진주조개, Pinctada fucata martensii 담륜자의 냉동보존을 위한 동해방지제의 선택

Selection of Cryoprotectants for Cryopreservation of Pearl Oyster, Pinctada fucata martensii Trochophore

우리나라에서 진주양식의 대상패류인 진주조개 (Pinctada fucata martensii) 담륜자를 냉동보존하기 위하여 4가지 동해방지제를 사용하여 냉동실험을 실시하고, 적합한 동해방지제를 찾고자 하였다. 동해방지제인 dimethyl sulfoxide (DMSO), ethylene glycol, glycerol과 1, 2-propanediol을 희석액인 0.2 M sucrose에 각각 0.01, 0.1, 1.0과 2.0 M이 되도록 혼합한 다음, 10분간 평형상태를 유지한 후 냉동하였다. 냉동후 해동시킨 담륜자는 모든 동해방지제에서 농도가 증가할수록 생존율이 높아졌으나, 일부 세포내 함유물이 세포외로 유출되어 손상을 입은 개체도 보였다. 진주조개의 담륜자 냉동보존에 적합한 동해방지제는 1.0∼2.0 M의 DMSO와 ethylene gly-col로서 해동후 생존율이 82.8∼97.4%로 가장 높았다.

To find out the desirable cryoprotectant for cryopreservation of bivalve trochophores, four types of cryoprotectant were tested with trochophores of the pearl oyster (pinctada fucata martensii) generally used in the pearl production in Korea. Each cryoprotectant (dimethyl sulfoxide, ethylene glycol, glycerol and 1,2-propanediol) was mixed with 0.2 M sucrose to make final concentrations of 0.01, 0.1, 1.0 and 2.0 M. The trochophores were immersed in each preparation, waiting for 10 minutes to reach equilibration and cryopreserved in the liquid nitrogen (-l96$^{\circ}C$). Survival rate of trochophores thawed after cryopreservation increased as the media concentration increase. However, a few number of the trochophores seemed to be damaged with the efflux of cell inclusions. Our study rsults indicate that desirable cryoprotectants for cryopreservation of pearl oyster trochophores are 1.0~2.0 M dimethyl sulfoxide and ethylene glycol : 82.8~97.4% of the trochophores cryopreserved with these media survived after thawing.