The benefit of bioaugmentation of activated sludge (AS) with yeasts was tested using AS and wastewaters (WW) that originated from the chemical industry, as well as synthetic WW. A stimulating effect of Saccharomyces cerevisiae on microbial respiration intensity in AS was shown. The added yeast biomass maintained viability in AS, an inhibitory effect of BAC on Bacilli was found; however, the addition of yeasts to AS reduced this effect.

The potential of aquatic plants to accumulate Cs may be of notable importance in the environmental monitoring of radioactive wastes. This study aimed to evaluate the accumulation of Cs-133 by freshwater macrophytes Bacopa amplexicaulis, Elodea densa, Ceratophyllum submersum, and Limnobium laevigantum after a 10-day incubation period with CsCl (1–1000 μM). The partitioning of Cs and other elements, including 21 metals, such as P, B, and As, was analyzed using inductively coupled plasma mass spectrometry combined with principal component analysis (PCA). The enzymatic activity of plant crude extracts and aquatic microorganisms was characterized. The transfer factor (TF) reached the highest values of 0.13 and 0.10 for C. submersum and L. laevigantum, respectively, at 1000 μM Cs. The TFs in the other sets were below 0.1. In the presence of Cs-133, there was a significant increase in dehydrogenase activity (p < 0.05) and a decrease in the activity of the Folin–Ciocalteu assay. A three-fold decrease in culturable microorganisms was found in plants with 1000 μM Cs. PCA analysis revealed the species-specific elemental distribution in plant biomass and the aquatic phase. A negative correlation between Na, Ca (2.0–2.5, PC1) and Mg, K, and P (−2, PC1) was found. Certain enzyme groups can serve as bioindicators of Cs pollution in aquatic ecosystems.

Quaternary ammonium compounds (QAC) are unique surfactants, which are widely used as biocides for numerous industrial purposes. An efficiency of disinfectant is highly dependent on the physicochemical properties of environment. The aim of this study was to evaluate the antibacterial effect of the widely used QACs, i.e. N,N-dimethyldodecan-1-amine oxide (DDAO) in mixture with the commercially available surface washing formulation (WF). Pseudomonas fluorescens served as a test organism. The changes in kinetic parameters of bacterial growth, optical density, ATP concentration in the batch cultures, as well as morphological changes of cells were monitored in order to evaluate a physiological response of bacterial cultures to the different combinations of the tested chemicals. A decrease of WF concentration in the broth from 0.1 % to 0.02 % resulted in a gradual reducing the lag period in the presence of 0.03 % DDAO, while the specific growth rate did not depend on the WF concentration. Comparison of the effect of ATP concentration and the OD620 has revealed the differences in cells response to the presence of WF and DDAO. It was concluded that the antibacterial effect of QACs, particularly DDAO, is highly dependent on the composition of washing formulations, which can notably reduce the efficiency of the added QACs.