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1.
Electron. j. biotechnol ; 40: 71-77, July. 2019. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1053491

RESUMO

Background: Burdock (Arctium lappa L.) is a fructan-rich plant with prebiotic potential. The aim of this study was to develop an efficient enzymatic route to prepare fructooligosaccharides (FOS)-rich and highly antioxidative syrup using burdock root as a raw material. Results: Endo-inulinase significantly improved the yield of FOS 2.4-fold while tannase pretreatment further increased the yield of FOS 2.8-fold. Other enzymes, including endo-polygalacturonase, endo-glucanase and endo-xylanase, were able to increase the yield of total soluble sugar by 11.1% (w/w). By this process, a new enzymatic process for burdock syrup was developed and the yield of burdock syrup increased by 25% (w/w), whereas with FOS, total soluble sugars, total soluble protein and total soluble polyphenols were enhanced to 28.8%, 53.3%, 8.9% and 3.3% (w/w), respectively. Additionally, the scavenging abilities of DPPH and hydroxyl radicals, and total antioxidant capacity of the syrup were increased by 23.7%, 51.8% and 35.4%, respectively. Conclusions: Our results could be applied to the development of efficient extraction of valuable products from agricultural materials using enzyme-mediated methods.


Assuntos
Oligossacarídeos/química , Raízes de Plantas/química , Frutose/química , Glicosídeo Hidrolases/metabolismo , Antioxidantes/química , Oligossacarídeos/metabolismo , Poligalacturonase/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Cromatografia Líquida de Alta Pressão , Radical Hidroxila , Arctium , Alimento Funcional , Polifenóis , Frutose/metabolismo , Antioxidantes/metabolismo
2.
Electron. j. biotechnol ; 28: 87-94, July. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1015957

RESUMO

Background: Inferior Tieguanyin oolong tea leaves were treated with tannase. The content and bioactivity of catechins in extracts from the treated tea leaves were investigated to assess the improvement in the quality of inferior Tieguanyin oolong tea. Results: Analysis showed that after treatment, the esterified catechin content decreased by 23.5%, whereas non-galloylated catechin and gallic acid contents increased by 15.3% and 182%, respectively. The extracts from tannase-treated tea leaves showed reduced ability to bind to BSA and decreased tea cream levels. The extracts also exhibited increased antioxidant ability to scavenge OH and DPPH radicals, increased ferric reducing power, and decreased inhibitory effects on pancreatic α-amylase and lipase activities. Conclusions: These results suggested that tannase treatment could improve the quality of inferior Tieguanyin oolong tea leaves.


Assuntos
Chá/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Chá/metabolismo , Chá/química , Temperatura , Catálise , Catequina/análise , Folhas de Planta/enzimologia , Fermentação , Hidrólise , Lipase/antagonistas & inibidores , Lipase/metabolismo , Antioxidantes
3.
Braz. j. microbiol ; 47(4): 1006-1013, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828204

RESUMO

Abstract The search for new biocatalysts has aroused great interest due to the variety of micro-organisms and their role as enzyme producers. Native lipases from Aspergillus niger and Rhizopus javanicus were used to enrich the n-3 long-chain polyunsaturated fatty acids content in the triacylglycerols of soybean oil by acidolysis with free fatty acids from sardine oil in solvent-free media. For the immobilization process, the best lipase/support ratios were 1:3 (w/w) for Aspergillus niger lipase and 1:5 (w/w) for Rhizopus javanicus lipase using Amberlite MB-1. Both lipases maintained constant activity for 6 months at 4 °C. Reaction time, sardine-free fatty acids:soybean oil mole ratio and initial water content of the lipase were investigated to determine their effects on n-3 long-chain polyunsaturated fatty acids incorporation into soybean oil. Structured triacylglycerols with 11.7 and 7.2% of eicosapentaenoic acid + docosahexaenoic acid were obtained using Aspergillus niger lipase and Rhizopus javanicus lipase, decreasing the n-6/n-3 fatty acids ratio of soybean oil (11:1 to 3.5:1 and 4.7:1, respectively). The best reaction conditions were: initial water content of lipase of 0.86% (w/w), sardine-free faty acids:soybean oil mole ratio of 3:1 and reaction time of 36 h, at 40 °C. The significant factors for the acidolysis reaction were the sardine-free fatty acids:soybean oil mole ratio and reaction time. The characterization of structured triacylglycerols was obtained using easy ambient sonic-spray ionization mass spectrometry. The enzymatic reaction led to the formation of many structured triacylglycerols containing eicosapentaenoic acid, docosahexaenoic acid or both polyunsaturated fatty acids.


