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Interacción de los hongos entomopatógenos Beauveria bassiana y Metarhizium anisopliae con insecticidas en larvas de Spodoptera frugiperda

MARIBEL RIVERO BORJA (2015)

Tesis (Maestría en Ciencias, especialista en Entomología y Acarología).- Colegio de Postgraduados, 2015.

Con intención de mejorar el control de Spodoptera frugiperda (gusano cogollero) se probaron combinaciones de insecticidas con hongos sobre larvas de tercer ínstar de esa plaga. Se usaron combinaciones de las CL50 de clorpirifós etil y spinosad (0.24 y 0.025 g mL-1, respectivamente) con suspensiones de esporas de aislamientos de Beauveria bassiana (Bb88) y Metarhizium anisopliae (ETL) (1x108 esporas mL-1) en tres secuencias de aplicación: hongo seguido (a las 24 h) de insecticida; hongo simultáneo con insecticida e insecticida seguido de hongo. Como respuesta se observó la mortalidad de las larvas tratadas y la esporulación de los cadáveres. En la mortalidad influyeron los tres factores: insecticidas, los hongos y la secuencia. En general, bajo las combinaciones se obtuvieron mortalidades similar a las de los testigos de insecticida, pero se aumentó la esporulación, implicando que los hongos infectaron más huéspedes cuando se aplicaron en combinación con los insecticidas que cuando se aplicaron solos (P<0.0001). Spinosad fue mejor promotor de la infección (esporulación) que clorpirifós etil. La secuencia Bb88-spinosad (aplicación simultánea) produjo mayor mortalidad que su testigo de insecticida. El aislamiento Bb88 fue antagónico con clorpirifós etil respecto a la mortalidad cuando el hongo se aplicó antes o simultáneamente con el insecticida. Se discute el potencial de las combinaciones de hongos con insecticidas para mejorar el desempeño de los hongos entomopatógenos, el papel de las secuencias en ese desempeño y las posibles causas del antagonismo observado entre Bb88 y clorpirifós etil. _______________ INTERACTION OF ENTOMOPATHOGENIC FUNGI Beauveria bassiana AND Metarhizium anisopliae WITH INSECTICIDES IN LARVAE OF Spodoptera frugiperda. ABSTRACT: Aiming to improve control of Spodoptera frugiperda (fall armyworm), combinations of insecticides with fungi were tested against third instar larvae of this pest. Combinations of the LC50 of ethyl chlorpyrifos and spinosad (0.24 and 0.025 g mL-1, respectively) were used with suspensions of spores from isolates of Beauveria bassiana (Bb88) and Metarhizium anisopliae (ETL) (1x108 spores mL-1) in three application sequences: fungus followed (24 h later) by insecticide, fungus and insecticide simultaneously, and insecticide followed by fungus. The response observed was mortality of the treated larvae and sporulation on cadavers. The three factors, insecticides, fungi and the sequence, influenced mortality. In general, the combinations achieved mortalities similar to those of the insecticide controls, but sporulation increased, meaning that the fungi infected more hosts when they were applied in combination with the insecticides than when they were applied alone (P<0.0001). Spinosad was a better promotor of infection (sporulation) than ethyl chlorpyrifos. The sequence Bb88-spinosad (simultaneous application) produced higher mortality than its insecticide control. The Bb88 isolate was antagonistic with chlorpyrifos in terms of mortality when the fungus was applied before or simultaneously with the insecticide. We discuss the potential of fungus-insecticide combinations for better performance of entomopathogenic fungi, the role of the sequence in their performance and the possible causes of the antagonism observed between Bb88 and chlorpyrifos.

