α amylase from aspergillus

Folin–Ciocalteu (FCR), sodium carbonate (Na₂CO₃), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ABTS, 2,6-di-tert-butyl-4-methylphenol (BHT), butylated hydroxyanisole (BHA), α-amylase from Aspergillus oryzae Green Alternative powder, ≥150 units/mg protein (biuret), gallic acid, quercetin, and AlCl₃ were purchased from Sigma (Sigma-Aldrich, Taufkirchen, Germany). All the organic solvents and other chemicals used in the present study were of analytical grade and were obtained from Sigma-Aldrich (Sigma-Aldrich, Germany).

KRG extracts (15 brix) from 6-year-old roots of Panax ginseng Meyer were purchased from the Korea Ginseng Corporation. Three carbohydrate-digesting enzymes, pectinesterase from orange peel, amyloglucosidase from Aspergillus niger, and α-amylase from Aspergillus orizae, were purchased from Sigma-Aldrich. Dithiothreitol (DTT), ammonium bicarbonate (NH₄HCO₃), formic acid (FA), urea, ammonium formate, iodoacetamide (IAA), and trifluoroacetic acid (TFA) were also obtained from Sigma-Aldrich. Polygalacturonase from Aspergillus aculeatus was acquired from Megazyme. Water and acetonitrile (ACN) with a high-performance liquid chromatography (HPLC) grade were obtained from JT Baker (Phillipsburg, NJ, USA), and lyophilized trypsin was purchased from Promega (Madison, WI, USA). In accordance with a previous study [15 ], NFP was extracted from the KRG concentrate using ethanol precipitation, enzymatic hydrolysis, and size-exclusion chromatography. The analysis of free sugars was carried out using a modified version of the method published by Joo et al [16 ]. The extraction of 0.1 g NFP with 10 mL of distilled water produced six free sugars: galactose, fructose, glucose, maltose, lactose, and sucrose. The NFP has 139.6 ± 2.8 mg/g galacturonic acid, 74.7 ± 4.6 mg/g galactose, and 63.4 ± 4.1 mg/g arabinose, according to the acidic polysaccharide components analysis.