Thermal characteristics of Spirulina platensis cells under nongrowing conditions at various values of pH medium.
The total value of heat (-Q) evolved by green-blue microalgae Spirulina platensis cells in a dark and stationary regime in the range of pH values 8.0-11.6 was determined. It was established that (-Q) reaches its maximum value at 360 +/- 40 J/g of dry biomass in the pH range 9.3-10.3 and then sharply dropped relative to these values and reached zero at pH 7.5 +/- 0.2 and 11.8 +/- 0.2. It is affirmed that an optimum regime for preservation of Spirulina platensis cell viability in a dark and stationary regime is pH range 9.3-10.3. It was also shown that the peak of heat evolution with maximum about 45 degrees C, reflecting mainly the respiration of cells (oxygen absorption rate), did not displace along the temperature scale at a change of pH from 9.3 to 10.4 and slightly displaced lower and higher of these values of pH. It is supposed that the thermostability of biomacromolecules and their complexes responsible for cell respiration does not depend on pH medium in pH range 9.3-10.3.
Monaselidze
J
J
Institute of Physics of the Georgian Academy of Sciences, 380077 Tbilisi, Georgia. mon@iph.hepi.edu.ge
Barbakadze
Sh
Sh
Kvirikashvili
Sh
Sh
Majagaladze
G
G
Khachidze
D
D
Topchishvili
L
L
D002153:Calorimetry, Indirect; D019069:Cell Respiration; D003470:Culture Media; D000458:Cyanobacteria / Q000378:metabolism*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration
D003470:Culture Media