Master thesis

Secuencias de aplicación Esporulación Gusano cogollero Clorpirifós etil Spinosad Hongos entomopatógenos Antagonismo Application sequences Sporulation Fall armyworm Ethyl chlorpyrifos Entomopathogenic fungi Antagonism Entomología y Acarología Maestría CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Atmósferas modificadas en modalidad de microperforado, enterobacterias y residuos de plaguicidas en nopal verdura (Opuntia ficus indica L)

NORA MERAZ MALDONADO (2012)

Tesis (Doctorado en Ciencias, especialista en Entomología y Acarología).- Colegio de Postgraduados, 2012.

El nopal verdura es una hortaliza que aporta cantidades importantes de nutrimentos a la dieta en México. Sin embargo, cuando éste es usado como producto mínimamente procesado, la vida de anaquel se limita a los cambios en coloración de la piel y heridas pero, también debe ser considerada, dentro de la calidad, la inocuidad relacionada a la contaminación química y microbiológica. El presente estudio aborda éstos aspectos en seis capítulos que tienen por objetivos: 1) Determinar la predilección del consumidor en la adquisición de nopal verdura por tamaño, color, presentación, acidez y fibra. 2) Evaluar algunos cambios en la calidad por efecto del tamaño en nopal verdura entero desespinado. 3) Determinar el efecto de las atmósferas modificadas en la calidad de nopal verdura entero desespinado. 4) Evaluar la aplicación de ac. ascórbico, ac. ascórbico + ac. fumárico y ac. ascórbico + ac. málico y cloro (testigo), en la calidad y preservación de nopal verdura entero desespinado. 5) Medir la sobrevivencia y crecimiento de Salmonella sp y Escherichia coli en nopal verdura troceado, tratado con cloro, ac. ascórbico y agua destilada estéril. 6) Evaluar el efecto del lavado en la reducción de los residuos de malatión y clorpirifós etílico. El nopal verdura de 12-17 cm de longitud es preferido en un 70% por los consumidores. La clorofila se correlacionó directamente con el tamaño de los cladodios. Los nopales de 5.0-10.5 cm son susceptibles a mayores pérdidas de peso. Las atmósferas modificadas con 15 microperforaciones preservaron mejor la apariencia del nopal verdura a 4 ± 2°C. La aplicación de cloro y/o ac. ascórbico disminuyó el cambio de color de los tejidos. El ac. ascórbico tendió a disminuirlos niveles de Salmonella sp y E. coli en nopal verdura troceado, pero no erradicó a las bacterias. El lavado redujo en más de 90% la presencia de malatión en nopal verdura a las 24 horas de aplicación. _______________ MODIFIED ATMOSPHERES IN THE MICRO PERFORATED MODE, BACTERIA GROWTH AND PLAGUICIDES RESIDUES IN VEGETABLE NOPAL (Opuntia ficus indica L.). ABSTRACT: Nopal is a vegetable that provide important amount of nutriments to diet on México. However, when nopal is used as a minimally processed product some concerns appear such as the shelf life, which is short and it is limited by the discoloration of the skin and wounds but, into the quality, the safety by chemical y microbiological pollution must also be included. These topics were addressed in this study, which was divided in six chapters with the following objectives: 1) To determine the consumer preference when acquiring nopal considering size, color, presentation, acidity and fiber by. 2) To evaluate quality changes according to the size of integer and free of thorns nopal leaves. 3) To determine the effect of modified atmospheres on integer and free of thorns nopal leaves. 4) To determine the effect of ascorbic acid, ascorbic acid + fumaric acid, ascorbic acid + malic acid and chlorine as a witness, in the quality of nopal leaves, which were integer and free of thorns. 5) To measure the survival and growth of Salmonella sp and E. coli in nopal leaves minimally processed treated with chlorine, ascorbic acid and sterile water. 6) To evaluate the effect of washing in reducing the residues of malathion and chlorpyrifos ethyl. The preferred nopal leaves size by consumers in 70% of the cases is for those between 12 and 17 cm. Chlorophyll content is directly proportional to nopal leaves size. Vegetable nopals of 5 to 10.5 cm long are susceptible to greater weight loss. Modified atmospheres with 15 microperforations better preserved nopal appearance at 4 ± 2 ° C. Application of chlorine and/or ascorbic acid decreased the enzymatic darkening and cold damage in vegetable nopal. Ascorbic acid tended to decrease the levels of Salmonella sp and E. coli in chopped nopal, but it did not eradicate the bacteria. Washing decreased by more than 90% the presence of malathion in vegetable nopal, analyzed 24 hours after its application.

