Flavonoids have always been considered as the chemical basis for the hypoglycemic effect of mulberry leaves. In the course of our search for hypoglycemic effect agents from natural sources, a systematic study was launched to explore prenylated flavonoids from mulberry leaves. Herein, chemical investigation led to the isolation of 10 characteristic prenylated flavonoids, including two new compounds (1 and 3). Their structures were elucidated based on spectroscopic data. All compounds exhibited good α-glucosidase inhibitory activity in vitro, among which compound 2 had the best activity (IC 50 = 2.6 μM), better than acarbose (IC 50 = 19.6 μM). Additional in vivo tests have further demonstrated compound that compound 2 has a good ability to reduce postprandial blood glucose. Then, multi-spectroscopic methods and molecular simulation studies were used to study the inhibition mechanism. The results showed that compound 2 was a mixed inhibition of α-glucosidase and the binding process was spontaneous, with van der Waals forces as the main driving force, followed by hydrogen bonding and electrostatic forces. The above studies enriched the chemical basis of mulberry leaves, and the application of computational chemistry also provided a reference for future research on such structures.

With the continuous improvement of people's living standards, food intake, bioactivity, and bioavailability have mainly concerned people. Therefore, the digestion and absorption of this kind of food have attracted people's attention. Some food has very high nutritional, medicinal, and medical value. However, because of its low conversion rate and utilization rate, the human body digests and absorbs less material, so the use of human value will be significantly reduced. Therefore, simulation and testing of digestion and absorption in vitro may be significant for dietary intake of bioactive substances. This paper reviews the organs and pathways of simulated food digestion and absorption in vitro and specific processing methods. In an in the vitro simulation system, the role of the human digestive system and absorption system in food digestion and absorption is described, and the performance of various simulation models, exceptionally dynamic in vitro models, is compared. Widespread use and refinement of these models will expand our understanding of the complex interplay of food substrates and digestive and absorptive systems. Therefore, it will be possible to design food with better bioavailability, more benefits to human health, and more targeted delivery, which is also in line with the development trend of food in the future.

With the rapid development of food industry, people pay more and more attention to the health benefits of food‐active molecules. The active function of food molecules depends on the chemical structure. So how to determine the chemical composition of food becomes very important. Based on this, this paper mainly expounds the structural analysis methods and specific processes of food chemical components, as well as the difficulties encountered in the determination of structure, and summarizes the latest research trends of food structural analysis. The purpose is to let more scholars understand the structure analysis process of the chemical substance basis of food, and provide a reference for the healthy development of food.

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This paper introduces the in vitro test method of hypoglycemic components in food-grade natural products. The specific steps and results of the experimental methods were introduced in detail, including enzyme inhibition test, inhibition kinetics test, multispectral analysis, cell screening model test, molecular docking, and molecular dynamics test. Through the above series of tests, we can judge whether the components in natural products have a lowering effect on blood glucose and analyze the mechanism of action.