Objective: To study the polyhydroxylated alkaloids of Polygonati Odorati Rhizoma with hypoglycemic effect. Method: The water extract of Polygonati Odorati Rhizoma was isolated and purified by various ion-exchange resins chromatography. The structures of isolated compounds were identified by using spectral analysis such as NMR and MS. The inhibitory activities on α-glucosidase and α-amylase of the isolated alkaloids were screened by PNPG and DNS methods. Result: Eight compounds were obtained from the water extract of Polygonati Odorati Rhizoma

including two polyhydroxy alkaloids

two acylamides

three amino acids and betaine. These isolates were identified as 1-deoxynojirimycin (1)

fagomine (2)

L-azetidine-2-carboxylic acid (3)

1

2 (S)-pyrrolidinedicarboxamide (4)

(2S)-citrullinamide (5)

serine (6)

-aminobutyric acid (7) and betaine (8). Compounds 1

2

4

5 and 8 were evaluated for their inhibitory activity on α-glucosidase and α-amylase. Compounds 1 and 2 showed potent inhibitory effect on α-glucosidase

with IC50of 0.098

0.272 mol·mL-1

respectively

whose activities were superior to the positive control Acarbose (IC50of 0.493 mol·mL-1). Furthermore

compound 1 showed inhibitory effect on α-amylase (IC50of 0.681 mol·mL-1)

but its inhibitory activity was inferior to Acarbose (IC50 of 0.035 mol·mL-1). Conclusion: Compounds 1-8 were isolated from this plant for the first time

and compounds 1 and 2 showed significant inhibitory effect on α-glucosidase. Therefore

polyhydroxylated alkaloids are the active components of Polygonati Odorati Rhizoma for exerting hypoglycemic effect.