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The Pseudomonas sp. P-1 strain, isolated from heavily petroleum hydrocarbon-contaminated soil, was investigated for its capability to degrade hydrocarbons and produce a biosurfactant. The strain degraded crude oil, fractions A5 and P3 of crude oil, and hexadecane (27, 39, 27 and 13 % of hydrocarbons added to culture medium were degraded, respectively) but had no ability to degrade phenanthrene. Additionally, the presence of gene-encoding enzymes responsible for the degradation of alkanes and naphthalene in the genome of the P-1 strain was reported. Positive results of blood agar and methylene blue agar tests, as well as the presence of gene rhl, involved in the biosynthesis of rhamnolipid, confirmed the ability of P-1 for synthesis of glycolipid biosurfactant. 1H and 13C nuclear magnetic resonance, Fourier transform infrared spectrum and mass spectrum analyses indicated that the extracted biosurfactant was affiliated with rhamnolipid. The results of this study indicate that the P-1 and/or biosurfactant produced by this strain have the potential to be used in bioremediation of hydrocarbon-contaminated soils.

The pharmacological activities and acute toxicity of the psilocin (PC) and dried residues of the crude extracts of psychotropic mushrooms were investigated in mice. The hallucinogenic substances were effectively isolated, by using methanol, from the species of Psilocybe semilanceata and Pholiotina cyanopus, that were collected in the north-east region of Poland. The chemical analysis of these extracts, which was performed by liquid chromatography with mass spectrometry detection (LC-MS), indicated the presence of psilocin and other hallucinogenic substances, including indolealkylamines and their phosphorylated analogues. When the pure psilocin or fungal extracts were used, slight differences in determined LD50 values were observed. However, the application of PC evoked the highest level of toxicity (293.07 mg/kg) compared to the activity of extracts from Ph. cyanopus and P. semilanceata, where the level of LD50 was 316.87 mg/kg and 324.37 mg/kg, respectively. Furthermore, the behavioral test, which considered the head-twitching response (HTR), was used to assess the effects of the studied psychotropic factors on the serotonergic system. Both, the fungal extracts and psilocin evoked characteristic serotoninergic effects depending on the dose administered to mice, acting as an agonist/partial agonist on the serotonergic system. A dose of 200 mg/kg 5-hydroxytryptophan (5-HTP) induced spontaneous head-twitching in mice (100% effect), as a result of the formation of 5-hydroxytryptamine (5-HT) in the brain. Compared to the activity of 5-HTP, the intraperitoneal administration of 1mg/kg of psilocin or hallucinogenic extracts of studied mushrooms (Ph. cyanopus and P. semilanceata) reduced the number of head-twitch responses of about 46% and 30%, respectively. In contrast, the administration of PC exhibited a reduction of about 60% in HTR numbers.

The differences in the chemical composition of the phenolic compounds of Salvia officinalis versus Salvia sclarea growing in different habitats, were studied. First, the optimal solvent - methanol - for ultrasonic extraction of phenolic compounds from these plants was chosen experimentally. Total phenolic content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. Total phenolic content was in the range of 63.9 to 134.4 mg GAE/g of plant depending on the studied species. The highest antiradical activity was displayed by the methanol fractions of S. sclarea varieties (83 and 67%). HPLC-DAD analysis of extracts was done in order to identify the presence of individual phenolic compounds. This was done by comparison of their retention times with those observed for 17 commercially available standard compounds. The results showed differences in the phenolics composition, with plants collected on Crimean peninsula accumulating more phenolic acids than Polish varieties. In turn, the Polish varieties of sage contain bigger amount of flavonoids in their tissues.

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To verify the hypothesis that cyanobacteria naturally biosynthesising polyphenolic compounds possess an active enzymatic system that enables them to transform these substances, such an ability of the biocatalytic systems of whole cells of these biota was assessed for the first time. One halophilic strain and seven freshwater strains of cyanobacteria representing four of the five taxonomic orders of Cyanophyta were examined to determine the following: (i) whether they contain polyphenols, including flavonoids; (ii) the resistance of their cultures when suppressed by the presence of exogenous hydroxychalcones—precursors of flavonoid biosynthesis and (iii) whether these photoautotrophs can transform hydroxylated chalcones. All examined strains were found to contain polyphenols and flavonoids, and the growth of their cultures was inhibited in the presence of 2′-hydroxychalcone, 2″-hydroxychalcone and 4″-hydroxychalcone. We also confirmed that the examined cyanobacteria transformed hydroxychalcones via hydrogenative bio-reduction and formed the corresponding hydroxydihydro derivatives with yields above 90% whenever the substrates were bioavailable for such a conversion. Moreover, we observed that the routes and efficiency of biohydrogenation (and hydroxylation) of chalcones were dependent on the location of the hydroxyl substituent. The final products obtained as the results of biotransformations were extracted from the media and identified by mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (1H NMR, 13C NMR, COSY, HSQC). Based on those results, we believe that the very efficient biohydrogenation of hydroxychalcones, which may easy be scaled up for biotechnological purposes, reflects the natural activity of the cyanobacterial defence system, because hydroxydihydrochalcones were less active inhibitors of the growth of cyanobacterial cultures than the corresponding substrates.

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