High‐Purity Tocored Improves the Stability of Stripped Corn Oil Under Accelerated Conditions

γ‐Tocopherol‐5,6‐quinone (tocored) is of importance among the γ‐tocopherol (γ‐T) oxidant products and found in corn germ oil. Investigation on tocored is impeded in part by the difficulty to access high purity tocored. In this present study, high‐purity tocored is successfully prepared, and its antioxidant activity, together with γ‐T and TBHQ (positive control) in increasing concentrations in stripped corn germ oil is evaluated by Rancimat and Schaal oven tests. The stabilization factor in the Rancimat tests increases significantly (p < 0.05) along with an increase in the levels of antioxidants. Furthermore, tocored exhibits higher stabilization than γ‐T in the Schaal oven tests, although its efficacy gradually increases up to 100 mg kg^–1 and decreases significantly at higher levels (from 100 to 500 mg kg^–1), drawn from the comprehensive parameter A (considering both efficiency and strength) changes (5.06–11.21). In addition, the curves illustrating the residual contents of tocored and γ‐T run in different ways when the four levels are taken into consideration, further bearing the above results. Tocored tends to be a potent natural antioxidant for edible corn germ oil preservation. Practical Application: The present work provides more clear procedures for high‐purity tocored synthesis. Furthermore, tocored may be a potential natural antioxidant that is especially suitable for lipid base food substrates. The results of the present work contribute to the deeper understanding of the antioxidant activity of γ‐tocopherol. The antioxidant activity of tocored is higher than γ‐tocopherol in Schaal oven test. Tocored is a bright orange‐red substance that affects the appearance of the edible oil. Meanwhile, γ‐tocopherol is well known for its valuable health benefits, and appropriate measures should be adopted to store oils (corn oil, soybean oil, and so on) rich in γ‐tocopherol to control transformation in order to keep stability optimal. To some degree, the practical applications of the present results are also related to the processing and storage of edible oils.     

Community response to environmental noise and the impact on cardiovascular risk score

Objective

The objective of our study was to investigate and evaluate the relationship between road traffic noise and cardiovascular risk.

Methods

The study sample (n = 659; 36.9% male, 63.1% female university students, mean age 22.83 ± 1.58 years) included a group exposed to road traffic noise (n = 280, L_eq,24 h = 67 ± 2 dB(A)) and a control group (n = 379, L_eq,24 h = 58.7 ± 6 dB(A)). Subjective response was determined by a validated noise annoyance questionnaire. The ten year risk of developing a coronary heart disease event was quantified as an evaluation of cardiovascular risk (SCORE60, Framingham 10-year risk estimation and projection to the age of 60, relative risk SCORE chart).

Results

Cardiovascular risk scores were significantly higher in the exposed group based on the Framingham scores projected to the age of 60, SCORE60 (AOR = 2.72 (95% CI = 1.21-6.15)) and the relative risk SCORE chart (AOR = 2.81 (1.46-5.41)).

Conclusions

These findings highlight the association between road traffic noise and cardiovascular risk.     

MCFA alleviate H2O2-induced oxidative stress in AML12 cells via the ERK1/2/Nrf2 pathway

Oxidative stress is an important factor in the occurrence and development of liver disease. Medium-chain fatty acids (MCFAs) have potential antioxidant function, whereas the exact underlying mechanism of MCFA in oxidative injury of hepatocytes remains unclear. In our present study, three different MCFAs, 8-carbon octanoic acid (OA), 10-carbon capric acid (CA), and 12-carbon lauric acid (LA), have been performed to observe their protective action for hepatocyte under the H₂O₂ challenge. The result showed that MCFA treatment significantly increased the cell viability, T-AOC, and expression of antioxidant-related genes in AML12 cells under oxidative stress condition, and reduced reactive oxygen species (ROS) production. Moreover, MCFA treatment significantly increased the protein expression of Nrf2 and the phosphorylation level of ERK1/2; LA treatment significantly promoted the Nrf2 nuclear translocation. With a further test, the rescue ability of MCFA was blocked by treating with the ERK inhibitor U0126. Overall, our data suggested that MCFA treatment has positive impact on protecting AML12 cells against oxidative stress through ERK1/2/Nrf2 pathway.     