Doctoral thesis

Opuntia ficus-indica Atmósferas modificadas Salmonella Escherichia coli Malatión Clorpirifos etílico Entomología y Acarología Doctorado Modified atmospheres Malathion Chlorpyrifos ethyl CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

ACETYLCHOLINESTERASE INHIBITION AND MICRONUCLEUS FREQUENCY IN OYSTERS (CRASSOSTREA CORTEZIENSIS) EXPOSED TO CHLORPYRIFOS

ALMA BETSAIDA BENITEZ TRINIDAD YAEL YVETTE BERNAL HERNANDEZ IRMA MARTHA MEDINA DIAZ MARIA DE LOURDES ROBLEDO MARENCO BRISCIA SOCORRO BARRON VIVANCO DELIA DOMINGUEZ OJEDA CARLOS ALBERTO ROMERO BAÑUELOS MANUEL IVAN GIRON PEREZ AURORA ELIZABETH ROJAS GARCIA CRISTINA LIZBETH MORENO HERNANDEZ (2014)

Chlorpyrifos (CPF) is an Organophosphorous pesticide (OP) that has been widely used for both agricultural and domestic pest control. To date, there is little information regarding the effects of this pesticide on aquatic organisms, particularly oysters. The aim of this study was to evaluate Acetylcholinesterase (AChE) activity and Micronucleus (MN) frequency in the oyster Crassostrea corteziensis in laboratory exposure with CPF (20, 40, 60, 80, and 160 µg/L) and in a field study. The results showed that AChE was reduced 60 - 82 % in oysters exposed to CPF, relative to the negative control. Similar AChE results were observed in oysters collected from the Boca de Camichín Estuary in Nayarit, Mexico; with respect to genetic damage, evaluated through MN, treatment with CPF did not induce the MN frequency, nor did the oyster from the field study exhibit an increase in this biomarker. These results suggest that C. corteziensis is a sensitive model for evaluating the acute toxicity of OP in laboratory studies as well in the field. In addition, it generates prospects on studying mechanisms through which the oyster could possess resistance to genotoxic agents, as well as its being a reliable model for evaluating the genotoxic effects of xenobiotics through the MN technique.

El clorpirifos (CPF) es un pesticida organofosforoso (OP) que ha sido ampliamente utilizado tanto para el control de plagas agrícolas como domésticas. Hasta la fecha, hay poca información sobre los efectos de este pesticida en los organismos acuáticos, particularmente las ostras. El objetivo de este estudio fue evaluar la actividad de la acetilcolinesterasa (AChE) y la frecuencia del micronúcleo (MN) en la ostra Crassostrea corteziensis en exposición de laboratorio con CPF (20, 40, 60, 80 y 160 μg / L) y en un estudio de campo. Los resultados mostraron que la AChE se redujo de 60 a 82% en ostras expuestas a CPF, en relación con el control negativo. Se observaron resultados similares de AChE en las ostras recolectadas en el estuario de Boca de Camichín en Nayarit, México; Con respecto al daño genético, evaluado a través de MN, el tratamiento con CPF no indujo la frecuencia MN, ni la ostra del estudio de campo mostró un aumento en este biomarcador. Estos resultados sugieren que C. corteziensis es un modelo sensible para evaluar la toxicidad aguda de OP en estudios de laboratorio, así como en el campo. Además, genera perspectivas sobre el estudio de mecanismos a través de los cuales la ostra podría poseer resistencia a los agentes genotóxicos, así como su ser un modelo fiable para evaluar los efectos genotóxicos de los xenobióticos a través de la técnica MN.

