Showing papers on "Polyphenol published in 1998"
TL;DR: The aim of this review is to summarize and analyze the vast and sometimes conflicting literature on tannins and to provide as accurately as possible the needed information for assessment of the overall effects of tannin effects on human health.
Abstract: Tannins (commonly referred to as tannic acid) are water-soluble polyphenols that are present in many plant foods. They have been reported to be responsible for decreases in feed intake, growth rate, feed efficiency, net metabolizable energy, and protein digestibility in experimental animals. Therefore, foods rich in tannins are considered to be of low nutritional value. However, recent findings indicate that the major effect of tannins was not due to their inhibition on food consumption or digestion but rather the decreased efficiency in converting the absorbed nutrients to new body substances. Incidences of certain cancers, such as esophageal cancer, have been reported to be related to consumption of tannins-rich foods such as betel nuts and herbal teas, suggesting that tannins might be carcinogenic. However, other reports indicated that the carcinogenic activity of tannins might be related to components associated with tannins rather than tannins themselves. Interestingly, many reports indicated negative association between tea consumption and incidences of cancers. Tea polyphenols and many tannin components were suggested to be anticarcinogenic. Many tannin molecules have also been shown to reduce the mutagenic activity of a number of mutagens. Many carcinogens and/or mutagens produce oxygen-free radicals for interaction with cellular macromolecules. The anticarcinogenic and antimutagenic potentials of tannins may be related to their antioxidative property, which is important in protecting cellular oxidative damage, including lipid peroxidation. The generation of superoxide radicals was reported to be inhibited by tannins and related compounds. The antimicrobial activities of tannins are well documented. The growth of many fungi, yeasts, bacteria, and viruses was inhibited by tannins. We have also found that tannic acid and propyl gallate, but not gallic acid, were inhibitory to foodborne bacteria, aquatic bacteria, and off-flavor-producing microorganisms. Their antimicrobial properties seemed to be associated with the hydrolysis of ester linkage between gallic acid and polyols hydrolyzed after ripening of many edible fruits. Tannins in these fruits thus serve as a natural defense mechanism against microbial infections. The antimicrobial property of tannic acid can also be used in food processing to increase the shelf-life of certain foods, such as catfish fillets. Tannins have also been reported to exert other physiological effects, such as to accelerate blood clotting, reduce blood pressure, decrease the serum lipid level, produce liver necrosis, and modulate immunoresponses. The dosage and kind of tannins are critical to these effects. The aim of this review is to summarize and analyze the vast and sometimes conflicting literature on tannins and to provide as accurately as possible the needed information for assessment of the overall effects of tannins on human health.
2,039 citations
TL;DR: The results suggest that tannins, which are found in many plant-based foods and beverages, are potentially very important biological antioxidants.
Abstract: Representative condensed and hydrolyzable tannins and related simple phenolics were evaluated as biological antioxidants using cyclic voltammetry, the metmyoglobin assay, and the deoxyribose assay. The redox potentials of the tannins were similar to those of structurally related simple phenolics. However, the tannins were 15-30 times more effective at quenching peroxyl radicals than simple phenolics or Trolox. One of the tannins, polygalloyl glucose, reacted an order of magnitude more quickly with hydroxyl radical than mannitol. These results suggest that tannins, which are found in many plant-based foods and beverages, are potentially very important biological antioxidants.
1,484 citations
TL;DR: The results demonstrate that the reactivities of the flavonoids in protecting low-density lipoprotein (LDL) against Cu2+ ion-induced oxidation are dependent on their structural properties in terms of the response of the particular flavonoid toCu2+ ions, whether chelation or oxidation, their partitioning abilities between the aqueous compartment and the lipophilic environment within the LDL particle, and their hydrogen-donating antioxidant properties.
