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New approach of alginate encapsulation of polyphenolic rich extract from three wild edible forest fruits Cornelian cherry, chokeberry and blackberry was introduced. The aim of the current study was to design new dairy desserts with antioxidant properties by encapsulation and direct incorporation of berries juices The microencapsulation of berries extracts significantly retains (p < 0.05) higher amount of polyphenols and antioxidants in dairy desserts not only at the first day, but also after twenty days storage period. The highest antioxidant activity (523 mM TE/100 g (DPPH method) and 510 mM TE/100 g (FRAP method)) demonstrated dairy dessert with encapsulated blackberry juice followed by chokeberry and Cornelian cherry alginate encapsulated juices. The sensory evaluation of obtained dairy desserts with encapsulated berries juices showed satisfactory and overall higher scores for proposed new desserts compared to the direct incorporated fruits juices. Alginatebased encapsulation of polyphenolic extracts from Cornelian cherry, chokeberry and blackberry were evaluated as proper technique for preservation of natural antioxidants in dairy desserts. [ABSTRACT FROM AUTHOR]

Water-soluble and acid-soluble pectic polysaccharides with significant immunostimulating activity were isolated from alcohol-insoluble solids (AIS) of leek. Pectic polysaccharides characterized with high anhydrouronic acid content and common pectic sugars - L-arabinose, D-galactose, D-glucose, and L-rhamnose. It was accomplished that D-galactose content was the highest, which allowed the assumption that pectin sugar side chains were from galactan type. Enzyme modification of acid-extracted pectin was realized. Different pectin-degrading enzymes were used. The first modified pectic fraction, obtained after endopolygalacturonase action and alcohol precipitation contained rhamnogalacturonan I and had high D-galactose content. The second fraction obtained from the first, after ß-galactosidase treatment characterized with low D-galactose content. Probably this was result from ß-galactosidase hydrolysis of pectin side chains. It was proved by the action of ß-galactosidase that galactan side chains were mainly composed of ß-(1?4)-linked D-galactose. It was accomplished that rhamnogalacturonan I had higher immunostimulating activity than the initial pectic polysaccharide, which confirmed the statement that pectin hairy regions were responsible for the biological activity. The second fraction had lower D-galactose content and lower activity than the first. Probably galactan side chains were responsible for the immunostimulating activity. [ABSTRACT FROM AUTHOR]

Orange and lemon peels were used for obtaining pectic polysaccharides. Citrus peels were previously treated with 96% ethanol, and the obtained alcohol-insoluble solids (AIS) were subjected to a sequential extraction with hot distilled water and hot 0.5% HCl. Water- and acid-extracted orange (WEOP and AEOP) and lemon (WELP and AELP) pectins were obtained. Acid extraction gave higher yields of pectin than water extraction and lemon peels were richer in pectin. Comparative investigations were carried out with chromatographically purified commercial citrus pectin (CPCP). Chemical and physicochemical characterization of all pectins was accomplished. It was found that pectins were similar in anhydrouronic acid content (AU?C, 69-81%), but differed in their degree of methylesterification (DM, 55-81%). Generally water-extracted pectins were with higher DM. Both orange pectins were with higher DM and degree of acetylation (DA, 2%), in comparison with the corresponding lemon pectins. Water-extracted pectins were with higher degree of feruloylation (DF, 0.12-0.34%). To our knowledge this is the first report on the estimation of ester-linked ferulic acid in orange and lemon peel pectins. Pectic polysaccharides differed in molecular weight and homogeneity. WELP was with the highest molecular weight and homogeneity. The pectins contained D-galacturonic and D-glucuronic acids, L-arabinose, D-galactose, L-fucose, L-rhamnose and D-xylose. All investigated pectins showed immunostimulating activity by complement activation in the classical pathway at 1.25 and 2.5 mg/mL. Pectic polysaccharides were modified with endopolygalacturonase. Enzyme-modified CPCP and WEOP had higher anti-complementary activity than the corresponding initial pectins. [ABSTRACT FROM AUTHOR]

The current study aimed to investigate exopolysaccharides (EPSs) produced by two Antarctic yeasts isolated from soil and penguin feathers samples collected on Livingston Island (Antarctica). The strains were identified as belonging to the species Leucosporidium yakuticum (LY) and Cystobasidium ongulense (CO) based on molecular genetic analysis. The EPS production was investigated using submerged cultivation. Different chemical, chromatographic, and spectral analyses were employed to characterize EPSs. LY accumulated 5.5 g/L biomass and 4.0 g/L EPS after 120 h of cultivation, while CO synthesized 2.1 g/L EPS at the end of cultivation, and the biomass amount reached 5.5 g/L. LY-EPS was characterized by a higher total carbohydrate content (80%) and a lower protein content (18%) by comparison with CO-EPS (62%, 30%). The LY-EPS mainly consisted of mannose (90 mol%), whereas CO-EPS had also glucose, galactose, and small amounts of uronic acids (8-5 mol%). Spectral analyses (FT-IR and 1D, 2D NMR) revealed that LY-EPS comprised a typical β-(1 → 4)-mannan. Branched (hetero)mannan, together with β/α-glucans constituted the majority of CO-EPS. Unlike LY-EPS, which had a high percentage of high molecular weight populations, CO-EPS displayed a large quantity of lower molecular weight fractions and a higher degree of heterogeneity. LY-EPS (100 ng/mL) elevated significantly interferon gamma (IFN-γ) production in splenic murine macrophages and natural killer (NK) cells. The results indicated that newly identified EPSs might affect IFN-γ signaling and in turn, might enhance anti-infectious responses. The data obtained also revealed the potential of EPSs and yeasts for practical application in biochemical engineering and biotechnology., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)