Bioremediation of soil contaminated with pentachlorophenol by Anthracophyllum discolor and its effect on soil microbial community.

Bioaugmentation is a promising technology to clean up sites contaminated with recalcitrant chemicals. White-rot fungi have proven to be effective in the degradation of pentachlorophenol. Here, we report the bioremediation of soil contaminated with pentachlorophenol (PCP) by Anthracophyllum discolor and its impact on the soil microbial community. In this study three types of microcosms were established: fresh soil (C(0)), fresh soil plus wheat straw (WS(0)) and, fresh soil plus wheat straw inoculated with A. discolor (WSAD(0)). Additionally, similar treatments and a control of sterile soil spiked with PCP (C(250), WS(250) and WSAD(250)) were used to evaluate the remediation and adsorption of PCP. The PCP removal, total microbial activity, and enzymatic activities were evaluated. This study also investigated the structure of soil microbial community by denaturing gradient gel electrophoresis (DGGE), identifying some of the dominant bacterial and fungal species. The results showed that PCP was effectively degraded in soils by A. discolor and by indigenous soil microorganisms. The addition of wheat straw increased the PCP degradation and enzymatic activities. Only laccase activity was negatively affected by PCP contamination. The PCP degradation was associated with changes in microbial communities, mainly stimulation of members of bacterial phylum Proteobacteria (Xanthomonadaceae, Burkholderiaceae and Enterobacteriaceae), and fungal phylum Ascomycota and Basidiomycota. This study shows the ability of A. discolor to degrade PCP from contaminated soil, and demonstrates that agricultural residues, such as wheat straw, can be used as growth substrate by microorganisms in PCP-contaminated soil, demonstrating a great potential of autochthonous microorganisms for soil remediation.

Cea M ，Jorquera M ，Rubilar O ，Langer H ，Tortella G ，Diez MC ... -  《-》

Bioremediation of a Chilean Andisol contaminated with pentachlorophenol (PCP) by solid substrate cultures of white-rot fungi.

Rubilar O ，Tortella G ，Cea M ，Acevedo F ，Bustamante M ，Gianfreda L ，Diez MC ... -  《-》

Growth substrate selection and biodegradation of PCP by New Zealand white-rot fungi.

Walter M ，Boul L ，Chong R ，Ford C ... -  《JOURNAL OF ENVIRONMENTAL MANAGEMENT》

Response of compost maturity and microbial community composition to pentachlorophenol (PCP)-contaminated soil during composting.

Two composting piles were prepared by adding to a mixture of rice straw, vegetables and bran: (i) raw soil free from pentachlorophenol (PCP) contamination (pile A) and (ii) PCP-contaminated soil (pile B). It was shown by the results that compost maturity characterized by water soluble carbon (WSC), TOC/TN ratio, germination index (GI) and dehydrogenase activity (DA) was significantly affected by PCP exposure, which resulted in an inferior degree of maturity for pile B. DGGE analysis revealed an inhibited effect of PCP on compost microbial abundance. The bacteria community shifts were mainly consistent with composting factors such as temperature, pH, moisture content and substrates. By contrast, the fungal communities were more sensitive to PCP contamination due to the significant correlation between fungal community shifts and PCP removal. Therefore, the different microbial community compositions for properly evaluating the degree of maturity and PCP contamination were suggested.

Zeng G ，Yu Z ，Chen Y ，Zhang J ，Li H ，Yu M ，Zhao M ... -  《-》

Chlorophenol degradation in soil columns inoculated with Anthracophyllum discolor immobilized on wheat grains.

The white-rot fungus Anthracophyllum discolor immobilized on wheat grains was evaluated for chlorophenol (2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol) degradation in allophanic soil columns activated by acidification. Columns without inoculation were used as the control to evaluate the adsorption capacity of the soil columns. The chlorophenols were removed efficiently in soil columns by both adsorption and degradation processes. In inoculated soil columns, 2,4-dichlorophenol was highly degraded and this degradation is associated with a high production of manganese peroxidase. 2,4,6-trichlorophenol was degraded to a lesser extent compared with 2,4-dichlorophenol. Pentachlorophenol was first removed by adsorption and then through degradation by the fungus. Manganese peroxidase activity was lowest when the column was fed with pentachlorophenol and highest when the column was fed with 2,4-dichlorophenol. Laccase was also produced by the fungus but to a lesser degree.

Diez MC ，Gallardo F ，Tortella G ，Rubilar O ，Navia R ，Bornhardt C ... -  《-》