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1.
Medicina (B.Aires) ; 80(2): 157-161, abr. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1125057

ABSTRACT

Un tercio de la población mundial tiene niveles anormalmente altos de presión arterial, hipertensión, responsable de casi el 50% de las muertes por accidente cerebrovascular y enfermedad coronaria. La sensibilidad a la sal es un factor de riesgo para la morbilidad y mortalidad cardiovascular y también para otras enfermedades. En estudios previos describimos un modelo de hipertensión sal sensible (HSS) en ratas Wistar ovariectomizadas (oVx) adultas. Las ratas oVx son normotensas con ingesta normal de sal (NS, 0.24% de NaCl), pero desarrollan un perfil de HSS con una ingesta elevada de sal (HS, 1% de NaCl). En los estudios en riñón encontramos que el circuito receptor D1 de dopamina, citocromo P450 4A y Na+, K+-ATPasa está alterado por la ausencia de hormonas ováricas, lo que se asocia a menor excreción de sodio e hipertensión arterial. La ingesta HS en ratas oVx también promueve cambios en la expresión de proteínas relacionadas con el transporte de sodio en células mononucleares de sangre periférica, principalmente linfocitos periféricos. Por lo tanto, el transporte de sodio se modifica en varios niveles de la fisiología normal. En estudios recientes observamos que el estradiol aumenta la proliferación y diferenciación de células epiteliales en cultivos de corteza renal humana. Sensibilidad a la sal, inmunidad adaptativa, presión arterial y proliferación de células epiteliales en riñón son fenómenos de gran importancia biológica regulados por estradiol.


Female sex hormones participate in the regulation of blood pressure and renal epithelial proliferation, effects not related to their reproductive function. About one-third of the world's population has abnormally high levels of blood pressure, hypertension, which is responsible for almost 50% of deaths from stroke and coronary heart disease. Salt sensitivity is a risk factor for cardiovascular morbidity and mortality and other diseases as well. We reported a model of salt sensitive hypertension in adult ovariectomized (oVx) Wistar rats. oVx rats are normotensive under normal salt intake (NS, 0.24% NaCl), but upon a high salt intake (HS, 1% NaCl) oVx rats developed a blood pressure profile of salt-sensitive hypertension. Our studies on kidney molecules related to sodium balance found that the circuit dopamine D1-like receptor, cytochrome P450 4A and Na+, K+-ATPase is altered by the absence of ovary hormones which is accompanied by a reduced ability to excrete sodium. In oVx rats HS intake also promotes changes in the expression of proteins related to sodium transport in peripheral blood mononuclear cells, mainly peripheral lymphocytes. Therefore, sodium transport is modified at several levels of normal physiology. Lately, we described that estradiol increases the rate of renal epithelial cell proliferation in primary cultures developed from human renal cortex. Thus, salt sensitivity, adaptive immunity, blood pressure and renal cell proliferation are complex biological responses regulated by female sex hormones.


Subject(s)
Humans , Animals , Female , Rats , Sodium Chloride/metabolism , Estradiol/metabolism , Hypertension/metabolism , Kidney/metabolism , Blood Pressure , Sodium Chloride/adverse effects , Rats, Wistar , Sodium-Potassium-Exchanging ATPase , Cell Proliferation , Hypertension/physiopathology
2.
Braz. j. microbiol ; 49(4): 685-694, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-974282

ABSTRACT

ABSTRACT To mitigate the deleterious effects of abiotic stress, the use of plant growth-promoting bacteria along with diazotrophic bacteria has been increasing. The objectives of this study were to investigate the key enzymes related to nitrogen and carbon metabolism in the biological nitrogen fixation process and to elucidate the activities of these enzymes by the synergistic interaction between Bradyrhizobium and plant growth-promoting bacteria in the absence and presence of salt stress. Cowpea plants were cultivated under axenic conditions, inoculated with Bradyrhizobium and co-inoculated with Bradyrhizobium sp. and Actinomadura sp., Bradyrhizobium sp. and Bacillus sp., Bradyrhizobium sp. and Paenibacillus graminis, and Bradyrhizobium sp. and Streptomycessp.; the plants were also maintained in the absence (control) and presence of salt stress (50 mmolL-1 NaCl). Salinity reduced the amino acids, free ammonia, ureides, proteins and total nitrogen content in nodules and increased the levels of sucrose and soluble sugars. The co-inoculations responded differently to the activity of glutamine synthetase enzymes under salt stress, as well as glutamate synthase, glutamate dehydrogenase aminating, and acid invertase in the control and salt stress. Considering the development conditions of this experiment, co-inoculation with Bradyrhizobium sp. and Bacillus sp. in cowpea provided better symbiotic performance, mitigating the deleterious effects of salt stress.


