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1

Study of caffeine concentrations in infusions of selected green tea with component of fruit

100%

Stachelska-Wierzchowska A.

Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze

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2014

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nr 3

2

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Actual solubility (S|real.|), level of hydrophilic-lipophilic balance (HLBRequ., HLBD, HLBG) and partition coefficient (log P) of phytochemicals contained in Ext. Camellia sinensis L. aqu. siccum in the light of general Hildebrand- Scatchard-Fedors theory of solubility

100%

Marczynski Z., Skibska B., Nowak S., Jambor J., Zgoda M. M.

Herba Polonica

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2018

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tom 64

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nr 2

Using the general Hildebrand-Scatchard-Fedors theory of solubility, the mole fraction (x2) of solubility of phytochemicals contained in the dry green tea leaves was calculated which determines the profile of pharmacological activity.The applicative purpose of the study was to estimate the actual solubility of phytochemicals – S|real.| [mol/dm3] in water and in water-ethanol solutions of diversified polarity (εM) for their selective extraction and optimal formulation of oral solid dosage form.The basic physico-chemical and structural quantities of phytochemicals and corresponding mathematical equations of general Hildebrand-Scatchard-Fedors theory of solubility were used to calculate the actual solubility – S|real.| and the level of hydrophilic-lipophilic balance (HLB).The calculated actual solubility values – S|real.| [mol/dm3] collated with correlation equations enabled the assessment of phytochemical capability for the process of mass exchange on phase boundary. Correlation equations for the dependence log P = f (– log S|real.|) point to the structural preferences of phytochemicals in the kinetics of the mass exchange (diffusion) through the natural phase boundary.Calculations and correlations between the values characterizing the actual solubility – S|real.|, media polarity (water, ethanol and their solutions) and the partition coefficient (log P) including the level of hydrophilic-lipophilic balance (HLB) show that basing on thermodynamic components of the general Hildebrand-Scatchard-Fedors theory of solubility, the diffusion profile of phytochemicals contained in the green tea extract (Ext. Camellia sinensis L. aqu. siccum) through the biological phase boundary as well as optimal choice of the extraction medium for selective extraction of the class of phytochemicals can be estimated.

3

The radical scavenging capacity of green tea

100%

Muzolf M., Gliszczynska-Swiglo A., Tyrakowska B.

Polish Journal of Natural Sciences. Supplement

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2007

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tom 04

63-69

4

The influence of time and type of solvent on efficiency of the extraction of polyphenols from green tea and antioxidant properties obtained extracts

100%

Druzynska B., Stepniewska A., Wolosiak R.

Acta Scientiarum Polonorum. Technologia Alimentaria

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2007

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tom 06

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nr 1

The aim of the study was to investigate the influence of the type of solvent and time on efficiency of the extraction of polyphenols and antioxidant properties extracts obtained from green tea. Extraction was conducted at room temperature using four solvents: water and 80% ethanol, 80% methanol and 80% acetone (water solutions, v/v) at 15, 30 and 60 minutes. Extracts were analysed for contents of polyphenols and catechins. The antioxidant properties have been determined by two methods: scavenging activity against DPPH and the method with ABTS+. The abilities of extracts to chelate iron ions (II) have been investigated too. On the basis of findings it turned out that both type of solvent and time have a significant influence on extraction of polyphenols from green tea. The best solvent for the extraction of total polyphenols was 80% acetone, whereas for catechins was water. The increase of extraction of polyphenols with prolonged extraction time was observed. All extracts had antioxidant properties against DPPH and ABTS+ and abilities to chelate iron ions (II)

5

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

100%

Bettuzzi S., Rizzi F., Belloni L.

Polish Journal of Veterinary Sciences

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2007

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tom 10

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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.

6

Induction of apoptosis in vitro using epigallocatechin-3-gallate [EGCG] in selected tumour cells

100%

Borska S., Gebarowska E., Wysocka T., Drag-Zalesinska M., Zabel M.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

7

The effect of green tea extract on the activity of alcohol dehydrogenase in the liver of rats

100%

Chrostek L., Tomaszewski W., Szmitkowski M.

