FIG. 2.

500 MHz ¹H-NMR spectrum (A) and 125 MHz ¹³C-NMR spectrum (B) of PHA synthesized by P. fluorescens BM07 cells grown on 70 mM fructose at 25°C. For the inserted doublet peaks (B), the downfield peaks are associated with saturated monomer units and the upfield ones are due to unsaturated monomer units (C_12:1, C_14:1, etc.). Thus, from the peak area ratios of the doublets, the relative amount of total unsaturated monomers in PHA can be calculated. The calculated percentage of unsaturated monomer units was 38%, a result that agreed well with the percentage determined by GC (37%). See the text for details.