Subject(s)
Carbon/metabolism , Sodium Chloride/metabolism , Vigna/metabolism , Nitrogen/metabolism , Soil Microbiology , Sodium Chloride/analysis , Actinobacteria/physiology , Plant Roots/growth & development , Plant Roots/metabolism , Plant Roots/microbiology , Bradyrhizobium/physiology , Agricultural Inoculants/physiology , Vigna/growth & development , Vigna/microbiology , Amino Acids/metabolism , Nitrogen Fixation
3.
Braz. j. microbiol ; 49(3): 503-512, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951798

ABSTRACT

Abstract Erythrina velutina ("mulungu") is a legume tree from Caatinga that associates with rhizobia but the diversity and symbiotic ability of "mulungu" rhizobia are poorly understood. The aim of this study was to characterize "mulungu" rhizobia from Caatinga. Bacteria were obteined from Serra Talhada and Caruaru in Caatinga under natural regeneration. The bacteria were evaluated to the amplification of nifH and nodC and to metabolic characteristics. Ten selected bacteria identified by 16S rRNA sequences. They were tested in vitro to NaCl and temperature tolerance, auxin production and calcium phosphate solubilization. The symbiotic ability were assessed in an greenhouse experiment. A total of 32 bacteria were obtained and 17 amplified both symbiotic genes. The bacteria showed a high variable metabolic profile. Bradyrhizobium (6), Rhizobium (3) and Paraburkholderia (1) were identified, differing from their geographic origin. The isolates grew up to 45 °C to 0.51 mol L-1 of NaCl. Bacteria which produced more auxin in the medium with l-tryptophan and two Rhizobium and one Bradyrhizobium were phosphate solubilizers. All bacteria nodulated and ESA 90 (Rhizobium sp.) plus ESA 96 (Paraburkholderia sp.) were more efficient symbiotically. Diverse and efficient rhizobia inhabit the soils of Caatinga dry forests, with the bacterial differentiation by the sampling sites.


Subject(s)
Rhizobium/physiology , Symbiosis , Bradyrhizobium/physiology , Erythrina/microbiology , Phenotype , Phylogeny , Rhizobium/isolation & purification , Rhizobium/genetics , DNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Sodium Chloride/metabolism , Forests , Bradyrhizobium/isolation & purification , Bradyrhizobium/genetics , Erythrina/physiology
4.
Braz. j. microbiol ; 49(3): 513-521, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951812

ABSTRACT

Abstract Soil salinity is an important abiotic stress worldwide, and salt-induced oxidative stress can have detrimental effects on the biological nitrogen fixation. We hypothesized that co-inoculation of cowpea plants with Bradyrhizobium and plant growth-promoting bacteria would minimize the deleterious effects of salt stress via the induction of enzymatic and non-enzymatic antioxidative protection. To test our hypothesis, cowpea seeds were inoculated with Bradyrhizobium or co-inoculated with Bradyrhizobium and plant growth-promoting bacteria and then submitted to salt stress. Afterward, the cowpea nodules were collected, and the levels of hydrogen peroxide; lipid peroxidation; total, reduced and oxidized forms of ascorbate and glutathione; and superoxide dismutase, catalase and phenol peroxidase activities were evaluated. The sodium and potassium ion concentrations were measured in shoot samples. Cowpea plants did not present significant differences in sodium and potassium levels when grown under non-saline conditions, but sodium content was strongly increased under salt stress conditions. Under non-saline and salt stress conditions, plants co-inoculated with Bradyrhizobium and Actinomadura or co-inoculated with Bradyrhizobium and Paenibacillus graminis showed lower hydrogen peroxide content in their nodules, whereas lipid peroxidation was increased by 31% in plants that were subjected to salt stress. Furthermore, cowpea nodules co-inoculated with Bradyrhizobium and plant growth-promoting bacteria and exposed to salt stress displayed significant alterations in the total, reduced and oxidized forms of ascorbate and glutathione. Inoculation with Bradyrhizobium and plant growth-promoting bacteria induced increased superoxide dismutase, catalase and phenol peroxidase activities in the nodules of cowpea plants exposed to salt stress. The catalase activity in plants co-inoculated with Bradyrhizobium and Streptomyces was 55% greater than in plants inoculated with Bradyrhizobium alone, and this value was remarkably greater than that in the other treatments. These results reinforce the beneficial effects of plant growth-promoting bacteria on the antioxidant system that detoxifies reactive oxygen species. We concluded that the combination of Bradyrhizobium and plant growth-promoting bacteria induces positive responses for coping with salt-induced oxidative stress in cowpea nodules, mainly in plants co-inoculated with Bradyrhizobium and P. graminis or co-inoculated with Bradyrhizobium and Bacillus.


