Author: Martín Antonio Pablo Moreno Pérez

Efecto de dietas monoespecíficas y mixtas en el crecimiento y supervivencia de larvas de camarón Litopenaeus vannamei (Boone, 1931)

Effect of monospecies and mixed diets on the growth and survivor of shrimp larvae Litopenaeus vanname (Bonne, 1931) 

Martín Pablo Antonio Moreno Pérez (2008)

El suministro de alimento vivo es uno de los principales problemas en la acuicultura del camarón debido a que durante las primeras etapas de vida suceden las mayores mortalidades. El objetivo de este trabajo fue evaluar el valor nutrimental de una dieta monoespecífica y mixta utilizando cultivos de dos especies de microalgas suministradas como alimento a larvas de camarón blanco (Litopenaeus vannamei). Se realizaron cultivos monoespecíficos por triplicado y no axénicos de Synechoccocus elongatus y Chaetoceros muelleri en sistemas en lotes sin recambio de medio de cultivo en frascos Erlenmeyer (150 ml) y Fernbach (2 l), que sirvieron como inóculo para cultivos semicontinuos en garrafones (15 l). En los cultivos se utilizó el medio “f” descrito por Guillard y Ryther (1962), temperatura de 20 ± 1 °C y luz continua a 100 μE m<sup>-2</sup> s<sup>-1</sup>. El porcentaje de dilución utilizado para los cultivos semicontinuos fue de 20% por día para S. elongatus y de 30% por día para C. muelleri. Durante la fase de estabilidad de los cultivos semicontinuos se evaluó la composición bioquímica de cada especie de microalga. Debido al menor tamaño de S. elongatus respecto al de C. muelleri, en todos los casos resultó una mayor densidad de células. En los cultivos de S. elongatus ocurrieron los mayores porcentajes de carbohidratos, peso orgánico seco y clorofila a. En tanto que en los cultivos de C. muelleri se presentó un mayor contenido de lípidos. Sin embargo, para ambas especies resultó un porcentaje igual de proteínas. El porcentaje total de aminoácidos esenciales y no esenciales resultó similar entre los cultivos monoespecíficos y mixtos. Para S. elongatus se encontró un mayor contenido de fenilalanina y alanina, pero los menores valores de cisteína. No se detectaron los ácidos grasos de la serie 22:6n3 (ácido docosahexaenóico: DHA) y 20:5n3 (ácido eicosapentaenóico: EPA) en S. elongatus, pero resultó un alto porcentaje de ácido linolénico (18:3n3). La tasa de crecimiento en las distintas etapas de vida de L. vannamei no tuvo diferencia por efecto del tipo de alimento suministrado en forma monoespecífica y mixta. Se encontró consumo preferencial de S. elongatus durante las distintas etapas de vida de L. vannamei. Esta tendencia fue análoga al utilizar las dietas mixtas de C. muelleri y S. elongatus. La supervivencia de L. vannamei fue similar al utilizar como alimento S. elongatus, C. muelleri o la mezcla de ambas especies. Se concluye que S. elongatus puede ser utilizada como alimento para la nutrición de etapas larvales de L. vannamei, ya que proporciona un valor nutrimental que permite obtener tasas de crecimiento y supervivencia similares a las obtenidas con C. muelleri.

The live food supply is one of the main problems in shrimp aquaculture because in the first live shrimp stages high mortalities have been recorded. Our objective was to evaluate the nutritional value of one monospecies and a mixed diet using cultures of two microalgae species as food for white shrimp larvae (Litopenaeus vannamei). The cultures were made in triplicate, axenic and monospecies, for Synechoccocus elongatus and Chaetoceros muelleri in progressively increasing volume starting from an Erlenmeyer flask (150 ml), then to Fernbach flask (2 l) that was used as inocula for the semicontinuous culture in a carboy (15 l). For maintenance of the cultures we used the “f” media of Guillard and Ryther (1962), a temperature of 20 ± 1 °C, and continuous light at 100 μE m<sup>-2</sup> s<sup>-1</sup>. The daily dilution percentage used for the semicontinuous cultures was 20% for S. elongatus and 30% for C. muelleri. During the stabilization stages of the semicontinuous cultures we measured the proximal composition of the microalgae. Because of the small cell size of S. elongatus compared to C. muelleri, all the cultures of S. elongatus had a higher cell density. In the S. elongatus cultures we obtained higher carbohydrate content, dry weight, and chlorophyll a content. The cultures of C. muelleri had a higher lipid content. Both species yielded a similar protein content. The total essential and nonessential amino acid content was similar between the monospecies and mixed cultures. In S. elongatus cultures we measured a high content of phenylalanine and alanine, but a lower content of cystein. In the S. elongatus cultures, we did not detect any fatty acid 22:6n3 (docosahecaenoic acid: DHA) and 20:5n3 (eicosapentaenoic acid: EPA), but did measure a high content of linolenic acid (18:3n3). The growth rates of the different live stages of L. vannamei were not significantly different when caused by food supplementation with the monospecies and mixed cultures. A preferential food intake was measured for the different life stages of L. vannamei and this trend was similar for both the monospecies diets and the mixed diet of C. muelleri and S. elongatus. The survival of L. vannamei was similar when any of the three diets was used. We concluded that S. elongatus can be used as food for the nutrition of larval stages of L. vannamei because this microalga provides a high nutritional value that yields growth rates and survival similar to those obtained with C. muelleri. 

