Explore the vast range of titles available.

Resveratrol (RSV) is a natural polyphenol that is known as a powerful chemopreventive and chemotherapeutic anticancer molecule. This study focused on the effects of RSV on the activities and expression levels of antioxidant enzymes in the cancer cells. Prostate cancer PC-3 cells, hepatic cancer HepG2 cells, breast cancer MCF-7 cells and the non-cancerous HEK293T kidney epithelial cells were treated with a wide range of RSV concentrations (10-100 μM) for 24-72 h. Cell growth was estimated by trypan blue staining, activities of the antioxidant enzymes were measured spectrophotometrically, expression levels of the antioxidant enzymes were quantified by digitalizing the protein band intensities on Western blots, and the percentage of apoptotic cells was determined by flow cytometry. Treatment with a low concentration of RSV (25 μM) significantly increased superoxide dismutase (SOD) activity in PC-3, HepG2 and MCF-7 cells, but not in HEK293T cells. Catalase (CAT) activity was increased in HepG2 cells, but no effect was found on glutathione peroxidase (GPX) upon RSV treatment. RSV-induced SOD2 expression was observed in cancer cells, although the expression of SOD1, CAT and GPX1 was unaffected. Apoptosis increased upon RSV treatment of cancer cells, especially in PC-3 and HepG2 cells. Together, our data demonstrated that RSV inhibits cancer cell growth with minimal effects on non-cancerous cells. We postulate that the disproportional up-regulation of SOD, CAT and GPX expression and enzymatic activity in cancer cells results in the mitochondrial accumulation of H2O2, which in turn induces cancer cell apoptosis.

The aim of this study was to prepare some phenolic acids alkyl esters (methyl, ethyl, propyl, butyl and hexyl) and to determine their antioxidant and antimicrobial activities. The antimicrobial activity against Escherichia coli DMF 7503, Bacillus cereus DMF 2001, Listeria monocytogenes DMF 5776, Fusarium culmorum DMF 0103, and Saccharomyces cerevisiae DMF 1017 was investigated and expressed by minimum inhibitory concentration (MIC) in the range of 1.2-20mM. The inhibitory activity of phenolic acids butyl esters was found to be higher than that of methyl esters (MIC below 1.25mM). The antioxidant activity of the selected phenolic acids alkyl esters was investigated by Rancimat method. The esters of 3,4-dihydroxyphenolic acids (protocatechuic and caffeic acids) exhibited higher antioxidant activities in comparison with the respective phenolic acids. The highest antioxidant activity was found in the case of caffeic alkyl esters.

The effect of temperature on the antioxidant activity of phenolic acids (gallic, gentisic, protocatechuic, syringic, vanillic, ferulic, caffeic, and sinapic; 0.5 mmol/kg) was studied in pork lard, using an Oxipres apparatus, at a temperature range of 90 deg C to 150 deg C. The antioxidant activity of all studied compounds decreased with increasing working temperature, whereas a linear relationship (P less than 0.01) existed between temperature and the antioxidant activity in all cases. However, the relative rate of the antioxidant activity decrease with increasing temperature (i.e. in comparison with the activity at 90 deg C) was not the same for all studied phenolic acids. Easily oxidisable phenolic acids (i.e. gallic, gentisic, protocatechuic, and caffeic) showed a slower decrease in antioxidant activity with increasing temperature (in comparison with their activity at 90 deg C) than the less oxidisable ones (i.e. syringic, ferulic and sinapic acids, and especially vanillic acid). Consequently, only gallic, gentisic, protocatechuic, and caffeic acids showed a significant antioxidant activity at 150 deg C and vanillic acid was active only at 90 deg C.