Subject(s)
Sodium Chloride/metabolism , Bradyrhizobium/physiology , Agricultural Inoculants/physiology , Vigna/microbiology , Antioxidants/metabolism , Plant Proteins/metabolism , Stress, Physiological , Superoxide Dismutase/metabolism , Lipid Peroxidation , Catalase/metabolism , Peroxidase/metabolism , Oxidative Stress , Salinity , Vigna/growth & development , Vigna/metabolism , Glutathione/metabolism
5.
Braz. j. microbiol ; 49(1): 7-9, Jan.-Mar. 2018.
Article in English | LILACS | ID: biblio-889192

ABSTRACT

ABSTRACT In this report, we present a draft genome of 2,886,173 bp of an Exiguobacterium aurantiacum strain PN47 isolate from the sediment of a saline pond named "Salar del Huasco" in the Altiplano in the North of Chile. Strain PN47 encodes adaptive characteristics enabling survival in extreme environmental conditions of high heavy metal and salt concentrations and high alkalinity.


Subject(s)
Bacillaceae/isolation & purification , Bacillaceae/genetics , Ponds/microbiology , Genome, Bacterial , Phylogeny , Bacillaceae/classification , Bacillaceae/metabolism , DNA, Bacterial/genetics , Base Sequence , Sodium Chloride/analysis , Sodium Chloride/metabolism , Ponds/chemistry , Chile , Metals, Heavy/analysis , Metals, Heavy/metabolism
6.
Braz. j. microbiol ; 49(supl.1): 236-245, 2018. graf
Article in English | LILACS | ID: biblio-974331

ABSTRACT

ABSTRACT Salinity and alkalinity are major abiotic stresses that limit growth and development of poplar. We investigated biocontrol potential of saline- and alkaline-tolerant mutants of Trichoderma asperellum to mediate the effects of salinity or alkalinity stresses on Populus davidiana × P. alba var. pyramidalis (PdPap poplar) seedlings. A T-DNA insertion mutant library of T. asperellum was constructed using an Agrobacterium tumefaciens mediated transformation system; this process yielded sixty five positive transformants (T1-T65). The salinity tolerant mutant, T59, grew in Potato Dextrose Agar (PDA) containing up to 10% (1709.40 mM) NaCl. Under NaCl-rich conditions, T59 was most effective in inhibiting Alternaria alternata (52.00%). The alkalinity tolerant mutants, T3 and T5, grew in PDA containing up to 0.4% (47.62 mM) NaHCO3. The ability of the T3 and T5 mutants to inhibit Fusarium oxysporum declined as NaHCO3 concentrations increased. NaHCO3 tolerance of the PdPap seedlings improved following treatment with the spores of the WT, T3, and T5 strains. The salinity tolerant mutant (T59) and two alkalinity tolerant mutants (T3 and T5) generated in this study can be applied to decrease the incidence of pathogenic fungi infection under saline or alkaline stress.


Subject(s)
Plant Diseases/microbiology , Trichoderma/physiology , Sodium Chloride/metabolism , Populus/growth & development , Alkalies/metabolism , Alternaria/physiology , Antibiosis , Plant Diseases/prevention & control , Stress, Physiological , Trichoderma/genetics , Populus/microbiology , Seedlings/growth & development , Seedlings/microbiology
7.
Electron. j. biotechnol ; 27: 80-83, May. 2017. ilus, graf
Article in English | LILACS | ID: biblio-1010415