Article

acetylcholinesterase micronucleus Crassostrea corteziensis chlorpyrifos CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

EFFECT OF CHLORPYRIFOS ON THE IMMUNE RESPONSE OF NILE TILAPIA (OREOCHROMIS NILOTICUS)

KARINA JANICE GUADALUPE DIAZ RESENDIZ MANUEL IVAN GIRON PEREZ (2014)

The objective of this study was to evaluate the effect of chlorpyrifos, an organophosphate pesticide, on immune response parameters of Nile tilapia (Oreochromis niloticus). The results indicated that chlorpyrifos (0.051, 0.102 and 0.255 mg L-1) did not provoke significant changes in the proliferation capacity of lymphocytes of tilapia; however, at 0.051 mg L-1, this pesticide induced a diminishment in concentration of lgM in plasma. On the other hand, organisms exposed to high concentration of the pesticide showed an increase in the lysozyme activity compared to control fish.

El objetivo de este trabajo fue evaluar el efecto de clorpirifos, un plaguicida organofosforado, sobre parámetros de la respuesta inmune de tilapia nilótica (Oreochromis niloticus). Los resultados indicaron que clorpirifos (0.051, 0.102 y 0.255 mg L-1) no provocó cambios significativos en la capacidad de proliferación de linfocitos de tilapia; sin embargo, a la concentración de 0.051 mg L-1, este plaguicida indujo una disminución de la concentración de IgM en plasma. Por otra parte, los organismos expuestos a altas concentraciones del plaguicida, mostraron un incremento en la actividad de lisozima en comparación con peces control.

Article

Chlorpyrifos nile tilapia immunotoxicity Clorpirifos inmunotoxicidad Tilapia nilótica CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Caracterización de bioaerosoles emitidos en biofiltros durante el tratamiento de COV´s por citometría de flujo

ANA BETSABE FLORES BARBOZA (2018)

"Se monitoreó y evaluó un sistema de biofiltración alimentado con vapores de acetato de etilo y tolueno por 180 días. Durante este periodo se estudiaron los efectos de la variación de carga y paros de alimentación de un contaminante sobre la capacidad de eliminación y la emisión de bioaerosoles. A la par, se montó un sistema control alimentado únicamente con aire del compresor y empacado con perlita sin inocular y sin alimentación de contaminantes. Se obtuvieron muestras de bioaerosoles a la entrada y salida de ambos sistemas con un muestreador Impinger AGI-30. Los bioaerosoles se caracterizaron por conteo en placa y por citometría de flujo (CMF) con dos fluorocromos: Naranja de Tioazol (TO) y Yoduro de Propidio (PI) que tiñen células vivas y muertas respectivamente, obteniendo separación por viabilidad y conteo celular. En la segunda etapa del proceso de biofiltración de acetato de etilo y tolueno, se alimentaron 108 g m-3 h-1 de contaminantes presentando, una eficiencia de remoción de acetato de etilo de ~100% y de tolueno de ~80%. Durante esta etapa, la concentración de bioaerosoles medida por citometría de flujo mostró un máximo de emisión de 1.2x107 células/m3 comparado con 1.8x103 UFC/m3 obtenida por conteo en placa, indicando una diferencia de 4 órdenes de magnitud. Conforme avanzó el tiempo de operación, aumentó el número de UFC contabilizado por cultivo en placa y en la mayoría de los casos la salida presentó mayores concentraciones que la entrada, comprobando que el sistema emite más bioaerosoles cultivables en comparación de los que hay en el aire de entrada. En CMF no se observó una relación entre el tiempo transcurrido y la concentración de bioaerosoles, la mayor emisión se registró al momento de aumentar la carga de 54 a 108 g m-3 h. La concentración de bioaerosoles fue disminuyendo lentamente conforme se alcanzó la estabilidad del biofiltro y en los periodos donde se tenía una alta remoción de contaminantes. Se comprobó la capacidad del biofiltro control como un sistema que retiene bioaerosoles, la concentración de bioaerosoles disminuyo en las tres primeras etapas de 2x103 a 3x102 UFC/m3 en el biofiltro control, cuando se contabilizó por conteo en placa. Por CMF se observó una disminución en la concentración en las dos primeras etapas siendo más notoria en la etapa 2 al día 62 de operación, de 7x106 a 3.5x106 células/m3."