Assuntos
Triglicerídeos , Hidrolases de Éster Carboxílico/química , Ácidos Graxos Ômega-3 , Enzimas Imobilizadas , Triglicerídeos/química , Estabilidade Enzimática , Ácidos Graxos Ômega-3/síntese química , Cromatografia Gasosa , Espectrometria de Massas por Ionização por Electrospray
4.
Arq. gastroenterol ; 52(3): 195-199, July-Sep. 2015. tab
Artigo em Inglês | LILACS | ID: lil-762877

RESUMO

BackgroundSpontaneous bacterial peritonitis is defined as an ascetic fluid infection without an evident intra-abdominal surgically treatable source. Spontaneous bacterial peritonitis is one of the severe complications in patients with cirrhosis and ascites. Without early antibiotic treatment, this complication is associated with high mortality rate; therefore, early diagnosis and treatment of spontaneous bacterial peritonitis is necessary for survival. Leukocyte esterase reagent can rapidly diagnose the spontaneous bacterial peritonitis.ObjectiveThis study aimed to find out the diagnostic accuracy of leukocyte esterase dipstick test for the diagnosis of spontaneous bacterial peritonitis.MethodsA single centered hospital-based cross-sectional study was conducted during July 2013 to August 2014 on children with cirrhotic liver disease and ascites who were admitted in the Department of Pediatric Gastroenterology in Nemazee Hospital affiliated to Shiraz University of Medical Sciences (Iran). All patients underwent abdominal paracentesis, and the ascitic fluid was processed for cell count, leukocyte esterase reagent strip test (Combiscreen SL10) and culture. Spontaneous bacterial peritonitis was defined as having a polymorphonuclear count (PMN ≥250/m3) in ascitic fluid. Sensitivity, specificity, positive predictive value and negative predictive value of leukocyte esterase test were calculated according to the formula.ResultsTotally, 150 ascitic fluid sample of cirrhotic male patients (53.2%) and their mean age (4.33±1.88 years) were analyzed. Biliary atresia (n=44, 29.4%) and idiopathic neonatal hepatitis (n=29, 19.3%) were the most frequent etiology of cirrhosis. Also, abdominal pain (68.6%) and distension (64%) were the most common presenting complaint. Of all cases, 41patients (27.35%) were diagnosed to have spontaneous bacterial peritonitis (PMN ≥250/mm3). Sensitivity and specificity of leukocyte esterase reagent test according to PMNs ≥250mm3 were 87.80% and 91.74%, also on ascitic fluid culture results were 88.23% and 77.44%. Positive predictive value and negative predictive value of this test in PMNs ≥250mm3 were 80% and 95.23% and in cases with positive culture 33.33% and 98.09% were obtained, respectively. Efficiency of leukocyte esterase reagent test in diagnosing spontaneous bacterial peritonitis, according to PMNs ≥250mm3 and culture results were 90.66% and 78.66%.ConclusionThe leukocyte esterase strip test may be used as rapid test for diagnosis of spontaneous bacterial peritonitis due to its high diagnostic validity.


ContextoA peritonite bacteriana espontânea é definida como uma infecção do fluido ascítico sem evidente origem intra-abdominal cirurgicamente tratável. A peritonite bacteriana espontânea é uma das complicações graves em pacientes com cirrose e ascite. Sem tratamento antibiótico precoce, esta complicação é associada com alta taxa de mortalidade. Portanto, o diagnóstico precoce e tratamento de peritonite bacteriana espontânea são necessários para a sobrevivência. O reagente de esterase de leucócitos pode rapidamente diagnosticar a peritonite bacteriana espontânea.ObjetivoEste estudo teve como objetivo descobrir a acurácia diagnóstica do teste com tiras de esterase de leucócitos para o diagnóstico de peritonite bacteriana espontânea.MétodosUm estudo transversal hospitalar unicêntrico foi realizado entre julho de 2013 e agosto de 2014 em crianças com cirrose hepática e ascite que foram admitidas no Departamento de Gastroenterologia Pediátrica no Hospital de Nemazee afiliado à Universidade de Ciencias Médicas de Shiraz (Irã). Todos os pacientes foram submetidos a paracentese abdominal, e o líquido ascítico foi processado para contagem de células, teste de tira de reagente de esterase de leucócitos (Combiscreen SL10) e cultura. Peritonite bacteriana espontânea foi definida como tendo uma contagem de polimorfonucleares (PMN ≥250/m3) no líquido ascítico. Sensibilidade, especificidade, valor preditivo positivo negativo do teste de esterase de leucócitos foram calculados de acordo com a fórmula.ResultadosForam analisados um total de 150 amostras de líquido ascítico de pacientes cirróticos; (53,2%) eram do sexo masculino e sua média de idade (4,33±1,88 anos). A atresia biliar (n=44, 29,4%) e hepatite neonatal idiopática (n=29, 19,3%) foram as etiologias mais frequentes de cirrose. Além disso, dor abdominal (68,6%) e distensão (64%) foram as queixas mais comuns de apresentação. De todos os casos, 41 (27,35%) foram diagnosticados com peritonite bacteriana espontânea (PMN ≥250/mm3). A sensibilidade e especificidade do teste de reagente de esterase de leucócitos segundo PMN ≥250mm3 foi de 87,80% e 91,74% e, para os resultados de cultura de líquido ascítico, de 88,23% e 77,44%. Valor preditivo positivo e valor preditivo negativo do teste em PMN ≥250mm3 foi de 80% e 95,23% e em casos com cultura positiva 33,33% e 98,09%, respectivamente. A eficiência do teste de reagente esterase de leucócitos no diagnóstico de peritonite bacteriana espontânea, de acordo com resultados de ≥250mm3 e cultura PMN, foi de 90,66% e 78,66%.ConclusãoO teste de tiras de esterase de leucócitos pode ser usado como um teste rápido para diagnóstico de peritonite bacteriana espontânea, devido a sua alta validade diagnóstica.