ABSTRACT

Background: A protocol for the micropropagation of the grape (Vitis vinifera L.) cultivar 'Monastrell' was developed. Initial plant material was obtained from the sanitary selection of grapevine plants performed by real-time RT-PCR to confirm the absence of Grapevine fanleaf virus, Arabis mosaic virus, Grapevine leafroll-associated virus 1, Grapevine leafroll-associated virus 3, and Grapevine fleck virus. Results: The effects of the salt composition (comparing Lloyd and McCown woody plant medium and Murashige and Skoog medium 1/2 macronutrients) and the growth regulator benzylaminopurine (BAP), at 0 and 8.9 µM, on plant propagation were evaluated using nodes as explants. The most efficient procedure consisted of bud induction in the medium with Lloyd and McCown woody plant salts and 8.9 µM BAP for 30 d along with elongation in cytokinin-free medium for 60 d, which gave 22 nodes/explant (174 plants/initial plant). A second cycle of propagation in a medium without BAP for another 60 d could give approximately 10,000 nodes, which can be obtained after an additional 2 months of culture. All plants acclimatized after the second cycle of multiplication were successfully transferred to soil. Conclusion: We developed an optimal protocol for V. vinifera cv. 'Monastrell' micropropagation, the first described for this cultivar.


Subject(s)
Vitis/growth & development , Purines/metabolism , Benzyl Compounds/metabolism , In Vitro Techniques , Sodium Chloride/metabolism , Vitis/virology , Real-Time Polymerase Chain Reaction , Acclimatization
8.
Braz. j. microbiol ; 47(1): 85-95, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775117

ABSTRACT

Abstract The main objective of the present study was to isolate and characterize actinomycetes for their plant growth-promotion in chickpea. A total of 89 actinomycetes were screened for their antagonism against fungal pathogens of chickpea by dual culture and metabolite production assays. Four most promising actinomycetes were evaluated for their physiological and plant growth-promotion properties under in vitro and in vivo conditions. All the isolates exhibited good growth at temperatures from 20 °C to 40 °C, pH range of 7–11 and NaCl concentrations up to 8%. These were also found highly tolerant to Bavistin, slightly tolerant to Thiram and Captan (except VAI-7 and VAI-40) but susceptible to Benlate and Ridomil at field application levels and were found to produce siderophore, cellulase, lipase, protease, chitinase (except VAI-40), hydrocyanic acid (except VAI-7 and VAI-40), indole acetic acid and β-1,3-glucanase. When the four actinomycetes were evaluated for their plant growth-promotion properties under field conditions on chickpea, all exhibited increase in nodule number, shoot weight and yield. The actinomycetes treated plots enhanced total N, available P and organic C over the un-inoculated control. The scanning electron microscope studies exhibited extensive colonization by actinomycetes on the root surface of chickpea. The expression profiles for indole acetic acid, siderophore and β-1,3-glucanase genes exhibited up-regulation for all three traits and in all four isolates. The actinomycetes were identified as Streptomyces but different species in the 16S rDNA analysis. It was concluded that the selected actinomycetes have good plant growth-promotion and biocontrol potentials on chickpea.


Subject(s)
Actinobacteria/growth & development , Cicer/growth & development , Soil Microbiology , Actinobacteria/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Molecular Sequence Data , Phylogeny , Plant Growth Regulators/metabolism , Rhizosphere , /genetics , Sequence Analysis, DNA , Soil , Sodium Chloride/metabolism , Temperature
9.
Braz. j. microbiol ; 47(1): 1-9, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775132

ABSTRACT

Abstract This study was conducted to isolate an acid-producing, alkaliphilic bacterium to reduce the alkalinity of cement industry waste (cement kiln dust). Gram-positive isolate KG1 grew well at pH values of 6–12, temperatures of 28–50 °C, and NaCl concentrations of 0–16% and thus was further screened for its potential to reduce the pH of an alkaline medium. Phenotypic characteristics of the KG1 isolate were consistent with those of the genus Bacillus, and the highest level of 16S rRNA gene sequence similarity was found with Bacillus halodurans strain DSM 497 (94.7%). On the basis of its phenotypic characteristics and genotypic distinctiveness from other phylogenetic neighbors belonging to alkaliphilic Bacillus species, the isolated strain was designated B. halodurans strain KG1, with GenBank accession number JQ307184 (= NCIM 5439). Isolate KG1 reduced the alkalinity (by 83.64%) and the chloride content (by 86.96%) of cement kiln dust and showed a potential to be used in the cement industry for a variety of applications.


