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Abstract: The antioxidant properties of alcoholic extracts from the leaves, berries and flowers of Sambucus nigra L. are estimated by means of DPPH and β-carotene/linoleic acid methods, and considered in relation to the extraction temperature (in the range 20–200°C) and to the level of flavonoids most representative for this plant. The extracts of S. nigra act as antioxidants neutralizing the activities of free radicals and inhibiting the co-oxidation reactions of linoleic acid and β-carotene. There is no direct correlation between the level of flavonoids in the extracts and their antioxidant activity. The data presented show that the extraction temperature strongly influences the antioxidant properties of the extracts, especially in the case of leaves. [Copyright &y& Elsevier]

The paper presents the results of calorimetric measurements and surface excess adsorption isotherms for n-butanol adsorption from n-hexane on a series of controlled porosity glasses characterized by different mean pore diameters. It is demonstrated that, in the region of very low alcohol concentration in solution, the heat of adsorption exhibits sharp maximum, independently of the pore diameter of adsorbent. This rather puzzling result is explained by the heterogeneity of the surface and the effects of molecular association of alcohol molecules in the solution. A simple theoretical model that supports our predictions is presented. [Copyright &y& Elsevier]