FREEZE‐DRYING OF ALGAE: CHLOROPHYTA AND CHRYSOPHYTA1

Abstract
Thirty‐nine of 106 algal strains tested were successfully lyophilized using at least one of the following as suspending agents: 20% (w/v) skim milk, 12% (w/v) sucrose, 100% lamb serum and 100% horse serum. The majority of the Chlorella and Scenedesmusstrains tested (27/40) were amenable to freeze‐drying. Much less success (3/18) occurred with the Chlamydomonas strains tested. At least one strain of Ankistrodesmus, Bracteacoccus, Characium, Trebouxia, Haematococcus, Coccomyxa, Interfilum, Hormidium and Nephrodiella were also recovered. More strains were recovered with 20% skim milk as the protective agent than with 12% sucrose; however, 12% sucrose generally provided higher yields. Freeze‐drying appears to be an effective method of preservation far some algal strains.