Dang Kim Thu, Le Thi Thu Huong, Tran Trong Nghia, Bui Thanh Tung

Main Article Content


Type 2 diabetes is a fairly common chronic disease. α-glucosidase and protein tyrosine phosphatase, as enzymes, play an important role in type 2 diabetes. This study evaluates the inhibitory effect of the two enzymes in vitro of ethanol extract and fractions of Vietnam Psidium guajava’s leaves. The leaves were collected, dried and extracted with 96% ethanol and successively fractionated with n-hexane, ethyl acetate and butanol solvents. The results show that the EtOH extract, n-nexan, EtOAc and BuOH fractions had high α-glucosidase inhibitory effect with IC50 values ​​of 2.20; 2.53; 2.24 and 2.16 µg/mL, respectively. In addition, EtOAc and BuOH fractions also show strong inhibitory PTP1B effect with IC50 at 120.22 mg/mL and 97.72 mg/mL, respectively. The study results show that Psidium guajava leaves are a potential source of material to inhibit α-glucosidase and PTP1B in the treatment of diabetes.


Psidium guajava, α-glucosidase, protein tyrosine phosphatase 1B, diabetes, extraction.


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