oxidation products
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Oxidation products of natural hydrocarbons rapidly grow pollution nanoparticles to sizes large enough to alter clouds.

Described herewith is an electrochemical method to decontaminate sulphur compounds. Studies were carried out of sulphites (SO32−) oxidation on a range of anode catalysts. The electrocatalysts were characterized by scanning electron microscopy, XRD, XPS and BET. Polarization curves were recorded of electrodes incorporating lyophilized higher fullerenes and manganese oxides. The experiments showed that lyophilized higher fullerenes and C60/C70 fullerene catalysts in conjunction with manganese oxides electrochemically convert sulphites (SO32−) to sulphates (SO42−). The oxidation products do not poison the electrodes. The XPS analysis shows that the catalysts incorporating DWCNTs, MWCNTs and higher fullerenes have a higher concentration of sp3C carbon bonding leading to higher catalytic activity. It is ascertained that higher fullerenes play a major role in the synthesis of more effective catalysts. The electrodes built by incorporating lyophilized catalysts containing higher fullerenes and manganese oxides are shown as most promising in the effective electrochemical decontamination of industrial and natural wastewaters.

We developed ω-3-enriched bread by adding a liposomal polyunsaturated fatty acids (PUFAs) concentrate to the bread recipe. We determined that subsequent feeding of the ω-3-enriched bread to experimental animals in the alimentary dyslipidaemia state led to normalisation of the lipid profile of the blood serum, with a decrease in the total cholesterol, triglycerides, and low-density and very lowdensity lipoproteins. The high-density lipoproteins, antioxidants, reduced glutathione and glutathione reductase activity index increased compared to the corresponding indicators in animals with alimentary dyslipidaemia that were fed bread without ω-3. The ω-3-enriched bread diet significantly decreased harmful oxidation products (diene conjugates and malondialdehyde) in the blood plasma, erythrocytes and liver. Therefore, the results suggested that bread enriched with ω-3 fatty acids is a functional food with hypolipidaemic action. The results on the total content of fatty acids in lipids from bread samples prepared according to a standard recipe and bread enriched with concentrate showed that the relative content of omega-3 PUFAs in the fortified bread significantly increased by 3.2 times compared to bread without the addition of concentrate. The additive did not change the consumer qualities of the finished product (taste and smell of the bread). Keywords: alimentary dyslipidaemia, antioxidant effect, bread, functional food, lipid profile, ω-3 polyunsaturated fatty acids

AbstractIn arson cases, accelerants were usually used by criminals to achieve the purpose of rapid arson. Therefore, fire investigators aim to determine whether accelerants was used in the fire scene. Metallic material has to react with corrosive gas around it at high temperature and the oxidation products may store the information of reactants. Accelerants present in fire scenes impart some oxidative characteristics on metallic materials. The aim of this work is to figure out the possibility to identify the presence of accelerant in a fire according to the oxidation patterns of metallic material. This paper researched the oxidation behavior of mild steel at high temperature in a simulated flame environment. The surface morphological and cross-sectional microstructural features of the samples were characterized by X-ray diffractions, X-ray photoelectron spectroscopy and scanning electron microscopy with energy-dispersive spectroscopy analysis after oxidation. The carbon in the combustion atmosphere had a carburizing effect on the metal oxide layer. It was mostly C–C, C–O and C=O of organic matter could be used as in fire investigation. Various oxidizing atmosphere composite systems promote the formation of metal oxide layers. And bidirectional oxidation mode in the oxide layer further accelerates the oxidation rate. The (wustite) FeO phase was not found in the oxide layer because of the strong oxidation of the combustion atmosphere. These results offer complementary information in fire characteristics, which combining the characterization of surface scale with traditional chemical analysis of recovering ignitable liquid residues from fire debris are expected to offer crucial information for determining the presence of combustion accelerants at a fire scene.

Abstract. Chemical ionization mass spectrometry with nitrate reagent ion (NO3− CIMS) was used to investigate the products of nitrate radical (NO3) initiated oxidation of four monoterpenes in laboratory chamber experiments. α-Pinene, β-pinene, Δ-3-carene, and α-thujene were studied. The major gas-phase species produced in each system were distinctly different, showing the effect of monoterpene structure on the oxidation mechanism and further elucidated the contributions of these species to particle formation and growth. By comparing groupings of products based on ratios of elements in the general formula CwHxNyOz, the relative importance of specific mechanistic pathways (fragmentation, termination, radical rearrangement) can be assessed for each system. Additionally, the measured time series of the highly oxidized reaction products provide insights into the ratio of relative production and loss rates of the high molecular weight products of the Δ-3-carene system. Measured effective O : C ratio of reaction products were anti-correlated to new particle formation intensity and number concentration for each system; however, monomer : dimer ratio of products was positively correlated. Gas phase yields of oxidation products measured by NO3− CIMS correlated with particle number concentrations for each monoterpene system, with the exception of α-thujene, which produced a considerable amount of low volatility products but no particles. Species-resolved wall loss was measured with NO3− CIMS and found to be highly variable among oxidized reaction products in our stainless steel chamber.

