Producción de lacasa extracelular y degradación de compuestos fenólicos mediante un aislado de aguas residuales de almazara

Olive mill wastewater (OMWW) presents a challenge to the control of effluents due to the presence of a high organic load, antimicrobial agents (monomeric-polymeric phenols, volatile acids, polyalcohols, and tannins), salinity and acidity. In this study, the production of extracellular laccase, monomeric or polymeric phenol, from an OMWW isolate based on its ability to biodegrade phenols and gallic acid as a model of phenolic compounds in OMWW was investigated. Phylogenetic analysis of the 16S RNA gene sequences identified the bacterial isolate (Acinetobacter REY) as being closest to Acinetobacter pittii. This isolate exhibited a constitutive production of extracellular laccase with an activity of 1.5 and 1.3 U ml/L when supplemented with the inducers CuSO4 and CuSO4+phenols, respectively. Batch experiments containing minimal media supplemented with phenols or gallic acid as the sole carbon and energy source were performed in order to characterize their phenolic biodegradability. Acinetobacter REY was capable of biodegrading up to 200 mg/L of phenols and gallic acid both after 10 h and 72 h, respectively.Las aguas residuales de almazara (OMWW) presentan un desafío a los efluentes debido a la presencia de una carga orgánica alta, agentes antimicrobianos (fenoles monoméricos y poliméricos, ácidos volátiles, polialcoholes y taninos), salinidad y acidez. En este estudio, se investigó la producción de lacasa extracelular a partir de un aislado de OMWW basado en su capacidad para biodegradar fenol y ácido gálico como modelo de compuestos fenólicos en OMWW. El análisis filogenético de las secuencias del gen de ARN 16S identifico el aislado bacteriano (Acinetobacter REY) como el más cercano a Acinetobacter pittii. Este aislado exhibió producción constitutiva de lacasa extracelular con una actividad de 1.5 y 1.3 U mL/L cuando se suplemento con los inductores CuSO4 y CuSO4 + fenol, respectivamente. Se realizaron experimentos en lotes que contenían medios mínimos suplementados con fenol o acido gálico como la única fuente de carbono y energía con el fin de caracterizar su biodegradabilidad fenólica. Acinetobacter REY fue capaz de biodegradar hasta 200 mg/L de fenol y acido gálico después de 10 y 72 h, respectivamente

Antibiofilm, Antifouling, and Anticorrosive Biomaterials and Nanomaterials for Marine Applications

Formation of biofilms is one of the most serious problems affecting the integrity of marine structures both onshore and offshore. These biofilms are the key reasons for fouling of marine structures. Biofilm and biofouling cause severe economic loss to the marine industry. It has been estimated that around 10% of fuel is additionally spent when the hull of ship is affected by fouling. However, the prevention and control treatments for biofilms and biofouling of marine structures often involve toxic materials which pose severe threat to the marine environment and are strictly regulated by international maritime conventions. In this context, biomaterials for the treatment of biofilms, fouling, and corrosion of marine structures assume much significance. In recent years, due to the technological advancements, various nanomaterials and nanostructures have revolutionized many of the biological applications including antibiofilm, antifouling, and anticorrosive applications in marine environment. Many of the biomaterials such as furanones and some polypeptides are found to have antibiofilm, antifouling, and anticorrosive potentials. Many of the nanomaterials such as metal (titanium, silver, zinc, copper, etc.) nanoparticles, nanocomposites, bioinspired nanomaterials, and metallic nanotubes were found to exhibit antifouling and anticorrosive applications in marine environment. Both biomaterials and nanomaterials have been used in the control and prevention of biofilms, biofouling, and corrosion in marine structures. In recent years, the biomaterials and nanomaterials were also characterized to have the ability to inhibit bacterial quorum sensing and thereby control biofilm formation, biofouling, and corrosion in marine structures. This chapter would provide an overview of the biomaterials from diverse sources and various category of nanomaterials for their use in antibiofilm, antifouling, and anticorrosion treatments with special reference to marine applications