Sugar esters are bioactive compounds derived from renewable resources. They consist of a sugar moiety with attached non-polar part – usually a fatty acid. These compounds find uses in cosmetic, food and pharmaceutical industries as surfactants due to their physicochemical and antimicrobial activities. In this study we have produced fatty acids for sugar ester synthesis from bacterially derived polyesters, namely polyhydroxyalkanoates (PHAs). We have developed methodology to decorate PHA monomers with a fluorinated moiety. With aid of biocatalysis a series of glucose esters was created with unmodified and modified PHA monomers. All synthesised compounds showed moderate antimicrobial activity.

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This study shows microbiological contamination of water in two main Podhale rivers, whose resources are used for the production of artificial snow, and the resulting snow contamination. Thirty-one E. coli strains were isolated from snow at two ski stations in the studied region, their antimicrobial resistance was determined, and the presence of extended spectrum β-lactamase (ESBL) genes was searched for. The results indicate that the waters of both rivers are severely contaminated, resulting in the contamination of artificial snow with, among others, thermotolerant E. coli. E. coli isolated from snow were most frequently resistant to ampicillin (74.19%) and amoxicillin/clavulanate (51.61% isolates). Aminoglycosides and third generation cephalosporins were most efficient among the tested antimicrobials. Some bacterial strains were multidrug resistant and three strains exhibited the ESBL mechanism. Molecular analyses showed the presence of ESBL genes in the same three strains. Genetic variation among E. coli indicates that only some genotypes are able to survive the artificial snow production process.

Mountain regions in Poland are among the most frequently visited tourist destinations, causing a significant anthropogenic pressure put on the local rivers. In this study, based on numbers of 9 microorganisms, content of 17 antibiotics and 17 physicochemical parameters, we determined a pollution gradient in six sites along Białka, a typical mountain river in southern Poland. The E.coli/Staphylococcus ratio varied evidently between polluted and non-polluted sites, indicating that the possible utility of this parameter in assessing the anthropogenic impact on river ecosystems is worth further investigation. Then, using next generation sequencing, we assessed the changes in bacterial community structure and diversity as a response to the pollution gradient. Proteobacteria and Bacteroidetes were the most abundant phyla in the majority of samples. Actinobacteria were the most abundant in the most pristine (groundwater) sample, while Firmicutes and Verrucomicrobia were more prevalent in polluted sites. Bacterial diversity at various levels increased with water pollution. Eleven bacterial genera potentially containing pathogenic species were detected in the examined samples, among which Acinetobacter, Rhodococcus, and Mycobacterium were the most frequent. At the species level, Acinetobacter johnsonii was most prevalent potential pathogen, detected in all surface water samples, including the pristine ones. Two bacterial taxa—genus Flectobacillus and order Clostridiales showed very distinct variation in the relative abundance between the polluted and non-polluted sites, indicating their possible potential as biomarkers of anthropogenic impact on mountain river waters.