"A biofiltration system fed with ethyl acetate and toluene vapors was monitored and evaluated. During this period, the effects of load and shutdown of a contaminant on the elimination capacity and emission of bioaerosols were studied. At the same time, a control system was installed, fed only with air from the compressor and packed with pearlite without inoculating and without contaminants. Samples of bioaerosols were obtained at the entrance and exit of both systems with an Impinger AGI-30. The bioaerosols were characterized using Petri dishes and flow cytometry (CMF) with two fluorochromes: Thioazole Orange (TO) and Propidium Iodide (PI) that stain living and dead cells respectively, obtaining separation by viability and cell count. The second stage of the biofiltration process showing removal efficiency of ~100 and ~ 80% for ethyl acetate and toluene respectively and the maximum concentration emitted from bioaerosol was 1.2x107 célls/m3 using flow cytometry whit respect to 1.8x103 CFU/m3 obtained by plate count, indicating a difference of 4 orders of magnitude. As the operating time increased, the number of CFUs recorded using plate culture increased and in most cases the output had higher concentrations than the entrance, proving that the system emits more bioaerosols compared to those in the air of entry. The capacity of the control biofilter was checked as a system that retains bioaerosols, the concentration of bioaerosols decreased in the first three stages from 2x103 to 3x102 CFU/m3 in the control biofilter using plate count. Using CMF, a decrease in concentration was observed in the first two stages. In conclusion, it was demonstrated that the biofiltration system can be a source of emission or retention of bioaerosols, depending on the operating conditions and characteristics of the air. The CMF showed to be a suitable and very promising xvii technique that allows the study of bioaerosols not only in biofilters, but it can be used in any environment."

Master thesis

Bioaerosol Flow Cytometry Fluorochrome Ethyl acetate Toluene Biofilter CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Temporal and longitudinal biofilm matrix analysis of a biofilter treating ethyl acetate during ozonation

ITZEL COVARRUBIAS GARCIA AITOR AIZPURU SONIA LORENA ARRIAGA GARCIA (2018)

"The present paper focuses on the biofilm composition and pattern of biomass in gas biofiltration of ethyl acetate working under continuous addition of ozone (O3). Two biofilters were operated for 230 days, one under continuous addition of O3 (90 ppbv) and another one without. Throughout the operation time, the extracellular polymeric substances (EPS), the main components in the extracellular matrix (ECM), were extracted from the biofilm and characterized qualitatively using Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) and quantitatively by analyzing its main constituents: carbohydrates, proteins, and glucuronic acid. To date, EPS characterization has been attempted mainly with biofilm aggregates related to water treatment, not air biofiltration. The results of this study may be helpful and provide more information about EPS structure when O3 was added. O3 addition only affected the amount of EPS and not its composition. The greater effect was observed on carbohydrate content since it is the main component in EPS. The EPS/biomass ratio measured was twice lower with O3 addition. Higher removal efficiency (RE) and mineralization rates were obtained with the biofilter subjected to O3 addition, and a smaller volume of a reactor would be necessary to treat all contaminant under this condition. EPS content is only quantitatively reduced by O3 addition, and at the low O3 concentration applied, no structural alteration is noted regarding the composition of the EPS."

