Effect of nonionic surfactants on Rhizopus homothallicus lipase activity: A comparative kinetic study

Abstract

Background and Aims: T. gondii is a causal agent of encephalitis in immunocompromised patients. Pyrimethamine (PYR) has been the treatment of choice for toxoplasmosis. The aim of this study was to analyze the effect of nitazoxanide and pyrimethamine on astrocytes infected with T. gondii invitro. Methods: Rat astrocytes were cultured and infected with T. gondii. The effect of nitazoxanide (10, 20 and 30 ?g/mL) and pyrimethamine (7, 10 and 13 ?g/mL) on astrocytes infected was evaluated at 24 and 48 h post-infection. Tachyzoites and astrocytes were detected by the immunocytochemical method. T. gondii viability in astrocytes infected and treated with NTZ and PYR as well as NTZ and PYR citotoxicity on astrocytes in vitro were evaluated by the MTT assay. Results: The number of parasites in astrocytes treated with the drugs was significantly reduced when compared to control (p <0.001) at 24 and 48 h. Nitazoxanide produced 97% T. gondii death in a concentration of 10 ?g/mL in 48 h infected astrocytes. At 48 h, the death rate of T. gondii was higher when treated with nitazoxanide than with pyrimethamine. A higher toxicity rate in astrocyte was observed when using pyrimethamine at 40 ?g/mL. Conclusions: Nitazoxanide reduced T. gondii infection more efficiently than pyrimethamine and is not cytotoxic to astrocytes at the administered dose. " 2013 IMSS.",,,,,,"10.1016/j.arcmed.2013.07.002",,,"http://hdl.handle.net/20.500.12104/40969","http://www.scopus.com/inward/record.url?eid=2-s2.0-84885154526&partnerID=40&md5=9c480cda80220d78facc189ae6e22aa0",,,,,,"6",,"Archives of Medical Research",,"415

421",,"44",,"Scopus",,,,,,"Astrocytes; Effect; Nitazoxanide; Pyrimethamine; Toxoplasma infection",,,,,,"Effect of nitaxozanide and pyrimethamine on astrocytes infected by toxoplasma gondii in vitro",,"Article" "42749","123456789/35008",,"Rivera-Reyes, J.G., Instituto Tecnológico de Roque, km 8 Carretera Celaya, Guanajuato, Mexico; Peraza-Luna, F.A., Instituto Tecnológico de Tlajomulco de Zúñiga, Km 10 Carretera Tlajomulco-San Miguel Cuyutlan, Tlajomulco de Zúñiga, Jalisco, Mexico; Serratos-Arévalo, J.C., Instituto Tecnológico de Tlajomulco de Zúñiga, Km 10 Carretera Tlajomulco-San Miguel Cuyutlan, Tlajomulco de Zúñiga, Jalisco, Mexico; Posos-Ponce, P., Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Carretera a Nogales Km. 15.5, Las Adjuntas Nextipac, Jalisco, Mexico; Guzmán-Maldonado, S.H., Celaya, Campo Experimental Bajío INIFAP, Km. 6.5 Carretera Celaya-San Miguel Allende, Guanajuato, Mexico; Cortez-Baheza, E., Instituto Tecnológico de Roque, km 8 Carretera Celaya, Guanajuato, Mexico; Castañón-Nájera, G., Universidad Juárez Autónoma de Tabasco, División Académica de Ciencias Biológicas, Carretera Villahermosa-Cárdenas, km. 0.5, entronque Bosques de Saloya, Villahermosa, Tabasco, Mexico; Mendoza-Elos, M., Instituto Tecnológico de Roque, km 8 Carretera Celaya, Guanajuato, Mexico",,"Rivera-Reyes, J.G.

Peraza-Luna, F.A.

Serratos-Arevalo, J.C.

Posos-Ponce, P.

Guzman-Maldonado, S.H.

Cortez-Baheza, E.

Castanon-Najera, G.

