Air pollution in the places of Betula pendula growth and development changes the physicochemical properties and the main allergen content of its pollen.

Pollen allergy becomes an increasing problem for humans, especially in the regions, where the air pollution level increases due to the traffic and urbanization. These factors may also affect the physiological activity of plants, causing changes in pollen allergenicity. The aim of the study was to estimate the influence of air pollutants on the chemical composition of birch pollen and the secondary structures of the Bet v1 protein. The research was conducted in seven locations in Malopolska region, South of Poland of a different pollution level. We have found slight fluctuations in the values of parameters describing the photosynthetic light reactions, similar spectra of leaf reflectance and the negligible differences in the discrimination values of the δ13C carbon isotope were found. The obtained results show a minor effect of a degree of pollution on the physiological condition B. pendula specimen. On the other hand, mean Bet v1 concentration measured in pollen samples collected in Kraków was significantly higher than in less polluted places (p = .03886), while FT-Raman spectra showed the most distinct variations in the wavenumbers characteristic of proteins. Pollen collected at sites of the increased NOx and PM concentration, show the highest percentage values of potential aggregated forms and antiparallel ß-sheets in the expense of α-helix, presenting a substantial impact on chemical compounds of pollen, Bet v1 concentration and on formation of the secondary structure of proteins, what can influence their functions.

The mechanism of thermal activated radical formation in potato starch studied by electron paramagnetic resonance and Raman spectroscopies.

Degradation of starch and the constituent fractions: amylopectin and amylose during thermal treatment in the range 423-503 K was investigated by electron paramagnetic resonance (EPR) and Raman spectroscopy. Degradation process was accompanied by the generation of carbon-centered stable radicals. EPR provided data on the nature and structure of radicals and on their evolution upon thermal treatment, whereas Raman spectroscopy allowed monitoring the changes of bonds in polysaccharides. It was found that amylose was the most susceptible toward high temperatures and the process of radical generation started at lower temperature than in amylopectin and starch, which were more resistant to thermal degradation.

Thermal effects on the structure of cereal starches. EPR and Raman spectroscopy studies.

The mechanism of thermal radical generation has been studied in cereal starches containing different amylose contents. Samples of four corn starches and one of wheat has been investigated using electron paramagnetic resonance and Raman spectroscopies. It has been found, that the content of amylose influences the character of thermally created radical species, but in opposite to potato starch, does not affect their amount. During storage of thermally treated starches the evolution of the EPR spectra has been observed. Raman spectra reveal the smaller changes in cereal starches structure occurring upon high temperature than those found for potato starch.