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In this study we analysed mineral composition of bee pollen of different plant origin collected across Serbia using inductively coupled plasma -optical emission spectrometry. The most abundant elements were potassium, calcium, and magnesium. The samples were also exceptionally rich in iron and zinc, which are very important as nutrients. Judging by our findings, mineral composition of bee pollen much more depends on the type of pollen-producing plant than on its geographical origin. KEY WORDS: honey bee; geographical origin; macroelements; microelements; palynology; plant origin, nutritive value; toxicityIn addition to sugars, proteins, and lipids, bee pollen contains a variety of minerals. Mineral composition of pollen varies with the source location, source plant (1), and handling (2). If pollen has monofloral origin, some consistency in chemical composition can be expected. Otherwise, the composition of pollen can be considered as an average of plants that exist in a particular area (3). According to Campos et al. (4) and Serra-Bonvehí and Jordá (5), the content of major nutritional components can be averaged to 50 % of total carbohydrates, 2-16 % of polysaccharides and dietary fibres, 6-28 % of proteins, 4-8 % of lipids, and 6 % of free amino acids.Mineral content in pollen is usually expressed as ash content (6) or as the content of macro-and microelements (7-13). Only a few countries in the world (Brasil,

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Total phenolic content (TPC), total anthocyanin content (TAC), free and total ellagic acid content, sugars, minerals, and radical-scavenging activity were determined in nine berries harvested in Serbia. More than 30 phenolic compounds were identified; among them, 11 polyphenols and cis,trans-abscisic acid were quantified using UHPLC coupled with an LTQ-Orbitrap XL mass analyzer. For the first time chrysin, naringenin, pinocembrin, and galangin were quantified in some of the investigated berry species. The extraction efficiency of the two extraction systems, methanol and acetone, was investigated. It was found that acetone is a better extracting solvent for TPC, whereas more TAC was extracted by methanol. TPC in acetone extracts ranged from 177.51 to 459.71 mg gallic acid equiv/100 g frozen weight. TAC ranged from 5.39 to 96.94 mg cyanidin-3-glucoside/100 g frozen weight in methanol extracts. The amounts of both free and total ellagic acid were found to be higher in the acetone extract in comparison to the methanol extract.

Self-assembled semiconducting, paramagnetic polyaniline nanotubes have been synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in aqueous medium in the presence of colloidal silica particles of an average diameter approximately 12 nm, without added acid. The electrical conductivity of polyaniline nanotubes/silica nanocomposites is in the range (3.3-4.0)x10(-3) S cm(-1). The presence of paramagnetic polaronic emeraldine salt form of polyaniline and phenazine units in nanocomposites was proved by FTIR, Raman, and EPR spectroscopies. The influence of the initial silica/aniline weight ratio on the morphology of polyaniline/silica nanocomposites was studied by scanning and transmission electron microscopies. Nanocomposites synthesized by using the initial weight ratio silica/aniline

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