Evalúa los actinomicetos de origen marino productoras de metabolitos secundarios con actividad antimicrobiana por su capacidad inhibitoria contra patógenos multidrogorresistentes (MDR) de origen clínico. Los actinomicetos fueron aislados de sedimento marino (Bahía de Ancón – Lima y Bahía de Independencia – Ica) y de esponjas de orillas intermareales de Pucusana (Lima) y Marcona (Ica). El aislamiento se realizó en Agar Czapeck Dox, Agar Marino y Agar Almidón Caseína. En un tamizaje primario se evaluó la actividad antibacteriana de 62 actinomicetos de sedimento marino; el 50% (31) mostraron actividad inhibitoria sobre Staphylococcus aureus 457, 59% (36) a Pseudomonas aeruginosa 657 y 37% (23) a ambos patógenos. Cepas seleccionadas del primer tamizaje, fueron evaluadas frente a cepas estándar MDR y otros patógenos Gram negativos, Gram positivos y Candida albicans, todos de ...

This study was undertaken in order to assess the use of somatic coliphages as faecal pollution indicators in recreational seawater. In 140 samples from 5 beaches at the “Costa Verde” circuit, Lima, somatic coliphages were enumerated and correlated with conventional faecal pollution indicators (Faecal coliforms, E. coli and enterococci). After sample treatment with the “Sample Filtration” modified technique, somatic coliphages were assayed by the “Single-Agar-Layer” method using the strain E. coli C ATCC 13706 as the bacterial host. Faecal coliforms (FC) E. coli (EC) and enterococci (EN) were enumerated by the Most Probable Number method. In the statistical analysis, we took into account faecal pollution levels based on arbitrary values such as <1000 CF/100 mL (“Low pollution”) and 1000 FC/100 mL (“High pollution”). The beaches surveyed showed faecal pollution level...

This study was undertaken in order to assess the use of somatic coliphages as faecal pollution indicators in recreational seawater. In 140 samples from 5 beaches at the “Costa Verde” circuit, Lima, somatic coliphages were enumerated and correlated with conventional faecal pollution indicators (Faecal coliforms, E. coli and enterococci). After sample treatment with the “Sample Filtration” modified technique, somatic coliphages were assayed by the “Single-Agar-Layer” method using the strain E. coli C ATCC 13706 as the bacterial host. Faecal coliforms (FC) E. coli (EC) and enterococci (EN) were enumerated by the Most Probable Number method. In the statistical analysis, we took into account faecal pollution levels based on arbitrary values such as <1000 CF/100 mL (“Low pollution”) and 1000 FC/100 mL (“High pollution”). The beaches surveyed showed faecal pollution level...

The presence of Plesiomonas shigelloides causing enteric disease in tilapia Oreochromis niloticus in a fish farm in Lima region, Peru is reported. The bacteria were isolated and identified as Plesiomonas shigelloides by conventional biochemical techniques and confirmed by the API 20NE system (numerical profile 7162744 that ratifies 99.3% P. shigelloides). Strains evaluated (n=4) had a fermentative metabolism of glucose, test positive to cytochrome oxidase, indole, Voges-Proskauer and methyl red. The most frequent external signs were erythema in abdomen and pectoral fins, and prominent and reddened anus with bloody discharge. Internally, ascites in visceral cavity and gut inflammation were detected. Histopathology studies revealed edema of the lamina propia and epithelial necrosis of gastric and intestinal tissue, and necrosis in anterior kidney and gonad.