Abstract: The flavonoids constitute a large group of polyphenolic phytochemicals with antioxidant properties in vitro. The interactions of four structurally related flavonoids (quercetin, kaempferol, rutin and luteolin) with Cu2+ ions were investigated in terms of the extent to which they undergo complex formation through chelation or modification through oxidation, as well as in their structural dependence. The ortho 3',4'-dihydroxy substitution in the B ring is shown to be important for Cu2+-chelate formation, thereby influencing the antioxidant activity. The presence of a 3-hydroxy group in the flavonoid structure enhances the oxidation of quercetin and kaempferol, whereas luteolin and rutin, each lacking the 3-hydroxy group, do not oxidize as readily in the presence of Cu2+ ions. The results also demonstrate that the reactivities of the flavonoids in protecting low-density lipoprotein (LDL) against Cu2+ ion-induced oxidation are dependent on their structural properties in terms of the response of the particular flavonoid to Cu2+ ions, whether chelation or oxidation, their partitioning abilities between the aqueous compartment and the lipophilic environment within the LDL particle, and their hydrogen-donating antioxidant properties.
875 citations
TL;DR: There is a need for increased understanding of the biodegradation of condensed tannins, particularly in ruminants, because tannase, a key enzyme in the degradation of hydrolysable tannine, is present in a diverse group of microorganisms, including rumen bacteria.
Abstract: Tannins are water-soluble polyphenolic compounds having wide prevalence in plants. Hydrolysable and condensed tannins are the two major classes of tannins. These compounds have a range of effects on various organisms--from toxic effects on animals to growth inhibition of microorganisms. Some microbes are, however, resistant to tannins, and have developed various mechanisms and pathways for tannin degradation in their natural milieu. The microbial degradation of condensed tannins is, however, less than hydrolysable tannins in both aerobic and anaerobic environments. A number of microbes have also been isolated from the gastrointestinal tract of animals, which have the ability to break tannin-protein complexes and degrade tannins, especially hydrolysable tannins. Tannase, a key enzyme in the degradation of hydrolysable tannins, is present in a diverse group of microorganisms, including rumen bacteria. This enzyme is being increasingly used in a number of processes. Presently, there is a need for increased understanding of the biodegradation of condensed tannins, particularly in ruminants.
489 citations
TL;DR: The results suggest that anthocyanins could be the key component in red wine in light of the protection against cardiovascular diseases, although this hypothesis needs in vivo evidence.
Abstract: Using liquid/liquid extraction, three fractions were obtained from an Italian red wine containing single polyphenolic subfractions: (1) phenolic acids and quercetin-3-glucuronide, (2) catechins and quercetin-3-glucoside, and (3) anthocyanins. Beside the scavenging capacity of the different fractions against hydroxyl and peroxyl radicals, the in vitro inhibition of low density lipoprotein oxidation and platelet aggregation (two main events in the pathogenesis of atherosclerosis) were tested. The antioxidant activity of the fractions has been compared with that of the original red wine before and after dealcoholization. The anthocyanin fraction was the most effective both in scavenging reactive oxygen species and in inhibiting lipoprotein oxidation and platelet aggregation. This higher activity can be explained by both its high concentration in red wine and its antioxidant efficiency, which, at least for peroxyl radical scavenging, was three times as high as that of the other two fractions. Our results suggest that anthocyanins could be the key component in red wine in light of the protection against cardiovascular diseases, although this hypothesis needs in vivo evidence.
469 citations
Book•
1 Jan 1998
TL;DR: In this article, the authors describe phenols and polyphenols as structure and biosynthesis, phenols as phenolic compounds, phenolic properties, and phenolic derivatives as ingredients in herbal medicines.
Abstract: 1. Polyphenols - structure and biosynthesis 2. Molecular recognition 3. Molecular recognition - phenols and polyphenols 4. Taste, bitterness and astringency 5. Maturation - changes in astringency 6. Anthocyanin co-pigmentation - fruit and floral pigments 7. Polyphenols and herbal medicines 8. Quinone tanning and oxidative polymerisation 9. Polyphenols, collagen and leather.
450 citations
TL;DR: It is considered that chocolate is stable against oxidative deterioration due to the presence of these polyphenolic compounds.
