Microbial degradation of phthalate esters. I. Isolation of microorganisms growing on phthalate esters and degradation of phthalate esters by Pseudomonas acidovorans 256-1.

Abstract

Many microorganisms (17 strains of gram-positive bacteria, 8 strains of gram-negative bacteria, 2 strains of fungi) capable of assimilating di-2-ethyl hexyl phthalate (DEHP) were isolated from soil and other natural sources. When Pseudomonas acidovorans 256-1 among these microorganisms was aerobically cultured in media containing 0.5% of DEHP, DEHP disappeared completely in 72 hr when assayed gaschromatographically. Most of phthalate esters could be assimilated, regardless of their side-chain types. In addition, branched-alkyl phthalate was assimilated better than n-alkyl phthalate. Based on degradation rate of n-alkyl phthalate in relation to its side chain and carbon number, two peaks were observed in n-alkyl phthalate with four and seven carbon number on its side-chain.