Consulta: subjectFacets:"Inhibitors"
Registros recuperados: 11
Data/hora: 02/06/2024 03:31:21

Heterotrophic Bacteria Show Weak Competition for Nitrogen in Mediterranean Coastal Waters (Thau Lagoon) in Autumn
Provedor de dados: 5
Autores: Trottet, Aurore; Leboulanger, Christophe; Vidussi, Francesca; Pete, Romain; Bouvy, Marc; Fouilland, Eric.
The importance of heterotrophic bacteria relative to phytoplankton in the uptake of ammonium and nitrate was studied in Mediterranean coastal waters (Thau Lagoon) during autumn, when the Mediterranean Sea received the greatest allochthonous nutrient loads. Specific inhibitors and size-fractionation methods were used in combination with isotopic N-15 tracers. NO3 (-) and NH4 (+) uptake was dominated by phytoplankton (60 % on average) during the study period, which included a flood event. Despite lower biomass specific NH4 (+) and NO3 uptake rates, free-living heterotrophic bacteria contributed significantly (&gt; 30 %) to total microbial NH4 (+) and NO3 (-) uptake rates in low chlorophyll waters. Under these conditions, heterotrophic bacteria may be...
Tipo: Text
Palavras-chave: Bacteria; Phytoplankton; Inhibitors; Size fractionation; Nitrogen uptake; Dissolved inorganic nitrogen.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00314/42497/41907.pdf

Induction of ovulation and stimulation of spermation by LHRH or an LHRH analog associated or not with pimozide. Effects on some teleost fish.
Provedor de dados: 5
Autores: Billard, R; Weil, C; Barnabe, G.
Effectiveness of LHRH and one of its analogs (LHRH-A = D-Ala super(6) ethylamide) on induction of ovulation and stimulation of spermiation is reviewed here. LHRH was also combined with pimozide, an anti-dopaminergic agent, to try to cancel dopamine inhibition of gonatotropin (GtH) release. LHRH-A alone (50 mu g/kg) did not initiate ovulation but only oocyte maturation. When pimozide (10 mg/kg) and LHRH-A (50 mu g/kg) were combined, gonadotropic hormone secretion was significantly increased, causing ovulation and stimulating spermiation. This combination advanced ovulation in trout. Trout egg quality was markedly altered by the pimozide treatment; it remains to be tested in carp. In sea bass, LHRH-A was much more effective than LHRH, and ovulation was...
Tipo: Text
Palavras-chave: Salmonidae; Dicentrarchus labrax; Sparidae; Cyprinidae; Teleostei; Pisces; Inhibitors; Sex hormones; Sexual maturity; Spermatogenesis; Ovulation; Induced breeding; Sexual reproduction.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/acte-1218.pdf

Professor José Roberto Giglio and toxinnology in Brazil: 48 years in research
Provedor de dados: 80
Autores: Soares,A. M.; Oliveira,C. Z.; Santana,C. D.; Menaldo,D. L.; Silveira,L. B.; Teixeira,S. S.; Rueda,A. Q.; Marcussi,S.
This work succinctly describes the professional and scientific life of Dr. José R. Giglio, one of the most outstanding Brazilian researchers in the field of Toxinology. During his long and successful career, he has made major contributions, especially in elucidating the function, structure, and mechanisms of action of animal venom proteins (from snakes, scorpions and spiders) as well as the characterization of antibodies and several inhibitors of venoms and toxins. We present here a brief history of Dr. Giglio’s personal and professional life, also reporting some of his numerous published scientific articles on venoms from snakes (Bothrops, Crotalus, and other genera), scorpions (Tityus sp), spiders (Phoneutria sp), their isolated toxins and natural...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Toxinology; Animal venoms; Toxins; Inhibitors; Homage; Giglio JR.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992007000400003