Acta Toxicologica

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2005

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tom 13

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nr 1

8

Effect of Camellia sinensis extract on the expression level of transcription factors and cytochrome P450 genes coding phase I drug-metabolizing enzymes

84%

Bogacz A., Karasiewicz M., Bartkowiak-Wieczorek J., Ozarowski M., Seremak-Mrozikiewicz A., Kujawski R., Mikolajczak P. L., Mrozikiewicz-Rakowska B., Bobkiewicz-Kozlowska T., Czerny B., Grzeskowiak E., Mrozikiewicz P. M.

Herba Polonica

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2013

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tom 59

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nr 4

Green tea (Camellia sinensis) is widely used as a popular beverage and dietary supplement that can significantly reduce the risk of many diseases. Despite the widespread use of green tea, the data regarding the safety as well as herb-drug interactions are limited. Therefore, the aim of our study was to assess the influence of standardized green tea extract (GTE) containing 61% catechins and 0.1% caffeine on the expression level of rat CYP genes and the corresponding transcription factors expression by realtime PCR. The findings showed that GTE resulted in a significant decrease of CYP2C6 expression level by 68% (p<0.001). In case of CYP3A1 and CYP3A2, the mRNA levels were also reduced by extract but in a lesser degree compared to CYP2C6. Simultaneously the significant increase in the mRNA level of CAR, RXR and GR factors was observed by 54% (p<0.05), 79% (p<0.001) and 23% (p<0.05), respectively after 10 days of green tea extract administration. In addition, there was noted a small increase of CYP1A1 expression level by 21% (p>0.05) was noted. No statistically significant differences were observed for CYP1A2 and CYP2D1/2. In the same study we observed an increase in amount of ARNT gene transcript by 27% (p<0.05) in the long-term use. However, green tea extract showed the ability to stimulate HNF-1α both after 3 and 10 days of treatment by 30% (p<0.05) and 80% (p<0.001), respectively. In contrast, no change was observed in the concentration of HNF-4α cDNA. These results suggest that GTE may change the expression of CYP enzymes, especially CYP2C6 (homologue to human CYP2C9) and may participate in clinically significant interactions with drugs metabolized by these enzymes.

9

Green tea macerate as ingredient in cosmetic emulsions

84%

Moldrzyk J., Wieczorek D., Wybieralska K.

Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze

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2014

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nr 3

10

Rozdzial garbnikow katecholowych roznych gatunkow zielonych i czarnych herbat za pomoca chromatografii kolumnowej

84%

Stanczyk A., Wedzisz A.

Bromatologia i Chemia Toksykologiczna

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2009

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tom 42

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nr 4

1117-1120

11

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

84%

Velickovic T. C., Tantoush Z., Kravic B., Mihajlovic L., Apostolovic D., Atanaskovic-Markovic M., Stanic-Vucinic D.

Polish Journal of Food and Nutrition Sciences

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2011

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tom 61

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nr Suppl.1

12

Evaluation of soluble oxalates content in infusions of different kinds of tea and coffee available on the Polish market

84%

Rusinek E.

Roczniki Państwowego Zakładu Higieny

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2012

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tom 63

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nr 1

Background. Tea and coffee are the potentially rich source of oxalic acid, which can act as a antinutrient. Objective. The aim of this study was to determine and evaluate the content of soluble oxalates in teas and coffees available on the Polish market. Material and method. The green, red and black teas, and black natural ground and instant coffees were used for preparing the infusions. The manganometric method was used for the determination of the oxalates in the infusions. Results. The mean oxalates content in the infusions from 3 g of black teas was 115.68 mg/100cm3 and was higher as compared to red teas (101.91 mg/100cm3) and green teas (87.64 mg/100cm3). Disregarding the variety of analyzed teas, the largest oxalates content was in infusions of pure one-component tea - “Sir Roger” (164.82-174.22 mg/100cm3), while the lowest oxalates content was noted in the tea containing the components from other plants (“Bio-Active” with grapefruit juice – reaching as low level as 39.00 mg/100cm3). Instant coffees contained larger amount of oxalates than natural ground coffees. Irrespective of the kind of the tested coffees, the lowest oxalates content was found in the infusions from the following coffees: Tchibo Exclusive - 19.62 mg/100cm3, Gala ulubiona - 37.32 mg/100cm3, and Maxwell House - 38.40 mg/100cm3, while the highest oxalates content in instant coffee - Nescafe Espiro 51.80 mg/100cm3. Conclusions. The results revealed a significant relation between phytochemical composition of analyzed teas and coffees and the level of soluble oxalates in infusions prepared from the tested products.