Assuntos
Feminino , Humanos , Masculino , Ascite/complicações , Hidrolases de Éster Carboxílico , Cirrose Hepática/complicações , Peritonite/diagnóstico , Peritonite/etiologia , Fitas Reagentes , Líquido Ascítico , Ascite/microbiologia , Infecções Bacterianas/microbiologia , Estudos Transversais , Peritonite/microbiologia , Sensibilidade e Especificidade
5.
Clinics ; 69(10): 677-682, 10/2014. tab
Artigo em Inglês | LILACS | ID: lil-730467

RESUMO

OBJECTIVES: To determine the serum and tissue levels of markers of impaired oxidative metabolism and correlate these levels with the histopathology and Alvarado score of acute appendicitis patients. METHOD: Sixty-five acute appendicitis patients (mean age, 31.4±12.06 years; male/female, 30/35) and 30 healthy control subjects were studied. The Alvarado score was recorded. Serum samples were obtained before surgery and 12 hours postoperatively to examine the total antioxidant status, total oxidant status, paraoxonase, stimulated paraoxonase, arylesterase, catalase, myeloperoxidase, ceruloplasmin, oxidative stress markers (advanced oxidized protein products and total thiol level) and ischemia-modified albumin. Surgical specimens were also evaluated. RESULTS: The diagnoses were acute appendicitis (n = 37), perforated appendicitis (n = 8), phlegmonous appendicitis (n = 12), perforated+phlegmonous appendicitis (n = 4), or no appendicitis (n = 4). The Alvarado score of the acute appendicitis group was significantly lower than that of the perforated+phlegmonous appendicitis group (p = 0.004). The serum total antioxidant status, total thiol level, advanced oxidized protein products, total oxidant status, catalase, arylesterase, and ischemia-modified albumin levels were significantly different between the acute appendicitis and control groups. There was no correlation between the pathological extent of acute appendicitis and the tissue levels of the markers; additionally, there was no correlation between the tissue and serum levels of any of the parameters. CONCLUSIONS: The imbalance of oxidant/antioxidant systems plays a role in the pathogenesis acute appendicitis. The Alvarado score can successfully predict the presence and extent of acute appendicitis. .


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Apendicite/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/análise , Doença Aguda , Apendicectomia , Antioxidantes/análise , Arildialquilfosfatase/análise , Biomarcadores/análise , Estudos de Casos e Controles , Hidrolases de Éster Carboxílico/análise , Estudos Prospectivos , Peroxidases/análise , Valores de Referência , Espécies Reativas de Oxigênio/metabolismo , Estatísticas não Paramétricas , Albumina Sérica/análise
6.
Braz. j. microbiol ; 44(2): 559-567, 2013. tab
Artigo em Inglês | LILACS | ID: lil-688589

RESUMO

One variable at a time procedure was used to evaluate the effect of qualitative variables on the production of tannase from Aspergillus niger Van Tieghem. These variables including: fermentation technique, agitation condition, tannins source, adding carbohydrates incorporation with tannic acid, nitrogen source type and divalent cations. Submerged fermentation under intermittent shaking gave the highest total tannase activity. Maximum extracellular tannase activity (305 units/ 50 mL) was attained in medium containing tannic acid as tannins source and sodium nitrate as nitrogen source at 30 ºC for 96 h. All added carbohydrates showed significant adverse effects on the production of tannase. All tested divalent cations significantly decreased tannase production. Moreover, split plot design was carried out to study the effect of fermentation temperature and fermentation time on tannase production. The results indicated maximum tannase production (312.7 units/50 mL) at 35 ºC for 96 h. In other words, increasing fermentation temperature from 30 ºC to 35 ºC resulted in increasing tannase production.


Assuntos
Aspergillus niger/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Cátions Bivalentes/metabolismo , Meios de Cultura/química , Inibidores Enzimáticos/metabolismo , Fermentação , Temperatura , Fatores de Tempo
7.
Braz. j. microbiol ; 44(2): 569-576, 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-688590

RESUMO

The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 ºC and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture.


