Analysis of green tea extract dietary supplements by micellar electrokinetic chromatography

2006 ◽  
Vol 1117 (1) ◽  
pp. 103-108 ◽  
Author(s):  
David J. Weiss ◽  
Eric J. Austria ◽  
Christopher R. Anderton ◽  
Richard Hompesch ◽  
Ashley Jander
Author(s):  
O. Yu. Maslov ◽  
S. V. Kolisnyk ◽  
M. A. Komisarenko ◽  
A. A. Altukhov ◽  
K. V. Dynnyk ◽  
...  

The aim of the work is to determine and evaluate the antioxidant activity of dietary supplements with green tea extract, as well as to introduce conditional terms of the level of AOA. Materials and methods. The object of the study was dietary supplements of different manufactures: “Green Tea Extract” of Natural Sources, USA (DS1), “Extract of green tea” of Elit-Pharm, Ukraine (DS2) and “Green tea” of Pharmakom, Ukraine (DS3). Potentiometric measurements were conducted by pH meter Hanna 2550 (Germany) with a combined platinum electrode EZDO 5010. Epigallocatechin-3-O-gallate ˃98.0 % (Sigma Aldrich), K3[Fe(CN)6], K4[Fe(CN)6], NaHPO4, KH2PO4 were analytical grade. Results. It was established that a value of the antioxidant activity of DS1 was 36.51 mmol/tab, DS2 – 29.78 mmol/tab, and DS3 – 16.67 mmol/tab. DS1 had the highest value of the antioxidant activity, which correlated with the content of catechins (r2 = 0.9314). According to the proposed conditional terms of antioxidant activity dietary supplements, DS1 and DS2 possessed a low level of antioxidant activity, whereas DS3 corresponded to very low level of antioxidant activity. Conclusions. It was found that the studied dietary supplements with green tea extract have antioxidant activity, which correlates with the content of catechins.


2021 ◽  
Vol 23 (1) ◽  
pp. 132-137
Author(s):  
O. Yu. Maslov ◽  
S. V. Kolisnyk ◽  
O. V. Hrechana ◽  
A. H. Serbin

Recently, there has been a high demand from the population for dietary supplements that have antioxidant activity. First of all, these are dietary supplements with green tea leaf extract, because green tea contains catechins in a fairly high amount. Nowadays, according to the current legislation of Ukraine the qualitative composition and quantitative content of biologically active substances in dietary supplements are not established, which to a certain extent affects the quality and safety of these products. The aim of the study was to determine the qualitative composition and quantitative content of some groups of BAS in dietary supplements with green tea leaf extract. Materials and methods. Three dietary supplements from different manufacturers “Green Tea Extract”, “Green Tea Extract”, “Green Tea” were chosen for the study. Qualitative analysis was performed by thin layer chromatography, for quantification spectrophotometry in the UV-region was used. Results. The presence of catechins was found in the studied dietary supplements, caffeine was found only in trace amounts. The total content of catechins is 146.80 ± 1.36 mg, 79.00 ± 0.88 mg, 28.00 ± 0.75 mg, and in terms of green tea extract, which is stated in dietary supplements for dietary supplements “Green Tea Extract”, “Green Tea Extract”, “Green Tea”, respectively. Conclusions. Qualitative and quantitative analysis of some groups of BAS of three dietary supplements with green tea leaf extract was performed. It was found that dietary supplements “Green Tea Extract” and “Green Tea” meet the requirements of the US Pharmacopoeia 38 in terms of catechins. Based on the study, it can be concluded that the problem of compliance with dietary supplements is relevant today and requires the introduction of regulatory documentation for the detection and determination of biologically active substances in dietary supplements.


Planta Medica ◽  
2011 ◽  
Vol 77 (05) ◽  
Author(s):  
A Ali ◽  
X Yang ◽  
Q Shi ◽  
J Greenhaw ◽  
WF Salminen

2017 ◽  
Vol 23 (4) ◽  
pp. 35-41
Author(s):  
Jeong Hee Park ◽  
Hang Yeon Jeong ◽  
Jeong Yong Cho ◽  
Jae Hak Moon

2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Lisni Noraida Waruwu ◽  
Maria Bintang ◽  
Bambang Pontjo Priosoeryanto

Green tea (Camellia sinensis) is one of traditional plants that have the potential as an anticancer. The sample used in this research commercial green tea extract. The purpose of this study was to test the antiproliferation activity of green tea extract on breast cancer cell MCM-B2 in vitro. Green tea extract fractionated using three solvents, ie water, ethanol 70%, and n-hexane. Extract and fraction of green tea water have value Lethality Concentration 50 (LC50) more than 1000 ppm. The fraction of ethanol 70% and n-hexane had an LC50 value of 883.48 ppm and 600.56 ppm, respectively. The results of the phytochemical screening of green tea extract are flavonoids, tannins, and saponins, while the phytochemical screening results of n-hexane fraction are flavonoids and tannins. Antiproliferation activity was tested on breast cancer cells MCM-B2 and normal cells Vero by trypan blue staining method. The highest MCM-B2 cell inhibitory activity was achieved at a concentration of 13000 ppm green tea extract and 1000 ppm of n-hexane fraction, 59% and 59%, respectively. The extract and n-hexane fraction of green tea are not toxic to normal Vero cells characterized by not inhibiting normal cell proliferation. Keywords: antiproliferative, cancer cell MCM-B2, commercial green tea, cytotoxicity


2020 ◽  
Vol 21 (1) ◽  
pp. 31-35
Author(s):  
Basma El-Desoky ◽  
Shaimaa El-Sayed ◽  
El-Said El-Said

Objective: Investigating the effect of green tea extract (GTE) on the testicular damage induced by cadmium chloride CdCl2 in male rats. Design: Randomized controlled study. Animals: 40 male Wistar rats. Procedures: Rats were randomly divided into four groups: A) control group (each rat daily received pellet diet); B) GTE group each rat daily received pellet diet as well as 3 ml of 1.5 % w/v GTE, C) CdCl2 group each rat was I/P injected a single dose of 1 mg/kg CdCl2, then daily received pellet diet, and D) CdCl2+GTE group each rat was I/P injected a single dose of 1 mg/kg CdCl2 then daily received pellet diet as well as 3 ml of 1.5 % w/v GTE. After 30 days, blood samples were collected for hormonal assays (testosterone, FSH, and LH). In addition, both testes were collected; one of them was used for quantification of 17-beta hydroxysteroid dehydrogenase III (17β-HSDIII) gene expression using a real-time PCR. The other testis was used for determination of catalase and reduced glutathione; GSH, Nitric oxide (NO) and malondialdehyde (MDA) levels. Results: CdCl2 decreased serum testosterone levels and its synthesis pathway (17β-HSDIII testicular gene expression). While antioxidants catalase and GSH were reduced, oxidants MDA were enriched in the testes of CdCl2-poisoned rats. This CdCl2-promoted testicular dysfunction was corrected via the administration of GTE to male rats. Conclusion and clinical relevance: GTE could be used as a remedy for protecting against CdCl2-induced testicular damage in male rats.


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