Partial characterization of digestive proteases in sheepshead, Archosargus probatocephalus (Spariformes: Sparidae)
Provedor de dados: 83
Autores: Merino-Contreras,María L.; Sánchez-Morales,Froylán; Jiménez-Badillo,María L.; Peña-Marín,Emyr S.; Álvarez-González,Carlos A.
ABSTRACT Digestive proteases were partially characterized in sheepshead juveniles, using biochemical and electrophoretic techniques. Results showed higher activity level of the stomach proteases (2.39 ± 0.02 U mg protein-1) compared to the intestinal proteases (1.6 ± 0.1 U mg protein-1). The activity of trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A was also recorded. The optimum temperature of the stomach proteases was recorded at 45 °C, while for intestinal proteases was recorded at 55 °C. Stomach proteases showed less stability to temperature changes than intestinal proteases. An optimum pH of 2 was recorded for stomach proteases with high stability under acidic conditions, while an optimum pH of 9 was recorded for intestinal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquaculture; Inhibitors; Pepsin; Proteases; Zymogram.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000400206

Comparative characterization of digestive proteases in redhead cichlid (Vieja melanurus) and twoband cichlid (Vieja bifasciata) (Percoidei: Cichlidae)
Provedor de dados: 83
Autores: Frías-Quintana,Carlos Alfonso; Peña-Marín,Emyr Saul; Ramírez-Custodio,Carlos David; Martínez-García,Rafael; Jiménez-Martínez,Luis Daniel; Camarillo-Coop,Susana; Guerrero-Zárate,Rocío; Asencio-Alcudia,Gloria Gertrudys; Álvarez-González,Carlos Alfonso.
ABSTRACT In the Southeast of Mexico, there are many native cichlids with commercial interest such as redhead cichlid (Vieja melanurus) and twoband cichlid (V. bifasciata), which have a great local demand and excellent meat quality. However, it is necessary to implement their culture based on nutrition studies and digestive biochemistry. This study’s objective was to characterize these two cichlids’ digestive proteases (pH, temperature, and inhibitors) through biochemistry techniques. Results showed that V. melanurus and V. bifasciata have a digestive capacity analogous to other omnivore fishes, where the optimal pH values of stomach proteases (4 and 2, respectively) and intestinal proteases (6 and 12, respectively), the optimal temperature of acid (35°C...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Inhibitors; PH; Proteases; Stability; Temperature.
Ano: 2021
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100210

Inhibitory Effects of Some Flavonoids on Thioredoxin Reductase Purified from Chicken Liver
Provedor de dados: 89
Autores: Türkoğlu,E.A; Kuzu,M; Ayasan,T; Inci,H; Eratak,SV.
ABSTRACT Thioredoxin reductases (TrxRs) are selenocysteine-containing flavoenzymes that reduce Trxin NADPH-dependent manner. In the view of the direct vital role of TrxR in a wide range of biochemical and physiological processes, methods to inhibit this enzyme are clinically important. TrxR has recently emerged as a new candidate in anticancer drug investigations because of overexpression in tumorous cells. In this study, TrxR from chick liver was purified 94.6-fold with a yield of 4.86% and a specific activity of 0.19 EU/mg. KM and Vmax values of TrxR for DTNB were calculated as 0.9 mM and 0,03 EU/mL, respectively. Then, the effects of the flavonoids hesperidin, naringenin, chlorogenic acid, ferulic acid, naringin, 3,4-dihydoxybenzoic acid, and ellagic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Flavonoids; Inhibitors; Natural products; Thioredoxin reductase.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2019000200345

Some Biochemical properties of polyphenoloxidase from spearmint (Mentha arvensis)
Provedor de dados: 52
Autores: Neves,Valdir Augusto; Picchi,Douglas Gatte; Silva,Maraiza Aparecida da.
Polyphenoloxidase (PPO; EC 1.14.18.1) extracted from Mentha arvensis leaves was isolated by (NH4)2SO4 precipitation and extensive dialysis. Its optimum pH and temperature varied with the substrate. The PPO showed activity with various diphenols. Km values were found 0.825, 0.928 and 7.41mM for caffeic acid, 4-methylcatechol and catechol, respectively. On heat-inactivation, half of the activity was lost after 60 and 15 sec at 70 and 75ºC, respectively. Measuring of residual activity showed a stabilizing effect of sucrose at various temperatures with activation energy (Ea) for inactivation increasing with sucrose concentration from 0 to 40% (w/w). Ea values of 78.13; 80.37; 82.79 and 81.00 kJ/Mol were found for 0, 15; 30 and 40% sucrose, respectively. PPO...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Polyphenoloxidase; Mentha arvensis; Characterization; Heat inactivation; Inhibitors.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000400025