Assuntos
Aspergillus/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Xilosidases/metabolismo , beta-Glucosidase/metabolismo , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Carbono/metabolismo , Meios de Cultura/química , Nitrogênio/metabolismo , Temperatura
8.
Electron. j. biotechnol ; 15(5): 4-4, Sept. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-657663

RESUMO

Background: Tannases are enzymes that may be used in different industrial sectors as, for example, food and pharmaceutical. They are obtained mainly from microorganisms, as filamentous fungi. However, the diversity of fungi stays poorly explored for tannase production. In this article, Aspergillus ochraceus is presented as a new source of tannase with interesting features for biotechnological applications. Results: Extracellular tannase production was induced when the fungus was cultured in Khanna medium with tannic acid as carbon source. The extracellular tannase was purified 9-fold with 2 percent recovery and a single band corresponding to 85 kDa was observed in SDS-PAGE. The native apparent molecular mass was estimated as 112 kDa. Optima of temperature and pH were 40ºC and 5.0, respectively. The enzyme was fully stable from 40ºC to 60ºC during 1 hr. The activity was enhanced by Mn2+ (33-39 percent) and NH4+ (15 percent). The purified tannase hydrolyzed tannic acid and methyl gallate with Km of 0.76 mM and 0.72 mM, respectively, and Vmax of 0.92 U/mg protein and 0.68 U/mg protein, respectively. The analysis of a partial sequence of the tannase encoding gene showed an open read frame of 567 bp and a sequence of 199 amino acids were predicted. TLC analysis revealed the presence of gallic acid as a tannic acid hydrolysis product. Conclusion: The extracellular tannase produced by A. ochraceus showed distinctive characteristics such as monomeric structure and activation by Mn2+, suggesting a new kind of fungal tannases with biotechnological potential. Further, it was the first time that a partial gene sequence for A. ochraceus tannase was described.


Assuntos
Aspergillus ochraceus/enzimologia , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Eletroforese , Fermentação , Concentração de Íons de Hidrogênio , Taninos Hidrolisáveis , Reação em Cadeia da Polimerase , Temperatura
9.
Electron. j. biotechnol ; 15(3): 9-9, May 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640553

RESUMO

Background: Consistency is one of the main traits that define commercial quality and price of tomato paste. Pectins are partially responsible for consistency in tomato paste, therefore enzymatic pectin modification could be used to increase paste consistency. Results: This work reports the effects of a commercial enzymatic preparation of pectin-methyl-esterase (PME) (NovoShape™) on tomato paste consistency taking into account variables as enzyme/substrate ratio (0,1 percent w/w - 1 percent w/w), reaction time (0 hr - 3 hrs) and reaction temperature (40ºC-60ºC). The results indicate that NovoShape™ increased consistency when reaction temperature ranged from 40 to 50ºC with an enzyme/substrate ratio of 0.5 to 1 (l PME solution/g tomato paste on dry base). On the other hand, enzymatic treatment was not effective at 60ºC with an enzyme/substrate ratio of 0.1 percent. Conclusions: Based on these results, addition of NovoShape™ is a good technological approach to increase tomato paste consistency.


Assuntos
Hidrolases de Éster Carboxílico/química , Lycopersicon esculentum/enzimologia , Manipulação de Alimentos , Pectinas/química , Temperatura , Viscosidade
10.
Clinics ; 65(3): 285-290, 2010. tab
Artigo em Inglês | LILACS | ID: lil-544021

RESUMO

INTRODUCTION: Laparoscopic cholecystectomy is the gold standard for the treatment of gallstone disease; however, adverse hemodynamic changes induced by increased intraabdominal pressure due to pneumoperitoneum are known to occur. Herein, we investigated the effects of pneumoperitoneum on oxidative stress markers, including paraoxonase, arylesterase, total oxidant status, and total antioxidant status, during laparoscopic cholecystectomy. PATIENTS AND METHODS: Patients that underwent a laparoscopic cholecystectomy were classified as Group I, whereas patients that underwent surgical procedures for an abdominal wall hernia under general anesthesia were classified as Group II. Blood samples were obtained during the preoperative period, the perioperative period, and 24 hours after surgery (postoperative day 1). Leukocyte counts, neutrophil rates, paraoxonase activities, arylesterase activities, and total oxidant and antioxidant status levels were measured. RESULTS: The differences in leukocyte counts and neutrophil rates were not significant between the two groups. In Group I, no significant differences in the total oxidant and antioxidant status levels were identified; however, paraoxonase and arylesterase levels were lower on postoperative day 1. No significant changes were observed in the total oxidant status, total antioxidant status, and paraoxonase or arylesterase activities in Group II. The perioperative total antioxidant status and arylesterase level were higher in Group I in comparison to Group II. CONCLUSION: Paraoxonase and arylesterase levels are useful markers in the evaluation of oxidative stress caused by intraabdominal pressure due to pneumoperitoneum.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antioxidantes/análise , Arildialquilfosfatase/sangue , Hidrolases de Éster Carboxílico/sangue , Colecistectomia Laparoscópica/efeitos adversos , Cálculos Biliares/cirurgia , Estresse Oxidativo/fisiologia , Biomarcadores/sangue , Cálculos Biliares/sangue , Hérnia Ventral/cirurgia , Contagem de Leucócitos , Neutrófilos , Pneumoperitônio Artificial/efeitos adversos , Estatísticas não Paramétricas , Adulto Jovem
11.
Clinics ; 65(2): 175-179, 2010. tab
Artigo em Inglês | LILACS | ID: lil-539834