Subject(s)
Bacillus/growth & development , Bacillus/metabolism , Biotechnology/methods , Industrial Waste , Waste Management/methods , Bacterial Typing Techniques , Bacillus/classification , Bacillus/isolation & purification , Cluster Analysis , Construction Materials , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , Temperature
10.
Braz. j. microbiol ; 46(4): 1269-1277, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769645

ABSTRACT

Abstract A thermohalophilic fungus, Aspergillus terreus AUMC 10138, isolated from the Wadi El-Natrun soda lakes in northern Egypt was exposed successively to gamma and UV-radiation (physical mutagens) and ethyl methan-sulfonate (EMS; chemical mutagen) to enhance alkaline cellulase production under solid state fermentation (SSF) conditions. The effects of different carbon sources, initial moisture, incubation temperature, initial pH, incubation period, inoculum levels and different concentrations of NaCl on production of alkaline filter paper activity (FPase), carboxymethyl cellulase (CMCase) and β-glucosidase by the wild-type and mutant strains of A. terreus were evaluated under SSF. The optimum conditions for maximum production of FPase, CMCase and β-glucosidase were found to be the corn stover: moisture ratio of 1:3(w/v), temperature 45 °C, pH range, 9.0–11.0, and fermentation for 4, 4 and 7 day, respectively. Inoculum levels of 30% for β-glucosidase and 40% for FPase, CMCase gave the higher cellulase production by the wild-type and mutant strains, respectively. Higher production of all three enzymes was obtained at a 5% NaCl. Under the optimized conditions, the mutant strain A. terreus M-17 produced FPase (729 U/g), CMCase (1,783 U/g), and β-glucosidase (342 U/g), which is, 1.85, 1.97 and 2.31-fold higher than the wild-type strain. Our results confirmed that mutant strain M-17 could be a promising alkaline cellulase enzyme producer employing lignocellulosics especially corn stover.


Subject(s)
Aspergillus/enzymology , Aspergillus/metabolism , Cellulases/metabolism , Mutagenesis , Zea mays/metabolism , Aspergillus/drug effects , Aspergillus/radiation effects , Culture Media/chemistry , Egypt , Ethyl Methanesulfonate , Hydrogen-Ion Concentration , Lakes/microbiology , Microbiological Techniques , Sodium Chloride/metabolism , Temperature , Ultraviolet Rays
11.
Braz. j. microbiol ; 46(4): 1193-1199, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769649

ABSTRACT

Abstract The viability of Lactobacillus bulgaricus in freeze-drying is of significant commercial interest to dairy industries. In the study, L.bulgaricus demonstrated a significantly improved (p < 0.05) survival rate during freeze-drying when subjected to a pre-stressed period under the conditions of 2% (w/v) NaCl for 2 h in the late growth phase. The main energy source for the life activity of lactic acid bacteria is related to the glycolytic pathway. To investigate the phenomenon of this stress-related viability improvement in L. bulgaricus, the activities and corresponding genes of key enzymes in glycolysis during 2% NaCl stress were studied. NaCl stress significantly enhanced (p < 0.05) glucose utilization. The activities of glycolytic enzymes (phosphofructokinase, pyruvate kinase, and lactate dehydrogenase) decreased during freeze-drying, and NaCl stress were found to improve activities of these enzymes before and after freeze-drying. However, a transcriptional analysis of the corresponding genes suggested that the effect of NaCl stress on the expression of the pfk2 gene was not obvious. The increased survival of freeze-dried cells of L. bulgaricus under NaCl stress might be due to changes in only the activity or translation level of these enzymes in different environmental conditions but have no relation to their mRNA transcription level.


Subject(s)
Enzymes/metabolism , Freeze Drying , Lactobacillus/drug effects , Lactobacillus/radiation effects , Sodium Chloride/metabolism , Gene Expression Profiling , Glycolysis/drug effects , Glycolysis/radiation effects , Lactobacillus/enzymology , Lactobacillus/physiology , Microbial Viability/drug effects , Microbial Viability/radiation effects
12.
J. pediatr. (Rio J.) ; 91(5): 499-505, Sept.-Oct. 2015. tab, graf
Article in English | LILACS | ID: lil-766172

