichum/enzymology , Esterases/metabolism , Haploidy , Hyphae/cytology , Mutation/genetics , Cell Nucleus/metabolism , Phenotype
14.
Article in English | IMSEAR | ID: sea-114091

ABSTRACT

The performance of a laboratory-scale Sequencing Batch Reactor (SBR) has been studied in aerobic-anoxic sequence for simultaneous organic carbon and nitrogen removal. The reactor was operated under three different variations of aerobic-anoxic sequence, viz. 4+4, 5+3 and 3+5 hours with input solutions of soluble COD (SCOD) level 1000 +/- 100 mg/L and initial ammonia nitrogen of 40 and 90 mg/L. It has been observed that 85 to 92% of SCOD removal would be possible at the end of 8.0 hour of overall reaction period, irrespective of the length of the aerobic react period. In the case of 4+4 hour operating cycle, reasonable degree of nitrification (88-100%) and denitrification (73-75%), along with 91-94% of organic carbon removal have been achieved, which has been considered to be the optimum performance of the reactor.


Subject(s)
Aerobiosis , Ammonia/metabolism , Anaerobiosis , Bioreactors , Carbon/metabolism , Laboratories , Nitrates/metabolism , Nitrites/metabolism , Nitrogen/metabolism , Oxidation-Reduction , Pilot Projects , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/metabolism
15.
Article in English | IMSEAR | ID: sea-114040

ABSTRACT

The present study was undertaken to observe the effect of biological denitrification process on water quality parameters. The results obtained in the present investigations show that the value of pH and alkalinity was increased due to generation of alkalinity during biological denitrification process. The obtained value of the DO in the treated water was found lower than the supplied water, which indicates, DO was consumed by the bacterium. The COD of the treated water was nil, which shows that the organics have been consumed by the bacterium during the denitrification process. The biological reduction of nitrate-nitrogen (from 50.79 mg/L to 0.57 mg/L) was found to be lower than the tolerance limit prescribed by WHO without changing the water quality.


Subject(s)
Bioreactors , Hydrogen-Ion Concentration , Nitrates/metabolism , Oxidation-Reduction , Oxygen/analysis , Pseudomonas stutzeri/metabolism , Temperature , Water Pollutants, Chemical/metabolism , Water Purification/methods
16.
Article in English | IMSEAR | ID: sea-23086

ABSTRACT

BACKGROUND & OBJECTIVES: Rapid susceptibility testing of Mycobacterium tuberculosis strains is imperative for therapy selection but traditional drug susceptibility tests take weeks or are expensive. In this study we evaluated nitrate reductase assay which utilizes the detection of nitrate reduction as an indication of growth and therefore results can be obtained faster than by visual detection of colonies. METHODS: One hundred clinical isolates of M. tuberculosis were tested for four first line antitubercular drugs by nitrate reductase assay (NRA) and were compared with standard proportion method. The bacteria were inoculated on Lowenstein-Jensen (LJ) medium with primary antitubercular drugs and potassium nitrate was incorporated. After incubation for 7- 14 days, nitrate reduction indicating growth could be detected by colour change when reagents were added. RESULTS: Resistance of isolates as determined by both methods for isoniazid, rifampicin, streptomycin and ethambutol was 32, 35, 62 and 15 per cent respectively. Agreement between NRA and proportion method was 99 per cent for isoniazid and ethambutol. Complete agreement (100%) was found for rifampicin and streptomycin. Results were available in 7-14 days by NRA as compared to proportion method which takes 4-6 wk. INTERPRETATION & CONCLUSION: Nitrate reductase assay is a rapid and inexpensive method for susceptibility testing of M. tuberculosis for primary antitubercular drugs and could be an appropriate alternative to existing methods, particularly in resource-poor settings.


