Legionella pneumophilla bacteria in thermal saline bath.

OBJECTIVE: The study was aimed at determining whether Legionella pneumophila bacteria can be found in thermal saline waters used in balneotherapy. METHODS: Water samples were collected from three thermal saline baths, supplied by thermal saline waters (type Cl - Na). The total number of bacteria was determined in the direct microscopic count under a fluorescence microscope The numbers of bacteria belonging to different phylogenetic groups (Eubacteria, Legionella sp. and Legionella pneumophila) were determined with the use of a molecular FISH method. RESULTS: The highest average total number of bacteria as well as the highest average number of Eubacteria in the entire research cycle was recorded in bath 1. Bacteria belonging to the Legionella genus along with Legionella pneumophila were identified in all water samples collected from each bath. Moreover, biofilm containing cells of L. pneumophilla was identified in the collected water samples. CONCLUSION: The number of bacteria in water increases with the bath's age. The Legionella pneumophila can successfully develop not only in fresh water bodies but in thermal saline baths as well. Still, it is uncertain whether the commonly applied culture method, developed for freshwater bodies, is also suitable for thermal saline baths.

Extracellular enzyme activity in a willow sewage treatment system.

This paper presents the results of studies on the activity of extra-cellular enzymes in soil-willow vegetation filter soil which is used in the post-treatment of household sewage in an onsite wastewater treatment system located in central Poland. Wastewater is discharged from the detached house by gravity into the onsite wastewater treatment system. It flows through a connecting pipe into a single-chamber septic tank and is directed by the connecting pipe to a control well to be further channelled in the soil-willow filter by means of a subsurface leaching system. Soil samples for the studies were collected from two depths of 5 cm and 1 m from three plots: close to the wastewater inflow, at mid-length of the plot and close to its terminal part. Soil samples were collected from May to October 2009. The activity of the extra-cellular enzymes was assayed by the fluorometric method using 4-methylumbelliferyl and 7-amido-4-methylcoumarin substrate. The ranking of potential activity of the assayed enzymes was the same at 5 cm and 1 m soil depths, i.e. esterase > phosphmomoesterase > leucine-aminopeptidase > ß-glucosidase > α-glucosidase. The highest values of enzymatic activity were recorded in the surface layer of the soil at the wastewater inflow and decreased with increasing distance from that point.

Influence of the root system of the Common Osier (Salix viminalis L.) on abundance of heterotrophic bacteria in the willow sewage treatment system.

The impact of the Common Osier (Salix viminalis L.) root system on number (CFU) of heterotrophic bacteria and their production in a soil-willow filter was examined. The Osier rhizosphere was found to be suitable habitat for growth of the examined microbial group, and the root system stimulated development of heterotrophic bacteria. The rhizosphere bacteria to control soil bacteria (R:C) ratio oscillated between 2.48 and 2.75 depending on the location of sample collection. The highest abundance of bacteria as well as highest bacterial production was observed at location I, near sewage discharge onto the plot. There was a significant positive correlation between the number of heterotrophic bacteria and the bacterial production.

Occurrence and activity of microorganisms in shrimp waste.

This study aimed to determine the occurrence and respiration activity of heterotrophic bacteria and fungi in shrimp shell waste and to evaluate the role of chitinolytic bacteria and fungi in its decomposition. The highest levels of bacteria were found in shrimp heads sections and the lowest in exoskeletons. The level of fungi was much lower, with the highest proportion present in heads sections and the lowest in exoskeletons. Chitinolytic bacteria constituted a small percentage of the total heterotrophic bacteria in fresh shrimp waste, averaging 4% in exoskeletons, 2.4% in all parts, and 2% in heads. No chitinolytic bacteria were detected in stored waste. In contrast, the percentage of chitinolytic fungi in shrimp waste was much higher than that of bacteria. Chitinolytic fungi constituted 25-60% of the total fungi in fresh waste and 15-40% in stored waste. Chitinolytic bacteria isolated from heads sections were characterized by the highest chitinolytic activity, averaging 11.2 nmol of methylumbelliferyl x mg(-1) protein x h(-1), whereas the lowest activity was in strains from exoskeletons, averaging 3.2 nmol of methylumbelliferyl x mg(-1) protein x h(-1). The chitinolytic activity of fungi isolated from all parts waste, head sections, and exoskeletons was similar. The respiration activity of microorganisms in fresh and stored waste was similar. Oxygen consumption activity increased during incubation and approached a saturation value between days 4 and 5. No correlation between the end value of respiratory activity in the analyzed section of shrimp discard after 5 days and the level of bacteria and fungi was observed. The only significant correlation observed was between the respiratory activity of the shrimp and the level of fungi. The respiration activity significantly depended on the analyzed section of shrimp discard (p<0.000).