Phthalates are synthesized in massive amounts to produce various plastics and have become widespread in environments following their release as a result of extensive usage and production. This has been of an environmental concern because phthalates are hepatotoxic, teratogenic, and carcinogenic by nature. Numerous studies indicated that phthalates can be degraded by bacteria and fungi under aerobic, anoxic, and anaerobic conditions. This paper gives a review on the biodegradation of phthalates and includes the following aspects: (1) the relationship between the chemical structure of phthalates and their biodegradability, (2) the biodegradation of phthalates by pure/mixed cultures, (3) the biodegradation of phthalates under various environments, and (4) the biodegradation pathways of phthalates.

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approach involving fi xing HPW into a polyvinylpyrrolidone (PVP) and polyethersulfones (PES) matrix. A high proton conductivity of 0.066 S cm -1 is achieved at 60 °C with fully hydrated conditions when the HPW content is 30 wt%, which is very competitive with that of Nafi on115 under the same test conditions. Most signifi cantly, the proton conductivity of PES/PVP-HPW is remarkably stable under a continuous fl ow of deionized (DI) water on both sides of the electrolyte membrane for a test period of more than 500 h. A PEMFC single cell based on the PES/PVP-HPW membrane exhibits impressive performance with a maximum power density of 618 mW cm −2 at 50 °C in H 2 /O 2 , and shows no obvious loss within 500 h. This hybrid PES/PVP-HPW holds great potential applications as a novel PEM due to the comparable performance and signifi cantly reduced cost compared to Nafi on.The synthesis and formation of the HPW self-anchored PES/PVP-HPW PEM through a one-step route was given in Scheme 1 . PVP, PES (mass ratio PVP:PES = 90:10) and HPW with desired content (e.g., 10 wt%, 20 wt%, or 30 wt%) were mixed in N , N -dimethylformamide (DMF) and stirred to form a transparent and homogeneous casting solution. This solution was cast onto a glass plate and dried at 343 K for 24 h to remove the solvent and obtain a PES/PVP-HPW. In the hybrid PEM, PVP that contains an N-heterocycle plays a key role in the formation of membrane and offers self-anchored site for HPW. The self-anchored HPW in the membrane acts as the sole proton conductor and cross-linking agent. PES was added to the membrane as a skeleton, to improve membrane formation and enhance the mechanical strength of the hybrid membrane, which could be replaced with other engineering plastics, for example, polysulfone, polyvinylidene fl uoride, or polyarylsulfone. Figure 1 a-c shows a photograph and cross-sectional scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of the as-prepared PES/PVP-HPW. The photograph shown in Figure 1 a shows that the membrane was highly transparent and fl exible. The SEM image of the PES/PVP-HPW membrane cross-section exhibited no obvious phase separation, which indicates that these membranes were homogeneous (Figure 1 b). The energy-dispersive X-ray spectroscopy (EDS) tungsten (W) map (inset of Figure 1 b) indicates that the element W (green spots) was homogeneously dispersed in the membrane, which was further demonstrated by the TEM image of the hybrid membrane (Figure 1 c). The average HPW nanoparticle size was determined to be ca. 2.2 nm with a narrow distribution (Supporting Information Figure S1), which was about two HPW molecule size. [ 8 ] The X-ray diffraction (XRD) patterns of the hybrid membrane (see Supporting Information Figure S2) contained no characteristic diffraction peaks The development of proton exchange membranes (PEMs) with improved performance is critical for advancing electrochemical energy devices such as fuel cells and water electrolyzers. [ 1 ] However, the large-scale application of state-of...

Polluted urban river sediments could be a sink of persistent and toxic polychlorinated biphenyls (PCBs) in urban areas and provide desired growth niches for organohalide-respiring bacteria (OHRB). In this study, microcosms were set up with surface sediments of nationwide polluted urban rivers in China, of which 164 cultures could dechlorinate tetrachloroethene (PCE) to dichloroethenes (DCEs) and to vinyl chloride and/or ethene. Further in vivo tests showed extensive PCB dechlorination with different pathways in 135 PCE pregrown cultures. Taking reductive dechlorination of PCB180 (2345-245-CB) as an example, 121 and 14 cultures preferentially removed flanked para-and meta-chlorines, respectively. Strikingly, all in vitro assays with the 135 PCE pregrown cultures showed identical PCB dechlorination pathways with their living cultures, implying the involvement of bifunctional reductive dehalogenases (RDases) to dechlorinate both PCBs and PCE. Further 16S rRNA and RDase gene-based analyses, together with enantioselective dechlorination of chiral PCBs, suggested that Dehalococcoides and Dehalogenimonas in the 135 cultures largely employed distinctively different novel bifunctional RDases to catalyze PCB/PCE dechlorination. Quantitative assessment of the community assembly process with the modified stochasticity ratio (MST) indicated three different stages in enrichment of OHRB. The second stage, as the only one controlled by stochastic processes (MST > 0.5), required extra attention in monitoring community successional patterns to minimize stochastic variance for enriching the PCB/PCEdechlorinating OHRB.