ENRICHMENT, ISOLATION AND CHARACTERIZATION OF DIALKYL SULFOSUCCINATE DEGRADING BACTERIA COMAMONAS-TERRIGENA N3H AND COMAMONAS-TERRIGENA N1C

Microorganisms derived from soil, sludge, sewage or river water contam inated by detergents or mineral oils were enriched and tested for the capability of primary biodegradation of dialkyl sulfosuccinates (DASS) . Adapted mixed cultures, containing predominantly Gram-negative bacte ria, degraded di-n-hexyl sulfosuccinate (DHSS) more readily than di-n- octyl sulfosuccinate (DOSS). Bacterial isolates obtained from enriched mixed cultures that show the highest rates of primary biodegradation and assimilation of DASS belong to the genus Comamonas. Under nongrowt h conditions, the DHSS primary biodegradation by these strains follows the Ist order reaction kinetics. The rate constants of primary degrad ation of DHSS by resting cells of C. terrigena N3H were found to be 30 times higher than when catalyzed by C. terrigena N1C. The capacity fo r accelerated removal of surface-active properties of DHSS by C. terri gena N3H was retained within the range of pH 4-10 and at temperatures up to 55 degrees C, while DHSS degradation by C. terrigena N1C was com pletely inhibited above 48 degrees C. Temperature and pH limits for DH SS primary degradation by both strains were to a great extent wider th an those for the viability of the cultures. Biodegradation capacity an d metabolic stability of C, terrigena N3H make this strain interesting from both scientific and technological point of view.