자유생환 아메바를 효과적으로 유지할 목적으로 냉동보관을 시도하였다. Glycerol과 Dimethylsulfoxide를 각 각 최종농도 7.5%가 되도록 아메바현탁액에 첨가하였다. 아매바 영양형을 냉동하는 과정에서 온도 하강속도가 빠를때 (평균 $1.3^{circ}C/min$)보다 느릴때 (평균 $0.7^{circ}C/min$) 생존력이 더 높았다. 액체질소 속에서 60일동안 보관한 후의 생존율은 처음 넣어준 아메바 영양형 수의 2~39%에 달하였다. 냉동 보관했던 아메바를 해동했을 때 어떤 형태적 변화나 배양했을 때의 문제점도 관찰되지 않았다.
We have successfully cryopreserved free-living amoebae in order to maintain them feasibly under the conditions in our laboratory. The viability of trophozoites was higher when frozen by slow cooling (overall 0.7℃/min) than by fast cooling (overall 1.3℃/min). Glycerol and dimethylsulfoxide at the final concentration of 7.5% each was used for cryopreservation of free-living amoebae trophosoites. The survival rate was 2∼39% after storage in the liquid nitrogen for 60 days. Gross cultural or morphological changes were not noted in trophozoites thawed from frozen suspensions, Key wards: Cryopreservation, free.living amoebae, survival rate, liquid nitrogen
