Search Results

You are looking at 1 - 5 of 5 items for

  • Author: Adam Latała x
Clear All Modify Search
Open access

Sławomir Wierzba and Adam Latała

Evaluation of the enzymatic activity of selected bacterial strains

In these studies we attempted to evaluate the lipolytic, proteolytic and cellulolytic activity of bacterial strains isolated from water and the bottom sediments of Turawa Lake. The following bacterial genera prevailed among the isolated strains: Bacillus, Pseudomonas, Enterobacter, Cellulomonas and Cytophaga. The lipolytic activity was determined using a titrimetric method, the proteolytic activity — using a modified Anson method, and the cellulolytic activity - on the basis of mass decrement of a cellulose disk after 14 days of bacterial culture. The cultures were maintained at 28°C, pH 7.0 with the following substrates: olive oil, albumin and cellulose disk. Among the analysed microorganisms, Bacillus and Pseudomonas strains showed the highest lipolytic and proteolytic activity. In the cellulolytic assay Cytophaga bacteria showed about twofold higher activity than that of Celulomonas.

Open access

Adam Latała and Sławomir Wierzba

Biodegradation of bottom sediments of Turawa Lake

In this work we tested biopreparations developed in our laboratory for their ability to degrade the organic matter of the bottom sediments of Turawa Lake. The biodegradation was conducted under laboratory conditions for 6 weeks. For the testing purposes, there were three variants of biopreparations that contained autochthonous strains originating from our own collection and their mixture. The testing showed that the introduction of the biopreparations to the bottom sediment resulted in a significant increase of the number of bacteria, which consequently brought about the reduction of organic compounds in the sediment. In the case of all the variants, the number of bacteria increased by order of 102 - 104 CFU/g after 42 days of biodegradation. Among the tested biopreparations, the most effective one was the mixture of the autochthonous strains and those originating from the collection. After biopreparation was applied, a drop of content of carbohydrates by 66.94%, fatty matter by 83.33% and proteins by 74.42% was noted.

Open access

Sławomir Wierzba and Adam Latała

Biosorption lead(II) and nikel(II) from an aqueous solution by bacterial biomass

The optimum conditions for biosorption of Pb(II) and Ni(II) from aqueous solution were investigated, by using living and nonliving Pseudomonas fluorescens and Bacillus pumilus isolated from wastewater treatment plant. It was found that the optimum pH for Pb(II) removal by living and nonliving cells was 6.0, while 7.0 for Ni(II) removal. At the optimal conditions, metal ion biosorption was increased as the initial metal concentration increased. The binding capacity by living cells is significantly higher than that of nonliving cells at tested conditions. The maximum biosorption capacities for lead and nickel by using Ps. fluo-rescens and B. pumilus were 77.6, 91.4 and 65.1, 73.9 mg/g, respectively. The results of bio-sorption time and desorption experiments suggested that Pb(II) and Ni(II) uptake by the living bacterial biomass might be enhanced by intracellular accumulation.

Open access

Sylwia Śliwińska and Adam Latała

Abstract

Allelopathy may be one of the factors affecting the formation of massive and harmful algal blooms in aquatic environments. Recent studies indicate that blooms of cyanobacteria in the Baltic Sea has grown significantly in last decades, so it is important to determine the allelopathic interactions between the dominant species of cyanobacteria and microalgae. In this work we investigated the influence of allelopathic compounds on the growth of Skeletonema marinoi by addition of cell-free filtrate of the Baltic cyanobacterium Nodularia spumigena cultures grown under different temperature (15-25°C). Additionally the effects of filtrates of both an exponential and a stationary growing culture of N. spumigena were tested on diatom. These studies indicate that high temperature affected the donor species by increasing its production of allelochemicals. The highest drop of growth of analyzed diatom were observed after the addition of cell-free filtrate obtained from N. spumigena grown at 25°C and constituted 70% of their control. N. spumigena was only allelopathic in exponential growth phase, whereas the cyanobacteria filtrate from stationary phase have any effect on S. marinoi. These findings suggest that N. spumigena may reveal allelopathic activity and that the production of allelopathic substances is influenced by the temperature and growth phase of cyanobacteria.

Open access

Marek Klin, Zuzanna Kowalska, Filip Pniewski and Adam Latała

Abstract

The freshwater green microalga Scotinosphaera austriaca has been recorded from the brackish waters of the Gulf of Gdańsk (Baltic Sea). Morphological characters and genetic data were analyzed to confirm the taxonomic affiliation. This species bears features unusual in representatives of Ulvophyceae present in the Baltic Sea.