ABSTRACT

ABSTRACT OBJECTIVES: To study the effect of two intravenous maintenance fluids on plasma sodium (Na), and acid-base balance in pediatric intensive care patients during the first 24 h of hospitalization. METHODS: A prospective randomized controlled study was performed, which allocated 233 patients to groups: (A) NaCl 0.9% or (B) NaCl 0.45%. Patients were aged 1 day to 18 years, had normal electrolyte concentrations, and suffered an acute insult (medical/surgical). Main outcome measured: change in plasma sodium. Parametric tests: t-tests, ANOVA, X 2 statistical significance level was set at a = 0.05. RESULTS: Group A (n = 130): serum Na increased by 2.91 (±3.9) mmol/L at 24 h (p < 0.01); 2% patients had Na higher than 150 mmol/L. Mean urinary Na: 106.6 (±56.8) mmol/L. No change in pH at 0 and 24 h. Group B (n = 103): serum Na did not display statistically significant changes. Fifteen percent of the patients had Na < 135 mmol/L at 24 h. The two fluids had different effects on respiratory and post-operative situations. CONCLUSIONS: The use of saline 0.9% was associated with a lower incidence of electrolyte disturbances.


RESUMO OBJETIVO: Estudar o efeito de dois fluidos de manutenção intravenosos sobre o sódio (Na) plasmático e o equilíbrio ácido-base em pacientes de terapia intensiva pediátrica durante as primeiras 24 horas de internação. MÉTODOS: Foi feito um estudo controlado randomizado prospectivo. Alocamos aleatoriamente 233 pacientes para os grupos: (A) NaCl a 0,9% e (B) NaCl a 0,45%. Os pacientes com um dia a 18 anos apresentavam concentrações normais de eletrólitos e sofriam de insulto agudo (médico/cirúrgico). Principal resultado: variação no sódio plasmático. Testes paramétricos: teste t, Anova, qui-quadrado. O nível de relevância estatística foi estabelecido em a = 0,05. RESULTADOS: Grupo A (n = 130): o Na sérico aumentou 2,91 (± 3,9) mmol L-1 em 24 h (p < 0,01); 2% dos pacientes apresentaram Na acima de 150 mmol L-1. Concentração média de Na na urina: 106,6 (± 56,8) mmol L-1. Sem alteração no pH em 0 e 24 horas. Grupo B (n = 103): o Na sérico não apresentou alterações estatisticamente significativas; 15% dos pacientes apresentaram Na < 135 mmol L-1 em 24 h. Os dois fluidos tiveram efeitos diferentes sobre as situações respiratória e pós-operatória. CONCLUSÃO: O uso de solução fisiológica a 0,9% foi associado à menor incidência de distúrbios eletrolíticos.


Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Acid-Base Equilibrium/drug effects , Fluid Therapy/methods , Sodium Chloride/pharmacology , Sodium/metabolism , Fluid Therapy/adverse effects , Hyponatremia/chemically induced , Hyponatremia/drug therapy , Hyponatremia/metabolism , Infusions, Intravenous , Intensive Care Units, Pediatric , Prospective Studies , Sodium Chloride/metabolism , Sodium/blood
13.
Braz. j. microbiol ; 46(2): 347-354, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749729

ABSTRACT

Halophilic microorganisms are able to grow in the presence of salt and are also excellent source of enzymes and biotechnological products, such as exopolysaccharides (EPSs) and polyhydroxyalkanoates (PHAs). Salt-tolerant bacteria were screened in the Organic Composting Production Unit (OCPU) of São Paulo Zoological Park Foundation, which processes 4 ton/day of organic residues including plant matter from the Atlantic Rain Forest, animal manure and carcasses and mud from water treatment. Among the screened microorganisms, eight halotolerant bacteria grew at NaCl concentrations up to 4 M. These cultures were classified based on phylogenetic characteristics and comparative partial 16S rRNA gene sequence analysis as belonging to the genera Staphylococcus, Bacillus and Brevibacterium. The results of this study describe the ability of these halotolerant bacteria to produce some classes of hydrolases, namely, lipases, proteases, amylases and cellulases, and biopolymers. The strain characterized as of Brevibacterium avium presented cellulase and amylase activities up to 4 M NaCl and also produced EPSs and PHAs. These results indicate the biotechnological potential of certain microorganisms recovered from the composting process, including halotolerant species, which have the ability to produce enzymes and biopolymers, offering new perspectives for environmental and industrial applications.