Master thesis

Chaetoceros muelleri,Synechococcus elongatus,Larvas,Ciencias del mar BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA

Comparación de la efectividad de antibióticos genéricos de penicilina G benzatinica in vitro contra dos cepas de Staphylococcus aureus

Martín Antonio Pablo Moreno Pérez NINFA RAMIREZ DURAN MIGUEL ANGEL KARAM CALDERON YAZMIN CASTILLO SANCHEZ (2017)

Los medicamentos genéricos conllevan dudas acerca de su efectividad entre pacientes y profesionales. Se adquirieron los antibiótico penicilina benzatinica de 1,200,000 U de patentes y genéricos disponibles en el mercado, se evaluó su efectividad contra Staphylococcus aureus subsp. aureus (ATCC® 10832™) y Staphylococcus aureus (ATCC® 29213™) mediante el método de dilución en pozo. Resultados: No hubo diferencia entre el crecimiento de las dos cepas de S. aureus, pero si se encontró (p <0.05) entre las cepas expuestas a los cinco antibióticos. El antibiótico genérico Bencilpenicilina/procaína, Benzatina Bencilpenicilina (laboratorio AMSA) fue el que causó mayor inhibición del crecimiento de las dos cepas de S. aureus. Los costos de los medicamentos genéricos fueron hasta un 90 % menores comparado con el medicamento de patente Bencetazil combinado® (laboratorio Sandoz GmbH-TechOps).

Article

Antibióticos Genéricos Staphylococcus aureus BIOLOGÍA Y QUÍMICA

Molecular Identification of Mycobacterium Species of Public Health and Veterinary Importance from Cattle in the South State of México

ADRIAN ZARAGOZA BASTIDA NALLELY RIVERO PEREZ BENJAMIN VALLADARES CARRANZA KEILA ISAAC OLIVE Martín Antonio Pablo Moreno Pérez HORACIO SANDOVAL TRUJILLO NINFA RAMIREZ DURAN (2017)

Mycobacterium genus causes a variety of zoonotic diseases. The best known example is the zoonotic tuberculosis due to M. bovis. Much less is known about “nontuberculous mycobacteria (NTM),” which are also associated with infections in humans. The Mexican standard NOM-ZOO-031-1995 regulates the presence of M. bovis in cattle; however, no regulation exists for the NTM species. The objective of this study was to isolate and identify nontuberculous mycobacteria species from cattle of local herds in the south region of the State of Mexico through the identification and detection of the 100 bp molecular marker in the 23S rRNA gene with subsequent sequencing of the 16S rRNA gene.Milk samples (35) and nasal exudate samples (68) were collected. From the 108 strains isolated, 39 were selected for identification. Thirteen strains isolated from nasal exudates amplified the 100 bp molecular marker and were identified as M. neoaurum (six strains), M. parafortuitum (four strains), M. moriokaense (two strains), and M. confluentis (one strain). Except M. parafortuitum, the other species identified are of public health and veterinary concern because they are pathogenic to humans, especially those with underlying medical conditions.

Article

Mycobacterium Ocupational exposure nontuberculous mycobacteria cattle milk samples 23S RNA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Antagonistic properties of Micromycetes isolated from sinkholes of the Yucatán peninsula against phytopathogens

Propiedades antagonistas de micromicetos aislados de cenotes de la península de Yucatán contra hongos fitopatógenos

Martín Antonio Pablo Moreno Pérez MARIA MARCELA GAMBOA ANGULO GABRIELA PATRICIA HEREDIA ABARCA Blondy Beatriz Canto Canché MIGUEL ENRIQUE ROSADO VALLADO Irma Leticia Medina Baizabal RAUL TAPIA TUSSELL (2014)

In the search for natural alternatives to control fungal diseases, antagonistic fungi are valuable sources to find new models. In the present study, a total of 41 tropical micromycetes were isolated from plant debris submerged in sinkholes of the Yucatán Península. All strains were tested in antagonist assays against four phytopathogenic fungi (Colletotrichum gloeosporioides, Corynespora cassiicola, Curvularia sp. and Fusarium sp.). Results of the antagonistic assays showed mycelial growth inhibition (MCI ≥50 %) by 17 isolates (41 %) against at least one of the targets tested. The highest inhibition was exhibited by the Hypocrea lixii OSN-37 (MCI=61-77%) and Rhizoctonia solani OSE-73 (MCI=55-64%) strains against all targets while Pestalotiopsis mangiferae OH-02 (51-59%) caused inhibition on three of four pathogen strains. These three strains were cultured in fermented rice to obtain their ethyl acetate and methanol extracts which were tested against C. gloeosporioides using the microdilution assay. Results showed H. lixii OSN-37 and R. solani OSE-73 to be producers of antifungal metabolites as one of their modes of action. In conclusion, three promising antagonistic native strains were isolated from plant debris submerged in the Yucatán sinkholes, representing a valuable contribution to the development of ecofriendly alternatives to control fungal diseases in agriculture crops of the tropical regions.

