Pancreatin from porcine pancreas 4 usp

Potassium iodate (KI), iodine (I₂), potassium hydroxide (KOH), sodium hydroxide (NaOH) and hydrochloric acid (HCl), were purchased from Merck (Darmstadt, Germany). Sodium chloride (NaCl) was purchased from BDH Chemicals (Poole, UK). Potassium chloride (KCl) was purchased from Fisher Scientific (Norcross, GA, USA). Sodium bicarbonate (NaHCO₃) was purchased from (Riedel-de Haën, Seelze, Germany). Heat stable α-amylase from Bacillus licheniformis (3000 U/mL), amyloglucosidase from Aspergillus niger (3300 U/mL), glucose oxidase peroxidase (GOPOD) kit and D-glucose standard (1 mg/mL) were purchased from Megazyme (Wicklow, Ireland). Alpha amylase from Aspergillus oryzae (30 U/mg) and pancreatin from porcine pancreas (4 × USP) were purchased from Sigma (St. Louis, MO, USA). Pepsin was purchased from PanReac AppliChem (Barcelona, Spain). Porcine bile extract was purchased from Santa Cruz Biotechnology (Dallas, TX, USA).

All chemicals and reagents used in the experiments were of per analysis and HPLC grade. Folin–Ciocalteu reagent, potassium chloride, sodium hydrogencarbonate, potassium hydrogenphosphate, magnesium chloride hexahydrate, sodium chloride, ammonium carbonate, sodium hydroxide, and petroleter were supplied from Kemika d.d. (Zagreb, Croatia). Anhydrous sodium carbonate and sodium nitrite were acquired from Gram-Mol d.o.o. (Zagreb, Croatia). Sodium molybdate (>98%) was supplied from abcr Gmbh (Karlsruhe, Germany). Methanol, acetonitrile, concentrated hydrochloric acid (37%, v/v), sodium hydroxide, and formic acid were purchased from Carlo Erba Reagents (Val de Reuil, France). Secondary analytical standards, i.e., echinacoside (>98%) and verbascoside (>98%), were obtained from Biosynth s.r.o. (Bratislava, Slovakia), whereas caffeine was supplied from Fluka (Taufkirschen, Germany). Theobromine (min. 99%), human salivary α–amylase XII-A (Enzyme Commission number: 3.2.1.1.; 1149 U mg⁻¹ protein), pepsin from porcine gastric mucosa (474 U mg⁻¹ protein), pancreatin from porcine pancreas (4×USP), and bile bovine salts (unfractionated) were provided from Sigma Aldrich (St. Louis, MO, USA).

Analytical grade chemicals were obtained from Carlo Erba (Milano, Italy). Bromelain was obtained from Nutraceutica (Bologna, Italy) (2400 GDU g⁻¹) and from Enzyme Development Corporation (New York, NY, USA). Pancreatin from porcine pancreas (4 USP) was purchased from Sigma-Aldrich (St. Louis, MI, USA).
Synthetic peptides used for Gel Permeation Chromatography (GPC) calibration were bought from Sigma-Aldrich (St. Louis, MI, USA) (i.e., bovine serum albumin (BSA), β-Lactoglobulin (β-Lg), α-lactalbumin (α-La), aprotinin, bacitracin, tetrapeptide (Leu-Trp-Met-Arg), Asp-Glu, Tyr).