Subject(s)
Antitubercular Agents/pharmacology , Humans , Microbial Sensitivity Tests/methods , Mycobacterium tuberculosis/drug effects , Nitrate Reductase , Nitrate Reductases/metabolism , Nitrates/metabolism , Reproducibility of Results , Tuberculosis/drug therapy
17.
Arq. gastroenterol ; 40(1): 16-19, Jan.-Mar. 2003. tab, graf
Article in Portuguese | LILACS | ID: lil-347605

ABSTRACT

INTRODUÇAO: O risco de desenvolvimento de carcinoma esofágico em portadores de megaesôfago é 33 vezes superior ao da populaçäo em geral. Possível explicaçäo para este fenômeno poderia estar relacionada à produçäo de compostos N-nitrosos na luz do órgäo, a partir da transformaçäo de nitratos da dieta em nitritos, mediada por bactérias em suspensäo no líquido de estase e com o contato crônico destes carcinógenos com a mucosa esofágica. OBJETIVO: Analisar a microbiota esofágica em pacientes portadores de megaesôfago de etiologia chagásica, com especial atençäo para a presença de bactérias com capacidade de reduçäo de nitratos. CASUíSTICA: Foram estudados prospectivamente 15 pacientes portadores de megaesôfago chagásico com idades variando de 28 a 73 anos, sendo 9 do sexo feminino e 6 do sexo masculino, que foram divididos em 3 grupos iguais de 5, de acordo com o grau de dilataçäo do esôfago, segundo a classificaçäo de Rezende et al. (Grau I, Grau II e Grau III). MÉTODO: A coleta do líquido de estase para estudo microbiológico era realizada através de sonda de Levine nº 14, que era passada pela boca, por dentro de uma cânula de intubaçäo orotraqueal nº 7,5, mantendo-se sua extremidade escondida, a fim de evitar sua contaminaçäo. RESULTADOS: Foram obtidas 93,3 por cento de culturas positivas com grande variedade de microrganismos e predomínio de aeróbios Gram-positivos e anaeróbios. As concentrações de microrganismos foram tanto maiores, quanto maior o grau de dilataçäo do esôfago. Entre os microrganismos encontrados, o Staphylococcus sp, Corynebacterium sp, Peptostreptococcus sp e a Veillonella sp foram aqueles identificados como tendo a capacidade de reduçäo de nitratos a nitritos. CONCLUSÄO: No megaesôfago chagásico há bactérias na luz do órgäo com capacidade de reduçäo de nitratos da dieta, passo importante na produçäo de compostos N-nitrosos.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Chagas Disease/microbiology , Esophageal Achalasia/microbiology , Esophageal Neoplasms/microbiology , Colony Count, Microbial , Chagas Disease/complications , Dilatation, Pathologic , Esophageal Achalasia/etiology , Esophagus/microbiology , Esophagus/pathology , Nitrates/metabolism , Nitroso Compounds/metabolism , Prospective Studies
18.
Journal of Korean Medical Science ; : 489-493, 2003.
Article in English | WPRIM | ID: wpr-156014

ABSTRACT

The monitoring of airway inflammation has assessed in bronchial asthma directly by sputum examination, and indirectly by measurements in peripheral blood. To investigate the diagnostic value of these two methods, we compared nitric oxide (NO) metabolites, eosinophils, and eosinophil cationic protein (ECP) in sputum and blood in patients with asthma and control subjects. Sputum and serum were obtained from fifteen patients with asthma, and then were examined before anti-asthma treatment, including steroid preparations. ECP was measured by fluoroimmunoassay. NO metabolites were assayed by using modified Griess reaction. Asthmatic patients, compared with control subjects, had significantly higher level of NO metabolites, higher proportion of eosinophils, and higher levels of ECP in sputum. Asthmatic patients, compared with control subjects, however, had significantly higher number of eosinophils, and were at higher levels of ECP in blood. FEV1, FEV1 /FVC was negatively correlated with sputum eosinophils. The area under receiver operating characteristic(ROC) curve showed that eosinophils in sputum are significantly accurate markers than NO metabolites in sputum and blood. These findings suggest that the proportion of eosinophils in sputum have more accurate diagnostic marker of asthmatic airway inflammation than NO metabolites in sputum in differentiating asthmatic patients from control subjects.


