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Wastes from the oil industry represent one of the sources of soil pollution with the greatest environmental impact. Both drill cuttings and crude residues are delivered to the soil and produce severe toxic effects, mainly due to the presence of polycyclic aromatic hydrocarbons. Various bioremediation technologies have been implemented in order to restore the soil quality and the natural auto depuration capabilities, amongst them: composting, bioaugmentation and biostimulation. All of these bioremediation techniques promise to be eco-friendlier and cheaper alternatives than other approaches. In this work we have evaluated several strains of Pleurotus sp. for their effect on the bioremediation of oilcontaminated wastes and drill cuttings disposed in storage tanks or in open-air soil lots for many years. Our results suggest that combined natural attenuation mechanism and directed fungal biodegradation activities, could be promising strategies to remediate heavily petroleum polluted soils and drilling wastes both at the laboratory and in field conditions. Furthermore, we present new data that supporting Pleurotus genera as able to degrade asphaltenes, the most recalcitrant fraction of petroleum. This study proposes an approach that at the same time can treat soils contaminated with waste from drill cuttings and bottoms of crude storage tanks.

Our principal conclusions state that Lysinimonas kribbensis and Lysinimonas soli strains, actually constitute a single coherent group at 16S rRNA gene level, and Protaetiibacter intestinalis is phylogenetically and genomically consistent with the genus Leifsonia and its nomenclature must be amended.

Background: Scolopendra polymorpha (S. polymorpha) is a predatory centipede whose venom contains a multiplicity of biochemical effectors that can cause muscle damage and cumulative cell destruction in its prey. Despite previous investigations of S. polymorpha and other centipede venoms, there is a lack of information on the morphological and biochemical patterns elicited by their myotoxic effects. To elucidate these processes, this paper presents evidence of skeletal muscle damage, and alterations in key biochemical mediators that appear only after exposure to centipede venom. Methods: Venom was collected and fractionated using RP-HPLC; mouse extensor digitorum longus (EDL) muscle was exposed to whole venom and venom fractions to evaluate myotoxicity by means of creatine kinase (CK) -a muscle damage marker -activity measurements and histochemical analysis. Results: CK activity was higher in EDL muscle exposed to venom than in unexposed muscle. This increase was observed after 15 min of venom incubation, and remained stable up to 45 min. Venom-exposed EDL muscle showed signs of muscle damage including necrosis, loss of fascicular structure as well as mitochondrial accumulations and ragged red fibers (RRF), suggesting an impairment in the normal mitochondrial arrangement. Nicotinamide adenine dinucleotide (NADH) and cytochrome oxidase (COX) tests also indicate that respiratory complexes might be affected. Conclusion:Our results suggest a different biochemical composition of S. polymorpha venom, based on the different effects of four venom fractions on the cells tested, according to statistical evidence. Fractions F6 and F7 caused the most important alterations.

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