test method:hplc. herb source:first isolated from bitter almnds ,seeds of prunus amygdalus (rosaceae);the sugar moiety is gentiobiose ;this is typical for seeds of many members of rosaceae,and trace amounts may be preent in the fleshy parts of fruits ,in bark and leaves;also it is found in subterranean parts of gerbera jamesomii cultivars (compositae )together with vicianin(q.v.)and prunasin(q.v.).an isomer of amygdalin with sophorose(q.v.)instead of gentiobiose(q.v.) as the leaves of perilla frutescens (labiatae). synonyms:amygdaloside;mandelonitrile-β-gentiobioside . molecular formula: c20h27no11 . molecular weight: 457.44 . physics properties:square crystal ,melting point 2000c, soluble in the water ,ethanol, hardly soluble in the aether. pharmacology function:it has been used ,interchangeably with mandelonitrile-β-glucuronide ,as the drug “laetrile”for treating cancer ,but is ineffective .amygdalin is responsible for the bitterness and toxicity of the seeds of bitter almond (100umolg-1)and of apricots (20-80umol g-1).minimum lethal dose to human of hydrogen cyanide is 0.5-3.5 mg per kg body weight.