13

Consumption of black and green teas as a dietary source of polyphenols in Polish inhabitants of the Mazovian region

84%

Drywien M., Podkowska J., Frackiewicz J., Gornicka M.

Roczniki Państwowego Zakładu Higieny

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2015

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tom 66

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nr 1

Background. Tea is a very popular drink throughout many parts of the world, that includes Poland. The tea infusion (cup of tea) itself contains phenolic compounds with anti-oxidant properties that constitute 30% of the dry mass of tea leaves responsible for a health promoting effect on the human body. Objectives. To estimate the determinants and amounts of black and green tea consumed by a selected population group, along with their polyphenols intake from tea. Material and Methods. A survey was conducted of 281 subjects in 2012 from the Mazovian region of Poland, recruited from social-networking sites which had been sent a web application questionnaire (Mini-ankiety.pl). Results. Subjects were aged 18-56 years, of whom the majority (73%) were aged 21-30 years. City dwellers constituted 86%, whilst those remaining were from small towns (14%). Black tea was drunk by 80% of whom 39% did so daily, whilst green tea was drunk by 72% of whom 17% did so daily. Determinants affecting the amounts of tea drinking were principally gender, education, place of residence and number of household members. Women significantly drank more than one cup of green tea daily compared to men. Those with a higher education significantly drank more than one cup of black tea daily compared to those with lower education levels. Homeowning subjects with 2 household members significantly drank more than one cup of green tea daily than the others. The average daily intakes of polyphenols from black tea in those who drank so regularly was 503 mg and that for green tea was 361 mg. Conclusions. The main source of tea polyphenols was found to be black tea as this was drunk more often than green tea. There is a need for promoting more green tea to be drunk as a source of polyphenols.

14

Morphological alterations in the jejunal mucosa of aged rats and the possible protective role of green tea

84%

Hassan Z. A., Zauszkiewicz-Pawlak A., Abdelrahman S. A., Algaidi S., Desouky M., Shalaby S. M.

Folia Histochemica et Cytobiologica

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2017

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tom 55

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nr 3

15

Comparison of polyphenolic composition of extracts from honeysuckle, chokeberries and green tea - a short report

84%

Frejnagel S.

Polish Journal of Food and Nutrition Sciences

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2007

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tom 57

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nr 1

The aim of the study was to compare the polyphenolic composition of extracts from different plant sources. Extracts from two new plants rich in polyphenols, i.e. chokeberries and honeysuckle, were compared with the well-investigated green tea polyphenols. All extracts obtained were characterised by a high content of polyphenols: green tea – 611 mg/g, honeysuckle – 633 mg/g and chokeberries – 714 mg/g. Honeysuckle and chokeberries extracts consisted mainly of anthocyanins (321.2 and 404.5 mg/g, respectively), whereas green tea extract contained mainly flavan-3-ols (587.9 mg/ g).

16

Purification process influence on green tea extracts' polyphenol content and antioxidant activity

84%

Gramza-Michalowska A., Korczak J., Hes M.

