It has been shown that Allium species may help to prevent tumor promotion, cardiovascular diseases and aging; all processes that are associated with free radicals. Therefore the Allium species of both cultivated species (Allium nutans L., Allium fistulosum L., Allium vineale L., Allium psekemense B. Fedtsch, Allium cepa L., Allium sativum L.) and wild species (Allium flavum L., Allium sphaerocephalum L., Allium atroviolaceum Boiss, Allium schenoprasum L., Allium vineale L., Allium ursinum L., Allium scorodoprasum L.) from various locations were investigated for their antioxidative properties. The leaves were examined for activities of antioxidative enzymes (catalase, peroxidase, superoxide-dismutase, glutathione-peroxidase), non-enzymic antioxidants (reduced glutathione and total flavonoids), content of soluble proteins, vitamin C, carotenoids, chlorophylls a and b, as well as the quantities of malonyldialdehyde and *OH and O2*- radicals. Using a contemporary spectroscopic fluorescent method, lipofuscin, 'plant age pigments' were determined. ESR spectroscopy was used to follow the decrease of oxygen radicals in the presence of extracts of Allium species in phosphate buffer (pH 7). The results showed that all Allium species had strong antioxidative properties due to their high concentration of total flavonoids, high content of carotenoids and chlorophylls, and very low concentrations of toxic oxygen radicals. ESR signals of DMPO-OH radical adducts, in the presence of Allium extracts in phosphate buffer (pH 7), were reduced by up to 94.3%.

The goal of this work was to investigate a possible way of crosslinking polymer chains and the potential formation of intramolecular hydrogen bonds in thermosensitive poly(N-isopropylacrylamide-co-2-hydroxypropyl methacrylate) (p(NIPAM-HPMet)) hydrogels obtained by radical polymerization. The chemical structure of the synthesized hydrogels was investigated by Fourier transform infrared (FTIR) spectroscopy and XRD. The FTIR spectrum confirmed the presence of hydrogen bonds formed between the chains in the copolymer. XRD analysis confirmed the amorphous − crystalline structure of the copolymer. A three-glass transition and two melting temperatures were detected by DSC. It was found that the addition of HPMet increased the glass transition and melting temperatures of the p(NIPAM-HPMet) copolymer. The swelling transport mechanism of p(NIPAM-HPMet) changed from non-Fickian at 20 • C to case III or zero-order time-independent kinetics characterized by a linear mass uptake with time with increasing temperature at 40 • C.

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The influence of water molecule coordination onto the water-aromatic interaction. Strong interactions of water coordinating to a metal ion3

The molecular inclusion complex of atenolol with 2-hydroxypropyl-β-cyclodextrin was synthesized using the coprecipitation method. The complex obtained was characterized by FT-IR, 1 H-NMR, 13 C-NMR spectroscopy, as well as by DSC and X-ray diffraction analysis. The DSC analysis confirmed the existence of the complex with the endothermic atenolol melting peak at about 155 ºC disappearing. The X-ray diffraction patterns of the complex and 2-hydroxypropyl-β-cyclodextrin were very similar, thus confirming the complete inclusion of the atenolol molecule within the cavity of the 2-hydroxypropyl-β-cyclodextrin. The peaks originating from atenolol were completely absent in the diffractogram of the complex. 1 H-NMR and 13 C-NMR spectra showed certain changes in the chemical shifts of protons and C atoms from atenolol and 2-hydroxypropyl-β-cyclodextrin, indicating that a complex had been formed and also which protons participated in the hydrogen bonds which formed the complex. The atenolol solubility in water was improved (254 mg complex cm -3 , i.e., 37.5 mg atenolol cm -3 ), and in pH 3 HCl solution (251 mg complex cm -3 , i.e., 37 mg atenolol cm -3 ) when compared to pure atenolol, and even when compared to the atenolol complex with β-cyclodextrin. The increased solubility ensures greater bioavailability of the active component and, due to the low solubility, significantly corrects for the lack of the basic active substance and, simultaneously, increases its overall therapeutic effect, combined with reduced side effects.