Abstract
The present research aimed to further identify the fine structure, morphology, and thermal behaviors of a gal-actoglucan BHP-2 derived from Lanzhou lily bulbs through partial acid hydrolysis, methylation, 2D NMR (1H-1H COSY, HSQC, and HMBC), scanning electron microscopy (SEM) and thermogravimetric-differential thermal analysis (TG-DTA). Additionally, the study assessed the potential in vitro hypoglycemic effect of BHP -2 by examining its inhibitory effect on alpha-glucosidase and alpha-amylase. The results indicated that the main back-bone composition of BHP-2 consisted of -> 4)-alpha-D-Glcp-(1 ->, -> 3)-beta-D-Glcp-(1 -> and -> 6)-beta-D-Galp-(1 ->, while the side chain composition predominantly featured -> 4)-alpha-D-Glcp-(1 ->, -> 3,5)-alpha-L-Araf-(1 -> and -> 3)-beta-D-Galp- (1 ->, attached to the C-2 and/or C-3 positions of -> 4)-alpha-D-Glcp-(1 ->. Terminal residues consisted of alpha-D-Glcp-(1 -> and beta-L-Araf-(1 ->. BHP-2 exhibited excellent thermal stability, with a microscopic surface characterized by tightly packed sheets and numerous spiral depressions, which might contribute to its remarkable in vitro hy-poglycemic effect. BHP-2 showed competitive inhibition of alpha-amylase and mixed non-competitive inhibition of alpha-glucosidase, with respective IC50 values of 0.31 and 0.18 mg/mL, closely resembling to those of acarbose (0.27 and 0.12 mg/mL). These findings suggested that BHP-2 had potential as an additive for glycemic intervention.
Keywords Plus：CHEMICAL-CHARACTERIZATION，ALPHA-GLUCOSIDASE，POLYSACCHARIDES，ANTIOXIDANT，INHIBITION，EXTRACTION，AMYLASE
Published in INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES，Volume254，10.1016/j.ijbiomac.2023.127774；JAN 2024