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.