The aim of present study is to investigate the hypocholesterolemic effects of the oat components other than the β-glucan in rats fed with a hypercholesterolemic diet. Four-week-old male Wister rats were divided into 6 groups of 7 rats each with similar mean body weights and serum cholesterol concentrations. Rats were fed with the experimental diets containing 10% oats flour for 30 days. Food intake was recorded and monitored everyday to ensure the similar contents of protein, starch, lipid and cellulose in all groups. The lipids levels in serum, liver, and faeces were determined. The plasma total cholesterol concentrations in different oat groups were significantly reduced compared with the control group, and the effects were different among oat groups. The decrease extent of plasma total cholesterol and low-density lipoprotein-cholesterol concentrations increased with the increase of the proteins and lipids contents. Moreover, liver total cholesterol and cholesterol ester contents were markedly decreased. The fecal bile acids concentrations in the oat groups were significantly increased. Oat proteins had lower Lysine/Arginin (0.59 ~ 0.66) and Methionin/Glycine (0.27 ~ 0.35) ratio than casein (Lysine/Arginin, 2.33; Methionin/Glycine, 1.51). Oat lipids contained higher contents of total Vitamin E and plant sterols than that in soybean oil. These results indicated that dietary oat improved hypercholesterolemia by increasing the excretions of fecal bile acids, and this improvement was not only related to β-glucan, but also attributed to the lipids and proteins. Oat proteins decreased serum total cholesterol and low-density lipoprotein-cholesterol contents due to their low Lysine/Arginin and Methionin/Glycine ratio. The co-existence of oleic acid, linoleic, vitamin E, or plant sterols accounted for the hypocholesterolemic properties of oat lipids.
As an essential trace element in the human body, selenium (Se) has various physiological activities, such as antioxidant and anticancer activity. Selenium-enriched proteins/peptides (SePs/SePPs) are the primary forms of Se in plants and animals, and they are the vital carriers of its physiological activities. On the basis of current research, this review systematically describes the extraction methods (aqueous, alkaline, enzymatic, auxiliary, etc.) and detection methods (HPLC–MS/MS, GC–ICP-MS, etc.) for SePs/SePPs in plants. Their bioavailability and bioactivity, and the effect of processing are also included. Our review provides a comprehensive understanding and theoretical guidance for the utilization of selenium-enriched proteins/peptides.
The structural and functional properties of physical modified rice flour, including ultrasound treated rice flour (US), microwave treated rice flour (MW) and hydrothermal treated rice flour (HT) were investigated with wet-milled rice flour (WF) used as a positive control. The results showed the presence of small dents and pores on the rice flour granules of US and MW while more fragments and cracks were showed in HT. XRD and FTIR revealed that moderate ultrasonic treatment promoted the orderly arrangement of starch while hydrothermal treatment destroyed the crystalline structure of rice flour. In addition, the significant decrease of gelatinization enthalpy and the narrowing gelatinization temperature were observed in US. Compared to that of SF, adding physical modified rice flour led to a batter with higher viscoelasticity and lower tan δ. However, the batter added HT exhibited highest G′ and G″ values and lowest tan δ, which led to a harder texture of bread. Texture analysis demonstrated that physical modified rice flour (except HT) reduced the hardness, cohesion, and gumminess of rice bread. Especially, the specific volume of bread with US increased by 15.6% and the hardness decreased by 17.6%. This study suggested that ultrasound treatment of rice flour could improve texture properties and appearance of rice bread.