Quality control method based on quartz crystal microbalance and WGA for flour milled from germinated wheat

• Published in: European food research & technology 2009-09, Vol.229 (5), p.833-840
• Main Authors: Radulescu, Maria-Cristina, Bucur, Bogdan, Bucur, Madalina Petruta, Radu, Gabriel Lucian
• Format: Article
• Language: English
• Subjects: Adsorption; Agriculture; Analytical Chemistry; Binding sites; Biological and medical sciences; Biotechnology; Carbohydrates; Caustic soda; Cereal and baking product industries; Chemistry; Chemistry and Materials Science; Crystals; Dietary minerals; Electrodes; Food; Food industries; Food Science; Forestry; Fundamental and applied biological sciences. Psychology; General aspects; Glucose; Gold; Lectins; Methods of analysis, processing and quality control, regulation, standards; Original Paper; Plant extracts; Proteins; Quality control; Quartz; R&D; Research & development; Seeds; Sodium; Studies; Triticum aestivum; Wheat
• ISSN: 1438-2377; 1438-2385
• DOI: 10.1007/s00217-009-1120-2

The flour obtained from germinated wheat has a low quality and may be identified by its increased content of a specific marker: a toxic lectin named wheat germ agglutinin (WGA). Quartz crystal microbalance was used to study the lectin-carbohydrate bioaffinity interactions. Sensors for two plant lectins: Concanavalin A (Con A) and WGA were obtained by immobilizing glucose on gold coated piezoelectric quartz crystals via thiol bonds. The limit of detection was 0.1 μg/mL for Con A and 0.5 μg/mL for WGA. The proposed method was sensitive enough to detect the biologically active WGA from whole meal flour samples produced using three types of wheat before and after 36 h of germination. The WGA amount in germinated wheat was increased by 17-36.9%. The obtained WGA recoveries from spiked samples were between 88.7 and 110.6%. The analysis method may be adapted for the determination of biologically active lectins from nutritional supplements based on the plant extracts.