Biodegradation of Di-(2-ethylhexyl) Phthalate by Rhodococcus ruber YC-YT1 in Contaminated Water and Soil

Abstract

Di-(2-ethylehxyl) phthalate (DEHP) is one of the most broadly representative phthalic acid esters (PAEs) used as a plasticizer in polyvinyl chloride (PVC) production, and is considered to be an endocrine-disrupting chemical. DEHP and its monoester metabolites are responsible for adverse effects on human health. An efficient DEHP-degrading bacterial strain Rhodococcus ruber YC-YT1, with super salt tolerance (0–12% NaCl), is the first DEHP-degrader isolated from marine plastic debris found in coastal saline seawater. Strain YC-YT1 completely degraded 100 mg/L DEHP within three days (pH 7.0, 30 °C). According to high-performance liquid chromatography–mass spectrometry (HPLC-MS) analysis, DEHP was transformed by strain YC-YT1 into phthalate (PA) via mono (2-ethylehxyl) phthalate (MEHP), then PA was used for cell growth. Furthermore, YC-YT1 metabolized initial concentrations of DEHP ranging from 0.5 to 1000 mg/L. Especially, YC-YT1 degraded up to 60% of the 0.5 mg/L initial DEHP concentration. Moreover, compared with previous reports, strain YC-YT1 had the largest substrate spectrum, degrading up to 13 kinds of PAEs as well as diphenyl, p-nitrophenol, PA, benzoic acid, phenol, protocatechuic acid, salicylic acid, catechol, and 1,2,3,3-tetrachlorobenzene. The excellent environmental adaptability of strain YC-YT1 contributed to its ability to adjust its cell surface hydrophobicity (CSH) so that 79.7–95.9% of DEHP-contaminated agricultural soil, river water, coastal sediment, and coastal seawater were remedied. These results demonstrate that R. ruber YC-YT1 has vast potential to bioremediate various DEHP-contaminated environments, especially in saline environments.

Study on biodegradation kinetics of di-2-ethylhexyl phthalate by newly isolated halotolerant Ochrobactrum anthropi strain L1-W

“…In the current study, degradation kinetics have revealed that the strain L1-W could degrade 98.7% of DEHP within 72 h when the initial concentration was 200 mg/L. Yang et al [25] isolated Rhodococcus rubber strain YC-YT1 that could degrade 60% of DEHP after 3 days given that the initial concentration was 0.5 mg/L. Xu et al [11] isolated Acinetobacter sp.…”

“…Despite this, in the current study, strain L1-W showed a high salinity tolerance up to 100 g/L which suggests that it may reduce the cost of desalinization in solid and wastewater treatment. Many halotolerant phthalates degraders have been isolated from marine environments [25,26]. Yang et al [25] isolated strain Rhodococcus ruber YC-YT1 from saline water which could tolerate up to 120 g/L of NaCl.…”

“…Many halotolerant phthalates degraders have been isolated from marine environments [25,26]. Yang et al [25] isolated strain Rhodococcus ruber YC-YT1 from saline water which could tolerate up to 120 g/L of NaCl. A study conducted by Jin et al [27] has identified halotolerant isolate-Sphingobium sp.-which degraded DBP at the salinity ranging from 0 to 4%.…”

“…In the current study, strain L1-W remained viable and active at the lowest and highest concentration of DEHP at 0.5 mg/L and 600 mg/L respectively. A study conducted by Yang et al [25] reported that a strain Rhodococcus ruber YC-YT1 could survive and remain active at 0.5 mg/L and 1000 mg/L concentrations of DEHP. Nahurira et.…”

Biodegradation of Di (2-Ethylhexyl) Phthalate by a novel Enterobacter spp. Strain YC-IL1 Isolated from Polluted Soil, Mila, Algeria

“…Bioremediation represents an excellent choice due to its superior safety and cost effectiveness. In this scenario, numerous strains have been isolated and implemented for bioremediation purposes [ 30 , 31 , 42 ]. In the present study, YC-IL1 strain was isolated from Mila province in Algeria and identified as Enterobacter spp.…”