피마자(Ricinus communis)의 씨로부터 독성물질인 ricin을 DEAE-cellulose와 Sepharose-4B column을 이용하여 정제하였다. 분리된 ricin은 $K_{562}$ 세포의 증식을 억제시켰으며 적혈구 응집력이 있었다. 적혈구 응집력은 ricinus agglutinin이 갖는 응집력의 0.3%에 불과 했으며, 응집력의 억제는 galactose나 lactose, melibiose, 또 galactose를 포함하지 않은 ${alpha}-L-rhamnose$나 L(+)arabinose에 의하여 일어났다. Ricin을 주입받은 ICR생쥐는 60ng에서 나흘만에 반이 치사되였다.
The toxic lectin, ricin, present in the seeds of Korean castor bean, Ricinus communis, have been isolated and the biochemical properties were studied. The isolation procedure involves ion exchange chromatography on DEAE-cellulose, affinity chromatography on Sepharose 4B column. The multiplication rate of $K_{562}$ cell decreased and the death rate increased proportionally by the addition of the isolated ricin. It has hemagglutination activity but only 0.3% of the activity of the other lectin, ricinus agglutinin. The activity was inhibited by lactose, melibiose, galactose as well as ${alpha}-L-rhamnose$ and L-arabinose. A dose of 60 ng of ricin caused death in 50% after 4 days in ICR mice.
