We developed a novel pre-separation method of trans fatty acids (TFAs) using a silver-ion cartridge column and GC. As a preliminary study, a mixture of fatty acid methyl esters consisting of saturated, cis-unsaturated, and trans-unsaturated fatty acids was dissolved in dichloromethane and loaded onto a Bond Elut SCX ion-exchange cartridge column that was converted to the silver-ion form. The column was then eluted with dichloromethane to obtain the saturated fatty acids, dichloromethane/ethyl acetate (90/10) for the trans mono-ene, dichloromethane/ethyl acetate (65/35) for the cis mono-ene, dichloromethane/acetone (60/40) for the trans di-ene, and acetone/acetonitrile (80/20) for the others. Satisfactory separation of the cis/trans isomers was confirmed by GC analysis. To generalize this technique, the elution conditions of the ready-to-use Discovery Ag-ION SPE cartridge column were also optimized. Both cartridge columns had good separation, recovery, and repeatability. Peer laboratory verification was carried out between two laboratories using different production lots of the ready-to-use cartridge column, and the robustness of the product and reproducibility of the method were found to be satisfactory. This technique is therefore a powerful tool not only for routine analyses of TFAs in oils, fats, and foods but also for detailed analyses of TFAs in various research fields.

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A toluene-polyethylene (PE) mixture, only partially miscible at room temperature (RT), was ultrasonically dispersed in hot water, followed by immediate cooling to give a highly stable surfactant-free oil-in-water (O/W) emulsion. This temperature effect was correlated with physical gelation of the bulk mixture. Prolonged stabilization was achieved only through dispersion at a temperature (T_d) above the gelation temperature (T_gel) of the toluene-low-density PE (LDPE) mixture and subsequent rapid cooling. These stabilized emulsions exhibited characteristics such as a small droplet size with a narrow size distribution, low ζ-potential, and round-shaped droplets, which were not observed for the emulsions prepared at T_d < T_gel or those at T_d > T_gel that had been subjected to slow cooling. From these results, physical gelation through crystallization and modification of the droplet surface by PE were concluded to be essential for the prolonged stability of a surfactant-free toluene emulsion.

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In this study, a simple, rapid, and solvent-free method for quantitative determination of (+)-Δ³-carene metabolites released from larvae of Spodoptera litura was developed using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Further, we calibrated and validated the HS-SPME method for the quantitation of the loss of substrates owing to their biotransformation by the larvae. (+)-Δ³-Carene metabolites were extracted at 25°C for 30 min using an SPME fiber over a period of 24 h; the SPME fiber used was made of divinylbenzene-carboxen-polydimethylsiloxane. This technique was used to analyze the time course of the larval headspace, and the results of this analysis were used to propose a metabolic pathway. An external calibration curve was used for the quantification of (+)-Δ³-carene metabolites from the larval headspace. The total release volume of the larvae was calculated at 24 % of the dosage. Moreover, the biotransformation by S. litura began 2 h after it was injected with (+)-Δ³-carene. The method was validated by calculating the limit of detection (LOD), limit of quantification (LOQ), accuracy, precision, and linearity. The LOD and LOQ corresponded to signal/noise ratios of 3 and 10, respectively. The LODs ranged from 0.002 to 0.003 nmol/mL, and the LOQs ranged from 0.007 to 0.009 nmol/mL. This method was sensitive enough to quantitate the (+)-Δ³-carene metabolites released from the Spodoptera larvae. The developed SPME method can have wide applications in various in vivo larval metabolite studies.

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The biochemical properties of carotenoids from 2 species of freshwater bivalve, namely, Unio douglasiae nipponensis and Anodonta lauta, and 2 species of freshwater snail, namely, Cipangopaludina chinensis laeta and Semisulcospira libertina, were investigated. Diatoxanthin and fucoxanthin were identified as major carotenoids in both bivalves. In contrast, lutein and zeaxanthin were found to be the major carotenoids in C. chinensis laeta. In addition, a series of keto carotenoids was also identified in S. libertina.

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The synthesis of 6-O-octanoyl-1,2-O-isopropylidene-α-D-glucofuranose (C8-IpGlc) via the lipase-catalyzed esterification of 1,2-O-isopropylidene-α-D-glucofuranose (IpGlc) with octanoic acid was evaluated using ketones, nitriles, and tertiary alcohols as reaction media. Among the solvents assessed, acetone was the most effective solvent for the synthesis of C8-IpGlc at 50°C, without the formation of a by-product (a diester of IpGlc); the optimum molar ratio of octanoic acid:IpGlc was 2:1. Notwithstanding early-stage substrate inhibition by IpGlc at initial IpGlc concentrations greater than 250 mmol/L, an optimal product concentration of ca. 210 mmol/L (conversion = 53 % at 7 d) was achieved at longer reaction times by changing the initial IpGlc concentration from 25 to 800 mmol/L.

