Comparison of Anti-Obesity Effect between Two Types of Syrup Containing Rare Sugars in Wistar Rats.

D-Allulose-containing rare sugar sweeteners have been categorized into two types, rare sugar syrup (RSS), consisting of 4 rare monosaccharides, and modified glucose syrup (MGS), rich in D-allulose, which was previously referred to D-psicose. The anti-obesity effect of RSS and D-allulose has been already clarified, but that of rare monosaccharides other than D-allulose in RSS has not yet been well understood. Here, we investigated and compared the anti-obesity effect of RSS and MGS in rats. Male Wistar rats were divided into 4 dietary groups: a high-sucrose control diet group (S), a high-fructose corn syrup diet group (HFCS), an RSS diet group (RSS), and an MGS diet group (MGS). RSS significantly suppressed abdominal adipose tissue weight and total body fat accumulation in comparison to sucrose. On the other hand, MGS reduced body weight gain, but not abdominal fat accumulation, relative to sucrose. The weight of the liver and kidneys was significantly higher in the RSS and MGS groups than in the S and HFCS groups, but serum biochemical parameters and hepatic lipids contents were not significantly different among the groups. The present study shows that two types of D-allulose-containing rare sugar sweeteners can suppress body fat accumulation or weight gain in a different manner and that RSS could be used as more effective sweeteners in place of sucrose and HFCS to maintain healthy body weight.

Egg White Hydrolysate Can Be a Low-Allergenic Food Material to Suppress Ectopic Fat Accumulation in Rats Fed an Equicaloric Diet.

Egg white (EW) is known as a nutritional protein but can induce allergic reactions in humans. We investigated the dietary effects of EW and its hydrolysate (EWH), which contains less allergen, on body fat accumulation in Wistar rats fed an equicaloric high-fat and high-sucrose diet for 8 wk (Exp A). The pair-feeding of EW and equicaloric-feeding of EWH increased fecal fat excretion and suppressed lipid accumulation in the liver and muscles but not in the abdominal adipose tissues, carcass, or total body. Dietary EWH also suppressed the serum glucose level and alkaline phosphatase activity. Further, we showed a higher dispersibility of EW and EWH in physicochemical assay (Exp B). Next, we investigated the suppressive effects of a single administration of EW and EWH on lipid-induced hypertriglyceridemia and small intestinal meal transit in ddY mice (Exp C). However, a single administration of EW or EWH did not suppress the lipid-induced hypertriglyceridemia nor did it delay the rate of small intestinal transit. These findings indicated that dietary EW and EWH reduce hepatic and muscular (ectopic) fat accumulation mainly by suppressing fat absorption and supplying fat to the liver and muscles. Therefore, the low-allergenic EWH can be effective for the prevention of high-fat-diet-induced obesity.