Chembio3d ultra

The ChemBio3D Ultra (CambridgeSoft Corporation, Massachusetts, United States) was used to draw the 2D structures of the main phenolic compounds in BW samples. It is worth noting that little information was available regarding the structure of α-glucosidase from Saccharomyces cerevisiae. Hence, its homologous structure (isomaltase, PDB ID: 3A4A) obtained from RCSB PDB was usually applied to conduct the docking test [27 (link),28 (link)]. The Surflex-Dock Geom (SFXC) mode was used to perform docking analysis using SYBYL-X 2.0 software (Tripos, Inc., St. Louis, MO, USA). A docking score file was generated, and a C-score ≥ 4 was considered as a credible result. Several parameters including four score functions (T-score, PMF-score, D-score, and CHEM-score), hydrogen bond distances, and amino acid binding sites were used to explain the active inhibitory mechanisms of the main phenolics against α-glucosidase [29 (link)].

The spin densities, EPR hyperfine and quadrupole parameters of the spin probes were calculated with the ORCA software package [22 ]. First, the geometry of the probe molecules was optimized by a MM2 forcefield calculation in the program ChemBio3D Ultra (Cambridge Soft, Cambridge, UK). A second geometry optimization was performed by DFT in ORCA using the B3LYP functional and a split valence basis set (SVP). The spin density distribution and EPR parameters were calculated using the B3LYP functional and EPR II the basis set [23 ].