Gochujang prepared using rice and wheat koji partially alleviates high-fat diet-induced obesity in rats

The aim of this study was to compare whether gochujang products prepared using giant embryo rice koji (rice gochujang, RG) and wheat koji (wheat gochujang, WG) have anti-obesity effects on rats fed a high-fat diet (HFD), who served as a model for obesity. The nutritional composition of RG and WG including proximate constituents, amino acid and fatty acid compositions were investigated. Consequently, the secondary fermented metabolites were analyzed in RG and WG by ultrahigh-performance liquid chromatography and mass spectrometry. Rats were fed a HFD containing 10% RG powder (HFD-RG) or 10% WG powder (HFD-WG) for 8 weeks. Body weight gain, weights of liver, epididymal, retroperitoneal, perirenal, and total white fat pads, and levels of serum triglyceride (TG), total cholesterol, low-density lipoprotein cholesterol, and leptin were lower in all gochujang groups than in the HFD group. Furthermore, RG and WG treatment decreased the hepatic TG content and lipid accumulation and significantly reduced the size of epididymal adipocytes. These effects are probably mediated through inhibition of hepatic fatty acid synthase, acetyl CoA carboxylase, malic enzyme, and adipose tissue lipoprotein lipase activities. The anti-obesity effect was slightly greater in the HFD-RG group than in the HFD-WG group. This effect may be attributed to secondary metabolites, such as capsaicin, genistein, daidzein, soyasaponin, and lysophosphatidylcholines, contained in gochujang prepared using giant embryo rice or wheat koji.

Dietary supplementation of germinated pigmented rice (Oryza sativa L.) lowers dyslipidemia risk in ovariectomized Sprague-Dawley rats

Background

In the recent years, cases of elderly women suffering from metabolic diseases such as dyslipidemias brought about by hormonal imbalance after menopause are continuously increasing. In this regard, a continuous and escalating demand to develop a more functional and highly nutritional food product as an adjunct supplement that can help alleviate these diseases is still being sought.

Objective

This study investigated the effects of germinated blackish-purple rice cultivars Keunnunjami, Superjami, and reddish-brown cultivar Superhongmi in the lipid metabolism of ovariectomized Sprague–Dawley rats.

Method

The animals were randomly divided into nine groups (n=5) and were supplemented with either non-germinated or germinated rice for 9 weeks. Then the plasma, liver, and fat samples were collected for the lipid metabolism effects analyses.

Results

Animals fed with germinated rice cultivars had improved lipid profile levels relative to the groups supplemented with non-germinated rice cultivars. The germinated rice groups, Keununjami and Superjami in particular, showed a low total cholesterol levels, high levels of high-density lipoproteins-cholesterol, high fecal lipid output, low hepatic lipid values, and low hepatic adipocyte accumulation. There was also an increase in the rate of lipolysis and decrease in lipogenesis based on the lipid-regulating enzyme activity profiles obtained for the groups that fed on germinated rice. Also, results revealed that pigmented rice cultivars had superior effects in improving the lipid metabolism relative to the non-pigmented normal brown rice variety.

Conclusion

Based on the results, this study suggests that germinated pigmented rice consumption can confer better lipid metabolism than ordinary white rice and constitutes as an effective functional food in alleviating the risk of having dyslipidemias like those suffering from menopausal co-morbidities.

Effect of fermented soybean product (Cheonggukjang) intake on metabolic parameters in mice fed a high-fat diet

As a nontargeted metabolomics approach, we investigated changes in the plasma metabolite levels in a mouse model of obesity induced by a high-fat diet and fermented soybean product diet. We analyzed the plasma samples by using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). In the present study, the animals were divided into four groups according to the diet type; normal fat diet control group (ND), high-fat diet control group (HD), high-fat diet plus 30% cooked soybean power (HD + S), and high-fat diet plus 30% 72-h fermented Cheonggukjang powder (HD + CGJ). To examine the changes in plasma metabolite levels because of high-fat diet feeding, total cholesterol and triglyceride levels were measured. Total cholesterol and triglyceride levels were lower in the HD + S and HD + CGJ groups than in the ND group. According to partial least-squares discriminant analysis (PLS-DA), major metabolites contributing to the discrimination between each group were assigned as lipid metabolites in plasma, e.g., lyso-phosphatidylcholines and phosphatidylcholines. Therefore, diets containing soy-based food products, which are rich sources of isoflavonoids, might be helpful for controlling the lipid metabolism under high-fat diet conditions.