RESUMO

OBJECTIVES: The aim of this study was to investigate the activities of serum paraoxonase and arylesterase in patients with ankylosing spondylitis with respect to those of healthy controls, to assess whether these enzyme levels are related to disease activity and functional capacity. METHODS: The study included 32 patients with ankylosing spondylitis whose diagnoses were made according to the modified New York criteria as well as 25 healthy controls matched for age and sex. The Bath Ankylosing Spondylitis Disease Activity Index and the Bath Ankylosing Spondylitis Functional Index were applied to the ankylosing spondylitis patients. As laboratory parameters, the erythrocyte sedimentation rate and serum C-reactive protein level were measured in patients and control subjects. Paraoxonase and arylesterase enzyme activities were measured using appropriate methods. RESULTS: No statistically significant differences (p>0.05) were found between the ankylosing spondylitis patients and controls in terms of serum paraoxonase or arylesterase levels. Furthermore, there was no correlation between clinical and laboratory parameters in patients with ankylosing spondylitis. CONCLUSION: Serum paraoxonase and arylesterase levels in ankylosing spondylitis patients may not differ from those of healthy controls, and there is no significant correlation between antioxidant parameters and the Bath Ankylosing Spondylitis Disease Activity Index or Bath Ankylosing Spondylitis Functional Index scores in ankylosing spondylitis patients. Further research is needed to provide deeper understanding of this disease.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Arildialquilfosfatase/sangue , Hidrolases de Éster Carboxílico/sangue , Espondilite Anquilosante/enzimologia , Sedimentação Sanguínea , Biomarcadores/sangue , Proteína C-Reativa/análise , Estudos de Casos e Controles , Índice de Gravidade de Doença , Adulto Jovem
12.
Arch. cardiol. Méx ; 78(4): 360-368, Oct.-Dec. 2008.
Artigo em Espanhol | LILACS | ID: lil-565638

RESUMO

PURPOSE: To determine the Paraoxonase-1 (PON1) activity as well as its pheno- and genotypes at position 192 in Mexican subjects with diagnosis of coronary heart disease (CHD). METHODS: We determined the PON1-192 polymorphism by PCR-RFLP, and serum PON1 activity, using either paraoxon (PONase activity) or phenylacetate (ARE activity) as substrates, in 155 clinically healthy individuals (control group), and 155 patients with at least one myocardial infarction (CHD group). The biochemical A/B phenotype was determined by the ratio of the NaCI 1 M-stimulated PONase activity divided by the ARE activity. RESULTS: We found significantly lower PONase and ARE activities in CHD patients as compared to controls (233.1 +/- 102.1 vs. 295.8 +/- 159.1 nmol/min/mL, and 103.1 +/- 33.7 vs 220.2 +/- 120.7 micromol/min/mL, respectively, p<0.05 for both). Allele and genotype frequencies for PON1-192 were similar in CHD patients and healthy controls. Moreover, in the control group, the PON1-192 Q/R genotype did not matched with the A/B phenotype as has been proposed by other studies. CONCLUSIONS: There were important differences in the ARE and PONase activities between Mexican CHD patients and controls, suggesting that PON1 activity could be a good marker of CHD risk, whereas PON1-192 lacks of value to assess such risk.


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Arildialquilfosfatase , Hidrolases de Éster Carboxílico , Doença da Artéria Coronariana/enzimologia , Arildialquilfosfatase/sangue , Arildialquilfosfatase , Estudos Transversais , Hidrolases de Éster Carboxílico/sangue , Hidrolases de Éster Carboxílico , HDL-Colesterol/sangue , Genótipo , México , Infarto do Miocárdio/enzimologia , Fenótipo , Polimorfismo Genético
13.
Braz. j. infect. dis ; 11(5): 479-481, Oct. 2007. tab
Artigo em Inglês | LILACS | ID: lil-465772

RESUMO

We evaluated the performance of automated-flow cytometry, urinalysis dipsticks and microscopic urine sediment analysis as predictors of urinary tract infection. Urine cultures were used as a reference method for comparison. Six-hundred-seventy-five urine samples from hospitalized and not hospitalized patients attended at Hospital Mãe de Deus, Porto Alegre, in south Brazil, were included in the study. Among the individual measures analyzed, intense bacteriuria in the microscopic analysis of urinary sediment gave an accuracy of 92.9 percent. A combination between intense bacteriuria (microscopic analysis) and >20 leukocytes per µL of urine (flow cytometry) gave a higher accuracy (97.3 percent). We conclude that though it is laborious, microscopic urinalysis is a good analytical tool. Taken together with flow cytometry and dipsticks, we obtained a clinically-acceptable prediction of urinary-tract infection.


