300 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



prepared by Fischer by the partial hydrolysis of amygdalin and is 

 isomeric with sambunigrin (d-mandelonitrile glucoside) from the 

 leaves of Sambucus nigra and prulaurasin (di-mandelonitrile gluco- 

 side) from the leaves of Prunus laurocerasus. It also contains a 

 ferment resembling emulsin; /3-methylaesculetin (methyl ether of 

 di-hydroxy-coumarin) which probably occurs in combination as a 

 crystalline glucoside, the solutions giving a blue fluorescence; . 

 phytosterol; 1-mandelic acid, oleic acid; p-coumaric acid; tri- 

 methyl-gallic acid; ipuranol; dextrose; sugar; tannin 2.5 to 4.5 

 per cent; starch and calcium oxalate. The yield of hydrocyanic 

 acid varies from 0.23 to 0.32 per cent (inner bark) to 0.03 per cent 

 (trunk bark) and varies even in the bark of the same thickness 

 from the same tree. When the exposure is such that the chloro- 

 plastids are abundant in the cells of the bark, then the percentage of 

 the 1-mandelonitrile glucoside is higher, whereas when the exposure 

 is such that the cells do not take an active part in photosynthesis 

 the percentage . of the glucoside is lower. In the latter case the 

 bark is yellowish-brown. Nichols found from 3.19 to 3.70 per cent 

 amygdalin in bark on north side of trees and 2.60 to 2.97 per cent 

 in bark on south side of trees. On keeping the bark for a year it 

 deteriorates from 10 to 50 per cent. 



The bark of Prunus pseudo-cerasus var. Sieboldi of Japan 

 contains a glucoside (sakuranin) which crystallizes in needles and 

 is soluble in dilute alcohol, the solution being colored yellow with 

 ferric chloride. 



Adulterants. It is likely that the barks of other species of Prunus 

 are now entering the market. They are more astringent and less 

 aromatic. 



Allied Plants. The leaves of the Cherry laurel (Prunus Lauro- 

 Cerasus) are used in the fresh condition. They are oblong or oblong- 

 lanceolate, about 15 cm. in length, sharply serrate, coriaceous, with 

 an almond-like odor on being bruised and an aromatic, bitter taste. 

 They contain about 1.3 per cent of a glucoside laurocerasin, which is 

 associated with amygdalic acid; a ferment emulsin, which acts on 

 the laurocerasin, causing it to be more slowly decomposed than amyg- 

 dalin and yielding but half as much hydrocyanic acid (about 0.12 

 per cent) and benzaldehyde (about 0.5 per cent). The leaves also 

 contain a crystalline principle, phyllic acid, which is insoluble in 

 water, soluble in alcohol and occurs in the leaves of almond, peach 

 and apple. A glucoside resembling laurocerasin is found in the 

 leaves of Sambucus nigra. 



The leaves of the Peach (Persica vulgaris), which is extensively 



