According to van Romburgh, the leaves of Indigofera galegoides, DC. (family Leguminosae) contain a substance (probably amygdalin) which reacts with emulsin forming hydrocyanic acid and benzaldehyde. Upon distilling the fresh herb, mashed with water, 0,2 p.c. of oil were obtained.
Indigofera oil is light yellow and has the odor of bitter almond oil but differs from it by an herbaceous odor. Sp. gr. 1,046').
In addition to benzaldehyde and hydrocyanic acid, the oil contains traces of ethyl alcohol and small amounts of methyl alcohol. The presence of the latter was demonstrated by its conversion into methyl iodide and into methyl oxalate melting at 54o.
When previous to the distillation the leaves were digested with water at 50° for 24 hours, the first distillate contained large amounts of ethyl alcohol in addition to methyl alcohol. The ethyl alcohol apparently is formed when the leaves are soaked in water2).