Cell damage and recovery in cryopreserved microphytobenthic diatoms.
Two pennate microphytobenthic diatoms, Amphora coffeaeformis (Agardh) Kutzing and Navicula transitans var. derasa f. delicatula Heimdal, were cryopreserved and monitored on thawing to track the mechanical injuries and their post-preservation recovery. Cells were subjected to (1) direct freezing in liquid nitrogen and (2) two-step cooling with and without the cryoprotectant, dimethyl sulfoxide (Me(2)SO). Mechanical injury due to exposure to low temperature differed between the two species. While A. coffeaeformis cells were intact and could survive even direct freezing without a cryoprotectant, N. delicatula cell chloroplasts were damaged. However, the two-step cooling along with a cryoprotectant minimized the mechanical injury to cells of both species thereby enhancing the post-thaw viability.
Mitbavkar
Smita
S
Marine Corrosion and Materials Research Division, National Institute of Oceanography, Dona Paula, Goa 403 004, India.
Anil
Arga Chandrashekar
AC
D002736:Chloroplasts / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D017377:Diatoms / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D013314:Stress, Mechanical
D004121:Dimethyl Sulfoxide