Modern dietary habits have created the need for the design and production of functional foods enriched in bioactive compounds for a healthy lifestyle. However, the fate of many of these bioactive compounds in the human gastrointestinal (GI) tract has not been thoroughly investigated. Thus, in the present study, the bioaccessibility of omega-3 fatty acids was examined. To that end, different foods and supplements underwent simulated digestion following the INFOGEST protocol. The selected samples were foods rich in omega-3 fatty acids both in free and bound form—i.e., dietary fish oil supplements, heat-treated fish, and eggs enriched with omega-3 fatty acids. The oxidation of polyunsaturated fatty acids (PUFAs) was measured at each stage of the digestion process using peroxide value (PV) and TBARS and by quantifying individual omega-3 fatty acids using a gas chromatograph with flame ionization detector (GC-FID). The final bioaccessibility values of omega-3 fatty acids were determined. Changes in the quantity of mono-saturated fatty acids (MUFAs) and saturated fatty acids (SFAs) were recorded as well. The results indicated a profound oxidation of omega-3 fatty acids, giving rise to both primary and secondary oxidation products. Additionally, stomach conditions seemed to exert the most significant effect on the oxidation of PUFAs during digestion, significantly decreasing their bioaccessibility. The oxidation rate of each fatty acid was found to be strongly correlated with its initial concentration. Finally, the oxidation pattern was found to be different for each matrix and emulsified lipids seemed to be better protected than non-emulsified lipids. It is concluded that digestion has a profound negative effect on omega-3 bioaccessibility and therefore there is a need for improved protective mechanisms.

The initiation of strawberries into in vitro culture is known to be complicated by the inhibition of organogenesis by phenolic oxidation products. An important role in this process is given to the selection of growth regulators that increase meristematic cell activity and shoot proliferation at the stage of organogenesis induction. The present study aims to obtain a viable apical meristem culture of garden strawberry and to study the effect of different antioxidants (reduced glutathione (RG); a new preparation, i.e., a mechanical composite (MC) on the basis of biogenic silicon and green tea catechins and plant growth regulators (6-benzylaminopurine; thidiazuron) on the initiation of axillary shoot formation in strawberry meristem culture. Terminal buds containing an apical meristem and two leaf primordia isolated from the stolons of two garden strawberry cultivars (Sunny Meadow and Festival Chamomile) were used as primary explants for the initiation of strawberries into in vitro culture. It was found for the first time that the MC exhibits higher antioxidant activity as compared to reduced glutathione, reduces darkening of initial explants, as well as enhancing regeneration up to 13.0% at p ≤ 0.05. Furthermore, the best effect on the formation of microshoots per explant is observed toward the end of material introduction into in vitro culture when combining the MC with growth regulators in the culture medium. Here, the effect of strawberry cultivar on explant regeneration and the number of microshoots per explant are insignificant. It is concluded that the procedure for using the MC as an effective antioxidant during material initiation into the culture can be applied to the large-scale in vitro propagation of garden strawberries. Moreover, the technology for obtaining the MC from plant waste is environmentally friendly, which is a significant advantage for its use in in vitro technologies.

In this manuscript, a series of research reports focused on dietary lipid oxidation products (LOPs), their toxicities and adverse health effects are critically reviewed in order to present a challenge to the mindset supporting, or strongly supporting, the notion that polyunsaturated fatty acid-laden frying oils are “safe” to use for high-temperature frying practises. The generation, physiological fates, and toxicities of less commonly known or documented LOPs, such as epoxy-fatty acids, are also considered. Primarily, an introduction to the sequential autocatalytic peroxidative degradation of unsaturated fatty acids (UFAs) occurring during frying episodes is described, as are the potential adverse health effects posed by the dietary consumption of aldehydic and other LOP toxins formed. In continuance, statistics on the dietary consumption of fried foods by humans are reviewed, with a special consideration of French fries. Subsequently, estimates of human dietary aldehyde intake are critically explored, which unfortunately are limited to acrolein and other lower homologues such as acetaldehyde and formaldehyde. However, a full update on estimates of quantities derived from fried food sources is provided here. Further items reviewed include the biochemical reactivities, metabolism and volatilities of aldehydic LOPs (the latter of which is of critical importance regarding the adverse health effects mediated by the inhalation of cooking/frying oil fumes); their toxicological actions, including sections focussed on governmental health authority tolerable daily intakes, delivery methods and routes employed for assessing such effects in animal model systems, along with problems encountered with the Cramer classification of such toxins. The mutagenicities, genotoxicities, and carcinogenic potential of aldehydes are then reviewed in some detail, and following this the physiological concentrations of aldehydes and their likely dietary sources are considered. Finally, conclusions from this study are drawn, with special reference to requirements for (1) the establishment of tolerable daily intake (TDI) values for a much wider range of aldehydic LOPs, and (2) the performance of future nutritional and epidemiological trials to explore associations between their dietary intake and the incidence and severity of non-communicable chronic diseases (NCDs).

Here we characterize the new Innsbruck wall free impinging jets reactor (INNpinJeR) and compare its performance with the TROPOS free jet flow system by quantifying oxidation products of the well-understood...