Abstract: The antioxidant components of cacao liquor, which is a major ingredient of chocolate, were isolated with column chromatography and high-performance liquid chromatography. Quercetin and its glucoside were identified by spectrometric methods. Clovamide and deoxyclovamide were characterized by 1H and 13C NMR and MS spectrometry. Their antioxidative activity was measured by peroxide value of linoleic acid and thiobarbituric acid reactive-substance value of erythrocyte ghost membranes and microsomes. In the bulk oil system, clovamide had the strongest antioxidative activity but was less active in the other experiments. In the case of the two hydrophilic systems, flavans such as quercetin and epicatechin were more potently effective than the glucosides. It is considered that chocolate is stable against oxidative deterioration due to the presence of these polyphenolic compounds. Keywords: Cacao liquor; polyphenols; antioxidant; catechin; clovamide
240 citations
TL;DR: In this article, the hydrogen-donating ability of catechins and extracts of green and black tea to Fremy's radical and galvinoxyl radical in aqueous and organic solutions, respectively, has been assessed.
Abstract: Electron spin resonance methodology has been used to assess the hydrogen-donating (antioxidant) ability of catechins and extracts of green and black tea to Fremy's radical and galvinoxyl radical in aqueous and organic solutions, respectively. Catechin flavanols accounted for 77-82% of the total antioxidant activity of green tea but only 47-58% of that of black tea. The radical quenching ability of the green tea was 21-24% more effective than that of the black tea in both aqueous and lipophilic systems. Epigallocatechin gallate was the most effective at reducing the two radical species, whereas epigallocatechin was least effective in the galvinoxyl/ethanol system, and catechin least effective in the Fremy's radical/water system. In a model system comprising a mixture of the flavanols in ethanolic or aqueous solution, in the same concentrations as they were present in the tea extracts, the antioxidant potential was a simple summation of the activity of the individual components indicating no synergistic or antagonistic side reactions. Results demonstrate that flavanol components of teas exhibit potent antioxidant activity in both aqueous and organic media. This will be of physiological relevance if such compounds partition into both the aqueous and lipid compartment of cells.
110 citations
TL;DR: In this paper, a synergistic antioxidation mechanism involving the recycling of α-tocopherol by the green tea polyphenol is proposed, which significantly increases the inhibition period and protects the latter from depletion.
Abstract: Peroxidation of linoleic acid was initiated by a water soluble azo initiator 2,2′-azo(2-amidinopropane)dihydrochloride (AAPH) in tert-butyl alcohol–water solution and inhibited by α-tocopherol and polyphenols extracted from green tea, i.e. (–)-epicatechin (EC), (–)-epigallocatechin (EGC), (–)-epicatechin gallate (ECG), (–)-epigallocatechin gallate (EGCG) and gallic acid (GA), either alone or in combination. The reaction kinetics were followed by oxygen uptake, formation of linoleic acid hydroperoxides and consumption of the antioxidants. It was found that the tea polyphenols could slow the rate of peroxidation with an activity sequence of EGCG > EGC ≈ ECG > EC ≈ GA, but no definite inhibition period was observed. On the other hand, the tea polyphenols could significantly increase the inhibition period of α-tocopherol and protect the latter from depletion with an activity sequence of EGCG ECG ≈ EGC > GA > EC when they were used in combination. A synergistic antioxidation mechanism involving the recycling of α-tocopherol by the tea polyphenol is proposed.
101 citations
TL;DR: It is believed that chocolate is stable against oxidative deterioration on account of the presence of these polyphenolic compounds, and it is also expected to have a protective role against lipid peroxidation in living systems.
Abstract: The antioxidative substances contained in cacao liquor, which is one of the major ingredients of chocolate, were separated by column chromatography and high-performance liquid chromatography. Three major compounds were purified and two of them were identified by 1H, 13C NMR and mass spectra as (-)-epicatechin (EC) and (+)-catechin (CA). Their antioxidative activity was measured by monitoring the peroxide value of linoleic acid and the thiobarbituric acid-reactive substance values of erythrocyte ghost membranes and microsomes. EC and CA had strong antioxidative effects in all three methods, but one unidentified peak was found to be less effective. Additionally, we ana-lyzed the polyphenol concentration of cacao liquor extractions produced in several countries. The total polyphenol concentration was 7.0 to 13.0%, catechin concentration was 0.31 to 0.49%, and epicatechin con-centration was 0.35 to 1.68% in the extractions. It is believed that cho-colate is stable against oxidative deterioration on account of the presence of these polyphenolic compounds, and it is also expected to have a pro-tective role against lipid peroxidation in living systems.