Assuntos
Feminino , Humanos , Masculino , Urinálise/métodos , Infecções Urinárias/diagnóstico , Bacteriúria/diagnóstico , Bacteriúria/microbiologia , Hidrolases de Éster Carboxílico , Estudos de Viabilidade , Citometria de Fluxo , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Infecções Urinárias/microbiologia
14.
Electron. j. biotechnol ; 10(2): 191-199, Apr. 15, 2007. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-499182

RESUMO

A biochemical characterization of the tannase from a Paecilomyces variotii strain isolated in Sao Paulo, Brazil was carried out. Paecilomyces variotii is a strain obtained from the screening of five hundred fungi that were tested for their production of tannase. The enzyme produced was partially purified using ammonium sulfate precipitation followed by ion exchange chromatography, diethylaminoethyl (DEAE)-Sepharose. Effects of temperature and pH on the activity of crude tannase crude and purified tannase was studied. Km was found to be 0.61 ‘mol and Vmax = 0.55 U/mL. Temperature of 40 to 65øC and pH 4.5 to 6.5 were optimum for tannase activity and stability; it could find potential use in the food-processing industry. The effects of different inhibitors, surfactants and chelators on the enzyme activity were also studied


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Paecilomyces/enzimologia , Cromatografia , Fermentação , Concentração de Íons de Hidrogênio , Hidrolases de Éster Carboxílico/isolamento & purificação , Cinética , Peso Molecular , Temperatura
15.
Säo Paulo med. j ; 124(3): 141-144, May-June. 2006. tab
Artigo em Inglês, Português | LILACS | ID: lil-435892

RESUMO

CONTEXT AND OBJECTIVE: Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication of cirrhotic patients with ascites. It has been proposed that the reagent strip for leukocyte esterase designed for the testing of urine (Combur test® UX) could be a useful tool for diagnosing SPB. The aim of this study was to assess the sensitivity and specificity of urine test strips for diagnosing SBP in cirrhotic patients with ascites. DESIGN AND SETTING: Prospective study, at a university hospital in northeastern Brazil. METHODS: Forty-two unselected consecutive cirrhotic patients (32 males; mean age: 51.7 ± years) were included, and a total of 100 paracenteses were performed. All ascitic fluid samples were analyzed using the reagent strip and cytology, neutrophils, lymphocyte count, appropriate biochemical tests and culturing. The strips were considered positive if the color became purple on a colorimetric scale. RESULTS: Nine patients were diagnosed with SBP using cytology (> 250 neutrophils/mm³), and the strips were positive for all these nine patients with SBP. In one sample, the strip was positive but the neutrophil count was less than 250 cells/mm³. For 86 samples, both the strips and cytology were negative. At the threshold of 250 neutrophils/mm³ in ascitic fluid, the sensitivity, specificity, positive predictive value and negative predictive value for the strips were respectively 100 percent, 98.9 percent, 92.3 percent and 100 percent. CONCLUSION: The Combur test® UX urine screening test is a very sensitive and specific method for diagnosing SBP in cirrhotic patients with ascites.


CONTEXTO E OBJETIVO: Peritonite bacteriana espontânea (PBE) é uma freqüente e grave complicação em pacientes cirróticos com ascite. Vem sendo proposto o uso de fitas reagente para esterase leucocitária, utilizadas para diagnóstico de infecção urinária, como instrumento para diagnosticar PBE. O objetivo deste estudo é avaliar a sensibilidade e a especificidade da fita reagente Combur Test® UX no diagnóstico de PBE em pacientes cirróticos com ascite. TIPO DE ESTUDO E LOCAL: Estudo prospectivo, realizado no Hospital Universitário Walter Cantídio, Fortaleza, Ceará, Brasil. MÉTODOS: Quarenta e dois pacientes consecutivos, não selecionados (32 homens, com média de idade de 51,7 ± anos) foram incluídos e um total de 100 paracenteses foram realizadas. O líquido ascítico foi avaliado pela fita reagente (Combur Test® UX), citologia, contagem de neutrófilos, linfócitos, testes bioquímicos e cultura. As fitas reagentes foram consideradas positivas se havia mudança na cor para roxo na escala colorimétrica fornecida pelo fabricante. RESULTADOS: Foram diagnosticados nove pacientes com PBE pela citologia (> 250 neutrófilos/mm³), estando a fita Combur Test® UX positiva em todos os nove pacientes. Em uma amostra o teste da fita foi positivo, embora a contagem de neutrófilos fosse < 250 células/mm³. Nas outras 86 amostras ambos os testes foram negativos. Tendo-se como ponto de corte 250 PMN/mm³ no líquido ascítico, a sensibilidade, a especificidade, o valor preditivo positivo e o valor preditivo negativo foram respectivamente 100 por cento, 98,9 por cento, 92,3 por cento e 100 por cento. CONCLUSÕES: Combur Test® UX (fita reagente para urinanálise) é um método sensível e específico para o diagnóstico de PBE em pacientes cirróticos com ascite.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Infecções Bacterianas/diagnóstico , Hidrolases de Éster Carboxílico , Cirrose Hepática/complicações , Peritonite/diagnóstico , Fitas Reagentes/normas , Líquido Ascítico , Ascite/complicações , Técnicas Bacteriológicas , Brasil , Infecções Bacterianas/microbiologia , Contagem de Leucócitos , Paracentese , Estudos Prospectivos , Peritonite/microbiologia , Sensibilidade e Especificidade
16.
Electron. j. biotechnol ; 7(1): 9-29, Apr. 2004. ilus, graf
Artigo em Inglês | LILACS | ID: lil-363993

