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Di(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer, which is considered an endocrine disrupting pollutant. Growth kinetics and esterases activity by biochemical tests and polyacrylamide gel electrophoresis were characterized for Fusarium culmorum grown in DEHP-supplemented (1000 mg/L) medium as the only carbon source and in control medium with glucose. Intermediate compounds of biodegraded DEHP were identified by GC-MS. F. culmorum degraded 92% of DEHP within 36 h. DEHP was degraded to butanol, hexanal, catechol and acetic acid. It is suggested that the first two compounds would transform into butanediol and the last two would enter into the Krebs cycle and would be mineralized to CO 2 and H 2 O. DEHP induced eight esterase isoforms, which were different to those constitutive isoforms produced in the control medium. It is suggested that five enzymes (25.7, 29.5, 31.8, 97.6 and 144.5 kDa) detected during the first 36 h be involved in the primary biodegradation of DEHP. The rest of the enzymes (45.9, 66.6 and 202.9 kDa) might be involved in the final steps for DEHP metabolism. F. culmorum has a promising practical application in the treatment of DEHP-contaminated environments because it can secrete specific esterase to breakdown high concentrations of DEHP in a short period of time. This research represents the first approach for the study of esterase involved in the DEHP degradation by fungi using this phthalate as the sole source of carbon and energy., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Abstract Dibutyl phthalate (DBP) is a plasticizer, whose presence in the environment as a pollutant has attained a great deal of attention due to its reported association with endocrine system disturbances on animals. Growth parameters, glucose uptake, percentage of removal efficiency (%E) of DBP, biodegradation constant of DBP (k) and half-life of DBP biodegradation (t 1/2) were evaluated for Pleurotus ostreatus grown on media containing glucose and different concentrations of DBP (0, 500 and 1000 mg l−1). P. ostreatus degraded 99.6 % and 94 % of 500 and 1000 mg of DBP l−1 after 312 h and 504 h, respectively. The k was 0.0155 h−1 and 0.0043 h−1 for 500 and 1000 mg of DBP l−1, respectively. t 1/2 was 44.7 h and 161 h for 500 and 1000 mg of DBP l−1, respectively. Intermediate compounds of biodegraded DBP were identified by GC-MS and a DBP biodegradation pathway was proposed using quantum chemical calculation. DBP might be metabolized to benzene and acetyl acetate, the first would be oxidated to muconic acid and the latter would enter into the Krebs cycle. P. ostreatus has the ability to degrade DBP and utilizes it as source of carbon and energy. Highlights • Pleurotus ostreatus degraded 99.6 % of DBP after 312 h. • Half-life of DBP biodegradation was 44 h. • DBP biodegradation pathway was proposed using quantum chemical calculation. • DBP might be metabolized through de-esterification and oxidation pathways. • P. ostreatus has the ability to degrade high concentrations of DBP. [ABSTRACT FROM AUTHOR]