Subject(s)
Bacillus/isolation & purification , Biological Products/analysis , Brevibacterium/isolation & purification , Hydrolases/analysis , Soil Microbiology , Sodium Chloride/metabolism , Staphylococcus/isolation & purification , Brazil , Bacillus/classification , Bacillus/genetics , Bacillus/metabolism , Brevibacterium/classification , Brevibacterium/genetics , Brevibacterium/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Soil , Staphylococcus/classification , Staphylococcus/genetics , Staphylococcus/metabolism
14.
Braz. j. microbiol ; 45(4): 1503-1511, Oct.-Dec. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-741306

ABSTRACT

Extracellular lipases from the endophytic yeast Candida guilliermondii isolated from castor leaves (Ricinus communis L.) were produced using low-cost raw materials such as agro-industrial residues and applying them in the esterification of oleic acid for evaluating their potential use in biodiesel production. After partial purification using ammonium sulfate, the enzyme was characterized and presented higher activity (26.8 ± 1.5 U mL-1) in the presence of 5 mmol L-1 NaCl at 30 ºC and pH 6.5. The production through submerged fermentation was formerly performed in 150 mL erlenmeyer flasks and, once the enzyme production was verified, assays in a 14 L bioreactor were conducted, obtaining 18 ± 1.4 U mL-1. The produced enzyme was applied in the oleic acid esterification under different solvents: hexane, cyclohexane or cyclohexanone) and different acid:alcohol molar ratios. Higher ester conversion rate (81%) was obtained using hexane and the molar ratio of 1:9 was the best conditions using methanol. The results suggest the potential for development of endophytic yeast in the production of biocatalyst through submerged fermentation using agroindustrial residues as culture medium.


Subject(s)
Candida/enzymology , Candida/metabolism , Lipase/isolation & purification , Lipase/metabolism , Candida/growth & development , Candida/isolation & purification , Culture Media/chemistry , Esterification , Endophytes/enzymology , Endophytes/growth & development , Endophytes/isolation & purification , Endophytes/metabolism , Hydrogen-Ion Concentration , Oleic Acid/metabolism , Plant Leaves/microbiology , Ricinus/microbiology , Sodium Chloride/metabolism , Temperature
15.
Braz. j. microbiol ; 45(4): 1541-1550, Oct.-Dec. 2014. tab
Article in English | LILACS | ID: lil-741311

ABSTRACT

Lactic acid bacteria capable of producing bacteriocins and presenting probiotic potential open innovative technological applications in the dairy industry. In this study, a bacteriocinogenic strain (Lactococcus lactis subsp. lactis DF4Mi) was isolated from goat milk, and studied for its antimicrobial activity. The bacteriocin presented a broad spectrum of activity, was sensitive to proteolytic enzymes, resistant to heat and pH extremes, and not affected by the presence of SDS, Tween 20, Tween 80, EDTA or NaCl. Bacteriocin production was dependent on the components of the culture media, especially nitrogen source and salts. When tested by PCR, the bacteriocin gene presented 100% homology to nisin Z gene. These properties indicate that this L. lactis subsp. lactis DF4Mi can be used for enhancement of dairy foods safety and quality.


Subject(s)
Animals , Anti-Bacterial Agents/metabolism , Bacteriocins/metabolism , Lactococcus lactis/metabolism , Milk/microbiology , Amino Acid Sequence , Anti-Bacterial Agents/chemistry , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacteriocins/chemistry , Bacteriocins/genetics , Culture Media/chemistry , Detergents , DNA, Bacterial/genetics , Goats , Hydrogen-Ion Concentration , Lactococcus lactis/growth & development , Molecular Sequence Data , Polymerase Chain Reaction , Protein Stability , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sodium Chloride/metabolism , Temperature
16.
Braz. j. microbiol ; 45(3): 1105-1112, July-Sept. 2014. graf, tab
Article in English | LILACS | ID: lil-727045

ABSTRACT

Studies were conducted to determine the effect of osmotic and matric stress on germination and growth of two Fusarium solani strains, the etiological agent responsible of peanut brown root rot. Both strains had similar osmotic and matric potential ranges that allowed growth, being the latter one narrower. F. solani showed the ability to grow down to -14 MPa at 25 °C in non-ionic modified osmotic medium, while under matric stress this was limited to -8.4 MPa at 25 °C. However, both strains were seen to respond differently to decreasing osmotic and matric potentials, during early stages of germination. One strain (RC 338) showed to be more sensitive to matric than osmotic (non ionic) and the other one (RC 386) showed to be more sensitive to osmotic than matric imposed water stress. After 24 h of incubation, both isolates behaved similarly. The minimum water potential for germination was -8.4 MPa on glycerol amended media and -5.6 MPa for NaCl and PEG amended media, respectively. The knowledge of the water potential range which allow mycelia growth and spore germination of F. solani provides an inside to the likely behaviour of this devastating soilborne plant pathogen in nature and has important practical implications.


