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  1. 7 Polish Journal of Food and Nutrition Sciences

  2. 5 Bromatologia i Chemia Toksykologiczna

  3. 4 Journal of Physiology and Pharmacology

  4. 3 Żywność Nauka Technologia Jakość. Suplement

  5. 2 Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

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  1. 4 Druzynska B.

  2. 2 Bettuzzi S.

  3. 2 Dmowski P.

  4. 2 Duda-Chodak A.

  5. 2 Mitek M.

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  1. 1 2020

  2. 1 2017

  3. 1 2013

  4. 1 2012

  5. 4 2011

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1

Determination of catechin forms in black tea using isocratic elution HLPC system

100%
Smiechowska M., Dmowski P.
Herba Polonica
|
2004
|
tom 50
|
nr 3-4
In this paper the content of catechins in black fermented tea, imported to Poland by sea from China, India, Indonesia, Kenya, Malawi and Vietnam, was determined. The material was collected directly from ship cargo holds. An isocratic elution system was applied for the separation of catechins in tea. Extracts were prepared from tea samples and analysed for catechin content by HPLC. Catechin identification from chromatograms of examined tea extracts was performed by comparison of retention times with respective standards purchased from Sigma Aldrich. Chromatographic analysis by HPLC shows that examined tea contained (-)-(EGCG) in highest quantities, ranging from 148.9-292.3 mg/l, as proved by comparative analysis with a chromatogram of catechin standards, based on their retention times. Only Chinese tea contained more (-)-(EGC) - 266.2, and (-)-(EC) - 193.6, than (-)-(EGCG) - 148.9 mg/l.
2

The radical scavenging capacity of green tea

86%
Muzolf M., Gliszczynska-Swiglo A., Tyrakowska B.
Polish Journal of Natural Sciences. Supplement
|
2007
|
tom 04
63-69
3

HPLC analysis of catechins from Camelia spp.

86%
Sempruch C., Stefaniuk A., Chrzanowski G., Leszczynski B.
Polish Journal of Food and Nutrition Sciences
|
2011
|
tom 61
|
nr Suppl.1
4

Clinical relevance of the inhibitory effect of green tea catechins [GTCs] on prostate cancer progression in combination with molecular profiling of catechin-resistant tumors: an integrated view

86%
Bettuzzi S., Rizzi F., Belloni L.
Polish Journal of Veterinary Sciences
|
2007
|
tom 10
|
nr 1
Prostate cancer (CaP) is a fast-growing health and social problem already representing the second leading cause of cancer-related death among men in Western countries. Lifestyle-related factors and diet are major contributors for CaP promotion. Because of unfavourable prognosis of extra-prostatic CaP, prevention is considered the best approach to fight it at present time. Green Tea Catechins (GTCs) were proven effective at inhibiting cancer growth in several laboratory studies. We recently performed a pilot clinical trial in HG-PIN subjects showing that only 1/30 tumour was diagnosed in subjects treated for 1 year with 600 mg/die GTCs, while 9/30 cancers were found in placebo-treated men. CaP is an elusive disease, whose biological behaviour is difficult to predict. We have recently described and validated a RT-qPCR method based on a 8-genes signature that significantly discriminated benign tissue from CaP in both humans and TRAMP mice spontaneously developing CaP. In the animal model, also GTCs-resistant CaP was significantly discriminated from GTCs-sensitive CaP, i.e. responding to GTCs administration. Preliminary experiments in our laboratory have shown that this method can be successfully applied to a single tissue needle biopsy specimen in humans. The combination of these results may be of particular significance on the field. In fact, GTCs treatment for men at high risk of CaP as first line prevention therapy in combination with the 8-genes signature profiling in tissue needle biopsies for real time monitoring of patient's response might importantly change, in the near future, the clinical managing of this highly diffuse malignancy.
5
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Comparison of methods for determining the content and polymerization of proanthocyanidins and catechins

