Zoriţa Diaconeasa

Antiproliferative and Antioxidant Properties of Anthocyanin Rich Extracts from Blueberry and Blackcurrant Juice

The present study was aimed at evaluating the antiproliferative potential of anthocyanin-rich fractions (ARFs) obtained from two commercially available juices (blueberry and blackcurrant juices) on three tumor cell lines; B16F10 (murine melanoma), A2780 (ovarian cancer) and HeLa (cervical cancer). Individual anthocyanin determination, identification and quantification were done using HPLC-MS. Antioxidant activity of the juices was determined through different mechanism methods such as DPPH and ORAC. For biological testing, the juices were purified through C18 cartridges in order to obtain fractions rich in anthocyanins. The major anthocyanins identified were glycosylated cyanidin derivatives. The antiproliferative activity of the fractions was tested using the MTT assay. The antiproliferative potential of ARF was found to be associated with those bioactive molecules, anthocyanins due to their antioxidant potential. The results obtained indicated that both blueberry and blackcurrants are rich sources of antioxidants including anthocyanins and therefore these fruits are highly recommended for daily consumption to prevent numerous degenerative diseases.

Chokeberry Anthocyanin Extract as Pancreatic β-Cell Protectors in Two Models of Induced Oxidative Stress

The aim of this study was to investigate the protective effects of a chokeberry anthocyanin extract (CAE) on pancreatic β-cells (βTC3) exposed to hydrogen peroxide- (H2O2-) and high glucose- (HG-) induced oxidative stress conditions. In order to quantify individual anthocyanins high performance liquid chromatography (HPLC) coupled to photodiode array (PDA) was used. The identification of the fragment ion pattern of anthocyanins was carried out by electrospray ionization mass spectrometry (LC-ESI-MS). The results showed that physiologically achievable concentrations of CAE (1, 5, and 10u2009μM) protect βTC3 against H2O2- and HG-induced cytotoxicity. Antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were increased in pancreatic β-cells pretreated with CAE compared to cells exposed to the prooxidant agents. GSH levels initially reduced after exposure to H2O2 and HG were restored by pretreatment with CAE. Insulin secretion in βTC3 cells was enhanced by CAE pretreatment. CAE restored the insulin pool and diminished the intracellular reactive oxygen species level in glucose-induced stress condition in βTC3 cells. These results demonstrate that anthocyanins from CAE were biologically active, showing a secretagogue potential and an antioxidative protection of enzymatic systems, conferring protection against H2O2 and glucose toxicity in βTC3 cells.

Melanoma Inhibition by Anthocyanins Is Associated with the Reduction of Oxidative Stress Biomarkers and Changes in Mitochondrial Membrane Potential

AbstractAnthocyanins are water soluble pigments which have been proved to exhibit health benefits. Several studies have investigated their effects on several types of cancer, but little attention has been given to melanoma. The phytochemical content of nine different berry samples was assessed by liquid chromatography followed by electrospray ionization mass spectrometry (LC-ESI+-MS). Twenty-six anthocyanins were identified, after a previous C18 Sep-pak clean-up procedure. Chokeberry and red grape anthocyanins rich extracts (C-ARE and RG-ARE) were selected to be tested on normal and melanoma cell lines, due to their different chemical pattern. C-ARE composition consists of cyanidin aglycone glycosylated with different sugars; while RG-ARE contains glucosylated derivatives of five different aglycones. Both C-ARE and RG-ARE anthocyanins reduced proliferation, increased oxidative stress biomarkers and diminished mitochondrial membrane potential in melanoma cells, having no negative influence on normal cells. A synergistic response may be attributed to the five different aglycones present in RG-ARE, which proved to exert greater effects on melanoma cells than the mixture of cyanidin derivatives with different sugars (C-ARE). In conclusion, C-ARE and RG-ARE anthocyanins may inhibit melanoma cell proliferation and increase the level of oxidative stress, with opposite effect on normal cells. Therefore, anthocyanins might be recommended as active ingredients for cosmetic and nutraceutical industry.n Graphical Abstractᅟ

Pharmacologically Active Plant-Derived Natural Products

Abstract A mounting body of evidence strongly supports the theory that natural bioactive compounds (e.g., polyphenols, carotenoids, and stilbenes) present in vegetables and fruits are able to prevent several chronic diseases. However, a large number of bioactive compounds that are linked to health benefits have low stability, are poorly absorbed, and own very limited bioavailability in humans, hindering positive results in clinical applications. Accordingly, a desirable strategy is to enhance their bioavailability or to increase their solubility, stability, and release, by developing efficient delivery systems for oral or topical administration. In this chapter, we focus on some relevant progresses on the development of delivery carriers designed to improve bioavailability of bioactive compounds like polyphenols, carotenoids, and stilbenes, with potential medical applications.

Effects of Extraction Solvents on the Quantification of Free Amino Acids in Lyophilised Brewer’s Yeast

The aim of this work was to test some solvents in order to improve the free amino acids extraction from lyophilised brewer’s yeast. The brewer’ yeast was treated with four types of extraction solvents: Solvent I – acetonitrile 25%/HCl 0.01M (ACN); Solvent II – ethanol 80%; solvent III – HCl 0.05M/deionized water (1/1 volume); Solvent IV – HCl 0.05M/ethanol 80% (1/1 volume). The supernatants were analysed by HPLC-DADESI-MS method. Acetonitrile provided the less quantities and number of amino acids extracted due to its weaker polarity. Solvent II and IV (ethanol, respectively acidified ethanol), which have an increased polarity, extracted 15 amino acids due to the addition of HCl in solvent IV. Solvent III (acidified water) proved to be the best extraction solvent for the amino acids from brewer’s yeast providing the separation of 17 compounds: GLN, ASN, SER, GLY, ALA, ORN, PRO, HIS, LYS, GLU, TRP, LEU, PHE, ILE, AAA, HPHE, TYR.

Resveratrol Modulates Oxidative Status in Rose Bengal Photosensitized Retinal Pigment Epithelial Cells

Eye exposure to high light intensities can produce a photochemical damage to retinal pigment epithelium (RPE), leading to severe pathologies. RPE D407 cells treated with Resveratrol (RSV, 100 μM, 24h) +/photosensitizer Rose Bengal (RB, 500 nM, 1h) were exposed to green LED light. Cell viability and level of intracellular reactive oxygen species (ROS) produced after exposure to green light +/RB were evaluated by MTT, respectively ROS assays. Spectrophotometric methods were used to determine GSH level and enzyme activities (CAT, SOD, GPx). Green LED light alone reduced cell viability with 30%, but a 40% reduction was observed in the presence of RB. RSV proved to have a strong positive impact, with a 20% increase in the viability of D407 cells exposed to green LED light. Viability of D407 cells exposed to green LED light +/+ RB in the presence of RSV remained unchanged comparing to corresponding control. RSV blocked the intracellular ROS production, stimulated or restored the antioxidant enzymes activities and increased the level of reduced GSH in cells exposed to green LED light +/RB. Our data came to support the potential use of RSV as protecting agent of retina’s antioxidant defence system in light-induced stress.