Subject(s)
Fusarium/growth & development , Osmotic Pressure , Water/metabolism , Arachis/microbiology , Fusarium/drug effects , Fusarium/radiation effects , Glycerol/metabolism , Plant Diseases/microbiology , Polyethylene Glycols/metabolism , Soil Microbiology , Sodium Chloride/metabolism , Temperature
17.
Braz. j. microbiol ; 45(2): 563-572, Apr.-June 2014. ilus, tab
Article in English | LILACS | ID: lil-723112

ABSTRACT

Halophilic bacteria are commonly found in natural environments containing significant concentration of NaCl such as inland salt lakes and evaporated sea-shore pools, as well as environments such as curing brines, salted food products and saline soils. Dependence on salt is an important phenotypic characteristic of halophilic bacteria, which can be used in the polyphasic characterization of newly discovered microorganisms. In this study the diversity of halophilic bacteria in foreshore soils of Daecheon, Chungnam, and Saemangeum, Jeonbuk, was investigated. Two types of media, namely NA and R2A supplemented with 3%, 5%, 9%, 15%, 20% and 30% NaCl were used. More than 200 halophilic bacteria were isolated and BOX-PCR fingerprinting analysis was done for the typing of the isolates. The BLAST identification results showed that isolated strains were composed of 4 phyla, Firmicutes (60%), Proteobacteria (31%), Bacteriodetes (5%) and Actinobacteria (4%). Isolates were affiliated with 16 genera and 36 species. Bacillus was the dominant genus in the phylum Firmicutes, comprising 24% of the total isolates. Halomonas (12%) and Shewanella (12%) were also found as the main genera. These findings show that the foreshore soil of Daecheon Beach and Saemangeum Sea of Korea represents an untapped source of bacterial biodiversity.


Subject(s)
Biodiversity , Bacteria/classification , Bacteria/growth & development , Soil Microbiology , Bacteria/genetics , Bacteria/isolation & purification , Cluster Analysis , Culture Media/chemistry , DNA Fingerprinting , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Genotype , Korea , Phylogeny , /genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism
18.
Braz. j. microbiol ; 45(2): 627-631, Apr.-June 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-723127

ABSTRACT

Biofilm formation depends on several factors. The influence of different osmolarities on bacterial biofilm formation was studied. Two strains (Enterobacter sp. and Stenotrophomonas sp.) exhibited the most remarkable alterations. Biofilm formation is an important trait and its use has been associated to the protection of organisms against environmental stresses.


Subject(s)
Biofilms/drug effects , Enterobacter/drug effects , Enterobacter/physiology , Stenotrophomonas/drug effects , Stenotrophomonas/physiology , Osmolar Concentration , Sodium Chloride/metabolism , Sorbitol/metabolism
19.
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
20.
Braz. j. microbiol ; 45(1): 89-96, 2014. ilus, tab
Article in English | LILACS | ID: lil-709483

ABSTRACT

This study was conducted to evaluate the antibacterial effect of Carum copticum essential oil (Ajowan EO) against Listeria monocytogenes in fish model system. Ajowan EO chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of Carum copticum essential oil without any significant changes on sensory properties of kutum fish (Rutilus frisii kutum) was assigned. Then the inhibitory effect of Ajowan EO at different concentrations in presence of salt and smoke component was tested on L. monocytogenes growth in fish peptone broth (FPB), kutum broth and cold smoked kutum broth at 4 ºC for 12 days. Ajowan EO completely decreased the number of L. monocytogenes in FPB after 12 days of storage, however, antimicrobial effect of EO significantly reduced in kutum and cold smoked kutum broth. Addition of 4% NaCl and smoke component improved the anti-listerial activity of Ajowan EO in all fish model broths.


Subject(s)
Animals , Anti-Bacterial Agents/pharmacology , Carum/chemistry , Fish Diseases/drug therapy , Fish Diseases/microbiology , Listeria monocytogenes/drug effects , Listeriosis/veterinary , Oils, Volatile/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Colony Count, Microbial , Culture Media/chemistry , Cyprinidae/microbiology , Gas Chromatography-Mass Spectrometry , Listeriosis/drug therapy , Listeriosis/microbiology , Microbial Viability/drug effects , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Sodium Chloride/metabolism , Temperature
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