Abstract
We attempted to cryopreserved cultured Ceratopteris thalictroides cells in liquid nitrogen. Callus cells
cryoptrotected with 5% (v/v) DMSO and 10% (w/v) glucose were cooled at a rate of 1℃/min to different
temperature in a programmed freezer, then immersed in liquid nitrogen. Callus cells cooled to -10 or -20℃
survived and regrew. However, regrowth of cells cooled and preserved in liquid nitrogen was not recognized.
According to TTC assay, viability of preserved cells in liquid nitrogen were high enough to survive
immediately after thawing but it decreased rapidly to low level within 24 h of post thaw culture. These
results suggest that further improvements are important for enhancement of survival rate after preservation.
