Sodium deuterium oxide naod

Absolute ethanol (EtOH) for the extraction of plant samples was purchased from HmBg Chemicals Inc. (Germany). For the α-glucosidase inhibitory assay, quercetin, glycine, 4-nitrophenyl-α-D-glucopyranoside and α-glucosidase from Saccharomyces cerevisiae were purchased from Sigma Aldrich (St. Louis, USA). Folin-Ciocalteu’s phenol reagent, gallic acid, and sodium carbonate (Na₂CO₃) were also supplied by Sigma Aldrich. For NMR measurements, deuterated methanol (CD₃OD), non-deuterated KH₂PO₄, sodium deuterium oxide (NaOD), trimethylsilyl propionic acid-d4 sodium salt (TSP) and deuterium oxide (D₂O) were purchased from Merck (Darmstadt, Germany). For liquid chromatography mass spectrometry (LC-MS) analysis, HPLC grade methanol, acetonitrile, acetic acid and hydrochloric acid were purchased from Merck (Darmstadt, Germany). Liquid nitrogen was supplied by MOX Company (Petaling Jaya, Malaysia).

The chemicals 2,4,6,-tripyridyl-s-triazine (TPTZ), 6-Hydroxy-2,5,7,8-tetra-methylchroman-2-carboxylic acid (Trolox), 1,1-diphenyl-2-picrylhydrazyl (DPPH), lanthanum(III) chloride heptahydrate, CuCl₂·2H₂O, 2,9-dimethyl-1,10-phenanthroline (neocuproine), 2,2-azino-bis(3-ethylbenzothiazloine-6-sulphonic acid) (ABTS) radical cation, ferric chloride, caffeic acid, quercetin, tannic acid, catechin, human serum albumin (HSA), fibrinogen, globulin, phosphate buffer and Folin-Ciocalteu reagent (FCR) were purchased from Sigma (St. Louis, MO, USA) and Fluka Chemie Gm bH, Buchs, Switzerland. All NMR chemicals, including 3-trimethylsilylpropanoic acid (TSP), potassium phosphate monobasic (KH₂PO₄), methanol-d4 (CD₃OD, 99.8%), sodium deuterium oxide (NaOD), and deuterium oxide (D₂O, 99.9%), were purchased from Merck (Darmstadt, Germany).

The chemicals 6-Hydroxy-2,5,7,8-tetra-methylchro man-2-carboxylic acid (Trolox), catechin, tannic acid, gallic acid, human serum albumin (Alb), fibrinogen (Fng), globulin (Glo), 2, 4, 6-tripyridyl-s-triazine (TPTZ) aluminium chloride, potassium peroxydisulfate and 2, 2′-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS), chloride dihydrate, sodium hydroxide, hydrochloric acid (37% w/w), phosphate buffer and Folin–Ciocalteu reagent (FCR) were purchased from Sigma (St. Louis, MO, USA) and Fluka Chemie GmbH (Buchs, Switzerland). Standard phenolics were dissolved in methanol (1 mg/mL). All reagents and chemicals were of analytical grade.
All NMR chemicals, including 3-trimethylsilylpropanoic acid (TSP), potassium phosphate monobasic (KH₂PO₄), methanol-d4 (CD₃OD, 99.8%), sodium deuterium oxide (NaOD) and deuterium oxide (D₂O, 99.9%), were purchased from Merck (Darmstadt, Germany).