Biosynthesis of polyhydroxyalkanoates from low-rank coal liquefaction products by Pseudomonas oleovorans and Rhodococcus ruber

A screening identified several bacteria that were able to use chemically he terogeneous low-rank coal liquefaction products as complex carbon sources f or growth. Pseudomonas oleovorans and Rhodococcus ruber accumulated polyhyd roxyalkanoic acids (PHA) amounting to 2%-8% of the cell dry weight when the cells were cultivated on these liquefaction products in the absence of any other carbon source. R. ruber accumulated, in addition to PHA, small amoun ts of triacylglycerols. The accumulated PHA consisted of 3-hydroxyhexanoate , 3-hydroxydecanoate, and 3-hydroxydodecanoate (P. oleovorans) or 3-hydroxy butyric acid and 3-hydroxyvaleric acid (R. ruber). I,ow-rank coal liquefact ion products obtained from Trichoderma atroviride were better substrates fo r P. olesvorans than chemically produced fulvic acids.