The biodegradation of 1,3-dichlorobenzene by an adapted strain Bacillus cereus PF-11 derived from town-gas industrial effluent

Halotolerant bacteria in the São Paulo Zoo composting process and their hydrolases and bioproducts

Halophilic microorganisms are able to grow in the presence of salt and are also excellent source of enzymes and biotechnological products, such as exopolysaccharides (EPSs) and polyhydroxyalkanoates (PHAs). Salt-tolerant bacteria were screened in the Organic Composting Production Unit (OCPU) of São Paulo Zoological Park Foundation, which processes 4 ton/day of organic residues including plant matter from the Atlantic Rain Forest, animal manure and carcasses and mud from water treatment. Among the screened microorganisms, eight halotolerant bacteria grew at NaCl concentrations up to 4 M. These cultures were classified based on phylogenetic characteristics and comparative partial 16S rRNA gene sequence analysis as belonging to the genera Staphylococcus, Bacillus and Brevibacterium. The results of this study describe the ability of these halotolerant bacteria to produce some classes of hydrolases, namely, lipases, proteases, amylases and cellulases, and biopolymers. The strain characterized as of Brevibacterium avium presented cellulase and amylase activities up to 4 M NaCl and also produced EPSs and PHAs. These results indicate the biotechnological potential of certain microorganisms recovered from the composting process, including halotolerant species, which have the ability to produce enzymes and biopolymers, offering new perspectives for environmental and industrial applications.

An anti-biodegradable hydrophobic sulfonate-based acrylamide copolymer containing 2,4-dichlorophenoxy for enhanced oil recovery

We report the synthesis of a novel hydrophobic sulfonate-based acrylamide copolymer which exhibits remarkable water solubility, excellent resistance to biodegradability, and superior ability to enhance oil recovery.

Microbial community profiling and characterization of some heterotrophic bacterial isolates from river waters and shallow groundwater wells along the Rouge River, southeast Michigan

This study was conducted to elucidate microbiological characteristics of river water and groundwater communities in order to improve our conceptual and predictive understanding of river and groundwater ecosystem processes, functioning and management. Rouge River bacterial communities from shallow groundwater and river water were screened using Biolog Ecoplates, which test for oxidation of selected carbon sources and by culturing heterotrophic bacteria. The isolates cultured from the samples were also characterized using the 16SrRNA gene-based approach. The patterns of utilization of the groups of carbon substrates by the microbial communities revealed differences between river water and groundwater samples. Carbohydrates, polymers, carboxylic acids and amino acids were highly utilized by the microbial communities in the river samples, while carbohydrates, polymers, amino acids and phenolic compounds were metabolized in the groundwater samples. Sequence comparison results showed that the most prevalent phylum in all sites was the Firmicutes (low G+C, mostly gram-positive bacteria). The dominant isolates from this phylum were similar to Bacillus spp., (98% nucleotide identity), which represented approximately 62% of the total number of unique isolates. Also prevalent were the gamma-Proteobacteria, which were dominated by 16S rRNA sequences 98-99% similar to that of Pseudomonas spp. The observed profile of carbon sources metabolized reflected the catabolic potential of the river water and groundwater community. Many of the isolates recovered have been known to metabolize several organic substrates, and may have potential use in remediation organic contaminants from the Rouge River. Direct incubation water samples in Biolog Ecoplates produced patterns of metabolic response useful in the classification and characterization of river water and groundwater microbial communities. Heterotrophic bacteria isolated from the sites may play important roles in the fate of many organic and inorganic contaminants from the Rouge River, although future studies are needed to understand their response to these contaminants.

By-side impurities in chloronaphthalene mixtures of the Halowax series: all 12 chlorobenzenes

Total chlorobenzene content of the Halowax mixtures ranged from 1100 to 9800 ng/g. A lower chlorinated Halowax 1031 and 1000 were a several times more contaminated with chlorobenzenes than higher chlorinated Halowax 1001, 1099, 1013, 1014, or 1051. Depending on the type of the Halowax mixture the most contributing amongst of chlorobenzene homologue groups were di-, tetra-, penta-, and hexa-CBz. A dominance and specific profile of 1,4-DiCBz, PeCBz, and HCBz were characteristic to Halowax 1001, 1099, 1013, 1014, and 1051, while for other formulation the CBzs profile varied, and 1,2,3,4-TeCBz (Halowax 1031) and 1,4-DiCBz (Halowax 1000) predominated. A steric hindrance effect seems to direct a preferential by-side formation of 1,4-DiCBz and further also of PeCBz and HCBz due to relatively elevated temperature as well as duration time of synthesis for five most chlorinated (49-70 Cl%) chloronaphthalene Halowax formulations.