86%
Oszmianski J., Bourzeix M.
Polish Journal of Food and Nutrition Sciences
|
1996
|
tom 05
|
nr 2
The methods with vanillin (V), Folin-Ciocalteau (FC) or dimethyla- minocinnamaldehyde (DC) reagent and spectometric method at 280 nm (A) for determining the content of proanthocyanidins and catechins and their polymerization degree were compared. The (+) catechin, (-)epicatechin and their dimer and trimer standards, and grape wine, wine concentrate and powdered wine were examined. The DC reagent appeared most sensitive in the catechin and proanthocyanidin analysis with the molar absorption values for catechins being 55-fold higher than for the FC reagent In the proanthocyanidin analysis with the DC reagent the use of catechin standard curve is not recommended for the determination of proanthocyanidin content because the concentrations of 0.5 g/L for dimers and 0.3 g/L for trimers were obtained instead of 1 g/L in model solutions. Hie V/DC value approximated most closely the real values of proanthocyanidin polymerization.
6
Content available remote

Molecular targets of [-]-epigallocatechin-3-gallate [EGCG]: specificity and interaction with membrane lipid rafts

72%
Patra S. K., Rizzi F., Silva A., Rugina D. O., Bettuzzi S.
Journal of Physiology and Pharmacology. Supplement
|
2008
|
tom 59
|
nr 9
217-235
7
Content available remote

Green tea extracts lower serum folates in rats at very high dietary concentrations only and do not affect plasma folates in a human pilot study

72%
Augustin A., Frank J., Augustin S., Langguth P., Ohrvik V., Witthoft C. M., Rimbach G., Wolffram S.
Journal of Physiology and Pharmacology
|
2009
|
tom 60
|
nr 3
103-108
Green tea catechins (GTC) have been shown to inhibit the activities of enzymes involved in folate uptake. Hence, regular green tea drinkers may be at risk of impaired folate status. The present experiments aimed at studying the impact of dietary GTC on folate concentrations and metabolism. In a human pilot study (parallel design) healthy men consumed for 3 weeks 6 capsules (~670 mg GTC) per day (2 capsules with each principal meal) containing aqueous extracts of the leaves of Camellia sinensis (n=17) or placebo (n=16). No differences in plasma folate concentrations were observed between treatments. We further fed groups of 10 male rats diets fortified with 0, 0.05, 0.5, 1, or 5 g GTC/kg for 6 weeks. Only at the highest intake, GTC significantly decreased serum 5-methyl-tetrahydrofolate concentrations in rats, while mRNA concentrations of reduced folate carrier, proton-coupled folate transporter/heme carrier protein 1, and dihydrofolate reductase (DHFR) remained unchanged in intestinal mucosa. Using an in vitro enzyme activity assay, we observed a time- and dose-dependent inhibition of DHFR activity by epigallocatechin gallate and a green tea extract. Our data suggest that regular green tea consumption is unlikely to impair folate status in healthy males, despite the DHFR inhibitory activity of GTC.
8

Anti-nutritive and anti-allergic properties of green tea extract depend on catechins concentration and processing

72%
Velickovic T. C., Tantoush Z., Kravic B., Mihajlovic L., Apostolovic D., Atanaskovic-Markovic M., Stanic-Vucinic D.
Polish Journal of Food and Nutrition Sciences
|
2011
|
tom 61
|
nr Suppl.1
9

High pressure-modified starches as carriers for phenolic compounds

72%
Gorecki A. R., Blaszczak W., Hernandez T., Estrella I., Bartolome B., Garrido L.
Polish Journal of Food and Nutrition Sciences
|
2011
|
tom 61
|
nr Suppl.1
10
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Rapid high performance thin layer chromatographic method for quantitation of catechin from extracts of cashew leaves - a short report

72%
Jaiswal Y., Tatke P., Gabhe S., Vaidya A.
Polish Journal of Food and Nutrition Sciences
|
2013
|
tom 63
|
nr 1
Cashew is a tropical tree with immense commercial value and the use of its various parts in the confectionary, food, herbal and tanning industry has gained tremendous importance. Thus, the development of quality control method for routine analysis of various products of this widely used plant would be a great help to analysts. The phytochemistry of this plant has not been explored in detail. Anacardium occidentale Linn. (cashew) is reported to contain many antioxidant and polyphenolic compounds. However, there have been no reports published for the HPTLC analysis of the extracts of cashew leaves. Hence, an attempt has been made to develop a HPTLC method for estimation of catechin from leaf extracts. The present paper reveals a rapid high performance thin layer chromatographic method developed for quantitation of catechin from extracts of cashew leaves. The chromatographic parameters such as solvent system, development time, saturation time, detection wavelength were optimized. The mobile phase toluene: ethyl acetate: methanol: formic acid (6:6:1:0.1v/v/v/v) gave the best resolution for various components. The separation of various components and quantitation of amount of catechin was successfully carried out from extracts of cashew leaves. The aqueous extract of leaves contained a higher amount of catechin as compared to ethanol extract. The presence of tannins and phenolics was visualised as bluish-black bands with 5% alcoholic FeCl3 as visualising agent. The method can prove to be a rapid, sensitive and economic alternative as compared to other chromatographic methods especially HPLC for detection of catechin in various food products and herbal formulations.
11
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Antioxidant properties of acetone extracts from selected fresh and dried spices

