Dual High-resolution Inhibition Profiling and HPLC-HRMS-SPE-NMR Analysis for Identification of α-Glucosidase and Radical Scavenging Inhibitors in Solanum americanum Mill.
Solanum americanum is one of the most prominent species used to treat type 2 diabetes (T2D) in Central America [1]. Despite its use in folk medicine, no study has been done to identify bioactive constituents. Therefore, we perform the first antidiabetic and antioxidant investigation of S. americanum.
In this study, an ethyl acetate extract of S americanum was subjected to high-resolution radical scavenging and α-glucosidase inhibition profiling with the aim of targeting subsequent HPLC-HRMS-SPE-NMR analysis towards bioactive compounds.
This led to identification of two acids (1 and 6) associated with radical scavenging activity, and four amide alkaloids (3, 4, 8, 9) correlated with α-glucosidase inhibitory activity as well as radical scavenging activity. Further analysis revealed a new lactone (7) and a new steroid with a rare F ring (11). Their structures were elucidated by extensive use of 1D and 2D NMR spectroscopy as well as HRMS analysis.
References
[1] E. C. Cruz, A. Andrade-Cetto, Ethnopharmacological field study of the plants used to treat type 2 diabetes among the Cakchiquels in Guatemala, J. Ethnopharmacol. 159 (2015) 238-244.