96 citations
TL;DR: Topical application of polyphenols simultaneously with phorbol-12-myristate-13-acetate (PMA) or mezerein resulted in significant protection against 7,12-dimethyl-benz[a]anthracene-induced skin tumors in mice.
Abstract: Ellagic acid (EA), tannic acid (TA), caffeic acid (CA), and ferulic acid (FA) offer considerable promise as anticarcinogens. The role of these dietary polyphenols was investigated in the promotional phase of carcinogenesis. Topical application of polyphenols simultaneously with phorbol-12-myristate-13-acetate (PMA) or mezerein resulted in significant protection against 7,12-dimethyl-benz[a]anthracene-induced skin tumors in mice. Caffeic acid was the most effective inhibitor of tumor promotion. In vivo and in vitro treatment of murine peritoneal macrophages with the tumor promoters resulted in stimulation of superoxide anion radical formation. Tannic acid, caffeic acid, and ferulic acid were stronger inhibitors of PMA- and mezerein-induced superoxide anion radical than ellagic acid in in vivo and in vitro conditions. Treatment of [1(3)-14C]glycerol- or [methyl-14C]choline chloride-labeled resident or thioglycollate-elicited macrophages with PMA and mezerein led to accumulation of radioactive diacylglycerol equivalents. The polyphenols were capable of inhibiting these releases.
TL;DR: In this article, an atmospheric pressure chemical ionization interface in the negative-ion mode, using collision-induced dissociation (CID) of precursor ions in parallel with UV-diode-array detection (DAD), was applied to the characterization in crude extracts of the water-soluble antioxidant phenolics from Mate leaves.
Abstract: Liquid chromatography/ion trap mass spectrometry with an atmospheric pressure chemical ionization (APCI) interface in the negative-ion mode, using collision-induced dissociation (CID) of precursor ions in parallel with UV-diode-array detection (DAD), was applied to the characterization in crude extracts of the water-soluble antioxidant phenolics from Mate leaves (Ilex paraguayensis). APCI gives unequivocal information about both the molecular mass of these compounds and some indications about their structure, which were confirmed by the UV-DAD fingerprints and by the diagnostic CID patterns. This allowed the identification of 10 constituents, including the 3 naturally occurring isomers of caffeoylquinic acid (CGA), namely neo-chlorogenic acid, chlorogenic acid and crypto-chlorogenic acid, as well as 3 isomeric dicaffeoyl quinic acids, rutin (quercetin-3-rutinoside), a diglycosyl derivative of luteolin, and 2 isomeric caffeoyl-glucosides. The aqueous extract of Mate, quantitatively analyzed for polyphenol and CGA content (HPLC), was tested for antioxidant activity in both a cell-free system (quenching of the stable free radical DPPH, 2,2-diphenyl-1-picryl-hydrazyl) and in a model membrane system (phosphatidylcholine liposomes). The results demonstrate that the extract is a strong radical scavenger, considerably more potent than the prototype chlorogenic acid, and this indicates a cooperative antioxidant interaction among its polyphenol components. © 1998 John Wiley & Sons, Ltd.
TL;DR: In this paper, model system experiments were carried out to determine if the binding of haze-active polyphenols to polyvinyl polypyrrolidone (PVPP) was similar to that of HA polyphenol to proteins.
Abstract: Model system experiments were carried out to determine if the binding of haze-active (HA) polyphenols to polyvinylpolypyrrolidone (PVPP) resembles the binding of HA polyphenols to HA proteins. Gall...
TL;DR: Activity-guided investigation of Artemisia indica Willd has led to isolation of exiguaflavone A, exigiain, and 2-(2, 4-dihydroxyphenyl)-5,6-methylenedioxybenzofuran, which exhibit in vitro antimalarial activities.
Abstract: Activity-guided investigation of Artemisia indica Willd has led to isolation of exiguaflavone A, exiguaflavone B, maackiain, and 2-(2,4-dihydroxyphenyl)-5,6-methylenedioxybenzofuran Exiguaflavones A and B exhibit in vitro antimalarial activities of 460 × 10-6 and 705 × 10-6 g/mL, respectively, against Plasmodium falciparum
TL;DR: A novel competitive tannin−salivary protein binding assay is described that allows the detailed investigation of binding of tannins to salivary proteins.
