Para determinar el porcentaje de remoción de cromo en la asociación alga-bacteria, se tomaron ejemplares del alga Bostrychia calliptera de pneumatóforos de Avicennia germinans y Rizophora mangle, en la desembocadura del Río Dagua, Pacífico colombiano. El ensayo se realizó in vitro en agua marina sintética a dos concentraciones de cromo 5 y 10mg/L, empleando biorreactores con cuatro tratamientos; i) material Alga-Bacteria (AB), ii) material algal con antibiótico Alga-antibiótico (AA), iii) consorcio bacteriano natural (CBN) y iv) control sin presencia de B. calliptera ni bacteria. Se monitoreó el comportamiento de poblaciones bacterianas y el porcentaje de disminución de cromo mediante AAS (Espectroscopía de absorción atómica). Se obtuvo diferencias significativas entre los tratamientos Alga-bacteria (AB) y el consorcio bacteriano natural (CBN), siendo Alga-bacteria más eficiente a 10mg/L (87%). El consorcio bacteriano natural CBN obtuvo mayor porcentaje de remoción a bajas concentraciones de cromo a 5ppm (62.85%). Los resultados mostraron una interacción positiva entre las bacterias asociadas (CBN) a la superficie del alga roja B. calliptera en su proceso acumulativo de cromo.

Water pollution is one of the most important environmental problems worldwide. Recently, biotechnology studies have oriented efforts to study algae-bacterium consortia with the aim to understand the mechanisms to find a possible solution in environmental sciences. This study determined the percentage of chromium removal by the alga-bacterium association exposed to a set of different chromium concentrations under controlled in vitro conditions. Wild plants of Bostrychia calliptera associated with bacterial populations were collected from Dagua River, Pacific coast of Colombia, and were monitored in the laboratory. The trial was conducted with synthetic seawater in bioreactors at two chromium levels: 5 and 10mg/L, and four different experimental treatments: i) algae-bacteria (AB), ii) algae with antibiotic (AA), iii) algal surface sediment, Natural Bacterial Consortium (CBN), and iv) the control without algae or bacteria. The experimental design followed a model of two factors (chromium concentration x combination types) with repeated measures using one factor. The microbial population behavior and the chromium concentration percentage were monitored by using atomic absorption spectroscopy (AAS). According to the data, Algae-bacteria (AB) treatment was the most efficient combination at 10mg/L (87%), whereas the bacterial consortia (CBN) was the most efficient at 5mg/L (62.85%). The results showed significant differences of chromium uptake between algae-bacteria (AB) and natural bacterial consortia (CBN), meaning the importance of those treatments in the chromium removal from coastal waters.

En este trabajo se evaluó la actividad antimicrobiana de dos extractos etanólicos de Propóleo (EEP) provenientes de apiarios de los municipios de Totoróy Buenos Aires en el Departamento del Cauca, frente a una bacteria Gram positiva y otra Gram negativa y se determinó la composición cualitativa de metabolitos secundarios de los dos extractos. La actividad bactericida se evaluó por el método de dilución en caldo y el análisis químico se realizó mediante pruebas de reacciones coloridas, cromatografía bidimensional y cromatografía de capa delgada. Ambos EEP mostraron efecto bactericida, donde el Propóleo de Buenos Aires fue más efectivo que el de Totoró frente a Pseudomonas aeruginosa, al inhibir su crecimiento a una concentración inferior (p<0,05), mientras que para Staphylococcus aureus el análisis estadístico no arrojó diferencias significativas (p>0,05) entre los dos extractos. El análisis químico reveló que ambos propóleos poseen flavonoides, alcaloides y cumarinas, entre otros, además que el Propóleo de Buenos Aires posee una mayor complejidad química, lo que sugiere la presencia de compuestos antibacterianos que pueden actuar eficientemente contra bacterias Gram positivas y Gram negativas.

In this study, we evaluated the antimicrobial activity of two Propolis ethanol extracts (EEP) from apiaries of municipalities Totoro and Buenos Aires in the Cauca deparment, against one Gram positive and one Gram negative bacteria and determined the qualitative composition of second metabolites the two extracts. Bactericidal activity was evaluated by the broth dilution method and phytochemical analysis was performed by color reaction, two-dimensional chromatography and thin layer chromatography. Both EEPs had a bactericidal effect, in which the Buenos Aires Propolis was more effective than the Totoro one against Pseudomonas aeruginosa, by inhibiting it's growth at a lower concentration (p<0.05), while for Staphylococcus aureus, statistical analysis showed no significant difference (p>0.05) between the two extracts. Chemical analysis showed that both were composed of flavonoids, alkaloids and coumarins, among others, and that the Buenos Aires Propolis had a greater chemical complexity, suggesting the presence of antibacterial compounds able to act effectively against Gram-positive and Gram negative bacteria.

Neste estudo, avaliouse a efeito antimicrobiano nós avaliamos a atividade antimicrobiana de dois extratos etanóicos de própolis (EEP) vindos de apiários dos municipios de Totoró e Buenos Aires no Departamento do Cauca, contra uma bactéria Gram positiva e Gram negativa e se determinou a composição qualitativa de metabólitos secundários dos dois extratos. A atividade bactericida foi avaliada pelo método de diluição em caldo e a análise química foi realizada por cromatografia em fase de teste, colorido bidimensional e cromatografia em camada delgada. Os resultados mostraram que os dois EEP tiveram um efeito bactericida, onde a própolis de Buenos Aires foi mais eficaz do que a de Totoró contra Pseudomonas aeruginosa, inibindo seu crescimento em menor concentração (p<0,05), enquanto que para Staphylococcus aureus a análise estatistica não mostrou diferença significativa (p>0,05) entre os dois extratos. A análise química mostrou que ambas as própolis estão compostas por flavonóides, alcalóides e cumarinas, entre outros, além demais, a própolis de Buenos Aires possui uma maior complexidade química, sugerindo a presença de compostos antibacterianos que podem atuar de forma eficaz contra as bactérias Gram positivas e Gram negativos.