The Preliminary Detection of Cyanogenic Glycosides in Pra (Elateriospermum tapos Blume) by HPLC

Seeds of Pra (Elateriospermum tapos Blume) are normally fermented and eaten by local villagers in Southern Thailand, especially in Nakhon Si Thammarat province. It is well known that fresh seeds can make the person who eats them even in small amounts feel dizzy. The amounts and types of cyanogenic glycosides in the seeds and the effect of heat and fermentation on the amount of the substances have never been reported before. Amygdalin, a type of cyanogenic glycoside, was detected in this preliminary study. It was found that fresh leaves contained 30 ppm of amygdalin, while fresh seeds contained much more amygdalin; 660 ppm, equivalent to a small amount of HCN, 0.005 ppm. Cooked and later fermented seeds had considerably less amygdalin than the fresh ones, 100 ppm and 25 ppm, respectively. It is clearly shown that heat (boiling) and fermentation can reduce the amount of amygdalin in the seeds.