Abstract: Proline-rich proteins (PRP) are secreted by herbivores, including humans, in their parotid saliva into the oral cavity. These PRP have a high affinity for dietary complex phenols and tannins (CPT). The stable complexes formed may then pass through the digestive tract and are excreted. It is postulated that such complexes may modulate both the antinutritional effects and beneficial properties of CPTs. A novel competitive tannin−salivary protein binding assay is described that allows the detailed investigation of binding of tannins to salivary proteins. The assay is based on the competition between an enzyme-labeled tannin [(−)-epigallocatechin conjugated to horseradish peroxidase via a linker molecule] and a test tannin to bind to parotid salivary protein immobilized in the wells of a polystyrene microtiter plate. The binding affinities of a series of flavan-3-ol monomers from tea and a commercial tannic acid preparation were determined. Major differences in the binding affinities of the compounds tested t...
TL;DR: Banana pulp polyphenol oxidase was partially purified in a latent form using sequential aqueous two-phase systems based on Triton X-114 and PEG 8000/phosphate, avoiding the postpurification tanning of the enzyme and rendering only one enzymatic form in contrast to the many previously shown for this enzyme in both electrophoretic and isoelectrofocusing methods.
Abstract: Banana pulp polyphenol oxidase was partially purified in a latent form using sequential aqueous two-phase systems based on Triton X-114 and PEG 8000/phosphate. The purification achieved from a crude extract of banana pulp was 5-fold, with 50% recovery of the activity. The (poly)phenols, including tannins, were also reduced to 6% of the original, avoiding the postpurification tanning of the enzyme and rendering only one enzymatic form in contrast to the many previously shown for this enzyme in both electrophoretic and isoelectrofocusing methods. The enzyme was kinetically characterized with its natural substrate (dopamine) and tert-butylcatechol in the presence and in the absence of the main activating agent, sodium dodecyl sulfate. In addition, the effect of several inhibitors was also tested, and the Ksi values of the two most effective substrate analogues (tropolone and kojic acid) were determined. Keywords: Aqueous two-phase system; polyphenol oxidase; banana; Triton X-114; polyethylene glycol; latent ...
TL;DR: In this article, three new polyphenolic compounds, theaflavate B, isotheaflavin-3'-O-gallate and neothea-lavate-3-O-Gallate, have been characterised in extracts from black tea (the fermented leaves of Camellia sinensis) using 1D and 2D NMR spectroscopy.
TL;DR: In this paper, two types of commercial green tea from Japan and two active components of green tea, catechin and epicatechin, were assessed for their relative abilities to inhibit the oxidation of low-density lipoprotein mediated by human aortic endothelial cells (HAEC).
Abstract: Plant phenolics present in fruits and vegetables and that are particularly rich in tea and wine have received considerable attention because of their potential antioxidant activity. Two types of commercial green tea from Japan and two active components of green tea, catechin and epicatechin, were assessed for their relative abilities to inhibit the oxidation of low-density lipoprotein (LDL) mediated by human aortic endothelial cells (HAEC). The tea extracts, catechin and epicatechin, were incubated with HAEC and LDL for 12 h. After incubation, conjugated dienes were measured by spectrophotometry at 234 nm as an index of hydroperoxide formation, and hexanal was measured by static headspace gas chromatography as an index of hydroperoxide decomposition. On the basis of conjugated dienes and hexanal, inhibition of LDL oxidation was dose dependent for all compounds tested. LDL oxidation was inhibited 3.9−98% at concentrations ranging from 0.08 to 5 ppm of the green tea extracts. Both catechin and epicatechin i...
Patent•
9 Oct 1998
TL;DR: In this paper, a process for the production of polyphenol oligomers with polyphenolic hydroxyl groups is described. But the process is restricted to polyphenols having 2-17 monomeric units, n being an integer from 2-18.