Evaluation of antagonistic activity of milk fermented with kefir grains of different origins
Provedor de dados: 52
Autores: Santos,João Paulo Victorino; Araújo,Tatiane Ferreira; Ferreira,Célia Lúcia de Luces Fortes; Goulart,Simone Machado.
In this study, the potential of kefir grains, obtained from three different towns/cities in the Southeast Region of Brazil to inhibit the growth of the five pathogenic microorganisms was evaluated. The samples showed the growth inhibition from 42.80-69.15 for Staphylococcus aureus ATCC 6538, 30.73-59.89 for Escherichia coli ATCC 11229, 44.99-73.05 for Salmonela typhi ATCC 6539, 41.45-54.18 for Listeria monocytogenes ATCC 15313 and 70.38-86.80 for Bacillus cereus RIBO 1222-173-S4. These results indicated that the kefir grains evaluated had antagonistic activity toward the different pathogens tested. The ability to inhibit, although differently depending on the regional microbiota, indicated a potential for their use as a functional food.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Kefir; Antagonism; Inhibitors; Functional foods.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132013000500014

Enzymatic systems involved in D-limonene biooxidation
Provedor de dados: 52
Autores: Menéndez,Pilar; García,Carlos; Rodríguez,Paula; Moyna,Patrick; Heinzen,Horacio.
The biooxidation of limonene by an Aspergillus strain resulted in the production of perillyl alcohol and short chain fatty acids. Addition of ketoconazole, a known inhibitor of cytochrome P450 oxydase, eliminated the production of free acids, but did not affect biotransformation to perillyl alcohol.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Limonene; Biotransformation; Perillyl alcohol; Cytochrome oxydase; Inhibitors.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000200001

Fermentative hydrogen production from agroindustrial lignocellulosic substrates
Provedor de dados: 58
Autores: Reginatto,Valeria; Antônio,Regina Vasconcellos.
To achieve economically competitive biological hydrogen production, it is crucial to consider inexpensive materials such as lignocellulosic substrate residues derived from agroindustrial activities. It is possible to use (1) lignocellulosic materials without any type of pretreatment, (2) lignocellulosic materials after a pretreatment step, and (3) lignocellulosic materials hydrolysates originating from a pretreatment step followed by enzymatic hydrolysis. According to the current literature data on fermentative H2 production presented in this review, thermophilic conditions produce H2 in yields approximately 75% higher than those obtained in mesophilic conditions using untreated lignocellulosic substrates. The average H2 production from pretreated material...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fermentation; Hydrogen; Lignocellulosic substrates; Pretreatment; Inhibitors.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000200323

Preservatives and neutralizing substances in milk: analytical sensitivity of official specific and nonspecific tests, microbial inhibition effect, and residue persistence in milk
Provedor de dados: 65
Autores: Silva,Livia Cavaletti Corrêa da; Tamanini,Ronaldo; Pereira,Juliana Ramos; Rios,Edson Antônio; Ribeiro Junior,José Carlos; Beloti,Vanerli.
Milk fraud has been a recurring problem in Brazil; thus, it is important to know the effect of most frequently used preservatives and neutralizing substances as well as the detection capability of official tests. The objective of this study was to evaluate the analytical sensitivity of legislation-described tests and nonspecific microbial inhibition tests, and to investigate the effect of such substances on microbial growth inhibition and the persistence of detectable residues after 24/48h of refrigeration. Batches of raw milk, free from any contaminant, were divided into aliquots and mixed with different concentrations of formaldehyde, hydrogen peroxide, sodium hypochlorite, chlorine, chlorinated alkaline detergent, or sodium hydroxide. The analytical...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fraud; Formaldehyde; Hydrogen peroxide; Chlorinated compounds; Inhibitors.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782015000901613