α glucosidase ec3.2.1.20

α-glucosidase (EC3.2.1.20) was obtained from Sigma Aldrich, and acarbose was obtained from Bayer, Pakistan. An ELISA Micro Plate Reader (Emax) from Molecular Devices and isolated compounds 1–5 from D. cycadina were used.

All starting materials and reagents were purchased from commercial suppliers. α-glucosidase (EC 3.2.1.20) was purchased from Sigma-Aldrich. TLC was performed on Silica gel F-254. Melting points were measured on a microscopic melting point apparatus. The ¹H NMR and ¹³C NMR were measured (DMSO solution) with Bruker spectrometer (500 MHz ¹H, 125 MHz ¹³C). HRMS was performed on AB SCIEX Triple TOF 5600+ with electron spray ionisation (ESI) as the ion source.

¹H and ¹³C NMR spectra were recorded on a Bruker AM500
spectrometer (Bruker, Karlsruhe, Germany). Melting points were measured on a Thomas
Scientific Capillary Melting Point Apparatus. MS and HR-MS were obtained on a JEOL JMS-700
mass spectrometer (JEOL, Tokyo, Japan). IR spectra were recorded on Varian 640-IR (Varian,
Inc., USA). Optical rotation was measured on a Perkin-Elmer 343 polarimeter (Perkin-Elmer,
Bridgeport, USA). Recycled HPLC and MPLC were conducted on Forte/R 100 (YMC Co., Ltd.,
Kyoto, Japan) using Triart C18 (S-5 µm, 12 nm and S-10 µm, 12 nm, YMC, Japan). Analytical
grade methanol, acetonitrile, and acetic acid for HPLC were purchased from Fisher (Fisher
Scientific Korea Ltd.). UV spectra and enzymatic assays were carried out on a SpectraMax
M3 Multi-Mode Microplate Reader (Molecular device, USA). α-Glucosidase (EC3.2.1.20) was
purchased from Sigma Aldrich St. Louis, USA. All chemicals were of analytical grade.