Objective: To evaluate the existing form of amygdalin in bitter almond and the influence of temperature and acid-base on isomerization of amygdalin. Method: Use high performance liquid chromatography (HPLC) to determine the peak area of D-amygdalin and L-amygdalin in different decocting temperature

and use this method qualitatively investigate the influence of acid-base on isomerization of amygdalin monomer. Result: Amygdalin in Semen Armeniacae Amarum in different temperatures have different isomerization performance; amygdalin monomer did not occur isomerization in acid environment

isomerization under the effect of ammonia

sodium hydroxide. Conclusion: With the rise of decocting temperature results in the peak area of D-amygdalin and L-amygdalin gradually increased. Amygdalin monomer is stable in the acidic environment

alkali lead one of the factors of isomerization.