Identification and quantification of glucosinolates in different tissues of Raphanus raphanistrum by mass spectrometry

This study aims to identify and quantify the glucosinolates from different parts of wild radish R. raphanistrum (leaves, flowers, fruits, roots) using liquid chromatography-tandem mass spectrometry. Glucoraphenin is the predominant compound, accounting for about 87% (w/w) of total glucosinolate content, followed by glucobrassicin, glucoraphasatin and glucoraphanin (153 mg 100 g-1, 149 mg 100 g-1 and 141 mg 100 g-1 FW, respectively) in fruits; followed by glucoraphasatin (3 mg 100 g-1 FW) in flowers and by glucobrassicin, 4-hydroxyglucobrassicin and glucoraphasatin (145 mg 100 g-1, 27 mg 100 g-1 and 24 mg 100 g-1 FW, respectively) in leaves. In roots the major glucosinolate is glucoraphasatin (56 mg 100 g-1 FW) followed by the glucoraphenin and methoxyglucobrassicin (16 mg 100 g-1 and 7 mg 100 g-1 FW, respectively). Principal component analysis allowed the discrimination of fruit samples from other parts of the plant for the majority of glucosinolates and the fruits are highlighted as sources of glucosinolates. The results are interesting given that wild radish is one of the most important weeds of crops in the Mediterranean region and is popular for home vegetable production and for its employment in human nutrition both as a food as well as for medicinal purposes.