Lysimachia vulgaris L. aerial part and root methanol extracts as potential α-amylase and α-glucosidase inhibitors

Abstract

Anti-diabetic properties of many plants are documented so far, predominantly due to some polyphenolic compounds that can inhibit enzymes involved in the digestion of carbohydrates and significantly reduce the postprandial increase of blood glucose [1]. Lysimachia vulgaris L., commonly known as yellow loosestrife, is a medicinal plant traditionally used to treat ulcers, fever, inflammation, and diarrhea. Its antifungal, antibacterial, anticancer, and antioxidant properties have also been verified. The aim of this investigation was to evaluate the possible inhibition activity of α-amylase and α-glucosidase using aerial part (LVA) and root (LVR) methanolic extracts of L. vulgaris. The results showed that LVR has a significantly higher ability to inhibit both enzymes (IC50 = 146.34 µg/mL for α-amylase: IC50 < 31.25 µg/mL for α-glucosidase) in comparison with LVA extract. Furthermore, when compared to acarbose (IC50 = 340.13 µg/mL), a drug used as medicine for many years to treat diabetes mellitus type 2, LVR had approximately ten times higher inhibition activity of α-glucosidase. However, acarbose was significantly more effective in the inhibition of α-amylase compared with the tested extracts. The obtained results are in correlation with our previous research which confirmed that LVR is richer in the phenolic compounds content in comparison with LVA. Due to the strong inhibition potential of LVR extract, further research may be on the identification and quantification of compounds in extracts responsible for the inhibition of these enzymes, as well as in vivo animal experiments for possible treatment of diabetes mellitus type 2 using L. vulgaris.