Triacylglycerol (TAG) composition in vegetable oils was collaboratively analyzed in 9 laboratories using high-performance liquid chromatography (HPLC) equipped with a refractive index detector. Dococyl (C22) and triacontyl (C30) silica columns were used for analysis. The TAG molecular species in soybean, rapeseed, and palm oils were individually separated on the chromatogram. The collaborative study demonstrated that TAG composition in vegetable oils could be analyzed based on partition numbers (PN) between 38 and 50. In conclusion, the HPLC method using C22 and C30 silica columns would be useful for determining the TAG composition (%) in vegetable oils.

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Lifestyle-related diseases arise from obesity in 30 – 60% of cases. In recent years, food functions controlling the nutritional physiology of lipids have been a focus of disease prevention. Animal feeding experiments have revealed that esters made from gallic acid (GA) and (-)-epigallo-catechin (EGC) or linoleyl alcohol are more effective in weight-loss promotion and metabolic syndrome management than are intact GA and EGC. In this study, an ester (DOGGA) was chemically synthesized from GA and 1,2-dioleoyl glycerol and its effect was compared to that of octyl gallate (OG) and GA in male Wistar rats fed a powdered standard diet containing 7% frying oil for 12 weeks. Results revealed remarkably low body weight gains and food efficiency ratios in the DOGGA group, and the effects of OG were less pronounced than those of DOGGA. The GA group showed no difference from the control group. In addition, fecal lipid content in the DOGGA group was statistically higher than that in the control group, although organ weights and serum biochemical analyses did not differ between the groups. In conclusion, the data suggested that DOGGA promoted weight-loss more effectively than OG and GA did and that the alcohol moiety of gallate is not necessarily EGC and linoleyl alcohol.

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Fatty acids of Euterpe oleracea Mart seeds were analyzed in hexane and diethyl ether extracts. The hexane extract contained dodecanoic acid (3), tetradecanoic acid (4), hexadecanoic acid (7), and 9-octadecenoic acid (10). The diethyl ether extract contained (10). The oil of Mart seeds was obtained firstly by methanol extract and further extracted with diethyl ether. The hexane and diethyl ether extracts were then analyzed for antioxidant effects. Both extracts demonstrated a 1,1-diphenyl-2-picrylhydrazyl radical elimination effect similar to that of α-tocopherol and an active oxygen inhibition effect. Significant quantities (0.6212 mg/mL) of polyphenol, in comparison to the standard rejected gallic acid, were found in the extract oil of Mart seeds by the methanol extraction.

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