Optimized extraction, separation and quantification of twelve intact glucosinolates in broccoli leaves.
A new method has been developed and validated to determine twelve intact glucosinolates (glucoiberin, GIB; glucoraphanin, GRA; glucoerucin GER; gluconapin, GNA; glucotropaeolin, GTL; glucobrassicin, GBC; gluconasturtiin, GST; glucoalyssin, ALY; 4-hydroxyglucobrassicin, 4-OH; 4-metoxyglucobrassicin, 4ME; neoglucobrassicin, NEO; sinigrin, SIN) in broccoli leaves using liquid chromatography (LC) coupled to diode array (DAD) and electrospray ionization mass spectrometry (ESI-MS) detection. An extraction procedure has also been proposed and optimized by means of statistical analysis (the Box-Behnken design and analysis of variance); this is based on the deactivation of myrosinase using a microwave and heated water. Low limits of detection and quantification were obtained, ranging from 10 to 72 μg/g with DAD and 0.01 to 0.23 μg/g with ESI-MS, and the resulting recovery values ranged from 87% to 106% in all cases. Finally, glucosinolates were analyzed in broccoli leaf samples from six different cultivars (Ramoso calabrese Parthenon, Marathon, Nubia, Naxos and Viola).
IU CINQUIMA, Analytical Chemistry Group, University of Valladolid, 47011 Valladolid, Spain.
Ana M
AM
Ares
IU CINQUIMA, Analytical Chemistry Group, University of Valladolid, 47011 Valladolid, Spain.
María J
MJ
Nozal
IU CINQUIMA, Analytical Chemistry Group, University of Valladolid, 47011 Valladolid, Spain.
José L
JL
Bernal
IU CINQUIMA, Analytical Chemistry Group, University of Valladolid, 47011 Valladolid, Spain. Electronic address: jose.bernal@qa.uva.es.
José
J
Bernal
D053000:Analytic Sample Preparation Methods / Q000379:methods*; D001937:Brassica / Q000737:chemistry*; D005961:Glucosinolates / Q000737:chemistry* / Q000302:isolation & purification*; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification*; D018515:Plant Leaves / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D005961:Glucosinolates; D010936:Plant Extracts
Box–Behnken design; Broccoli leaves; Glucosinolates; LC-DAD–ESI-MS; Microwave extraction