title: Pitfalls in the desulphation of glucosinolates in a high-throughput assay.
abstract: Glucosinolates are phytochemicals with health promoting properties. Determination as desulpho-glucosinolates is widely used and a desulphation in microtiter plates has been applied to reach high throughput. The use of various sulphatase concentrations and volumes throughout literature necessitates the identification of an appropriate desulphation procedure in microtiter plates. High sulphatase concentrations (≥15 mg/ml) decreased the concentration of the internal standard glucotropaeolin, whereas the other glucosinolates were less affected. Due to the calculation based on the recovery of glucotropaeolin, this leads to an overestimation of GL concentrations after desulphation with high sulphatase concentrations. A glucosidase side-activity, present in the crude sulphatase powder, is likely causing this phenomenon. At lower sulphatase concentrations (1 mg/ml) glucoiberin and glucoraphanin were insufficiently desulphated. Combining these effects results in a small range of applicable sulphatase concentrations. A purified sulphatase preparation resulted in good recoveries for a diversity of samples and is hence recommended for high throughput desulphation in microtiter plates.
authors: Product Design and Quality Management Group, Department of Agrotechnology and Food Sciences, Wageningen University, P.O. Box 8129, NL-6700 EV Wageningen, The Netherlands. kristin.hennig@wur.nl
authors: K
authors: K
authors: Hennig
authors: R
authors: R
authors: Verkerk
authors: G
authors: G
authors: Bonnema
authors: M
authors: M
authors: Dekker
mesh_terms: D001937:Brassica / Q000737:chemistry / Q000201:enzymology*; D005961:Glucosinolates / Q000737:chemistry*; D057166:High-Throughput Screening Assays / Q000295:instrumentation / Q000379:methods*; D010940:Plant Proteins / Q000032:analysis / Q000302:isolation & purification; D013429:Sulfatases / Q000032:analysis / Q000302:isolation & purification
chemical_list: D005961:Glucosinolates; D010940:Plant Proteins; D013429:Sulfatases