Article

ANTAGONIST HYPOCREA LIXII MICROMYCETES PESTALOTIOPSIS MANGIFERAE SINKHOLE RHIZOCTONIA SOLANI BIOLOGÍA Y QUÍMICA BIOLOGÍA Y QUÍMICA

Atypical Klebsiella Species in a Third Level Hospital as Cause of Neonatal Infection

DAMIAN DAVID CIFUENTES CASTANEDA NINFA RAMIREZ DURAN ILIANA ESPINOZA RIVERA LUZ MARCELA CARO GONZALEZ Martín Antonio Pablo Moreno Pérez HUGO MENDIETA ZERON (2018)

Aportamos una propuesta para analizar la agresividad de un patógeno en relación a la resistencia y sensibilidad antimicrobianas encontradas.

Background: The opportunistic pathogen Klebsiella pneumoniae is one of the main causes of pediatric bacterial blood stream infections (BSI), which is complicated with sepsis and high mortality. Objectives: To identify atypical Klebsiella species affecting a sample of infected neonates with low antimicrobial response. Methods: Multidrug resistant blood cultures for Klebsiella from a Neonatal Service, were submitted to molecular identification by sequencing analysis of 16S ribosomal RNA. Results: Themean age of the newborns was 14.7±5.6 days. A total of 6 out of 8 cases were sepsis, 1 case of pneumonia, and 1 a catheterrelated infection. The molecular identification showed 3 cases of K. pneumoniae subsp. ozaenae, 2 of K. pneumoniae and K. variicola, and 1 case of K. oxytoca. The highest antimicrobial resistance was against cephalosporins and Trimethoprim/sulfamethoxazole. Conclusions: Klebsiella pneumoniae subsp. ozaenae was responsible for multidrug resistant strains of Klebsiella even in 37.5% of cases. In our clinical setting, the use of Amikacin and carbapenems are still useful to treat neonatal infections by Klebsiella even against K. variicola, which is the most resistant

Ciprés Grupo Médico S.C. (CGM).

Article

klebsiella neonatal infection atypical species MEDICINA Y CIENCIAS DE LA SALUD

Antimicrobial evaluation of extracts obtained from tropical micromycetes against phytopathogens

MARTIN PABLO ANTONIO MORENO PEREZ MARIA MARCELA GAMBOA ANGULO GABRIELA PATRICIA HEREDIA ABARCA BLONDY BEATRIZ CANTO CANCHE CECILIA MONICA RODRIGUEZ GARCIA Irma Leticia Medina Baizabal LETICIA PERAZA ECHEVERRIA (2016)

Nowadays, it is highly necessary to find more and safer agrochemicals. In this sense, micromycetes are an important source of natural products which could be used to control plant diseases. Therefore with the aims to contribute in this searching of natural products with antimicrobial applications, a total of 49 fungal strains were isolated from the Yucatan Peninsula. These fungi were cultured in fermented rice, their respective organic extracts macerated in ethyl acetate (EAE) and methanol (ME) were obtained and tested against five fungal pathogens of agricultural importance. These included Alternaria chrysanthemi, Colletotrichum gloeosporioides, Mycosphaerella fijiensis, and the bacteria Erwinia carotovora and Xanthomonas campestris using microdilution assays. The 69% of fungal extracts showed antifungal or antibacterial (2000 and 200 µg/mL, respectively) against at least one of the tested target. Strains Penicillium sp. OSE-61, Fusarium sp. OH2-30, Hypocrea lixii OSN-37 and Rhizoctonia solani OSE-73 showed activity against at least three of the five study pathogens. The most active EAE were partitioned, and its low (A), medium (B) polarity and precipitated (C) were obtained and assessed. The fraction A from Fusarium KS-15 displayed the lowest Minimum Inhibitory Concentration (MIC ≤25 µg/mL) and bactericide effect on X. campestris; fraction B of Penicillium sp. OSE-61 was relatively greater than the previous on A. chrysanthemi (MIC ≤500 µg/mL). Last fraction also exhibited good inhibitory effect on C. gloeosporioides. Finally, fraction B of H. lixii OSN-37 displayed promissory antifungal effect on C. gloeosporioides y M. fijiensis (MIC=1000 µg/mL). This research contributes to enrich the limited knowledge on the biological activity of native anamorphic fungi of the sinkholes of Yucatan and its potential use in biotechnological applications in agriculture.

Article

BIOASSAYS FUNGAL EXTRACTS FUSARIUM HYPOCREA MICROFUNGI BIOLOGÍA Y QUÍMICA