Synytsya A., Míčková K., Jablonský I., Sluková M., Čopíková J. (2008): Mushrooms of genus Pleurotus as a source of dietary fibres and glucans for food supplements. Czech J. Food Sci., 26: 441-446.Fruit bodies (separately pilei and stems) of mushrooms Pleurotus ostreatus (four strains) and Pleurotus eryngii were characterised as a source of polysaccharides. The contents of glucans and dietary fibres were determined with using the respective Megazyme enzymatic kits. Enzymatic analysis of the fruit bodies confirmed significant differences in the contents of these components among the species and strains. The stems contained more insoluble dietary fibres than the pilei in all the cases and more β-glucans in most cases. However, relatively high contents of β-glucan (20-50% of dry matter) could be a result of incomplete enzymatic hydrolysis of insoluble α-1,3-glucans. Nevertheless, low food quality stems of mushrooms Pleurotus sp. could be a valuable source of cell wall glucans for the preparation of food supplements.Keywords: mushrooms Pleurotus; glucans; dietary fibres; food supplements For millennia, humankind has been valued mushrooms as an important edible and medical resource (Chang 1980;Breene 1990;Wasser 2002). The dry matter of mushroom fruit bodies is about 5-15%, they have a very low fat content and contain 19-35% proteins. Mushroom fruit bodies are rich in vitamins, mainly B 1 , B 2 , C, and D 2 (Manzi et al. 1999;Mattila et al. 2000), and contain some important elements such as K and P (Vetter 2007). The content of carbohydrates, which are mainly present as polysaccharides or glycoproteins, ranges 50-90%; the most abundant polysaccharides are chitin, α-and β-glucans and other hemicelluloses (e.g. mannans, xylans and galactans). 442Vol. 26, No. 6: 441-446 Czech J. Food Sci. 1988). Their solubility in water strongly depends on the molecular structure and conformation. Glucans bound to proteins or to chitin are usually insoluble in water. Mushroom-derived substances with antitumour, immunomodulating, and antioxidative properties are currently used as dietary supplements. Mushroom polysaccharides with antitumour action differ greatly in their chemical compositions and configurations, as well as in their physical properties. Immunomodulatory and antitumour activities are exhibited by a wide range of glycans extending from homopolymers to highly complex heteropolymers; the differences in their activities can be correlated with the solubility in water,molecular size, branching rate and form (Augustín 1998; Ooi & Lui 1999;Wasser 2002;Novak & Vetvicka 2008). Besides the well-known antitumour β-(1→3),(1→6)-glucans (Kuniak et al. 1992(Kuniak et al. , 1998, a wide range of biologically active glucans of different structures have been described. Linear or branched polysaccharides chains occur with a backbone composed of α-or β-linked glucose units, and their various side chains can be attached in different ways. The main source of biologically active polysaccharides appears to be fungal cell walls consisti...

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The aim of the bioassay-guided fractionation was the selection of the most potent group of compounds responsible for the protection of sunflower bee pollen grains. Synthesis of prospective antifungal polyamides of hydroxycinnamic acids was based on previous structural elucidation of ethanol soluble fraction by 1H,1H-PFG-COSY, 1H,13C-HSQC, FT-IR, FT-Raman, and LC–MS experiments. The main compounds found were tri-p-coumaroylspermidines accompanied by other HCAA of spermidine and putrescine. Several model HCAA derivatives were prepared to test their antifungal activity against widespread spoilage fungi (A. niger 42 CCM 8189, F. culmorum DMF 0103, and P. verrucosum DMF 0023). A. niger CCM 8189 and F. culmorum DMF 0103 exhibited higher resistance to the antifungal effects of hydroxycinnamic acid amides, whereas P. verrucosum DMF 0023 was the most sensitive strain. It has been discovered the effect of HCAA polarity on the role of secondary metabolites in the microbial protection of pollen grains. The combination of bioassay-guided fractionation, structural elucidation, selection of prospective compounds, and their synthesis to determine their antifungal properties could be considered as an original approach.

Wholemeal flours from various cereals and pseudocereals are a valuable source of nutritionally important fiber components, especially beta-glucans and arabinoxylans, as well as bioactive substances accompanying dietary fiber. Most types of whole-wheat flours have unfavorable baking and sensory properties. The finest granulation of bran particles in the flour has a significant effect on reducing or eliminating these deficiencies. Special disintegration equipment is required to achieve fine granulation of the bran particles. In this study, we have tested a special type of impact mill (originally intended for grinding of plastics) to produce special finely ground wholemeal flours with lower starch damage and higher farinographic absorption. Moisture content in the studied flours was significantly lower (7.4–9.8%) than is common in standard flour (13–14%). According to the results of flour analyses obtained from several cereal sources, it seems that especially in rye and wheat, this technology is suitable for both achieving fine granulation of bran particles and in terms of not very substantial damage of starch granules.

Horáčková Š., Mühlhansová A., Sluková M., Schulzová V., Plocková M. (2015): Fermentation of soymilk by yoghurt and bifidobacteria strains. Czech J. Food Sci., 33: 313-319.Soy and milk based products fermented by yoghurt culture YC-381 alone or in combination with two probiotic cultures (Bifidobacterium animalis subsp. lactis BB 12 and Bifidobacterium bifidum CCDM 94) were prepared. Bacteria growth, the amounts of lactic acid, acetic acid, and acetaldehyde were compared after 16 h of fermentation at 37°C. The changes of isoflavones concentrations were also monitored in soy products. The growth of Streptococcus thermophilus and bifidobacteria was similar in both media, but Lactobacillus delbrueckii subsp. bulgaricus showed a better growth in milk. Titratable acidity and the concentrations of acids were consistently higher in cow milk than in soymilk at the end of fermentation. Bifidobacteria, compared to the yoghurt culture, were only able to acidify the media to the half values. Comparing the bifidobacteria strains, Bifidobacterium animalis subsp. lactis BB 12 exhibited a better ability to acidify milk. The strain Bifidobacterium bifidum CCDM 94 was able to release 6.90 mg/100 ml of isoflavone aglycones in soymilk.