DEVELOPMENT OF A MICROCOLORIMETRIC METHOD FORTHE DETECTION OF PHENOLIC LIPIDS IN CEREAL GRAINS

PLITMAN, F.; CATALÁN, C. A. N.; SAMPIETRO, D. A.

Tafi del Valle

Congreso; XXVIII Annual scientific meeting of the Tucuman biology association; 2011

Tucuman biology association

A new microcolorimetric method was developed to quantify 5-n-alkylresorcinols (5-n-ARs) in cereal grains. Orcinol and olivetol were exposed at a wide range of concentrations to different organic solvents, concentrations of Fast Blue RR reagent and basifying reagents .Absorbance was measured in a microplate reader at 450 nm. The influence of temperature and sunlight on the stability of the reaction products was also evaluated. The reaction was optimized and results were compared with those obtained using the Fast Blue B reagent. Contents of 5-n-A Rs were measured in ground and intact grains using both the optimized reaction and the Fast Blue B reaction. Absorbance linearly increased with olivetol and orcinol concentrations between 1-20 µg/ml using methanol or ethanol as solvent (A= 490 nm), Fast Blue RR at 0.0 25% and K2CO3 at 5%. This reaction was completed after 15 min of incubation at room temperature. Content of 5-n-ARs determined by the new microcolorimetric reaction were similar to those measured by the Fast Blue B reaction in both ground and intact grains. The new microcolorimetric technique requires less time and allows processing of a larger number of samples than the reaction based on Fast Blue B.