Abstract: A process is disclosed for the production of polyphenol oligomers having n polyphenol monomeric units, n being an integer from 2-18. The process includes coupling of a protected polyphenol, having protected phenolic hydroxyl groups, with a C-4 functionalized polyphenol monomer. The protected polyphenol may be a protected polyphenol monomer or a protected polyphenol oligomer having 2-17 monomeric units. Advantageously, polyphenol monomeric units forming the polyphenol oligomers may be the same or different flavanoid compounds.
TL;DR: In this article, a range of chlorogenic acid concentrations were tested for inhibition of reverse transcription (RT) and PCR steps, and the RT step was inhibited at 6.0 to 7.5 microg, while the PCR step were inhibited at much lower concentrations of 1.2 to 1.8 microg.
TL;DR: In this paper, two biphenyl linked biflavanoids commonly associated with polyphenol oxidase-coupled products were isolated from Chardonnay grape pomace.
Journal Article•
TL;DR: The antifungal activity of polyphenolic complex (PC) of Acacia nilotica bark on Fusarium oxysporum was tested at 50, 25% and 10% dilution by measuring the mycelial growth.
Abstract: The antifungal activity of polyphenolic complex (PC) of Acacia nilotica bark on Fusarium oxysporum was tested at 50%, 25% and 10% dilution by measuring the mycelial growth. The extract of 50% concentration showed maximum growth inhibition (56%) as compared to control. The phytochemical analysis of bark extract showed presence of phenols, flavones, tannins and glycosides in the PC. Total phenols and tannin content in the dried bark sample were found to 9.86 g and 13.40 g and total flavonols and total o-dihydric phenols including chiorogenic acid were only 0.0025 g and 0.013 g per 100 g. The antifungal activity of the bark has been attributed to the presence of polyphenolic substances.
TL;DR: In this paper, a simple, sensitive and indirect spectrophotometric method for the determination of protein precipitable polyphenols (tannins) has been developed, based on the ability of the polyphenol to precipitate the synthetic, brown coloured azo-protein, bovine serum albumin-benzidine conjugate (BSA-Benzidine, mole ratio 1:7), which shows an absorption maxima at 405nm.
Patent•
9 Oct 1998
TL;DR: In this paper, a process for the production of polyphenol oligomers with polyphenolic hydroxyl groups is described. But the process is restricted to polyphenols having 2-17 monomeric units, n being an integer from 2-18.
Abstract: A process is disclosed for the production of polyphenol oligomers having n polyphenol monomeric units, n being an integer from 2-18. The process includes coupling of a protected polyphenol, having protected phenolic hydroxyl groups, with a C-4 functionalized polyphenol monomer. The protected polyphenol may be a protected polyphenol monomer or a protected polyphenol oligomer having 2-17 monomeric units. Advantageously, polyphenol monomeric units forming the polyphenol oligomers may be the same or different flavanoid compounds.
Patent•
4 Nov 1998
TL;DR: In this paper, fatty acid with 9-24 carbon atoms is acylated by adding acylating agent at 30-120 deg.c; and tea polyphenol solution in organic solvent is mixed with the above said acylation product at 40-80 deg c and through filtration, reduced pressure distillation of the filtrate to remove organic solvent and side product and to obtain oil-soluble teapolyphenol.
Abstract: Fatty acid with 9-24 carbon atoms is acylated by adding acylating agent at 30-120 deg.c; and tea polyphenol solution in organic solvent is mixed with the above said acylation product at 40-80 deg.c and through filtration, reduced pressure distillation of the filtrate to remove organic solvent and side product and to obtain oil-soluble tea polyphenol. The said product can be dissolved in oil completely at any proportion and is stable and has obvious anti-oxidation and fresh-keeping effect.
Patent•
30 Jun 1998
TL;DR: In this article, a polyphenol included in a raw material containing plural polyphenols is allowed to be adsorbed on an adsorption resin consisting of a styrene-based resin.
