On April 6, Beijing Technology and Business University and new vegetarian researchers Li Wenhui, Fu Xiaohang, Zhang Tianyu, Li He, Chen Tianpeng, and Liu Xinqi published a research paper on soybean protein lowering blood sugar in the JCR Q1 journal “Food&Function”.

Although extruded soy protein (ESPro) is currently used to produce plant-based meat, there are few studies involving its in vitro and in vivo hypoglycemic activity. In this study, the α-glucosidase inhibitory activity of ESPro with different extrusion parameters was compared, and it was found that ESPro1 (160°C, 30r/min) had the highest inhibitory activity. Then, ESPro1 was mock digested and ultrafiltered in vitro, yielding the ESPro1 digest (<1 kDa) with the highest inhibitory activity. Further separation by gel filtration chromatography yielded the ESPro1 F3 fraction with the highest inhibitory activity.

Finally, six peptides with α-glucosidase inhibitory activity were screened from ESPro1 F3 fraction and synthesized by solid-phase synthesis, among which LLLPPK showed the highest inhibitory activity (46.98±0.63%). During a four-week dietary intervention in mice with type 2 diabetes mellitus (T2DM), ESPro attenuated the tendency towards weight loss, lowered blood sugar, alleviated insulin resistance, and improved glucose tolerance, while ESPro1 reduced blood sugar levels by 22.33% at 28 days.

Research from: Isolation and identification of an α-glucosidase inhibitory peptide from extruded soybean protein and its hypoglycemic activity in T2DM mice

Furthermore, ESPro1 significantly increased serum high-density lipoprotein cholesterol (HDL-C) levels, decreased low-density lipoprotein cholesterol (LDL-C) levels, upregulated superoxide dismutase (SOD) and glutathione peroxidation GSH-Px activity, decreased malondialdehyde (MDA) content, decreased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, and relieved T2DM mice liver and Injury to the pancreas.

Overall, extruded soybean protein (160°C, 30r/min) showed excellent hypoglycemic effects both in vivo and in vitro, and may have beneficial effects in the treatment of T2DM.