초록
<P><B>Abstract</B></P> <P>The cellular PHB content was determined in 137 strains of cyanobacteria representing 88 species in 26 genera under six photoautotrophic nutrient conditions. One hundred and thirty-four strains were PHB producers. The PHB contents of these 134 strains were subtle under normal growth condition, but were significantly increased in 63 strains under nitrogen deprivation (–N), a higher frequency than with phosphate and/or potassium and all-nutrient deprivation. A high PHB accumulation was not associated with any particular evolutionary groups, but was strain specific. The filamentous <I>Calothrix scytonemicola</I> TISTR 8095 produced 356.5±63.4mg/L PHB under –N from a biomass of 1396.6±66.1mg/L, giving a PHB content of 25.4±3.5% (w/w dry weight). This PHB productivity is equivalent to the CO<SUB>2</SUB> consumption of 729.2±129.8mg/L. The maximum energy conversion from solar energy to PHB obtained by <I>C. scytonemicola</I> TISTR 8095 was 1.42±0.30%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The presence of PHB production in divergent cyanobacteria. </LI> <LI> The specific nutrient conditions that increased PHB accumulations in the specific strains. </LI> <LI> Experimental mean to optimize efficiency of energy conversion from solar energy to PHB proceeded by cyanobacteria. </LI> </UL> </P>