Grapes and wine are important sources of antioxidants in human diet. Phenolic substances contained in grapevine berries belong to an important group of natural substances that get into wine in the process of wine making. Polyphenols and flavonoids are primarily accountable for the colour and taste of the wine, they affect the perception of bitterness and acerbity. They also have antioxidant properties, thus have a positive effect on human health. Health benefits of polyphenolic substances from wine may be associated with a wide range of biological processes. Thanks to the development of modern analytical methods, wine is constantly being researched in terms of the content of antioxidants, and its importance to human health. Sixteen Slovak white wines of Muscat type produced in different geographical regions were analysed in this study. The object of this work was to determine total polyphenol content and total flavonoid content, and to evaluate antioxidant effects of quality wines of Muscat varieties produced in Slovakia. Antioxidant activity, total polyphenol content, and total flavonoid content of particular wines is described in the study. Studied characteristics were analysed by UV-VIS spectrometry method. Muscat wines showed weak to high antioxidant activity, ranging from 25.2% inhibition of DPPH to 67.7% inhibition of DPPH. Average antioxidant activity was 38.7% inhibition of DPPH. Total polyphenol content in the Muscat type varietal wines varied from 262.1 GAE.L-1 to 568.3 GAE.L-1. Average total polyphenol content was 382.13 GAE.L-1. The content of total flavonoids in Muscat type varietal wines ranged from 24.8 mg CE.L-1 to 169.1 mg CE.L-1. Average total flavonoid content was 100.5 mg CE.L-1.
Maltooligosaccharides (MOS) are homooligosaccharides that consist of 3–10 glucose molecules linked by α-1,4 glycosidic bonds. As they have physiological functions, they are commonly used as ingredients in nutritional products and functional foods. Many researchers have investigated the potential applications of MOS and their derivatives in the pharmaceutical industry. In this review, we summarized the properties and methods of fabricating MOS and their derivatives, including sulfated and non-sulfated alkylMOS. For preparing MOS, different enzymatic strategies have been proposed by various researchers, using α-amylases, maltooligosaccharide-forming amylases, or glycosyltransferases as effective biocatalysts. Many researchers have focused on using immobilized biocatalysts and downstream processes for MOS production. This review also provides an overview of the current challenges and future trends of MOS production.
β-N-acetylhexosaminidases have great potential in applied biocatalysis owing to their ability to act on a wide range of natural and modified substrates. In this work, β-N-acetylhexosaminidases from four Penicillium crustosum strains (PcHex) were studied. The production strains showed the highest enzymatic activity in the culture medium after 11–14 days of cultivation. The specific activity of the isolated and purified PcHex of hydrolysis of 4-nitrophenyl-N-acetyl-β-D-galactopyranoside was 15–20 U/mg protein. All isolated β-N-acetylhexosaminidases showed similar pH–activity profiles, with the optimum pH being 4.0–5.0 and the optimum temperature being 40 °C–50 °C. Apart from standard substrates, two synthetic substrates (5-bromo-4-chloro-3-indolyl-N-acetyl-β-D-galactoside and 2-chloro-4-nitrophenyl-β-D-galactopyranoside) were tested and successfully hydrolyzed using β-N-acetylhexosaminidase preparations. Maximum activity toward the fluorogenic substrate 4-methylumbelliferyl-N-acetyl-β-D-galactopyranoside (4MU-β-GalNAc) was observed for enzyme preparations from PcHex1 (15.38 U/mg protein) isolated from swab samples of books in the Slovak National Museum in Martin (Slovak Republic) and stored in our laboratory. The same enzyme preparation was used for the selective hydrolysis of β-anomer of 4MU-GalNAc from an anomeric mixture of 4MU-α/β-GalNAc. Thus, pure α-anomer (with the total yield being 90%) was separated from the mixture, which suggests the application potential of these enzymes.
V článku podávame pohľad na situáciu v súčasnom globalizovanom svete, v ktorom veľká časť obyvateľstva žije v prebytkových ekonomikách. Podmienky na život a životná úroveň sa výrazne zýšili v porovnaní s minulosťou a to dokonca aj v chudobných regiónoch. Otázkou zostáva, či materiálny dostatok prináša ľuďom aj primeraný pocit spokojnosti a šťastia. Uvádzame názory viacerých odborníkov na túto situáciu a závere podávame vlastné zhrnutie aký postoj zaujať k problematike šťastia v modernej globalizovanej spoločnosti.
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