| Abstract: | The chemical structure determining properties and biological functions of endotoxins derived from Desulfovibrio desulfuricans species has not been recognized, which considerably hinders the choice of an effective extraction procedure of these lipopolysaccharides (LPS) from the bacterial outer cell membrane. We aimed at selecting the most effective method of LPS isolation from D. desulfuricans in terms of the most efficient extraction solution, the appropriate conditions of isolation and adequate purification technique. For this purpose we tested a few literature-based procedures utilizing various extraction mixtures (phenol-water, phenol-chloroform-petroleum ether and Tri-Reagent, i.e. aqueous solution of guanidinum thiocyanate and phenol). The best yield and purity of the isolated LPS were provided by the application of the extraction with phenol-water according to the modified by Shnyra et.al. (2000) procedure of Westphal et. al. (1952). A satisfactory method of isolation in micro scale appeared to be that based on Tri-Reagent and propagated by Yi and Hackett in 2000. The extraction of LPS from D. desulfuricans with phenol-chloroform-petroleum ether should not be recommended due to its low efficiency. |
