Tolerance Tests of Alcaligenes faecalis BW1 Extract.

Aims: To highlight whether metabolites of Alcaligenes faecalis BW1 extract can be administered orally for their possible antimycobacterial effects. Study Design: Study of the influence of certain parameters on the extract of Alcaligenes faecalis by using either discs or well diffusion methods against M. smegmatis. Place and duration of study: Laboratory of Microbial Biotechnology, Department of Biology, Faculty of Sciences and Technical, University Sidi Mohamed Ben Abdellah, BP 2202, Road of Immouzer, Fez, Morocco. From April to August, 2012. Methodology: The impact of acidic pH of gastric juice, bile, hydrogen peroxide, pancreatic enzymes and lysozyme on the antimycobacterial activity of Alcaligenes faecalis BW1 extract was evaluated by agar diffusion method. Detection whether or not antibacterial metabolites having a synergistic effect with rifampicin against M. smegmatis was also explored. Results: Antibacterial metabolites of Alcaligenes faecalis BW1 extract resist to the action of gastric pH, gallbladder bile and hydrogen peroxide. In addition, they are not affected by pancreatic enzymes and lysozyme. Moreover, they have a synergistic effect with rifampicin against M. smegmatis. Conclusion: Anti-mycobacterial metabolites of Alcaligenes faecalis BW1 extract are compatible with rifampicin and could be administered orally as antitubercular agents after their purification, identification in further work.

The Effect of Temperature on Nitrate and Phosphate Uptake from Synthetic Wastewater by Selected Bacteria Species.

Aim: The aim of this study was to ascertain the effect of temperature on nutrient uptake ability of four bacterial species. Methodology: A total of four bacterial species (Klebsiella sp., Pseudomonas sp., Lysinibacillus sp. and Staphylococcus sp.) were used for the study. The media used for the investigation was synthetic wastewater. Four different temperatures (25ºC, 30ºC, 35ºC and 40ºC) were used for the investigation. The study was carried out under shake flasks conditions. Immediate after inoculation with the respective test bacterial species and every 24 h for a 96 h incubation time, aliquot wastewater samples were removed from the flasks for the estimation of total phosphate, nitrate, pH and growth rate, using standard procedures. Results: The results revealed phosphate and nitrate removal ranges of 10.84 % to 55.55 % and 90.67 % to 97.27 %, respectively in the presence of the Klebsiella sp. In the presence of the Pseudomonas sp, Lysinibacillus sp. and Staphylococcus sp., phosphate removals ranges of 0.36 % to 46.98 %, 11.89 % to 50.80 % and 2.74 % to 51.21 % were observed, respectively. For nitrate concentrations, removal levels that ranged from 2.19 % to 92.95 %, 0.97 % to 23.12 % and 7.56 % to 91.66 % were observed in the presence of Pseudomonas sp, Lysinibacillu ssp. and Staphylococcus sp., respectively. All the test bacterial species showed some measure of efficiency in phosphate removal. For nitrate removal, the Lysinibacillus sp. did not exhibit remarkable nitrate removal ability at any of the temperatures. In addition, the optimum temperatures for phosphate removals were observed to be 30ºC to 40ºC for the Klebsiella sp. and Pseudomonas sp; and 30ºC to 35ºC for the Lysinibacillus sp. and Staphylococcus sp. For nitrate removal, optimum temperatures for removal were observed to be 25ºC to 40ºC, for the Klebsiella sp and 25ºC to 35ºC, for the Pseudomonas sp. and Staphylococcus sp. Conclusion: The study was able to reveal the optimum temperatures for phosphate and nitrate uptake in synthetic wastewater by the test bacterial species.

Factores involucrados en la translocación bacteriana en un modelo experimental de obstrucción intestinal / Involucrate factors in bacterial translocation in a experimental model of intestinal obstruction

Se deseño un modelo experimental de obstrucción intestinal (OI) a fin de estudiar las alteraciones histológicas a nivel de la pared intestinal y nódulos linfáticos mesntéricos (NLM). Para tal efecto se utilizaron 32 ratas Sprague-Darley las cuales bajo anestesia con tiopental sódico les fue practicada una laparotomía + ligadura del íleon con seda 3-0 causando oclusión completa de su luz. A diferentes intervalos de producirse la OI (24, 48, 72 y 96 horas), posterior a su sacrificio mediante dislocación cervical se analizaron histológicamete los diferentes grupos. A las 24 horas post OI se apreció congestión y edema de la pared intestinal, presencia de infiltrado celular inflamatorio a nivel de la lámina propia y reactividad de los NLM. A las 48 horas se incrementó el edema y la congestión, se evidenció fragmentación de la mucosa y translocación fragmentación de la mucosa y translocacióy translocación de bacterias a través de ella, las cuales alcanzaron los nódulos linfáticos de la pared. A nivel de los NLM la histiocitosis era mayor. La constatación de TB en la OI amplía aún más el conjunto de alteraciones observadas en esta patología donde no sólo se produce la absorción de productos tóxicos y endotoxinas a nivel del segmento comprometimento y que pudiesen explicar la bacteriemia y la sepsis en este tipo de pacientes

Actividad antibiótica de bacterias marinas ante bacterias patógenas de humanos / Antibiotic activity of marine bacteria against human pathogenic bacteria

Se analizó la capacidad de inhibición de bacterias marinas productoras de sustancias antibacterianas ante bacterias patógenas en humanos, por medio de técnicas de antibiosis directa. Los resultados mostraron que algunas bacterias eran capaces de inhibir el crecimiento de ciertas bacterias patógenas en humanos