RESUMO

Pectin methylesterase (PME) is an enzyme located in the plant cell wall of higher plants whose physiological role is largely unknown. We had isolated a PME gene from a tomato genomic library, including 2.59 kb of 5üL flanking region and the coding region. Both coding and promoter region were sequenced and computer analyzed. Tobacco transgenic plants were created harboring constructs in which 2.596 Kb, 1.306 Kb and 0.267 Kb sizes of the promoter were driving the expression of âÀ-Glucuronidase gene (GUS). GUS activity was studied by histochemical and fluorometric assays. Two introns of 106 and 1039 bp were found in the coding region and phylogenetic analysis placed this PME gene closer to genes from Citrus sinensis and Arabidopsis thaliana than tomato fruit-specific PME genes. In the promoter, it was found direct repeats, perfect inverted repeats and light responsive elements. GUS histochemical analysis showed activity in all plant tissues with the exception of pollen. The reduction in the promoter size induced a reduction in GUS activity in root, stem and leaf. Furthermore, root and leaf showed the highest and lowest activity, respectively. We had isolated a tomato PME gene with novel characteristics as compared with other known PME genes from tomato.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Lycopersicon esculentum/enzimologia , Lycopersicon esculentum/genética , Tabaco/enzimologia , Tabaco/genética , Clonagem Molecular , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucuronidase/metabolismo , Hidrolases de Éster Carboxílico/fisiologia , Dados de Sequência Molecular , Plantas Tóxicas , Regiões Promotoras Genéticas , Plantas Geneticamente Modificadas/genética
17.
Genet. mol. res. (Online) ; 3(1): 85-91, Mar. 2004.
Artigo em Inglês | LILACS | ID: lil-417582

RESUMO

Chromobacterium violaceum presents a distinctive phenotypic characteristic, the production of a deep violet pigment named violacein. Although the physiological function of this pigment is not well understood, the sequencing of the genome of this bacterium has given some insight into the mechanisms and control of violacein production. It was found that erythrose-4-phosphate (E4P), a precursor to aromatic amino acid biosynthesis, is produced by the non-oxidative portion of the hexose monophosphate pathway, since it lacks 6-phosphogluconate dehydrogenase. All genes leading from E4P plus phosphoenolpyruvate to tryptophan are present in the genome. Nevertheless, these genes are not organized in an operon, as in E. coli, indicating that other mechanisms are involved in expression. The sequencing data also indicated the presence and organization of an operon for violacein biosynthesis. Three of the four gene products of this operon presented similarity with nucleotide-dependent monooxygenases and one with a limiting enzyme polyketide synthase. As previously suggested, genes encoding proteins involved in quorum sensing control by N-hexanoyl-homoserine-lactone, an autoinducer signal molecule, are present in the bacterial genome. These data should help guide strategies to increase violacein biosynthesis, a potentially useful molecule


Assuntos
Chromobacterium/genética , Indóis/metabolismo , Chromobacterium/metabolismo , Complexos Multienzimáticos/biossíntese , Complexos Multienzimáticos/genética , Fosfatos Açúcares/genética , Fosfatos Açúcares/metabolismo , Hidrolases de Éster Carboxílico/biossíntese , Hidrolases de Éster Carboxílico/genética , Indóis/química , Triptofano/biossíntese , Triptofano/genética
18.
Rev. argent. microbiol ; 31(4): 201-204, oct.-dec. 1999.
Artigo em Inglês | LILACS | ID: lil-332547

RESUMO

Bacterial survival in natural environments involves the ability of scavenging nutrients and energy sources. Polyhydroxyalkanoates (PHAs) are intracellular polymers that endow bacteria with enhanced survival capabilities in adverse environmental conditions. In this paper we compared survival of Pseudomonas oleovorans wild type and PHA depolymerase mutant strains in natural river waters by using microcosms. Experiments were performed with water samples collected from the Rio de la Plata. The survival of the P. oleovorans strain capable of degrading PHA was higher in raw river water compared to the depolymerase negative mutant strain. Bacterial numbers decreased during the experiment. At the end of the experiment, the difference in the number of cells between wild type and mutant strains was of 3 orders of magnitude. Mutants deficient in PHA degradation are useful to study the importance of reserve polymers in the survival of bacterial species in natural environments. They could also provide an adequate system for the analysis of the role of PHA in the tolerance to physical or chemical stress agents.


