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Tlajomulco de Zuniga, Mexico

Virgen-Ortiz J.J.,University of Colima | Ibarra-Junquera V.,University of Colima | Osuna-Castro J.A.,University of Colima | Escalante-Minakata P.,University of Colima | And 2 more authors.
Analytical Biochemistry | Year: 2012

One of the recurrent methodological problems in preparative biochemical work is the concentration of dilute protein solutions, including culture supernatants resulting from biotechnological processes. A procedure was developed to concentrate enzymes by a novel cryoconcentration system. This approach includes a new device that facilitates the sample freezing and the subsequent solute elution from the frozen matrix by centrifugation. The optimal centrifugation conditions for this cryoconcentration system were obtained using whey protein solution as a model. The procedure was applied to concentrate dilute solutions of commercial pectinase, measuring the endopolygalacturonase (EPG) activity of this enzyme in the concentrate by a method based on the on-line torque measurement, and of recombinant fructan:fructan 1-fructosyltransferase (1-FFT) protein of Pichia pastoris from a culture in a bioreactor, as an expression system. The optimal centrifugation speed, time, and temperature were 6150 g, 20 min, and 4 °C, respectively. The concentration factors for the dilute protein solutions were 9.2-, 11.2-, and 17.1-fold for 1-FFT, whey, and commercial pectinase, respectively. Recoveries ranged from 87% to 93%. The procedure allowed concentrating proteins efficiently without affecting their enzymatic activity. © 2012 Elsevier Inc. All rights reserved. Source

Virgen-Ortiz J.J.,University of Colima | Ibarra-Junquera V.,University of Colima | Escalante-Minakata P.,University of Colima | Osuna-Castro J.A.,University of Colima | And 3 more authors.
Analytical Biochemistry | Year: 2013

This work presents a rapid and simple freeze centrifugation method to concentrate dilute protein solutions for detection by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) Coomassie blue staining. Moreover, a simple way to assemble a cryoconcentration device is presented, and its use is discussed. Commercial purified protein standard and an enzyme with high fructosyltransferase (FTase) activity, coming from target fractions obtained by chromatographic separation, were used as an example. FTase, coming directly from the chromatographic fractions, was difficult to view through SDS-PAGE analysis; however, it was easily visualized, and its activity was enhanced, after the application of the freeze centrifugation protocol presented here. © 2013 Elsevier Ltd. All rights reserved. Source

Vega-Ramos K.L.,Azul Agricultura y Servicios S.A. de C.V. | Uvalle-Bueno J.X.,Azul Agricultura y Servicios S.A. de C.V. | Gomez-Leyva J.F.,Tlajomulco Jalisco Institute of Technology
Biochemical Genetics | Year: 2013

In this study, 115 isolates of Fusarium oxysporum from roots of Agave tequilana Weber cv azul plants and soil in commercial plantations in western Mexico were characterized using morphological and molecular methods. Genetic analyses of monosporic isolates included restriction enzyme analysis of rDNA (ARDRA) using HaeIII and HinfI, and genetic diversity was determined using Box-PCR molecular markers. Box-PCR analysis generated 14 groups. The groups correlated highly with the geographic location of the isolate and sample type. These results demonstrate the usefulness of ARDRA and Box-PCR techniques in the molecular characterization of the Fusarium genus for the discrimination of pathogenic isolates. © 2013 Springer Science+Business Media New York. Source

Valenzuela-Zapata A.G.,Signo Tequila Foundation | Lopez-Muraira I.,Tlajomulco Jalisco Institute of Technology | Gaytan M.S.,University of Utah
Ethnobiology Letters | Year: 2011

The Mexican sport of charrería, or Mexican rodeo, developed in post-conquest Mexico as a way of preserving and celebrating traditional cowboy riding and livestock handling skills. Today, charrería is considered the national sport of Mexico and the charro (cowboy) is also a celebrated icon of Mexicanness. Special handcrafted ropes used in charrería, known as sogas finas, or charro lariats, are made from the fibers of the Agave inaequidens. The manufacture of charro ropes is an artisinal practice that requires both cultural and botanical knowlege. In the last ten years, there has been a significant decline in the A. inaequidens population in the Cerro Viejo mountain range of the central-western Mexican state of Jalisco, putting the financial wellbeing of local lariat artisans at risk. Drawing on fieldwork and laboratory analysis conducted from 2002 through 2010, we discuss the socio-cultural significance of charro lariats, detail the harvesting of A. inaequidens in relation to lariat craftsmanship, document the physical characteristics of the A. inaequidens from this region, and describe the relationship between traditional knowledge and the local economy. The goal of this research is two-fold: 1) to stimulate feedback between producers and consumers in an attempt to leverage the existing business cluster based on traditional knowledge and 2) to initiate dialogue concerning conservation, domestication, and sustainable management of the wild A. inadequidens population. © 2011 Society of Ethnobiology. Source

Iniestra-Gonzalez J.J.,University of Colima | Lino-Lopez G.J.,University of Colima | Paull R.E.,University of Hawaii at Manoa | de la Rosa A.P.B.,San Luis Potosi Institute of Scientific Research and Technology | And 6 more authors.
Postharvest Biology and Technology | Year: 2013

Papaya fruit ripening processes involve the coordinated action of several hydrolases that causes cell wall degradation. Endoxylanase participates in xylan or arabinoxylan modifications and its importance has been related to papaya softening. However, endoxylanase has been not fully characterized biochemically and kinetically. Semipurified endoxylanase from ripe 'Maradol' papaya fruit had an optimal temperature from 45°C to 50°C, a pH optimum of 5.5 against Remazol brilliant blue-xylan (RBB-Xylan) and enzymatic activity remained stable during 36h at 45°C. The activation energy of the enzyme was 25.5kJmol-1, and the Vmax at 32, 37 and 42°C was 788.9, 888.9 and 1085.6μgkg-1s-1, respectively. The Km did not change as a function of temperature and was measured as 1.8gL-1 and was within the range reported for other xylanases. Total proteins were extracted from color-break, half-ripe and ripe fruit. A pre-endoxylanase at 63.9kDa was identified in the color-break fruit and an active endoxylanase at 32.5kDa that was only found in ripe fruit, when the highest enzymatic activity was obtained. Immunodetection on two-dimensional gel electrophoresis (2DE) protein blots showed three isoforms of the pre-endoxylanase at color-break and ripe stages and, four isoforms in ripe fruit that were absent in color-break fruit. The biochemical and kinetic characteristics of the endoxylanase are crucial to our understanding papaya fruit softening. © 2013 Elsevier B.V.. Source

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