72%
Druzynska B., Wojda M.
Polish Journal of Food and Nutrition Sciences
|
2007
|
tom 57
|
nr 2[A]
47-51
The purpose of the study was to determine antioxidant properties of acetone extracts from selected fresh and dried spices. Three spices have been examined: garlic, oregano and rosemary. Preparations were obtained by the extraction of polyphenols with a 70% acetone solution. The contents of total polyphenols and total catechin were determined in the study. The ability of total polyphenols contained in the obtained extracts to chelate Fe(II) ions was examined, too. The antioxidant properties of the examined extracts were assayed with three methods: against stable, synthetic DPPH radicals, cation-radicals ABTS and against hydroxyl radicals. On the basis of findings it turned out that condensed tannins are a dominant group of polyphenols in oregano, rosemary and fresh garlic. Granular garlic contained a higher level of catechins than tannins. All preparations of fresh spices dispalyed the ability to chelate iron ions. All extracts had antioxidant properties against synthetic radicals, with the exception of garlic preparation which did not inhibit hydroxyl radicals. Extracts of fresh spices demonstrated better antioxidant properties.
12
Content available remote

The inhibitory effect of polyphenols on human gut microbiota

58%
Duda-Chodak A.
Journal of Physiology and Pharmacology
|
2012
|
tom 63
|
nr 5
13

The effect of water plant extracts addition on the oxidative stability of meat products

58%
Wojciak K., Dolatowski Z., Okon A.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2011
|
tom 10
|
nr 2
Background. Natural antioxidants extracted from plants have a lot of antioxidants catechins, epigallocatechins (green tea) rosmariquinone, rosmaridiphenol (rosemary), capsaicinoids (red pepper). They can be used as altematives to the synthetic antioxidants because of their equivalence or greater effect on inhibition of lipid oxidation and haem pigment (nitrosohemachrome) protection. The aim of the study was to compare the effect of addition of green tea extract, red pepper extract and rosemary extract while curing process on colour and lipid stability during refrigerated storage of meat products. Material and methods. The pork meat was ground (10 mm piate) and divided into four equal parts. To the first part (control sample - C) was added curring mixture in amount of 2.2% in a ratio of meat dissolved in water. To the rests of parts were added the same curring mixtures in the same proportion dissolved in 0.5% water plant extracts: green tea (GT), red pepper (P), rosemary (R) respectively. Ali samples were left at 4°C for 24 hours. After curing, samples were stuffed in casings and then heated in water until a final internal temperature of 70°C was reached. Ali samples were stored up to 30 days at 4°C. Analysis of acidity, oxidation - reduction potential, thiobarbituric acid reactive substances (TBARS), surface colour (Hunter L*, a* and b* values) were measured directly after production and after 10, 20 and 30 days of chilling storage. Results. The addition of the plant extracts (pepper, green tea, rosemary) to the pork meat samples does not change significantly acidity of the samples during chilling storage. Ali plants extracts effectively reduce lipid oxidation in cooked pork meat compared to the control. Pepper extract was effective in maintaining redness because of its reduction activity (low potential redox value in sample) and low TBARS values in sample during chilling storage. Conclusions. Addition of pepper extract and green tea extract in curing meat process helped with nitrosomyoglobin formation and curb prevention of metmyoglobin formation which stabilized the colour of product during chilling storage.
14

Antyoksydacyjne wlasciwosci zielonej herbaty

58%
Ostrowska J., Stankiewicz A., Skrzydlewska E.
Bromatologia i Chemia Toksykologiczna
|
2001
|
tom 34
|
nr 2
131-140
15
Content available remote

Gastroprotective and cicatrizing activity of the Ziziphus joazeiro Mart. leaf hydroalcoholic extract