Abstract: PROBLEM TO BE SOLVED: To produce a polyphenol having a high purity, and useful as a raw material for producing a medicine or the like by allowing the polyphenol included in a raw material containing plural polyphenols to be adsorbed on a specific resin, and separating and purifying the desirable polyphenol by using a prescribed eluent. SOLUTION: A polyphenol included in a raw material containing plural polyphenols and preferably derived from a plant of Rosaceae is allowed to be adsorbed on an adsorption resin consisting of a styrene-based resin, and the adsorbed polyphenols are separated by using eluents such as water, an alkali and alcohols into desirable polyphenol groups (preferably the one consisting essentially of phenolcarboxylic acids or esters thereof, the one consisting essentially of esters of the polyphenol with an organic acid, or the like), and each of the groups is purified to provide the objective compound. Preferably, the polyphenol-containing solution of the raw material is diluted with a deionized water so as to form 10-1% total polyphenol concentration, and is regulated so as to have pH 5-6 and 22±2°C liquid temperature, when carrying out the adsorption. COPYRIGHT: (C)2000,JPO
Patent•
22 Dec 1998
TL;DR: In this article, the problem of obtaining a polyphenol-like food containing a compound having two or more hydroxyl group on the same benzene ring is solved by formulating an alkali metal salt (e.g., potassium chloride and sodium chloride) with the liquid.
Abstract: PROBLEM TO BE SOLVED: To obtain the subject homogeneous clear food hardly causing precipitation even by the addition of gelatin to the liquid containing a polyphenol by formulating an alkali metal salt with the liquid. SOLUTION: The objective get-like food containing a polyphenol is obtained by formulating an alkali metal salt (e.g. an alkali metal salt of an organic acid such as L-ascorbic acid, citric acid, tartaric acid, malic acid, fumaric acid and lactic acid, or a chlorine compound such as potassium chloride and sodium chloride) of preferably 0.01-5 wt.% based on the whole weight. The polyphenol is a generic name of a compound having two or more hydroxyl group on the same benzene ring, and exemplified by tannin, catechin, quercetin, caffeic acid and chlorogenic acid. A liquid containing the polyphenol includes a drink such as coffee, black tea, green tea, etc., containing the polyphenol, an extract thereof, a liquid product of the extract, a solution obtained by adding a pulverized extract thereof and a solution obtained by separately adding a polyphenol.
Patent•
5 Oct 1998
TL;DR: In this article, a subject composition for removing or alleviating a sense of incompatibility of the throat, especially extremely reducing the pain symptom of the throats by making the composition include a polyphenol and a bactericidal disinfectant as active ingredients.
Abstract: PROBLEM TO BE SOLVED: To obtain the subject composition for removing or alleviating a sense of incompatibility of the throat, especially extremely reducing the pain symptom of the throat by making the composition include a polyphenol and a bactericidal disinfectant as active ingredients. SOLUTION: This composition comprises (A) a polyphenol, preferably one or more kinds selected from (i) a hydrolysis type tannin and (ii) a condensation type tannin and (B) a bactericidal disinfectant, preferably one or more kinds selected from chlorhexidine, decalinium, cetyl pyridinium and their salts. Preferably the component (i) is one or more kinds of tannic acid, gallic acid, a gallic acid derivative, galloyl gallate, luteic acid, ellagic acid, etc., and the component (ii) is one or more kinds selected from catechin, epicatechin, leuco anthocyanin, leucocyanidin, etc. The amount of the component B is about 0.000025-0.2 pt.wt. based on 1 pt.wt. of the component A.
Patent•
2 Mar 1998
TL;DR: In this paper, a discoloration preventive agent is used to prevent the oxidation of polyphenols in fruits/vegetables to effect their discoloring prevention, while retaining the quality such as the flavor of the fruits and vegetables.
Abstract: PROBLEM TO BE SOLVED: To inexpensively obtain the subject discoloration preventive agent exhibiting excellent discoloration preventive effect, while retaining the quality such as flavor of the fruits/vegetables. SOLUTION: This discoloration preventive agent acts as follows: the activity of polyphenol oxidase, an oxidizing enzyme for polyphenols, is depressed by the action of betaine, thereby preventing the oxidation of the polyphenols in fruits/vegetables to effect their discoloration prevention; combinational use of betaine with other substance(s) having polyphenol oxidase activity inhibitory action affords further excellent polyphenol oxidase activity inhibitory effect; furthermore, adjustment of the pH level of fruits/vegetables to < 7, esp. <=4 using ascorbic acid or kojic acid or the like enables the polyphenol oxidase activity to be inhibited more perfectly.