Mendoza-Elos, M.",,"2009",,"Oats cereal is a worldwide significant crop. It is grown in restrictive climates and in rainy regions of temperate areas. Cultivation of oats produces high forage yields and grain quality, which gives it a wide variety of uses as animal feed and human food. However, the physiological quality of oat seeds in Mexico faces problems, which impact both their import and export. Phytic acid concentration in the oat seed plays a very important role since it affects seed viability, its germination capacity and potential seedling vigor. The objective of this study was to determine the effect of chemical fertilization on the phytic acid concentration and vigor of oat seeds. The study was conducted at the Technological Institute of Roque (ITR) and the National Research Institute for Forestry, Agricultural and Livestock in Celaya, Guanajuato in 2004 and 2005. Effects of two factors were evaluated at four levels each. Factor A was nitrogen fertilization (60, 100, 140, and 180 kg/ha). Factor B was phosphorus fertiliza ion (40, 80, 120 and 160 kg/ha). Variables measured were phytic acid, protein and amino acid concentrations, and vigor of oat seeds. Results indicated a cubic effect from nitrogen fertilization, and a quadratic effect from phosphorus fertilization, on the phytic acid concentration of oat seeds. The same trends were observed in seed vigor. However, there were no statistical differences in protein concentration for any of the study factors. Amino acid and phytic acid concentrations were not significantly related.",,,,,,,,,"http://hdl.handle.net/20.500.12104/40970","http://www.scopus.com/inward/record.url?eid=2-s2.0-75449090852&partnerID=40&md5=bf9cffd02f7b40f905b6f6332101eded",,,,,,,,"Phyton",,"37

42",,"78",,"Scopus

WOS",,,,,,"Nitrogen; Oat; Phosphorus; Phytates; Quality",,,,,,"Effect of nitrogen and phosphorus fertilization on phytic acid concentration and vigor of oat seed (var. Saia) in Mexico [Efecto de la fertilización nitrogenada y fosforada en el contenido de ácido fático y vigor de la semilla de avena de la variedad Saia en México]",,"Article" "42750","123456789/35008",,,,"Vázquez,Luis Bernardo

MedellÍn,Rodrigo A.

Cameron,Guy N.",,"2000",,,,,,,,"doi: 10.1644/1545-1542(2000)0812.0.CO;2; 15",,"0022-2372","http://hdl.handle.net/20.500.12104/40971","http://dx.doi.org/10.1644/1545-1542(2000)081<0077:PACEOS>2.0.CO;2",,,,"American Society of Mammalogists",,"1",,"Journal of mammalogy",,"77

85",,"81",,"BioOne",,,,,,,,,,,,"POPULATION AND COMMUNITY ECOLOGY OF SMALL RODENTS IN MONTANE FOREST OF WESTERN MEXICO",,"Journal Article" "42752","123456789/35008",,"Diaz, J.C.M., Groupe de Biocatalyse et Chimie Fine, University de la Mediterranie, Marseille, France; Cordova, J., Laboratorio de Bioprocesos, Universidad de Guadalajara, Guadalajara, Mexico; Baratti, J., Groupe de Biocatalyse et Chimie Fine, University de la Mediterranie, Marseille, France; Carriere, F., Laboratoire d'Enzymologie Interfaciale et de Physiologie de la Lipolyse, UPR 9025, CNRS, Marseille, France; Abousalham, A., Laboratoire d'Enzymologie Interfaciale et de Physiologie de la Lipolyse, UPR 9025, CNRS, Marseille, France, GERME S.A., Marseille, France",,"Diaz, J.C.M.

Cordova, J.

Baratti, J.

Carriere, F.

Abousalham, A.",,"2007",,"Based on amino-terminal sequencing and mass spectrometry data on the Rhizopus homothallicus lipase extracted using solid (SSF) and submerged state fermentation (SmF) methods, we previously established that the two enzymes were identical. Differences were observed, however, in terms of the specific activity of these lipases and their inhibition by diethyl p-nitrophenyl phosphate (E600). The specific activity of the SSF lipase (10,700 ?mol/min/mg) was found to be 1.2-fold that of SmF lipase (8600 ?mol/min/mg). These differences might be the result of residual Triton X-100 molecules interacting with the SSF lipase. To check this hypothesis, the SmF lipase was incubated with submicellar concentrations of Triton X-100. The specific activity of the lipase increased after this treatment, reaching similar values to those measured with the SSF lipase. Preincubating SSF and SmF lipases with E600 at a molar excess of 100 for 1 h resulted in 80% and 60% enzyme inhibition levels, respectively. When the SmF lipase was preincubated with Triton X-100 for 1 h at a concentration 100 times lower than the Triton X-100 critical micellar concentration, the inhibition of the lipase by E600 increased from 60% to 80%. These results suggest that residual detergent monomers interacting with the enzyme may affect the kinetic properties of the Rh. homothallicus lipase. " 2007 Humana Press Inc. All rights of any nature whatsoever reserved.