CHEMICAL-STRUCTURE OF LIPID BIOFLOCCULANT PRODUCED BY RHODOCOCCUS-ERYTHROPOLIS

We have identified the chemical structure of the lipid bioflocculant p roduced by Rhodococcus erythropolis S-1 strain, It was hydrolyzed with alkali and decomposed to sugar and fatty acid fractions, The sugar fr action was identified as a mixture of glucose and trehalose by HPLC an d TLC analyses combined with acid and enzyme hydrolyses, The fatty aci d fraction was identified as a mixture of many molecular classes of my colic and mycoleic acids (2-alkyl-3-hydroxy long-chain fatty acids) of which the molecular masses were from 496 to 606 (C-32-C-40) with GC-M S analysis after methylesterification and trimethylsilylation. A gel p ermeation column chromatography study suggested that the lipid biofloc culant contained trehalose monomycolate, glucose monomycolate, and tre halose dimycolate. Furthermore, we showed that the lipid bioflocculant can be extracted directly from Rhodococcus erythropolis S-1 cells wit h organic solvents such as ethanol.