Article

Extracellular polymeric substances Ozone Biomass composition Ethyl acetate Biofiltration Longitudinal behavior INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS INGENIERÍA Y TECNOLOGÍA DEL MEDIO AMBIENTE INGENIERÍA Y TECNOLOGÍA DEL MEDIO AMBIENTE

Physicochemical, mechanical, and biological properties of bone cements prepared with functionalized methacrylates

ROSSANA FARIDE VARGAS CORONADO JUAN VALERIO CAUICH RODRIGUEZ (2004)

Bone cements prepared with methyl methacrylate (MMA) as a base monomer and either methacrylic acid (MAA) or diethyl amino ethyl methacrylate (DEAEMA) as comonomers were characterized in terms of curing behavior, mechanical properties, and their in vitro biocompatibility. The curing time and setting temperature were found to be composition dependent while the residual monomer was not greatly affected by the presence of either acidic or alkaline comonomers in the bone cements. For samples with MAA comonomer, a faster curing time and higher setting temperature were observed when compared to the cement with DEAEMA comonomer. In terms of mechanical properties, the highest compressive strength was exhibited by formulations containing MAA, while the highest impact strength was shown by the formulations prepared with DEAEMA. There were no differences observed between the two formulations for tensile, shear, and bending strength values. Similarly, fatigue crack propagation studies did not reveal differences with the addition of either DEAEMA or MAA. No differences were observed in the initial number of attached primary rat femur osteoblasts on the different bone cements and positive controls. However, after 48h there was a reduced proliferation in the cells grown on bone cements containing MAA.

Article

 BIOCOMPATIBILITY BONE CEMENTS DIETHYL AMINO ETHYL METHACRYLATE MECHANICAL PROPERTIES METHACRYLIC ACID OSTEOBLASTS INGENIERÍA Y TECNOLOGÍA

Flourensia cernua: Hexane extracts a very active mycobactericidal fraction from an inactive leaf decoction against pansensitive and panresistant Mycobacterium tuberculosis

GLORIA MARIA MOLINA SALINAS Luis Manuel Peña Rodríguez BENITO DAVID MATA CARDENAS Fabiola Escalante Erosa DIMNA SILVIA GONZALEZ HERNANDEZ VICTOR MANUEL TORRES DE LA CRUZ HERMINIA GUADALUPE MARTINEZ RODRIGUEZ Salvador Said_Fernández (2011)

The efficacy of decoction in extracting mycobactericidal compounds from Flourensia cernua (Hojasé) leaves and fractionation with solvents having ascending polarity was compared with that of (i) ethanol extraction by still maceration, extraction with a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration, followed by fractionation with n-hexane, ethyl acetate, and n-butanol; (ii) sequential extraction with n-hexane, ethyl acetate, and n-butanol, by still maceration, using a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration. The in vitro mycobactericidal activity of each preparation was measured against drug-sensitive (SMtb) and drug-resistant (RMtb) Mycobacterium tuberculosis strains. The results of which were expressed as absolute mycobactericidal activity (AMA). These data were normalized to the ΣAMA of the decoction fraction set. Although decoction was inactive, the anti-RMtb normalized ΣAMA (NAMA) of its fractions was comparable with the anti-RMtb NAMA of the still maceration extracts and significantly higher than the anti-SMtb and anti-RMtb NAMAs of every other ethanol extract and serial extract and fraction. Hexane extracted, from decoction, material having 55.17% and 92.62% of antituberculosis activity against SMtb and RMtb, respectively. Although the mycobactericidal activity of decoction is undetectable; its efficacy in extracting F. cernua active metabolites against M. tuberculosis is substantially greater than almost all pharmacognostic methods.

Article

ACETIC ACID ETHYL ESTER ALCOHOL BUTANOL FLOURENSIA CERNUA DECOCTION HEXANE SOLVENT UNCLASSIFIED DRUG BIOLOGÍA Y QUÍMICA QUÍMICA BIOQUÍMICA ALCALOIDES ALCALOIDES