Determination of Cyanogenic Glycoside in Seeds by Molecular Absorption Spectrometry in the Gas Phase

Abstract

Abstract As a means of evaluating cyanogenic glycoside content, cyanide was determined in apple, cherry, almond, and peach seeds. Sample preparation involved enzymatic hydrolysis and collection of hydrogen cyanide in strong base. For analysis, cyanide was converted to ammonium by addition of excess KMn04 followed by treatment with H2S04, and the resulting NH4+ was determined by the novel gas-phase molecular absorption spectrometric technique. An atomic absorption spectrophotometer, with a flow-through absorption cell replacing the flame, was used in the analysis. Recovery of amygdalin was 98.4 ± 1.2% complete. Cyanogenic glycoside contents determined in seeds (0.93% for apple, 2.05% for cherry, 2.43% for peach, and 0.00% for almond, reported in terms of amygdalin), were confirmed by a standard titration method. The lowest detectable concentration was 0.2 μg NH4+/mL, which corresponds to a detection limit of 0.5 mg amygdalin in the seed sample.