S allyl l cysteine

α-Amylase enzymes from human saliva (937 units/mg protein), pepsin (500 units/mg protein), pancreatin from porcine pancreas (4 × UPS), bile salts, and calcium chloride were purchased from Sigma-Aldrich (Madrid, Spain). HCl was obtained from Merck (Darmstadt, Germany), and NaOH was acquired from Fisher Scientific (Madrid, Spain). Sodium bicarbonate and ammonium carbonate were purchased from Sigma-Aldrich (Madrid, Spain), sodium chloride and magnesium chloride hexahydrate were purchased from Fisher Scientific (Madrid, Spain), and potassium dihydrogen phosphate was obtained from VWR International Eurolab (Barcelona, Spain). Reference flavonoid compounds including isorhamnetin, luteolin, quercetin, quercetin-3-O-glucoside alliin and s-allyl-L-cysteine (SAC) together with formic acid were acquired from Sigma-Aldrich (Madrid, Spain). Ammonium formate, ammonium acetate, and ethanol were obtained from Sigma-Aldrich. Acetonitrile (LC-MS grade) and methanol (LC-MS grade) were obtained from Panreac (Barcelona, Spain).

The reference standard compounds including S-allyl-L-cysteine sulfoxide (alliin) and S-allyl-L-cysteine (SAC) were purchased from Sigma-Aldrich (Madrid, Spain). Ammonium acetate, ammonium formate and ethanol were obtained from Sigma-Aldrich. Acetonitrile, methanol and water were of LC-MS grade.

The levels of S‐allyl‐L‐cysteine were analyzed by the Korean Food Research Institute (Chonbuk). Briefly, the extracts were filtered through a 0.45‐m syringe filter (Merck KGaA) and the filtrate was analyzed using S‐allyl‐L‐cysteine (≥98%; Sigma‐Aldrich) as a standard. A HPLC‐UVD system (Shimadzu, Shimadzu Corporation) fixed with a LC‐10AD pump, a SPD‐10A UV/Vis detector, a CTO‐10AC column thermostat, and a manual sample injector was used to analyze S‐allyl cysteine content in extracts. The mobile phase consisted of 0.1% H3PO4 solution and acetonitrile (Sigma‐Aldrich) with isocratic elution. A flow rate of 0.5 ml/min and injection volume of 10 µl were applied. The analyte was separated using a LiChroCART® column (250 × 4 mm, 5 m, Merck KGaA) at room temperature, and SAC was detected at 210 nm.