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The purpose of this study is to investigate the inhibitory effect of oryzanol on the degradation of tocopherol during heating of rice bran oil at 110 and 170 °C and the oxidation kinetics of rice bran oil. Results demonstrate the degradation of oryzanol and tocopherol in rice bran oils follow the first‐order kinetic models. The higher concentration of oryzanol has no inhibitory effect on the degradation of tocopherol when the concentration of tocopherol in rice bran oil is 500 mg kg−1. However, when the concentrations of tocopherol reach 1500 and 2000 mg kg−1, higher oryzanol concentration make the inhibitory effects on the degradation of tocopherol more pronounced. Compared with rice bran oils containing lower levels of tocopherol and oryzanol, rice bran oils containing higher levels of tocopherol and oryzanol have higher activation energy (Ea), activation enthalpy (ΔH), and activation entropy (ΔS) and a larger temperature acceleration factor (Q10), which indicate that higher levels of oryzanol and tocopherol promote the thermal oxidation of rice bran oil. Therefore, in the compound application of tocopherol and oryzanol in rice bran oil, the influence of its content on the thermal oxidation of oil should be fully considered. Practical Application: This study may be useful for the grain and oil industry because studies on the degradation kinetics of oryzanol and tocopherol during heating of rice bran oil and oxidation kinetics of rice bran oil are still lacking in the literature. The results of this study is valuable for predicting and evaluating the oxidation process and nutritional properties of rice bran oils under various thermal oxidation conditions.

Introduction:The purpose of the present study was to reveal the potential positive effect of the Ta-ermi extracts on oxidative stress and streptozotocin (STZ)-diabetic mice and rats treated with Ta-ermi water-and alcohol-extracts. Methods: The study was carried out using three experimental model: 1) in vitro experiments whereby Ta-ermi extracts were incubated with free radical generators such as 2,2-diphenyl-1picryl-hydrazyl-hydrate (DPPH) and 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) to evaluate Ta-ermi's antioxidant effects; 2) testing the hypoglycemic effects of Ta-ermi extracts in streptozotocin (STZ)-induced diabetic mice; and 3) testing the beneficial effects of Ta-ermi extracts on mitochondrial complex I function using STZ-diabetic rats. Results: In vitro antioxidant experiments showed that both of the extracts could scavenge free radicals and exhibited inhibitory effects on glucosidase and aldose reductase with differential effects between water extract and alcohol extract. In the STZ mouse diabetic model, both the water-and alcohol-extracts attenuated body weight decrease, decreased blood glucose levels in a concentration-dependent manner, improved insulin sensitivity, and increased oral glucose tolerance ability. In the STZ-diabetic rat model, both the waterand alcohol-extracts were found to be able to lower blood glucose levels in the diabetic animals with no effects on body weight changes. Moreover, in the STZ-diabetic rats, both the water-and alcohol-extracts of Ta-ermi could inhibit the increase of mitochondrial NADH/ ubiquinone oxidoreductase (complex I) activity in the pancreas and enhanced complex I activity in the liver but showed no effect on lung or kidney mitochondrial complex I. Discussion: The present study points to the potential medicinal value of Ta-ermi's water and alcohol extracts in lowering blood glucose and decreasing diabetic oxidative stress. One limitation of our study is that the compound or compounds that actually have this beneficial effect in the extracts remain unknown at this time. Therefore, the future studies should be focused on the identification of the components in the extracts that exhibit anti-oxidative and hypoglycemic effects. Conclusion: Taken together, our studies using different experimental paradigms indicate that Ta-ermi extracts possess antioxidant and anti-diabetic properties and may be employed as functional food ingredients for the remission of diabetes.

The objective of this study was to improve the content of docosahexaenoic acid (DHA) and obtain the blended oils used for different cooking methods (steaming, boiling, and stir-frying) by blending 0%-15% DHA algal oil into soybean oil. It was shown that the addition of DHA algal oil increased saturated fatty acid (SFA) (1.57%) but decreased monounsaturated fatty acid (MUFA) (0.76%) and polyunsaturated fatty acid (PUFA) (0.68%). Various cooking methods significantly changed the fatty acid (FA) compositions. Steaming is a more effective way to prevent DHA loss and the production of trans-fatty acid than boiling and stir-frying. Besides, a positive result from free fatty acid (FFA) and peroxide value also demonstrated that steaming was a better way to protect oils. Overall, the soybean oil blended with 3% DHA algal oil with better oxidative stability and could be recommended for daily application by steaming. K E Y W O R D Sblend oil, cooking methods, docosahexaenoic acid algal oil, fatty acid profiles, oxidative stability, soybean oil