Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Correlation of odor and color profiles of oysters (Crassostrea virginica) with electronic nose and color machine vision

WOS: 000221403900020Odor and color changes in oysters (Crassostrea virginica) stored at 1.8degrees and 7degreesC were measured every 3 days for up to 13 days with an electronic nose. a computer vision system, and sensory panels. Electronic nose and odor sensory data was analyzed using Discriminant Function Analysis (DFA). Correct classification rates of 100% were obtained to group electronic nose data by days and sensory scores at each temperature. When all temperature and days data were pooled, DFA predicted sensory scores based on electronic nose readings with 94% accuracy. Oyster colors were analyzed using the 512 color block scheme. Eight colors were found to be significant. The correlations of these colors, as well as the average L*a*b* values with time and with color sensory data suggested prediction of color quality. This study suggests that electronic nose and color vision could be used to objectively evaluate the quality of oysters

Classification of impacted blueberries during storage using an electronic nose

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)BACKGROUND: An electronic nose (EN) was used to determine the effect of repeated impacts on changes in volatile characteristics of fresh blueberries during storage. Hand-harvested 'Misty' blueberries (Vaccinium corymbosum) were treated either as (1) undropped (control) fruits, (2) fruits poured six times from a picking bucket 200 mm into a plastic field lug or (3) fruits dropped as above ten times onto a steel surface. Fruits from all treatments were stored in vented polystyrene clamshell containers at 2 degrees C and 95% relative humidity. RESULTS: Repeated impacts caused no skin rupture or leakage after treatment or during storage. EN data were subjected to discriminant function analysis to classify samples by treatment at days 0, 2, 10, 17 and 24 (n = 5 per treatment). Correct classification rates (CCRs) for days 0, 2, 10, 17 and 24 were 0, 100, 100, 100 and 100% respectively. On day 0 there was no significant difference in sample volatiles, and CCRs for all treatments and storage times ranged from 80 to 100%. Cross-validation rates for different treatments and storage times ranged from 75 to 100%. CONCLUSION: The EN could be a useful tool to estimate the effect of impacts incurred during blueberry handling on quality based on changes in volatile characteristics. (C) 2011 Society of Chemical Industry91917221727State University of Campinas (UNICAMP), BrazilFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Effects of dense phase carbon dioxide pasteurization on the physical and quality attributes of a red grapefruit juice

ABSTRACT: Red grapefruit juice was treated with continuous dense phase carbon dioxide (DPCD) equipment to inactivate yeasts and molds and total aerobic microorganisms. A central composite design was used with pressure (13.8, 24.1, and 34.5 MPa) and residence time (5, 7, and 9 min) as variables at constant temperature (40 ◦C), and CO2 level (5.7%) after experimentallymeasuring CO2 solubility in the juice. Five log reduction for yeasts and molds and total aerobicmicroorganisms occurred at 34.5 MPa and 7 min of treatment. A storage study was performed on the fresh juice DPCD treated at these conditions. ◦Brix, pH, titratable acidity (TA), pectinesterase (PE) inactivation, cloud, color, hue tint and color density, total phenolics, antioxidant capacity, and ascorbic acid weremeasured after the treatment and during 6 wk storage at 4 ◦C. During storage, the DPCD-treated juice showed no growth of total aerobic microorganisms and yeasts and molds. Cloud increased (91%) while percent PE inactivation was partial (69.17%). No significant (α = 0.05) differences were detected between treated and untreated samples for ◦Brix, pH, and TA. Treated juice had higher lightness and redness and lower yellowness. No significant differences (α = 0.05) were detected for the hue tint values while the color density value was higher for the treated samples compared to the untreated. The treatment and the storage did not affect the total phenolic content of the juice. Slight differences were detected for the ascorbic acid content and the antioxidant capacity. The experimental results showed evidence that the treatment canmaintain the physical and quality attributes of the juice, extending its shelf life and safety

π-electron content of rings in polycyclic conjugated compounds – A valence bond based measure of local aromaticity

© 2017 Elsevier B.V. In 2004 Randić and Balaban employed Kekulé structures to assess the π-electron content (EC) of rings in benzenoid hydrocarbons. In this paper we showed how ab initio Valence Bond (VB) calculations based on the set of Kekulé structures of a given polycyclic conjugated molecule can be used to obtain more accurate π-electron contents of rings (VB-EC) as the true computed weights of the Kekulé structures are used, instead of postulating that all Kekulé structures have equal weights as in the EC formula. In the case of benzenoid hydrocarbons, the values of VB-EC and EC are very close. The main difference is found for linear polyacenes, for which, contrary to the EC, the VB-EC values predict that the inner rings are more aromatic than the terminal rings. The original EC method has also the disadvantage that it cannot be applied to heterocyclic conjugated molecules. It was shown that the VB-EC method can be used to assess the local aromaticity in aza derivatives of naphthalene. The calculated VB-EC values were compared with several other aromaticity indices, namely: energy effect (ef), harmonic oscillator model of aromaticity (HOMA) index, six center delocalization index (SCI) and nucleus independent chemical shifts (NICS). The best correlation was found between the VB-EC and SCI, implying that these two indices carry similar information on the local aromaticity