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Hagen R.M.,University of the West of England | Chedea V.S.,University of the West of England | Chedea V.S.,National Research Development Institute for Animal Biology and Nutrition IBNA | Mintoff C.P.,University of the West of England | And 3 more authors.
International Journal of Oncology | Year: 2013

Growing evidence suggests that the flavonoid epigallocatechin-3-gallate (EGCG), notably abundant in green tea, has health-promoting properties. We examined the effect of EGCG on cell survival and apoptosis in the prostate cancer cell line PC3. Cell survival was reduced and apoptosis increased significantly with a low dose of 1 μM EGCG. The ability of the anticancer drug cisplatin to promote apoptosis was enhanced by EGCG. Furthermore, EGCG, both alone and in combination with cisplatin, promoted the expression of the pro-apoptotic splice isoform of caspase 9.

Choueiri L.,Mediterranean Agronomic Institute of Chania | Chedea V.S.,National Research Development Institute for Animal Biology and Nutrition IBNA | Calokerinos A.,National and Kapodistrian University of Athens | Kefalas P.,Mediterranean Agronomic Institute of Chania
Food Chemistry | Year: 2012

The behaviour of four known antioxidants (quercetin, ascorbic acid, catechin and caffeic acid) and their mixtures at different molar ratios was studied in view of elaborating predictions over an eventual pro-oxidant or synergistic antioxidant activity. The Co(II)-EDTA luminol chemiluminescence showed that the mixture of quercetin and ascorbic acid at ratio 2:1 had the most pronounced antioxidant activity, while that of quercetin and caffeic acid at ratio 1:2 showed the least antioxidant activity, which may be interpreted as a strong propensity for pro-oxidant behaviour. The LC-MS analysis for the two mixtures revealed a significant amount of unoxidised quercetin in the case of quercetin with ascorbic acid, whereas in the case of quercetin with caffeic acid this amount was negligible. This observation supports the fact that the first combination was more antioxidant than the second, through efficient quercetin recycling (reduction of the quinone by ascorbic acid; redox cycling of quinones). © 2012 Elsevier Ltd. All rights reserved.

Braicu C.,Oncological Institute Prof Dr Ion Chiricuta | Braicu C.,University of Medicine and Pharmacy, Cluj-Napoca | Ladomery M.R.,University of the West of England | Chedea V.S.,National Research Development Institute for Animal Biology and Nutrition IBNA | And 5 more authors.
Food Chemistry | Year: 2013

Catechins and their gallate esters are a class of polyphenolic compounds. The catechin subclass known as flavan-3-ols have recently attracted much attention with regards to their beneficial effect on human health. Their biological actions are dependent on the structure of the compounds and vary according to cell type. They are best known as powerful antioxidants; however depending on the doses they also exhibit prooxidant effects. The anti- or prooxidant effects of green tea catechins have been implicated in the modulation of several cellular functions often associated with strong chemoprotective properties. This review summarises the benefit catechins to human health, the main molecular pathways modulated by catechins. The relationship between the structure and activity of the catechins needs to be studied further. In the future, the structure of catechins could be modified so as to synthesise novel compounds with more specific beneficial properties and higher bioavailability. © 2013 Elsevier Ltd. All rights reserved.

Chedea V.S.,National Research Development Institute for Animal Biology and Nutrition IBNA | Braicu C.,University of Medicine and Pharmacy, Cluj-Napoca | Chiril F.,University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca | Ogola H.J.O.,Jaramogi Oginga Odinga University of Science and Technology | And 3 more authors.
BioMed Research International | Year: 2014

In an attempt to determine the antioxidant/prooxidant, antibacterial/probacterial action of flavan-3-ols and procyanidins from grape seeds, pure catechin (CS), and an aqueous grape seed extract (PE), were applied in the absence and presence of pure lipoxygenase (LS) or in extract (LE) to leucocyte culture, Escherichia coli B41 and Brevibacterium linens, and observed whether there was any effect on lipid peroxidation, cytotoxicity, or growth rate. Short time periods of coincubation of cells with the polyphenols, followed by the exposure to LS and LE, revealed a high level of lipid peroxidation and a prooxidative effect. Longer coincubation and addition of LS and LE resulted in the reversal of the prooxidant action either to antioxidant activity for CS + LS and PE + LS or to the control level for CS + LE and PE + LE. Lipid peroxidation was significantly reduced when cells were exposed to polyphenols over a longer period. Longer exposure of E. coli to CS or PE followed by addition of LS for 3 h resulted in bactericidal activity. Significant stimulatory effect on microbial growth was observed for PE + LS and PE + LE treatments in B. linens, illustrating the potential probacterial activity in B. linens cultures. Lipoxygenase-polyphenols complex formation was found to be responsible for the observed effects. © 2014 Veronica Sanda Chedea et al.

Varzaru I.,University of Bucharest | Untea A.E.,National Research Development Institute for Animal Biology and Nutrition IBNA | Van I.,University of Bucharest
Romanian Biotechnological Letters | Year: 2015

Several bioactive compounds from plants like Chelidonium majus, Equisetum arvense and Hypericum perforatum are well known for their potential benefic effects on human and animal health. However, few data on the effect of these plants on various ocular diseases, such as age-related macular degeneration (AMD), cataracts, glaucoma have been reported. The purpose of this study was to investigate the content of several bioactive compounds (lutein and zeaxanthin, vitamin E and zinc) from twelve medicinal plants, known for their antioxidant activity. Four of these herbs are known for their pharmacological effects in inflammatory eye disorders, and the rest of them are plants with yellow flowers recommended in treatments of other diseases like cardiovascular, liver, skin, nervous disorders. The plants characterization regarding the lutein and zeaxanthin content was performed by developing and validating a HPLC method. The processing of the results was done using the Multi-Criteria Decision Analysis (MDCA) in order to make choices taking into account multiple criteria simultaneously. The results of the study showed that Calendula officinalis, Chelidonium majus, Equisetum arvense and Hypericum perforatum were the plants with the four highest total ranking scores, the last three of them not being used in treating eye disorders. Calendula officinalis had 5.239 ± 0.19 mg/100 g lutein and zeaxanthin, 168.68 ± 5.06 μg/mL vitamin E and 32.13 ± 0.73 μg/mL Zn. These results provide scientific support for using these plants in the treatment of eye disorders. © 2015 University of Bucharest.

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