Due the importance of lactic acid bacteria (LAB) in Colombia and worldwide, it has been necessary to optimize the culture conditions using different kind of substrates to increase growth. In this research, cane molasses was exploited as an indicator substrate to determinate Lactobacillus plantarum growth. Different conditions and variables that affect the microbial development were evaluated. L. plantarum (WS417) was used as a control strain, inoculating diverse sterile molasses concentrations at different pH values, temperature and agitation. The strain growth was evaluated by traditional microbiology, direct bacteria count, seeded in MRS agar plates. Relationships between biomass and effectiveness of different culture conditions were estimated by factorial variance analysis, showing the results as optimal growth conditions the content of 20% cane molasses, 30±1°C for 24 hours, pH 5,2±0,1, and 100rpm with counts of 43x10 9 UFC/mL. It was concluded that cane molasses could be employed as growth substrate for Lactobacillus sp.

RESUMENObjetivo. Caracterizar la diversidad microbiana y calidad microbiológica e higiénico sanitaria de diferentes marcas de jamones de cerdo cocidos abombados y no abombados comprados en varios supermercados de Bogotá D.C. Materiales y métodos. Se analizaron 10 marcas diferentes de jamones de cerdo cocidos comprados en tres supermercados, refrigerados bajos las mismas condiciones del consumidor, durante 45 días. Se realizó los recuentos en placa de microorganismos de interés en la industria de alimentos y de inocuidad en las muestras con o sin distensión del empaque e identificación por pruebas bioquímicas y PCR para determinar la diversidad de la microbiota. Se aislaron cepas productoras de biopelículas provenientes de la superficie de una planta de alimentos de una de las marcas de los jamones investigadas. Resultados. Se identificaron un total de 139 cepas aisladas del producto terminado, de las cuales un 99% (137 cepas) pertenecen al grupo de Bacterias Acido Lácticas (BAL), el 1% restante son levaduras. De las 31 cepas aisladas de las superficies en la zona de tajado, el 97% (30 cepas) presentaron formación de biopelículas. Se determinó ausencia de patógenos tanto en el producto terminado como en las muestras de las superficies. Conclusiones. El deterioro causado por abombamiento del empaque fue asociado a la presencia de BAL, debido a que fueron encontradas en la zona de tajado y en el producto terminado, de este último únicamente se aislaron BAL, en mayor proporción cepas correspondientes al género de Lactobacillus sp.Palabras clave: Bacterias acido lácticas, jamón cocido, biopelículas. 2078 ORIGINALRev. MVZ Córdoba 15(2):2078-2086

The environmental isotopes are a tool for interpreting the hydrological processes related to underground environments. These are used for the validation of hydrogeological models, in terms of recharge, transit and discharge zones, as well as the identification of groundwater interactions with other water bodies and groundwater residence time in the hydrogeological units. The determination of the recharge processes have usually been validated from knowledge about the stable isotopes present in the water molecule (18O and 2H). At the regional level, this evaluation has been addressed through the construction of isoscapes combined with an understanding of the hydrological characteristics present in the study area and knowledge of conceptual hydrogeological models. The objective of this study is to apply a scheme for the analysis of potential groundwater recharge zones, from 18O and 2H spatial variability in precipitation, baseflow and groundwater, using spatial modelling tools. Based on a preliminary work done for the Antioquia department, a strategic area was chosen in which the results are more forceful and have greater implications in groundwater management: the Aburrá Valley-Colombia.