DISCLOSING SUGAR POLYMERIZATION DETERMINANTS OF THE LEVANSUCRASE PROTEIN OF Pseudomonas syringae pv. TOMATO USING STRUCTURE-FUNCTION ANALYSISIS Invited lecture IDENTIFICATION OF HYDROCOLLOIDS IN CONFECTIONERY JELLY THE INFLUENCE OF DISSOLVING CONDITIONS OF POLYSACCHARIDES ISOLATED FROM CEREALS ON THEIR MOLECULAR CHARACTERISTICS
Levansucrases are bacterial exoenzymes that produce from sucrose fructan polymers of different chain length. The functions of levansucrases for the host bacteria are not clear yet. A plant pathogen Pseudomonas syringae pv. tomato has three levansucrase genes: lsc1, lsc2 and lsc3. We will characterize respective proteins and address structure function relationships of the Lsc3 protein focusing on polymerization determinants. Infrared spectroscopy offers many important advantages in the analysis
... es in the analysis of confectionary products. On the basis of infrared spectra in MIR or NIR region, the formulation of confectionary jelly can be easily proved and thus confirming the presence of gelatine or polysaccharides. The evaluation of the first or second derivatization of spectra by multivariable statistics allowed the separation of samples into groups according to their composition. Bee and honeycomb pollen is source of biologically active and nutritive compounds and thus has been used for the preparation of food supplements. Hydrophobic (fats, fatty acids, carotenes etc.) and hydrophilic (carbohydrates, polyphenols) fractions were isolated from pollen materials of various origin by subsequent extractions with hexane and ethanol. GC analysis confirmed that fatty acid distribution in pollen depends on botanical origin, processing and storage. Insoluble biopolymers (proteins, polysaccha-rides) were resistant to pepsin treatment in acidic conditions , but some decrease of the contribution of polysaccha-rides was detected due to their extraction to the medium. Bee pollen granules demonstrated evident variability in morphology and colour depending on the botanical origin. Differently coloured granules or pollen grains on their surface may be explained by some heterogeneity in botanical composition. Microscopy demonstrated significant differences in morphology of pollen grains of different botanical origin, and thus confirmed to be rapid and effective screening method for pollen identification. Dissolving of the polysaccharides such as starch, beta-glucan, water soluble and water insoluble arabinoxylans prior to molecular properties determination is crucial to obtain valuable information. Therefore the aim of the study was to check the influence of dissolving conditions of chosen polysaccharides on their molecular characteristics determined by HPSEC/RI.