Rapid Quantification of Low-Viscosity Acetyl-Triacylglycerols Using Electrospray Ionization Mass Spectrometry

Acetyl‐triacylglycerols (acetyl‐TAG) possess an sn‐3 acetate group, which confers useful chemical and physical properties to these unusual triacylglycerols (TAG). Current methods for quantification of acetyl‐TAG are time consuming and do not provide any information on the molecular species profile. Electrospray ionization mass spectrometry (ESI–MS)‐based methods can overcome these drawbacks. However, the ESI–MS signal intensity for TAG depends on the aliphatic chain length and unsaturation index of the molecule. Therefore response factors for different molecular species need to be determined before any quantification. The effects of the chain length and the number of double‐bonds of the sn‐1/2 acyl groups on the signal intensity for the neutral loss of short chain length sn‐3 groups were quantified using a series of synthesized sn‐3 specific structured TAG. The signal intensity for the neutral loss of the sn‐3 acyl group was found to negatively correlated with the aliphatic chain length and unsaturation index of the sn‐1/2 acyl groups. The signal intensity of the neutral loss of the sn‐3 acyl group was also negatively correlated with the size of that chain. Further, the position of the group undergoing neutral loss was also important, with the signal from an sn‐2 acyl group much lower than that from one located at sn‐3. Response factors obtained from these analyses were used to develop a method for the absolute quantification of acetyl‐TAG. The increased sensitivity of this ESI–MS‐based approach allowed successful quantification of acetyl‐TAG in various biological settings, including the products of in vitro enzyme activity assays.     

A review on conversion of triglycerides to on‐specification diesel fuels without additional inputs

Dependence on fossil fuels for global energy supply has continued to generate concerns about climate change and sustainable development. It has motivated the search for carbon‐neutral alternative resources for the production of transportation fuels to replace crude oil. Although biodiesels have recently emerged as a close substitute to petrol diesel, their use in compression ignition engines designed to run on petro‐diesel fuels are linked to adverse effects on the engines' performance and life span. This informed efforts at upgrading biodiesel or direct conversion of triglycerides to hydrocarbon mixtures that are identical or similar to that of petro‐diesel through hydrodeoxygenation. Moreover, it seems that commercial methods for the conversion of triglycerides to diesel fuels depends on inputs (methanol and hydrogen) derived from fossil fuels. However, it will be desirable to do so without inputs from fossil fuels. Hence, reaction paths for direct conversion of triglycerides to on‐specification hydrocarbons fuels without hydrogen gas input are discussed and suggested strategies are in cognisance of green chemistry principles. Copyright © 2012 John Wiley & Sons, Ltd.     

Workload, control, and social support effects on serum lipids: A longitudinal study among apparently healthy employed adults.

The authors investigated the direct and interactive effects of the job demand– control–support (JDC-S) model’s components on subsequent changes in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides (TRI) separately for male and female employees. In contrast to all 14 past studies on these relationships, the authors used a longitudinal design. Study participants (N = 1,137, 66% men) were all apparently healthy employees who underwent a routine health check at 2 points in time (Time 1 and Time 2) about 22 months apart. In these analyses, the authors controlled for the Time 1 level of each criterion and for other confounders. Most of the direct and moderating effects found did not support the predictions of the JDC-S model; this finding is in agreement with the majority of past cross-sectional studies. The authors did not find any evidence supporting the existence of a reverse causation for either of the components of the JDC-S model. The authors suggest that serum lipids may not be a physiological mechanism mediating the effects of the JDC-S model on atherosclerotic diseases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Convenient thionation of triglycerides with lawessons reagent

Thionation using the Lawesson’s reagent (LR) led to quantitative and selective replacement of carbonyl groups (C=O) with thionocarbonyl groups (C=S). Mixtures of thionotriglycerides were obtained by reaction of 2,4-bis (p-methoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide in suspension with triglycerides (TG). With a molar ratio (LR)/(TG)=3∶2, there was complete exchange of C=O with C=S in the carboxylic groups of the TG. The yield is over 90%. The two P=S ligands in the LR confer a double reactivity, producing a high power of thionation. Fourier transform infrared spectroscopy was employed for quantitative and qualitative characterization of the thionated TG and for monitoring the progress of partial or total thionation as conditioned by the molar ratios of the starting compounds. Thus, with molar ration LR/TG of 0.108, 0.36, and 0.72, we obtained around 6, 20, and 40% of C=O conversion, respectively.