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The aim of this study was to determine the antimicrobial activity of essential oils obtained from sweet basil (Ocimum basilicum L. cv. ‘Genovese’) cultivated in the open field under different shading conditions (red, blue, and pearl nets with a shade index of 50 % and full sunlight exposure (control plants)), harvested at different times. The antimicrobial activity of basil essential oils (BEOs) obtained from all samples was determined for four microorganisms, while determinations for an additional five microorganisms included samples from non-shaded plants, plants grown under red and pearl nets, and second harvest of plants grown under blue net. Basil essential oil exhibited antimicrobial activity surpassing the activity of relevant commercial antibiotics regardless of growing conditions in the case of B. cereus, K. pneumoniae and C. albicans, while superior antimicrobial activity was exhibited in the case of essential oils from plants grown under blue nets in the case of S. aureus, E. coli and P. vulgaris. The influence of the application of colored shading nets was highly significant (p &lt, 0.01) in the cases of all analyzed microorganisms except C. albicans and P. aeruginosa, while the influence of harvest time was proven in the cases of all microorganisms except K. pneumoniae. ANOVA proved that antimicrobial activities are highly dependent on the methods of plant production, shading treatment, and harvest time. Obtained results are discussed in relation to previously determined composition and yield of essential oils from basil grown under shade nets and harvested in different periods.

The temperature- and pH-responsive poly(N-isopropylacrylamide-co-acrylic acid), p(NIPAM-co-AA), copolymer was synthesized by free radical polymerization and examined as a carrier for modified release of biochanin A. Biochanin A is a biologically active methoxylated isoflavone which exhibits estrogenic and other pharmacological activities. Due to its poor aqueous solubility and extensive first-pass metabolism, biochanin A has low bioavailability. The aim of this work was to incorporate biochanin A into the synthesized p(NIPAM-co-AA) copolymer and to examine its release at the body temperature and pH values that correspond to pH values of vaginal and rectal cavities. The amount of released biochanin A was monitored by the ultra-visible spectroscopy (UV-Vis) method. The structure of synthesized p(NIPAM-co-AA) copolymer and copolymer with incorporated biochanin A were characterized by using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) methods. The content of residual monomers in the synthesized copolymer was analyzed by using the high-pressure liquid chromatography (HPLC) method. The swelling behavior of p(NIPAM-co-AA) copolymer was monitored in relation to the temperature and pH values of the surrounding medium. For modelling the process of p(NIPAM-co-AA) copolymer swelling, the full three-level factorial design was applied.

The antioxidant activity of water, ethanol and methanol Hieracium pilosella L. extracts is reported. The antioxidative activity was tested by spectrophotometrically measuring their ability to scavenge a stable DPPH(•) free radical and a reactive hydroxyl radical trapped by DMPO during the Fenton reaction, using the ESR spectroscopy. Total phenolic content and total flavonoid content were evaluated according to the Folin-Ciocalteu procedure, and a colorimetric method, respectively. A HPLC method was used for identification of some phenolic compounds (chlorogenic acid, apigenin-7-O-glucoside and umbelliferone). The antioxidant activity of the investigated extracts slightly differs depending on the solvent used. The concentration of 0.30 mg/mL of water, ethanol and methanol extract is less effective in scavenging hydroxyl radicals (56.35, 58.73 and 54.35%, respectively) in comparison with the DPPH(•) radical scavenging activity (around 95% for all extracts). The high contents of total phenolic compounds (239.59-244.16 mg GAE/g of dry extract) and total flavonoids (79.13-82.18 mg RE/g of dry extract) indicated that these compounds contribute to the antioxidative activity.