The global prevalence of obesity has nearly tripled in the past 40 years and continues to rise at an alarming rate. High fat and high carbohydrate diets can cause gut microbiota disturbance and impairment of intestinal barrier function in obese individuals. Dysbiosis of the gut microbiota and its metabolites crossing the intestinal barrier lead to insulin resistance, imbalance in energy metabolism, reduced fat browning capacity and increased levels of inflammatory factors, which in turn induce chronic diseases such as diabetes, hypertension and cardiovascular diseases. In this paper, the molecular mechanism of obesity mediated by the gut microbiota is systematically elucidated. Based on this, we propose that the intestinal microecology can be regulated by supplementing probiotics and prebiotics or by changing lifestyle and dietary pattern, which in turn will help to prevent and control obesity.

In this study, ion exchange chromatography was employed to prepare high-purity α-lactalbumin from whey protein powder obtained from raw cow’s milk by sequential membrane separation and spray drying. The results showed that α-lactalbumin constituted 21.04% of the true protein in the permeate obtained using a 50-nm pore-sized ceramic membrane with three-fold concentration, one cycle of microfiltration and two cycles of washing, which was higher than that obtained using a 100-nm pore-sized ceramic membrane (15.84%). The permeate was spray dried and separated by ion exchange chromatography. Good chromatographic separation of α-lactalbumin and β-lactoglobulin was achieved with increasing NaCl concentration from 0 to 0.5 mol/L at up to 10 column volumes, and 98.18% pure α-lactalbumin and 97.82% pure β-lactoglobulin were obtained. The results of this study provide support for the industrial preparation of high-purity α-lactalbumin.