Publication details

The effect of shock freezing on physiological properties and consequent growth of Antarctic filamentous (Stigeoclonium sp.) and coccal alga (Diplosphaera chodatii) on agar plates

Investor logo


Year of publication 2019
Type Article in Periodical
Magazine / Source Czech Polar Reports
MU Faculty or unit

Faculty of Science

Web Full Text
Keywords Antarctica; cold stress; cryoresistance; algal cultures; biotechnologies
Attached files
Description In this study, we investigated the effects of shock freezing on physiological properties and consequent growth of in the Antarctic alga Stigeoclonium sp. and comparative coccal alga Diplosphaera chodatii on agar plates. Culture of algae grown in liquid medium were used to study subzero temperatures on the species resistance to shock freezing. Then, microalgae were frozen in liquid nitrogen and inoculated on BBM agar after thawing. Physiological status of algae was evaluated by chlorophyll fluorescence parameters during 28 days. The results showed that interspecific differences existed in their tolerance to shock freezing, as well as their consequent growth rate on agars. Direct effects of freezing in liquid nitrogen was demonstrated in chlorophyll fluorescence parameters recorded immediately after thawing the samples (in liquid medium). In spite of the fact that majority of cells was destroyed by shock freezing, the potential of photochemical processes in PS II (FV/FM) remained constant in D. chodatii. It may indicate high resistance of the species to freezing/thawing cycles and a capability of the surviving cells, core chlorophylls in PS II respectively, to perform photosynthetic processes related to PS II. Contrastingly, Stigeoclonium sp. showed a shock freezing-dependent decrease in FV/FM. When shock-frozen, thawed and inoculated on agar plates, the culture of D. chodatii, and Stigeoclonium sp. showed cultivation time-dependent increase in chlorophyll fluorescence parameters (FV/FM, FS).
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.

More info