At the Australian National Algae Culture Collection (ANACC), we maintain ~1100 living strains, most of Australian origin, that we provide to industry, Universities and research. Living strains are maintained through serial sub-culturing, while this provides ready access to cultures it requires extensive maintenance and laboratory support. Expanding a culture collection involves both additional staff and growth spaces. Cryopreservation has been used by major algae collections for backing up their living collections, managing ongoing maintenance costs and minimizing genetic drift in cultures. Our newly established biobank features strains from several algal classes cryopreserved using DMSO as the cryoprotectant.
The success of recovery from frozen cultures varies depending on the strain. To optimize recovery, we monitored the growth of cryopreserved strains assessing the effects of varied light introduction and thawing protocols on post-thaw culture growth. We found culture recovery was more varied between the different taxa and that few strains exhibited a significant change in recovery when comparing a short light acclimation of 24hrs to a longer stepwise light acclimation over 3 days.