58%
Brito S. M. O., Martins A. O. B. P. B., De Oliveira M. R. C., Vidal C. S., De Lacerda Neto L. J., Ramos A. G. B., Da Gruz L. P., Nascimento E. A., Da Costa J. G. M., Coutinho H. D. M., Quintans-Junior L. J., De Menezes I. R. A.
Journal of Physiology and Pharmacology
|
2020
|
tom 71
|
nr 3
16

Zawartosc wybranych zwiazkow bioaktywnych a walory sensoryczne herbaty

58%
Dmowski P., Smiechowska M.
Bromatologia i Chemia Toksykologiczna
|
2008
|
tom 41
|
nr 3
530-535
17
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Content available

Intracellular reduced glutathione content in normal and type 2 diabetic erythrocytes: effect of insulin and (-)epicatechin

58%
Rizvi S. I., Zaid M. A.
Journal of Physiology and Pharmacology
|
2001
|
tom 52
|
nr 3
18
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Content available

Enzymatic oxidation of polyphenols in fruit products and model solutions

58%
Los J., Wilska-Jeszka J., Pawlak M.
Polish Journal of Food and Nutrition Sciences
|
1996
|
tom 05
|
nr 1
Polyphenoloxidase (PPO) activity, total polyphenols and flavanols contents in various fruit species were investigated in relation to their susceptibility to browning processes. Marked differences in substrate affinities of PPO preparations from apples and pears were found. The rate of browning of (+)catechin solutions was higher for the apple PPO than for the pear enzyme. In contrast, the pear PPO catalysed an oxidation of (-)epicatechin to higher extent. Phenolic acids, i.e. chlorogenic and caffeic, were oxidised more slowly than catechins. It was observed that in pulps from fruits rich in polyphenoloxidase, e.g. from apples and pears, stored at room temperature, the browning process was accompanied by considerable losses of flavanols (40% after 1 h). In strawberry pulps exhibiting a low PPO activity no decrease of flavanols was observed under the same conditions.
19

Metabolism of phenolic compounds in Vitis riparia seeds during stratification and during germination under optimal and low temperature stress conditions

58%
Wrobel M., Karamac M., Amarowicz R., Fraczek E., Weidner S.
Acta Physiologiae Plantarum
|
2005
|
tom 27
|
nr 3A
We studied the alterations in phenolic compounds in grape seeds during their stratification and germination under optimal conditions (+25 °C) and at low temperature (+10 °C). Biological materials in the study were seeds of Vitis riparia. Phenolic compounds were extracted from defatted seeds using 80 % methanol or 80 % acetone. The content of total phenolics was determined with the Folin-Ciocalteau reagent, while the content of tannins was determined by vanillin assay and the protein (BSA) precipitation method. The RP - HPLC method was used to determine phenolic compounds (phenolic acids, catechins) in the extracts. High amounts of tannins, catechins, gallic acid and lesser amounts of p-coumaric acid were found in the seeds. The content of total phenolics in acetone extracts was higher than that obtained using methanol. The amounts of phenolic acids and tannins found in V. riparia seeds after stratification were much lower. It may confirm a possible role of these compounds in dormancy of V. riparia seeds. After 72 h of low temperature treatment, inhibition of grape root growth and biochemical changes in seeds were detected. The chilling stimulated increased accumulation of some phenolic compounds (free gallic acid and catechins) in the seeds. These substances can protect plants against some abiotic stressors.
20

Antyoksydacyjne wlasciwosci polifenoli okryw nasiennych fasoli kolorowej

51%
Mikolajczak A., Druzynska B.
Żywność Nauka Technologia Jakość. Suplement
|
1999
|
tom 06
|
nr 3
112-117
W pracy podjęto tematykę związaną z przebadaniem właściwości antyoksydacyjnych związków poli-fenolowych, a głównie tanin, obecnych w okrywach nasion fasoli kolorowej. Izolację polifenoli przeprowadzano za pomocą ekstrakcji łuski 0,5% roztworem kwasu solnego w metanolu. Zebrany ekstrakt zagęszczano pod próżnią, a następnie liofilizowano. W preparatach oznaczano m. in. zawartość tanin hydrolizujących i skondensowanych, katechin oraz antocyjanów. Preparaty wykazywały właściwości przeciwutleniające. Preparat z fasoli brązowej, zawierający większą ilość tanin (92%), okazał się bardziej efektywnym antyoksydantem niż preparat z fasoli czerwonej.
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