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This study aims to examine methods and the most suitable conditions for producing methyl ester from crude rubber seed oil. An acid esterification-alkaline transesterification process is proposed. In the experiment, the 20% FFA of crude rubber seed oil could be reduced to 3% FFA by acid esterification. The product after esterified was then tranesterified by alkaline transesterification process. By this method, the maximum yield of methyl ester was 90% by mass. The overall consumption of methanol was 10.5:1 by molar ratio. The yielded methyl ester was tested for its fuel properties and met required standards. The major fatty acid methyl ester compositions were analyzed and constituted of methyl linoleate 41.57%, methyl oleate 24.87%, and methyl lonolenate 15.16%. Therefore, the cetane number of methyl ester could be estimated as 47.85, while the tested result of motor cetane number was 51.20.

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Supplementation of the diet with Peucedanum japonicum Thunb (PJT) powder inhibits high-fat diet-induced obesity in mice. Either the fiber component or other bioactive components in the PJT powder may inhibit obesity. This study, therefore, was an attempt to identify the components, fiber or other phytochemicals of PJT that were responsible for the anti-obesity activity, and also studied the modulation of obesity-related gene expression in C57BL/6 mice. Animals were fed a modified-AIN76 diet supplemented with PJT powder or extracts of PJT in water, 50 % ethanol, or ethanol. Body weight gain, tissue weight, serum biochemical parameters, liver lipid concentrations, and gene expression in tissues were compared between the control and treatment groups. Of the extracts, the ethanol extract of PJT decreased fat accumulation and adipocyte size, reduced serum and liver triglyceride concentrations, and inhibited obesity. This finding clearly demonstrates the presence of anti-obesity phytochemicals in PJT. Ethanol extract of PJT inhibited lipase activity in vitro. Modulation of gene expression by PJT ethanol extract was largely similar to that by PJT powder in the hepatic and adipose tissues: RORC and PBEF1 were upregulated and DUSP1, INSIG2, and SERPINA12 were downregulated in the liver; FXRα and PPARγ were upregulated and PEG1/MEST, the size-marker of adipocytes, was downregulated in the adipose tissue. Furthermore, PJT ethanol extract increased the expression of the UCP3 gene in muscle. These results suggest that the anti-obesity phytochemicals in PJT lower lipid levels by inhibiting fat absorption and by modulating obesity-related gene expression in the liver, adipose tissue, and muscle.

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The effect of consumption of fatty acids and selected nutrients, along with regular physical activity, on cardiovascular risk factors in rats was investigated.
Male rats were divided into the seven groups: Group 1: regular food and drinking water, Group 2: same as Group. 1 + physical activity (whole body vibration; WBV), Group 3: same as Group. 2 + calcium, vitamin D, boron, Group 4: same as Group. 3 + canola oil, Group 5: same as Group. 3 + sunflower oil, Group 6: same as Group. 3 + mix of sunflower oil and canola oil, Group 7: same as Group. 3 + coconut oil. Rats were treated for 8 weeks, and analysis of the frozen plasmas was performed. A- Analysis between the treatment groups and control revealed that vibration training in Group 2 increased body weight (P = 0.04), plasma creatin kinase (CK), (P = 0.02), and estradiol (E2), (P = 0.03). Rats in Group 5 consumed less food and plasma levels of cholesterol and LDL-cholesterol (LDL-C) increased significantly (P = 0.02) in Group 6 and in Group 7 (p<0.05). B- Analysis of data among Group 4 - 7 (the oil consuming groups) and Group 3 revealed significant differences in cholesterol (Chol), LDL-C, HDL-cholesterol (HDL-C), triglycerides (TG), C- reactive protein (hs-CRP), estradiol (E2), atherogenic index (AI), and risk factor (RF), (p<0.05). In addition, plasma levels of testosterone (T) and free testosterone (FT) in Group 7 had a remarkable but non-significant increase. As a result of vibration training, a similar trend was observed for vitamin D in Group 2-7. The findings show that WBV is effective in improving health status by influencing cardiovascular disease (CVD) risk factors. Moreover, canola oil and sunflower oil, separately, showed beneficial impacts on CVD risk factors; whereas their combination had negative impacts on lipid profile. Coconut oil revealed to be efficient to provide health benefits in terms of CVD treatments.

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