Resveratrol is a plant phenolic phytoalexin that has been reported to have antitumor properties in several types of cancers. In particular, several studies have suggested that resveratrol exerts antiproliferative effects against A549 human non-small cell lung cancer cells; however, its mechanism of action remains incompletely understood. Deregulation of microRNAs (miRNAs), a class of small, noncoding, regulatory RNA molecules involved in gene expression, is strongly correlated with lung cancer. In this study, we demonstrated that resveratrol treatment altered miRNA expression in A549 cells. Using microarray analysis, we identified 71 miRNAs exhibiting greater than 2-fold expression changes in resveratrol-treated cells relative to their expression levels in untreated cells. Furthermore, we identified target genes related to apoptosis, cell cycle regulation, cell proliferation, and differentiation using a miRNA target-prediction program. In conclusion, our data demonstrate that resveratrol induces considerable changes in the miRNA expression profiles of A549 cells, suggesting a novel approach for studying the anticancer mechanisms of resveratrol.

Pleurotus eous is a pink edible oyster mushroom cultivated in Coimbatore. The aim of present study was to evaluate antioxidant potential of ethyl acetate, methanol, and hot water extracts from P. eous using various in vitro ROS/RNS generated chemical and biological models. Results demonstrated that the graded-dose (2–50 mg/mL) of various extracts markedly scavenged the DPPH, ABTS, and hydroxyl radicals, and showed metal chelating ability, reducing capacity in Fe3+/ferricyanide complex, and ferric reducing antioxidant power assays. In biological models, different extracts were found to inhibit lipid peroxidation in brain and liver homogenate. Total antioxidant activity was high in methanolic extract. Hot water extract showed higher amount of total phenol and methanolic extract showed higher amount of flavonoid as compared to other extracts. Based on EC50 values it can be concluded that the various extracts from P. eous were good in antioxidant properties with methanol and ethyl acetate extracts being more effective. The results of this study showed that various extracts could serve as natural antioxidants owing to their significant antioxidant activity.

We described the in vitro antioxidant and antimicrobial activities of ethanol, acetone, and water extracts of beet root pomace. Total contents of phenolics (316.30-564.50 mg GAE/g of dry extract), flavonoids (316.30-564.50 mg RE/g of dry extract), betacyanins (18.78-24.18 mg/g of dry extract), and betaxanthins (11.19-22.90 mg/g of dry extract) after solid-phase extraction were determined spectrophotometrically. The antioxidant activity was determined by measuring the reducing power and DPPH scavenging activity by spectrometric method, and hydroxyl and superoxide anion radical scavenging activity by ESR spectroscopy. In general, the reducing power of all the beet root pomace extracts increased with increasing concentrations. The DPPH-free radical scavenging activity of the extracts, expressed as EC50, ranged from 0.133 mg/mL to 0.275 mg/mL. Significant correlation was observed between all phytochemical components and scavenging activity. Ethanol extract (0.5 mg/mL) completely eliminated hydroxyl radical which had been generated in Fenton system, while the same concentration of this extract scavenged 75% of superoxide anion radicals. In antibacterial tests, Staphylococcus aureus and Bacillus cereus showed higher susceptibility than Escherichia coli and Pseudomonas aeruginosa.

Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65% ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity - determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS center dot+) found for TFM - were significantly (P less than 0.05) higher on the 5∨th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities.

Chlorogenic acid, epicatechin, procyanidin B2 and C1 were isolated from apple skin. These compounds as well as quercetine and phloretine glycosides isolated from apples were studied individually and as mixtures for their participation in the enzymatic browning reactions. The importance of quercetine glycosides and the synergistic effect of phloridzin and phloretine xyloglucoside with chlorogenic acid and flavans in the browning reaction are reported

An efficient ultrasound-assisted extraction (UAE) technique was applied to extract total phenolic content (TPC) from yarrow (Achillea beibrestinii). A response surface methodology was employed to evaluate the effects of 4 independent variables (temperature, pH, solvent to sample ratio, and time) on the TPC. The optimum extraction conditions were as follows: liquid to solid ratio 20, pH 6.3, extraction temperature 35°C, and extraction time 35 min. Under the above-mentioned conditions, the experimental TPC was 11.7 mg gallic acid equivalent/g dry matter. EC50 of the UAE extract at optimal conditions was found at 30.6±0.6 mg/L level and total flavonoids (TF) were obtained at 12.6±0.2 mg/10 g sample. Also, the results of HPLC analysis showed that gallic acid and p-coumaric acid were the predominant phenolic compounds in the plant.