En el presente trabajo se reporta la presencia de Plesiomonas shigelloides causando un cuadro patológico entérico en tilapia Oreochromis niloticus en una piscigranja de la región Lima, Perú. Las bacterias fueron aisladas e identificadas por técnicas bioquímicas convencionales y confirmadas por el sistema API 20NE (perfil numérico 7162744 que ratifica a P. shigelloides al 99.3%). Las cepas evaluadas (n=4) presentaron un metabolismo fermentativo de glucosa, positividad en las pruebas de citocromo oxidasa, indol, Voges-Proskauer y rojo de metilo. Los signos externos más frecuentes de la enfermedad fueron eritema en el vientre y las aletas pectorales, ano prominente y enrojecido con descarga sanguinolenta. Internamente se observó el intestino inflamado y la presencia de líquido ascítico en la cavidad visceral. El estudio histopatológico reveló edema de la lámina propia y necros...

Objective. To evaluate the in vitro antimicrobial activity of marine actinomycete strain 13A-2 against enterobacteria producing P-lactamases isolated from patients with urinary tract infections. Material and Methods. Using the technique of double layer actinomycete is selected with the highest antagonistic activity against 16 Enterobacteriaceae Klebsiella sp., Proteus sp. and E. coli, beta-lactamase-producing patients with urinary infection Maternal Perinatal Institute of Lima. The strain 13-A2, isolated from a marine sponge collected from the Peruvian coast, was identified molecularly by amplification of the gene encoding 16S rRNA the peptidic nature of the antimicrobial was determined by techniques Bradford, Qubit fluoremeter, SDS-PAGE and HPLC. It managed to quantify the production of antimicrobial using a new culture medium proposed by the author which was compared with marine broth.

Objective. To evaluate the in vitro antimicrobial activity of marine actinomycete strain 13A-2 against enterobacteria producing P-lactamases isolated from patients with urinary tract infections. Material and Methods. Using the technique of double layer actinomycete is selected with the highest antagonistic activity against 16 Enterobacteriaceae Klebsiella sp., Proteus sp. and E. coli, beta-lactamase-producing patients with urinary infection Maternal Perinatal Institute of Lima. The strain 13-A2, isolated from a marine sponge collected from the Peruvian coast, was identified molecularly by amplification of the gene encoding 16S rRNA the peptidic nature of the antimicrobial was determined by techniques Bradford, Qubit fluoremeter, SDS-PAGE and HPLC. It managed to quantify the production of antimicrobial using a new culture medium proposed by the author which was compared with marine broth.

Potato (Solanum tuberosum L.) is the fourth most consumed food crop in the world, whose production in Peru is diminished due to phytosanitary problems and high costs of chemical fertilizers. In the present work, 32 actinomycetes isolated from the rhizosphere of organic native potato crops collected in the town of Cabana, Lucanas, Ayacucho, were characterized phenotypically and evaluated for their in vitro antagonistic capacity against Oomycete phytopathogen Phytophthora infestans. The characterization tests showed that 97% of the actinomycetes were able to assimilate glucose, sucrose, and mannitol; as well as producing extracellular enzymes like amylases (100%) and cellulases (50%). Furthermore, the growth in laboratory culture was better in the range of pH 5.5-8.5 and temperature 28-30 °C. From the tests of antagonism in oat agar (71.9%) and rye agar (31.2%), three strains were selecte...

El cultivo de la papa se ve afectado por una gran cantidad de patógenos que disminuyen su calidad y productividad. Uno de los métodos de control de estos fitopatógenos es mediante el uso de microorganismos antagonistas, en especial aquellos que se aíslan de la comunidad microbiana presente en la rizósfera. En este trabajo, se aislaron 49 cepas de actinomicetos y se evaluaron sus capacidades antagonistas frente a fitopatógenos que afectan a Solanum tuberosum. El 26.5% presentó capacidad antagónica frente a Pectobacterium carotovorum, el 69.4% a Fusarium sp., el 44.9% a Lasiodiplodia sp., el 55.1% a Rhizoctonia solani y el 46.9% a Phytophthora infestans. Cultivos de dos actinomicetos seleccionados (AND 12 y AND 24) fueron tratados con acetato de etilo, diclorometano, hexano y butanol, cuyos extractos crudos mostraron actividad antimicrobiana, siendo el extracto obtenido con acetato...