The umami taste receptor is a heterodimer composed of two members of the T1R taste receptor family: T1R1 and T1R3. The homology models of the ligand binding domains of the human umami receptor have been constructed based on crystallographic structures of the taste receptor of the central nervous system. Furthermore, the molecular simulations of the ligand binding domain show that the likely conformation was that T1R1 protein exists in the closed conformation, and T1R3 in the open conformation in the heterodimer. The molecular docking study of T1R1 and T1R3 in complex with four peptides, including Lys-Gly-Asp-Glu-Ser-Leu-Leu-Ala, Ser-Glu-Glu, G1u-Ser, and Asp-Glu-Ser, displayed that the amino acid residue of SER146 and Glu277 in T1R3 may play great roles in the synergism of umami taste. This docking result further validated the robustness of the model. In the paper, binding of umami peptide and the T1R1/T1R3 receptor was first described and the interaction is the base of umami activity theory.

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Jinhua ham is popular in China because of its characteristic aroma. Unlike dry-cured western ham, it is cooked. The objective of this study was to evaluate the effect of three traditional cooking methods, steaming (B), boiling (C) and stewed ham Soup (S) on the volatiles in Jinhua ham (A). The volatiles were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) after extraction by Solid Phase Microextraction (SPME). The volatiles mainly consisted of alcohols, sulfur-containing compounds and cyclic compounds. Results from the Principal Components Analysis (PCA) showed A,

Nowadays, more and more people are suffering from insomnia with difficulty in initiating or maintaining sleep. Ganoderma lucidum (G. lucidum) and Ziziphi spinosae (Z. Spinosae) are conventional herbal drugs in traditional Chinese medicine and they have been used lonely for the treatment of insomnia. In the present study, G. lucidum and Z. spinosae were combined and the active fractions were extracted to make the capsule. Furthermore, their effect on improving sleep in mice was investigated. The functional compositions of the capsule were polysaccharide, total flavone, spinosin and triterpenoid, with the content being 12.08, 1.35, 0.67 and 1.50 g/100 g, respectively. The effect of the capsule on improving sleep in mice was studied. Results showed no effects on the sleep induced directly in mice assessed with the loss-of-righting reflex even at the high dose of 450, 1350 mg/kg/day. However, the capsule significantly decreased sleep latency and increased sleeping time and prolonged sleeping time induced by pentobarbital sodium at high doses. In conclusion, the capsule of G. lucidum and Z. spinozae combined had the function of improving sleep.