Acta Scientiarum Polonorum. Technologia Alimentaria

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2007

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tom 06

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nr 2

The research examined green tea ethanol extract, subjected to different purification processes with use of active carbon, bleaching earth, and mixture of acetone, acetic acid, water, with or without earlier hexane treatment. Purified extracts were examined according to total polyphenols content, antioxidant activity in linoleic acid emulsion and antiradical activity in DPPH• radical scavenging method. Highest polyphenol content was evaluated in the extract purified with bleaching earth, lowest however in purified with solvents mixture. Antioxidant activity of green tea extracts in linoleic acid emulsion indicated that highest antioxidative effectivity coefficient (Aec) values represented sample purified with active carbon and solvents mixture. Highest DPPH• radical scavenging activity was found in sample purified with solvents mixture, other samples however represented close activity. The present research indicated that plant extracts purification processes resulted in decrease of total polyphenols content, however without its antioxidant activity decrease

17

Green tea as an antioxidant which protects against alcohol induced injury in rats - a histopathological examination

84%

Baltaziak M., Skrzydlewska E., Sulik A., Famulski W., Koda M.

Folia Morphologica

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2004

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tom 63

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nr 1

Our study with animal models was designed to test the hypothesis that green tea protects against chronic (over 4 weeks) alcohol induced liver injury in rats. The research was conducted on Wistar male rats divided into 4 research groups: I — received the Libera-De Carli control diet (L-DC), II — received (L-DC) and green tea, III — received (L-DC) and ethanol and IV — received (L-DC), green tea and ethanol. When comparing groups I and II we saw less intensive steatosis in group II than in group I, which can suggest that green tea may affect the accumulation of fat in the hepatocytes and protect them against steatosis and disruption. In III, the ethanol group, the steatosis of the liver increased considerably and the green tea which was given with ethanol in group IV did not halt this, as in group IV we also observed intensive steatosis in the liver. From this data we conclude that green tea has an important, although not fully understood role in preventing liver injury.

18

Zielona herbata a nowotwory

84%

Gornicka M.

Żywność, Żywienie a Zdrowie

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1999

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tom 08

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nr 4

398-399

19

Extracts from selected tannin-rich foods - a relation between tannins content and sensory astringency

67%

Troszynska A., Narolewska O., Wolejszo A.

Polish Journal of Food and Nutrition Sciences

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2007

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tom 57

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nr 3

329-333

Extracts of polyphenols were obtained from black chokeberry, green tea, and walnut using acetone-water and ethanol-water system (8:2, v/v). The extracts were subjected to sensory evaluation using the method of sensory scaling and quantitative descriptive analysis (QDA). In sensory scaling a trained panel rated the samples for astringency which was expressed as Sensation of Astringency Coefficients (SAC). The QDA was applied for quantitative and qualitative characteristics of the extracts. To determine the content of tannins three spectrophotometric methods were used (n- butanol- HCl hydrolysis, BSA precipitation assay and PVP binding assay). The results proved that both the source of tannins and the type of solvent used for extraction had significant effects on the astringency and sensory profiles of the extracts. The analysis of multiple regression demonstrated that astringency of the extracts examined was affected to the greatest extent by tannins determined with the method of their binding on polyvinylpyrrolidone (PVP) sorbent.

20

Effect of rye bread enriched in green tea extract on body weight gain, visceral fat contents and lipid absorption in rats

67%

Bajerska J., Mildner-Szkudlarz S.

Polish Journal of Food and Nutrition Sciences

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2011

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tom 61

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nr Suppl.1

Ograniczanie wyników

Study of caffeine concentrations in infusions of selected green tea with component of fruit

Actual solubility (S|real.|), level of hydrophilic-lipophilic balance (HLBRequ., HLBD, HLBG) and partition coefficient (log P) of phytochemicals contained in Ext. Camellia sinensis L. aqu. siccum in the light of general Hildebrand- Scatchard-Fedors theory of solubility

The radical scavenging capacity of green tea

The influence of time and type of solvent on efficiency of the extraction of polyphenols from green tea and antioxidant properties obtained extracts

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

Induction of apoptosis in vitro using epigallocatechin-3-gallate [EGCG] in selected tumour cells

The effect of green tea extract on the activity of alcohol dehydrogenase in the liver of rats

Effect of Camellia sinensis extract on the expression level of transcription factors and cytochrome P450 genes coding phase I drug-metabolizing enzymes

Green tea macerate as ingredient in cosmetic emulsions

Rozdzial garbnikow katecholowych roznych gatunkow zielonych i czarnych herbat za pomoca chromatografii kolumnowej