Assuntos
Água Doce/microbiologia , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Pseudomonas , Microbiologia da Água , Ecologia , Mutação
19.
Braz. j. med. biol. res ; 31(9): 1113-8, sept. 1998. tab
Artigo em Inglês | LILACS | ID: lil-222957

RESUMO

The activities of aspirin (acetylsalicylic acid)-esterases were measured in several tissues (liver, kidney, adrenal glands, brain and serum) from adult male and female Wistar rats. In males, both aspirin-esterase I (assayed at pH 5.5) and II (assayed at pH 7.4) activities were higher in liver homogenates when compared to females (aspirin-esterase I: males 48.9 ñ 4.8 (N = 8) and females 29.3 ñ 4.2 (N = 8) nmol of salicylic acid formed min-1 mg protein-1; aspirin-esterase II: males 41.4 ñ 4.1 (N = 8) and females 26.1 ñ 4.5 (N = 8) nmol of salicylic acid formed min-1 mg protein-1, P<0.001). In serum, enzyme activity was higher in females than in males (aspirin-esterase I: males 0.85 ñ 0.06 (N = 6) and females 1.18 ñ 0.11 (N = 6) nmol of salicylic acid formed min-1 mg protein-1; aspirin-esterase II: males 1.03 ñ 0.13 (N = 6) and females 1.34 ñ 0.11 (N = 6) nmol of salicylic acid formed min-1 mg protein-1, P<0.001). In the other tissues assayed, no statistically significant difference between males and females was found. There were no statistically significant differences when the enzymes were assayed in different phases of the estrous cycle in liver and serum. These results show that the differences in aspirin-esterase activity observed between males and females are not due to the estrous cycle. The gender difference obtained in our study may indicate an involvement of gonadal hormones in the control of the hydrolysis of aspirin. This possibility is currently under investigation.


Assuntos
Feminino , Animais , Ratos , Aspirina/farmacocinética , Hidrolases de Éster Carboxílico/metabolismo , Diferenciação Sexual , Glândulas Suprarrenais/enzimologia , Encéfalo/enzimologia , Hidrolases de Éster Carboxílico/sangue , Estro , Rim/enzimologia , Fígado/enzimologia , Ratos Wistar , Salicilatos/sangue , Fatores Sexuais
20.
Acta bioquím. clín. latinoam ; 25(4): 435-42, dic.1991. ilus
Artigo em Espanhol | LILACS | ID: lil-105862

RESUMO

Se estudiaron comparativamente las esterasas de las cepas de Tribolium castaneum ULP (suceptible) y ML (resistente a malatión). La actividad de esterasas que hidrolizan acetato de * y ß naftol presentes en homogenatos de T. castaneum fue mayor en la cepa susceptible ML, mientras que la actividad frente al acetato de tiofenilo fue similar en ambas cepas. La distribución subcelular de la actividad esterástica frente al PTA mostró diferencias en ambas cepas. En los homogenatos de insectos de la cepa susceptible se observó que a mayor velocidad de centrifugación el sobrenadante resultó considerablemente más activo en la hidrólisis de acetato de tiofenilo. Se supone que ese resultado se debe a la presencia de un inhibidor endógeno no dializable, de peso molecular tal que puede ser parcialmente precipitado a 10.000g y en mayor medida a 100.000g. Los zimogramas de esterasas no inhibibles por eserina separadas por electroforesis en gel de poliacrilamida y reveladas con * y ß naftilacetato, mostraron, en todos los casos, una única banda que fue clasificada como aril o acetil esterasa. Los resultados descriptos encuadran en la teoría de la aliesterasa mutada, postulada para casos de resistencia al malatión, descriptos en otas especies de insectos


Assuntos
Esterases/análise , Hidrolases de Éster Carboxílico/isolamento & purificação , Malation , Tribolium/enzimologia , Acetilesterase/análise , Acetilesterase/genética , Ensaios Enzimáticos Clínicos , Eletroforese em Gel de Poliacrilamida , Esterases/genética , Hidrolases de Éster Carboxílico/análise , Hidrolases de Éster Carboxílico/metabolismo , Resistência a Inseticidas/genética , Inseticidas Organofosforados , Insetos , Tribolium/classificação
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