Yeast α glucosidase enzyme

Optical rotations were obtained with a Perkin-Elmer 341 polarimeter (Boston, MA, USA). UV spectra were measured on a Milton Roy Spectronic 300 Array spectrophotometer, and IR was recorded on a Perkin-Elmer FT-IR 1760x spectrophotometer (Boston, MA, USA). High-resolution electrospray ionization mass spectra (HR-ESI-MS) were recorded with a Bruker micro TOF mass spectrometer (Billerica, MA, USA). NMR spectra were obtained with a Bruker Avance DPX-300 FT-NMR spectrometer (Billerica, MA, USA). Vacuum liquid chromatography (VLC) and column chromatography (CC) were performed on silica gel 60 (Merck, 70–230 µm, Darmstadt, Germany), silica gel 60 (Merck, 230–400 nm) or Sephadex LH-20 (Pharmacia, Piscataway, NJ, USA). Yeast α-glucosidase enzyme, p-nitrophenol-α-d-glucopyranoside, pancreatic lipase, and 4-methylumbelliferyl oleate were purchased from Sigma Chemical, Inc. (St. Louis, MO, USA), and acarbose from Fluka Chemical (Buchs, Switzerland).

Optical rotations were determined with a PerkinElmer Polarimeter 341 (Boston, MA, USA). UV spectra were recorded on a Milton Roy Spectronic 3000 Array spectrophotometer (Rochester, Monroe, NY, USA). IR spectra were obtained with a PerkinElmer FT-IR 1760X spectrophotometer (Boston, MA, USA). Mass spectra were measured using a Bruker MicroTOF mass spectrometer (ESI-MS) (Billerica, MA, USA). NMR spectra were recorded on a Bruker Avance DPX-300FT NMR spectrometer or a Bruker Avance III HD 500 NMR spectrometer (Billerica, MA, USA). Yeast α-glucosidase enzyme and p-nitrophenol-α-d-glucopyranoside were obtained from Sigma Chemical, Inc. (St. Louis, MO, USA), and acarbose was purchased from Fluka Chemical (Buchs, Switzerland). Microtiter plate readings were carried out with a CLARIOstar apparatus (BMGLABTECH, Ortenberg, Germany).

Folin-Ciocalteu, gallic acid, ascorbic acids, quercetin, butyl hydroxyl toluene (BHT), 1,1-diphenyl-2-picrylhydrazyl (DPPH), bovine serum albumin (BSA), aminoguanidine, captopril, pancreatic α-amylase, yeast α-glucosidase enzyme, p-nitrophenyl-α-D-glucopyranoside, acarbose, furanacroloyl-Phe-Glu-Glu (FAPGG) and trichloroacetic acid (TCA) were purchased from Sigma-Aldrich (Sydney, Australia). All other chemicals used were of analytical or HPLC grade.