Subject(s)
Adult , Female , Humans , Male , Area Under Curve , Asthma/blood , Blood Proteins/metabolism , Comparative Study , Eosinophils/metabolism , Fluoroimmunoassay , Inflammation , Nitrates/metabolism , Nitric Oxide/blood , Nitrites/metabolism , ROC Curve , Ribonucleases/blood , Sputum/metabolism
19.
Indian J Exp Biol ; 2002 May; 40(5): 594-9
Article in English | IMSEAR | ID: sea-56772

ABSTRACT

Various physiological and biochemical process like growth, NO3- -uptake, nitrate reductase, glutamine synthetase and ATPases (Mg2+ and Ca2+ dependent) in the cyanobacterium Anabaena 7120 were observed under iron stress. Growth was found to be maximum in 50 microM Fe3+ added cells however, 20 microM Fe3+ (the Fe3+ concentration generally used for routine culturing of cyanobacterial cell in Chu 10 medium) incubation resulted in lower growth. Fe3+ starvation on the other hand showed very poor growth up to 4th day but once the growth started it reached at significant level on 7th day. Higher Fe3+ concentration reflected reduced growth with lethality at 500 microM Fe3+. Chlorophyll a fluorescence under Fe3+ stress reflected almost the similar results as in case of growth. However, the pigment was found to be more sensitive as compared to protein under Fe3+ stress. Similar results have been observed in case of NO3-uptake with only 80% reduction in nutrient uptake in 500 microM Fe3+ incubated cells. Nitrate reductase activity was lower in Fe3+ starved cells as compared to significant enzyme activity in 20 and 50 microM Fe3+ incubated cells. Similar to nitrate reductase, glutamine synthetase also showed maximum level in 50 microM Fe3+ added cells, however, higher Fe3+ concentration (300-500 microM ) resulted in reduced enzymatic activity. Glutamine synthetase activity was less sensitivity as compared to nitrate reductase activity under Fe3+ stress. ATPase (Mg2+ and Ca2+ dependent) always showed higher level with increasing Fe3+ concentration.


Subject(s)
Adenosine Triphosphatases/metabolism , Anabaena/enzymology , Glutamate-Ammonia Ligase/metabolism , Iron/pharmacology , Nitrate Reductase , Nitrate Reductases/metabolism , Nitrates/metabolism , Spectrometry, Fluorescence
20.
J Environ Biol ; 2001 Jul; 22(3): 153-62
Article in English | IMSEAR | ID: sea-113194

ABSTRACT

Garden soil samples polluted with crude petroleum were bioremediated by inorganic nutrient monitoring with appropriate adjustment and inoculation with crude oil-adapted strain of Pseudomonasputida (PP) isolated from oil-impacted soils. Soil samples without PP inoculation served as the control samples to compare the abilities of the native soil microflora with the adapted PP strain in biodegrading crude oil pollutant. In the experimental samples, oil concentration and all the inorganic nutrient sources tested decreased more rapidly with a proportional increase in the population densities of both PP and the native soil microflora than were observed in the control samples. This trend was particularly strong for PO4(3-) and NO3- which eventually became limiting both in all the experimental samples and in some control samples. Inoculation of crude oil-impacted agricultural soils by oil -adapted PP strain with nutrient monitoring and adjustment can be effective as bioremediation methods of agricultural land upon pollution with petroleum or petroleum products.


Subject(s)
Adaptation, Physiological , Agriculture , Biodegradation, Environmental , Nitrates/metabolism , Petroleum/metabolism , Phosphates/metabolism , Pseudomonas putida/physiology , Soil Microbiology , Soil Pollutants/metabolism
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