THE INFLUENCE OF EXTRACTION CONDITIONS AND CHROMATOGRAPHIC SEPARATION ON THE ABILITY OF IDENTIFYING GLIADINS FROM THE WHEAT FLOUR
Consulting and Training Centre, KEY
Cereal proteins play an important role in the humans’ and animals’ diet, due to their nutritional composition and functional properties in food production. One of these proteins is gluten. It contains protein components that are present as monomers and interconnected by disulfide bonding polymers. Based on their solubility in an aqueous alcohol, gluten proteins are divided into soluble gliadins and insoluble glutenins. Apart from the beneficial nutritional composition and importance in food production, gluten also causes adverse health effects in susceptible individuals, such as celiac disease. In this paper, gliadin proteins have been analyzed in wheat flour by high-pressure liquid chromatography of reversed phases (RP-HPLC). The influence of different concentrations of ethanol (30%, 40% and 50%) and column temperature (40 C, 45 C and 50 C) was investigated to achieve better chromatographic separation and identification of gliadin proteins. The chromatographic separation of gliadin proteins was carried out on the column Zorbax 300 SB-C3 (Agilent) and the Agilent Technologies 1260 Infinity HPLC apparatus has been used. After extraction gliadin proteins with 30% (v/v) ethanol, the number of identified proteins was 20, after extraction with 40% (v/v) ethanol was 21 and with 50% (v/v) ethanol was 24, at a temperature of 40 C. By increasing the column temperature (45 oC and 50 oC), the number of identified proteins after extraction with 30% ethanol was 17 and 20, after extraction with 40% ethanol was 25 and 24, and after extraction with 50% ethanol was 26 and 24. Based on the obtained results, the largest number of gliadin proteins was identified by extraction with 50% ethanol and at a column temperature of 45 C. By increasing the column temperature to 50 oC, the number of identified proteins decreases.
Gliadins, Ethanol, High-pressure liquid chromatography of reversed phases (RP-HPLC).