Boiled Brussels sprouts: A rich source of glucosinolates and the corresponding nitriles

Abstract

This study identified glucosinolate (GLS) breakdown products and determined the relationships between such products and parent GLS in boiled Brussels sprouts. This is the first ever study to analyse all groups of GLS breakdown products (aliphatic, aralkyl and indole) in boiled vegetables. In the examined boiled Brussels sprouts, isothiocyanates were not determined in the edible parts or cooking water. The presence of seven breakdown products was determined as indole-3-acetonitrile, indole-3-carbinol, ascorbigen and 3,3'-diindolylmethane released form glucobrassicin, 3-butenylnitrile released from sinigrin, 4-methylsulfinylbutanenitrile released from glucoiberin, and 2-phenylacetonitrile released from gluconasturtiin. In the edible parts, the content of indole-3-acetonitrile and 3-butenylnitrile was particularly high at approximately 30 and 16 µmol/100 g FW, which was equivalent to 54 and 9% of the initial value of the parent GLS, respectively.

Keywords

• Brassica vegetables
• Phytochemicals
• Sinigrin
• Glucobrassicin
• 3-butenylnitrile
• Indole-3-acetonitrile