This study was focused on in vitro screening of the total antioxidant activity of the selected extracts of the mushroom Coprinus comatus and quinic acid, one of their antidiabetic ingredients, by an uncommon electrochemical assay. Indeed, direct current (DC) polarographic HydroxoPerhydroxo Mercury(II) Complex (HPMC) assay based on decrease of anodic limiting current originating from HPMC formation in alkaline solutions of hydrogen peroxide at potential of mercury dissolution, observed upon gradual addition of antioxidants, was applied herein for the estimation of the natural products' antioxidativity. Quinic acid was found to exhibit most promising antioxidant potential (4.0 ± 0.2%µL−1) being ≈ 2-fold more active than the screened C. comatus extract samples. Actually, such a finding puts some light on the antioxidativity of cyclic polyols, well understimated class of organic compounds, compared to aromatic (poly)phenolics. As a low cost, easy-to handle and accurate this polarographic assay may be thoroughly recommended for much broader use.
12 September 2013 in Journal of Agricultural and Food Chemistry
Red and white wine polyphenols have been reported to provide substantial health benefits. In this study, the cytotoxic activity of red and white wine polyphenolic extracts and of resveratrol was evaluated against different cancer cell lines—human cervix adenocarcinoma HeLa, human breast adenocarcinoma MDA-MB-361, and human breast carcinoma MDA-MB-453—and normal human peripheral blood mononuclear cells (PBMCs). Qualitative and quantitative compositions of wine polyphenolic extracts obtained by fractional vacuum distillation of corresponding wines were determined using spectrophotometric methods and high-performance liquid chromatography with diode array detection and liquid chromatography with electrospray ionization-time of flight mass spectrometry analysis. It was demonstrated that wine polyphenolic extracts and resveratrol exerted higher cytotoxic activity against HeLa and MDA-MB-453 cells in comparison to MDA-MB-361 cells and unstimulated and stimulated PBMCs. Furthermore, white wine polyphenolic extract exhibited a significantly higher antiproliferative action on cancer cell lines than red wine extract. The presence of condensed or fragmented nuclei in HeLa cells, pretreated with extract of white wine and stained with a mixture of acridine orange and ethidium bromide, pointed to the morphological signs of apoptosis. In addition, HeLa cells in late stages of apoptosis or secondary necrosis were also observed. Results from our study suggest that polyphenolic extracts from red and white wine may have anticarcinogenic potential.
This study was focused on in vitro cytotoxicity screening of the raspberry seeds methanol extract towards a number of cancer cell lines of human origin. The tested extract at the preferred concentrations (IC50 300 µg/mL) and non-mutagenic towards normal MRC-5 lung cells. Finally, the extract potently scavenged both OH· (IC50 = 20.11 ± 1.77 µg/mL) and O2-· (IC50 = 47.23 ± 3.82 µg/mL), the free radicals of proved relevance for cancer pathophysiology. Though seeds were enriched with phenolic compounds (TPC = 5.21 ± 0.07 mg GAE/g), anthocyanins were present in traces only (TAC = 0.07 ± 0.003 mg cyn-3-glu/g), while flavonoids were not detected at all. This is the first report on anti-lung cancer potential of the seeds of any soft fruit.