polyphenols
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The short review is focused on apple polyphenols ? their classification, biological activities and methods of isolation. The polyphenols are classified according to their chemical structure. Specific isolation methods for selected compounds are given.
OBJECTIVES: This study aimed to determine trend in polyphenol consumption in the Czech Republic during the last three decades. Additionally, it provides a brief overview of the beneficial effects of polyphenols in several body systems. METHODS: Data from the Phenol-Explorer 3.6, a specialized database of polyphenolic substances, were assigned to the resources of the Czech Statistical Office on the consumption of food and beverages in the Czech Republic for the years 1989-2022. The average daily intake of polyphenols was determined by multiplying the average annual consumption of each type of food by the polyphenol content obtained from the database; results were given in milligrams of polyphenols per inhabitant and day. Since the food items in the data sources are not identical, it was necessary to create an extensive model of food categories. RESULTS: The current value of polyphenol intake is 1,673 mg per day per inhabitant; however, this level most likely reflects methodological underestimation. The favourable increase in dietary polyphenol intake in the Czech population - doubling, to be precise - which we observed from 1989 to 2007, has been replaced by the opposite trend in the last 15 years. The current intake of polyphenols corresponds to the level that was already achieved in 2004. Hydroxycinnamic acids (from the group of phenolic acids) are the most prevalent dietary polyphenols, followed by flavanols (from the group of flavonoids). The most frequent source of polyphenols in the Czech population are non-alcoholic beverages such as coffee, tea and juices, followed by fruits, cereals, and vegetables, respectively. CONCLUSION: Current trend of dietary polyphenol intake in the Czech population is slightly decreasing. This tendency, lasting since 2008, is indisputably negative. Plant polyphenols offer opportunities for inexpensive interventions in health promotion.
- MeSH
- dieta statistika a číselné údaje MeSH
- lidé MeSH
- polyfenoly * aplikace a dávkování analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- MeSH
- antioxidancia * MeSH
- biopotraviny * MeSH
- fyziologie výživy MeSH
- lidé MeSH
- ochranné látky MeSH
- polyfenoly * MeSH
- Check Tag
- lidé MeSH
Polyphenols form one of the largest groups of natural compounds and possess a wide range of biological properties. These activities can be influenced by the galloyl moiety within their structures. A multitude of galloylated polyphenolic compounds occurs in nature, but galloylated phenols are also produced synthetically to influence their biological properties. This review provides a comprehensive summary of current knowledge about natural (galloylated catechins, theaflavins and proanthocyanidins, penta-O-galloyl-β-d-glucose, gallotannins, ellagitannins, ellagic acid and flavonols) and semisynthetic gallates with a focus on their biological activity and toxicity issues. The effects of tea catechins (epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate) and semisynthetic galloyl esters of the flavonolignans silybin and 2,3-dehydrosilybin from the milk thistle (Silybum marianum) on angiogenesis were used as examples of the structure-activity relationship (SAR) study.
- MeSH
- katechin analogy a deriváty chemie farmakologie MeSH
- lidé MeSH
- polyfenoly chemie farmakologie MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
An overview mapping recent trends in the determination of polyphenols of natural origin (mostly flavonoids) and their synthetic derivatives by electromigration methods is presented. The overview (covering the period of the recent 5 years and comprising 61 references) is focused on capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) with various detection methods. Techniques comprising on-line pre-separation such as isotachophoresis (ITP)-CZE and flow-injection-CZE, chiral separations and CZE evaluation of antioxidation activity are also discussed.
- MeSH
- antioxidancia * analýza chemie MeSH
- chromatografie micelární elektrokinetická kapilární metody trendy MeSH
- elektroforéza kapilární metody trendy MeSH
- fenoly * analýza chemie MeSH
- flavonoidy * analýza chemie MeSH
- polyfenoly MeSH
- spektrofotometrie ultrafialová MeSH
- Publikační typ
- práce podpořená grantem MeSH
Long-range non-covalent interactions play a key role in the chemistry of natural polyphenols. We have previously proposed a description of supramolecular polyphenol complexes by the B3P86 density functional coupled with some corrections for dispersion. We couple here the B3P86 functional with the D3 correction for dispersion, assessing systematically the accuracy of the new B3P86-D3 model using for that the well-known S66, HB23, NCCE31, and S12L datasets for non-covalent interactions. Furthermore, the association energies of these complexes were carefully compared to those obtained by other dispersion-corrected functionals, such as B(3)LYP-D3, BP86-D3 or B3P86-NL. Finally, this set of models were also applied to a database composed of seven non-covalent polyphenol complexes of the most interest. Graphical abstract Weakly bound natural polyphenolsᅟ.
Compared to most other alcoholic beverages, the shelf life of beer is much more limited due to its instability in the bottle. That instability is most likely to appear as turbidity (haze), even sedimentation, during storage. The haze in beer is mostly caused by colloidal particles formed by interactions between proteins and polyphenols within the beer. Therefore, beers are usually stabilized by removing at least one of these components. We developed and constructed a Saccharomyces cerevisiae strain with a proline-rich QPF peptide attached to the cell wall, using the C-terminal anchoring domain of α-agglutinin. The QPF peptide served to bind polyphenols during fermentation and, thus, to decrease their concentration. Strains displaying QPF were able to bind about twice as much catechin and epicatechin as a control strain displaying only the anchoring domain. All these experiments were done with model solutions. Depending on the concentration of yeast, uptake of polyphenols was 1.7-2.5 times higher. Similarly, the uptake of proanthocyanidins was increased by about 20 %. Since the modification of yeasts with QPF did not affect their fermentation performance under laboratory conditions, the display of QPF appears to be an approach to increase the stability of beer.
