High CO2 partial pressure depresses productivity and bioenergetic growth yield of Chlorella pyrenoidosa culture

Abstract

When low-CO2 grown Chlorella pyrenoidosa (YSK strain) cells were exposed to high CO2 partial pressures (pCO2), the specific growth rate (μ) declined exponentially reaching a steady state value in about 20 h. A short interruption (up to 1 h) by temporarily lowering the pCO2 did not prevent the continuous decline in μ when high pCO2 was restored. In chemostate studies, light-limited cultures were supplied with 2 to 90 kPa of CO2. The steady state biomass production rate and bioenergetic growth yield were related inversely to pCO2 and the average energy uptake rate. The maintenance energy coefficient was, however, independent of dissolved pCO2 in the pCO2 range studied. © 1991 Kluwer Academic Publishers.