Tokaj essence is produced by fermentation of concentrated must from botrytised grape berries. The highest content of polyphenols was determined in the essence of 1999 (275.8 ±18.17 mg.L -1 ) and the lowest in the sample of 2015 (118.8 ±12.28 mg.L -1 ). Antioxidant activity was determined by two methods DPPH and PRAC (permanganate reducing antioxidant capacity). Antioxidant DPPH method showed that the essence of year 1999 had significantly the highest activity (63.4 ±0.81 µmol.L -1 Trolox) while essence of year 2015 (47.5 ±1.58 µmol.L -1 Trolox) featured the lowest activity. The results of method PRAC, which determine the total reducing capacity of the essence, do not correlate with the results of DPPH and total phenolic content, because of higher content of saccharides, which gave false positive test results. The method PRAC is not suitable for measuring antioxidant activity of tokaj esence. The results showed that aging of wine increased the content of polyphenols and also its antioxidant activity. High content of polyphenols and the great antioxidant activity of Tokaj wine receive their beneficial effect to human health.

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The experimental work aimed to determine the effect of different applications of alginite on some antioxidant indexes in the extracts of the Mentha × piperita L. (cultivars Strawberry Mint and Chocolate Mint), and the acute toxicity of water extracts of the studied mint plants to freshwater invertebrates of the genus Daphnia sp. The content of total polyphenols, phenolic acids, and antioxidant activity were determined by spectrophotometric methods. The OECD manual No. 202 was used for the determination of EC 50 48 h in the water extracts of both variants of mint. The content of total polyphenols in all groups of the cv. Chocolate Mint ranged from 3.05 to 3.37 mg CAE/100 g DW. On the other hand, the significantly lower (p <0.001) content of total polyphenols (from 1.01 to 1.38 mg CAE/100 g DW) was found in all groups with the cv. Strawberry Mint. The antioxidant activity determined by the DPPH method was from 115.7 to 119.5 mg TAEC/100 g DW in the cv. Chocolate Mint, but was 2 times lower (from 48.8 to 65.7 mg TAEC/100 g DW) in the cv. Strawberry Mint. The content of phenolic acids in the cv. Chocolate Mint was significantly higher (but only 1.1-fold), than in the cv. Strawberry Mint. The mean acute toxicity after 48 h exposure of the cv. Chocolate Mint to daphnids was nearly 40 times higher than the mean acute toxicity of the cv. Strawberry Mint (EC 50 0.25 mg/L vs. EC 50 9.62 mg/L, respectively). We can conclude, that the cv. Chocolate Mint is a more potent source of substances with antioxidant properties, such as polyphenols and phenolic acids, which is reflected in the significantly increased DPPH radical scavenging activity as compared to the cv. Strawberry Mint. We can only speculate that the higher amounts of the aforementioned active substances in the cv. Chocolate Mint were associated with an increased level of acute toxicity to the tested water invertebrates as compared to the cv. Strawberry Mint. The impacts of alginite application on all studied antioxidant indexes as well on the acute toxicity of the extracts of both variants of mint were not confirmed.

Over the past years there has been a growing interest to vegetable raw materials evaluated from the viewpoint of their potential antimicrobial activity. Vaccinium genus plants are known to contain a whole spectrum of biologically active substances with anti-inflammatory, antidiabetic, gene-protective, antioxidant and antimicrobial properties. The purpose of the work was to study the antimicrobial, antioxidant and some biochemical properties of alcoholic extracts of fruit and leaves of Vaccinium vitis-idaea L., gathered in the Ukrainian Carpathians. Methods. The plants for the study were gathered around the village of Pylypets, Mizhhiria rayon, Zakarpatska oblast (Transcarpathia). From the fruit and leaves, ethyl and methyl extracts were produced. The subjects for study were their antioxidant activity (by DPPH method), total tannin and flavonoids (by spectrophotometric method), and antimicrobial activity (by diffusion-into-agar method). For the purpose of study, type and clinical isolates were used from the oral cavity of human patients suffering from inflammatory diseases of periodontium, characterized by wide resistance spectrum to antibiotics. Results. The reviewed extracts were observed to have a higher antimicrobial activity against Gram-positive bacteria. The highest antimicrobial activity was shown by the extract of Vaccinium vitis-idaea L. fruit. Its antimicrobial activity was registered upon both test and clinical isolates of S.aureus, including methicillin-resistant ones. The ethyl fruit extract and methanol leaf extract were established to show high antimicrobial effect upon S.pyogenes. The ethanol fruit and leaf extracts and methanol fruit extract were observed to show weak antimycotic activity. The extracts were characterized by high antioxidant activity, with the highest effect peculiar for ethyl leaf and fruit extracts, and somewhat lower one for methyl extracts. The ethanol fruit extract was characterized by the highest tannin level out of all extracts under review. Conclusions. The antimicrobial and high antioxidant activity of the ethanol extract of Vaccinium vitis-idaea L. fruit and leaves, and absence of the antimicrobial effect against the probiotic strain of Lactobacillus plantarum, characterized by the antagonistic activity against opportunistic microorganisms, cause the advisability of their complex application as the basis for phytobiotics.

Silver nanoparticles (Ag NPs) with antibacterial activity can be prepared in different ways. In our case, we used ecological green synthesis with Agrimonia eupatoria L. The plant extract was used with Ag NPs for the first time to prepare termosensitive in situ gels (ISGs). Such gels are used to heal human or animal skin and mucous membranes, as they can change from a liquid to solid state after application. Ag NPs were characterized with various techniques (FTIR, TEM, size distribution, zeta potential) and their antibacterial activity was tested against Staphylococcus aureus and Escherichia coli. In accordance with the TEM data, we prepared monodispersed spherical Ag NPs with an average size of about 20 nm. Organic active compounds from Agrimonia eupatoria L. were found on their surfaces using FTIR spectroscopy. Surprisingly, only the in situ gel with Ag NPs showed antibacterial activity against Escherichia coli, while Ag NPs alone did not. Ag NPs prepared via green synthesis using plants with medicinal properties and incorporated into ISGs have great potential for wound healing due to the antibacterial activity of Ag NPs and the dermatological activity of organic substances from plants.