Dual high-resolution inhibition profiling and HPLC-HRMS-SPE-NMR analysis for identification of alpha-glucosidase and radical scavenging inhibitors in Solanum americanum Mill

作者：Silva Eder L; Almeida Lafeta Rita C; Borges Ricardo M; Staerk Dan

来源：Fitoterapia, 2017, 118: 42-48.

DOI：10.1016/j.fitote.2017.02.002

• Type 2 diabetes
• HPLC-HRMS-SPE-NMR
• High-resolution bioactivity profiling
• alpha-Glucosidase
• Antioxidants
• Solanum americanum

Solanum americanum is one of the most prominent species used to treat type 2 diabetes in Guatemala. In our ongoing efforts to find antidiabetic and antioxidative compounds from natural sources, an ethyl acetate extract of this medicinal herb was investigated using dual high-resolution alpha-glucosidase/radical scavenging inhibition profiling. The high-resolution biochromatograms obtained by this technique were used to target subsequent structural elucidation by HPLC-HRMS-SPE-NMR analysis towards the bioactive constituents. This led to identification of 4-hydroxybenzoic add (1) and 3-indolecarboxylic acid (6) associated with radical scavenging activity, and the amide alkaloids N-trans-p-coumaroyloctopamine (3), N-trans-p-feruloyloctopamine (4), N-trans-pcoumaroyltyramine (8) and N-trans-p-feruloyltyramine (9) correlated with a-glucosidase inhibitory activity as well as radical scavenging activity. Further analysis revealed a new lactone, methyl 5-ethyl-4-hydroxy-5-methyl-2-oxotetrahydro-2H-pyran-4-carboxylate (7) and a new steroid with a rare F ring (11). Corchorifatty acid B (12) was reported for the first time in the Solanaceae family. Their structures were elucidated by extensive use of 1D and 2D NMR spectroscopy as well as HRMS analysis.

• 出版日期2017-4