Phenols

The globally escalating thyroid nodule incidence rates may be only partially ascribed to better diagnostics, allowing for the assessment of environmental risk factors on thyroid disease. Endocrine disruptors or thyroid-disrupting chemicals (TDC) like bisphenol A, phthalates, and polybrominated diphenyl ethers are widely used as plastic additives in consumer products. This comprehensive review studied the magnitude and uncertainty of TDC exposures and their effects on thyroid hormones for sensitive subpopulation groups like pregnant women, infants, and children. Our findings qualitatively suggest the mixed, significant (α = 0.05) TDC associations with natural thyroid hormones (positive or negative sign). Future studies should undertake systematic meta-analyses to elucidate pooled TDC effect estimates on thyroid health indicators and outcomes.

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the present study was to investigate the effects of resveratrol, a polyphenol present in most red wines, on reactive oxygen species formation as well as on arachidonic acid (AA) release, cyclooxygenase expression, and PG synthesis in murine resident peritoneal macrophages. Results show that resveratrol exerted a strong inhibitory effect on superoxide radical (O2−) and hydrogen peroxide (H2O2) produced by macrophages stimulated by lipopolysaccharides (LPS) or phorbol esters (PMA). Resveratrol also significantly decreased [3H]AA release induced by LPS and PMA or by exposure to O2− or H2O2. Resveratrol treatment caused a significant impairment of cyclooxygenase-2 (COX-2) induction stimulated by LPS and PMA or by O2− or H2O2 exposure. These effects of resveratrol on [3H]AA release and COX-2 overexpression were correlated with a marked reduction of PG synthesis. Our results indicate that the antioxidant action of resveratrol affects AA mobilization and COX-2 induction.

Bisphenol A (BPA) is a toxic industrial chemical that affects the endocrine system even at low concentrations. A new method, based on capillary high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS/MS) analysis, has been developed to determine BPA in atmospheric samples. The method involves collection of air samples (typically 2 m3) on glass fiber filters, with ultrasonic extraction and sample concentration under vacuum before analysis. HPLC analysis was performed isocratically at a flow rate of 10 µL min−1 using a capillary reversed-phase column and MS/MS analysis in negative ion multiple reaction monitoring (MRM) mode, using BPA-d16 as internal standard. The present method provides linear response in the range 0.007–3.5 µg/filter (R2 > 0.999) and is characterized by high accuracy (mean bias 2%) and good reproducibility (mean RSD 5%). High sensitivity (LOD = 2 ng/m3 based on 2 m3 of air collected), specificity, and speed of the analysis make the present method suitable for routine determination of BPA in the atmosphere, both for ambient and personnel monitoring. Copyright © 2005 John Wiley & Sons, Ltd.

KATHLEEN M. HESS*, MATTHEW W. DUDLEY*, DAVID G. LYNN*t, ROLF D. JOERGERf, AND ANDREW N. BINNSt *Searle Chemistry Laboratory, 5735 Ellis Avenue, The University of Chicago, Chicago IL 60637; and tPlant Science Institute, Department of Biology, ...

The present work explores antimutagenic and antioxidant potential as well as total phenolics of aqueous and acidified methanol extractable components from clove (Syzygium aromaticum L.) seed. The magnitude of antimutagenic activity of clove seed extracts (CSE) against two mutant bacterial strains: S. typhimurium TA98 and S. typhimurium TA100 (Ames bacterial test) ranged from 34.11-79.74%. Antioxidant activity in terms of measurement of DPPH radical scavenging capacity and inhibition of linoleic acid peroxidation was noted to be 71.16-94.58% and 54.96-86.89%, respectively. CSE also exhibited an appreciable amount of total phenolics with contribution between 22.80 and 115.33 GAE mg/100g. A strong correlation between total phenolics and tested biological activities were recorded. The results of this study advocate that clove seed can be explored as a viable source of bioactives for the development of chemotherapeutic drugs against cancer in addition to acting as nutraceutical and funct...

Phenolic compounds present in berries selectively inhibit the growth of human gastrointestinal pathogens. Especially cranberry, cloudberry, raspberry, strawberry and bilberry possess clear antimicrobial effects against e.g. salmonella and staphylococcus. Complex phenolic polymers, such as ellagitannins, are strong antibacterial agents present in cloudberry, raspberry and strawberry. Berry phenolics seem to affect the growth of different bacterial species with different mechanisms. Adherence of bacteria to epithelial surfaces is a prerequisite for colonization and infection of many pathogens. Antimicrobial activity of berries may also be related to antiadherence activity of the berries. Utilization of enzymes in berry processing increases the amount of phenolics and antimicrobial activity of the berry products. Antimicrobial berry compounds are likely to have many important applications in the future as natural antimicrobial agents for food industry as well as for medicine.

The content of phenolic compounds determines the state of phenolic ripening of red grapes, which is a key criterion in setting the harvest date to produce quality red wines. Wine phenolics are also important quality components that contribute to the color, taste, and mouth feel of wines. Spectroscopic techniques (e.g., near and mid infrared) offer the potential to simplify and reduce the analytical time for a range of grape and wine analytes. It is this characteristic, together with the ability to simultaneously measure several analytes in the same sample at the same time, which makes these techniques very attractive for use in both industry and research. The objective of this mini review is to present examples and to discuss different applications of visible (VIS), near infrared (NIR) and mid infrared (MIR) to assess and measure phenolic compounds in grape and wines.