Macellaro, Gemma (2014) DEVELOPMENT OF BIOSYSTEMS FOR THE DETECTION AND DEGRADATION OF ENDOCRINE DISRUPTING CHEMICALS (EDCs). [Tesi di dottorato]

Anteprima

Testo Macellaro_Gemma_26°_ciclo.pdf Download (6MB) | Anteprima

Abstract

In recent years, a large number of materials and compounds have been produced without adequate knowledge on their interaction with the environment and of their influence on human health. This resulted in a continuous pollution by a wide array of hazardous chemicals with different structures and toxicity levels. These chemicals have deleterious effects on the reproductive systems of various animals, including humans. This dangerous situation has required the formulation of strict environmental regulations in order to reduce the emissions and to ban the production of the incriminated compounds. Furthermore, the development of news efficient and cost-effective technologies became necessary to resolve the problems of effluents treatment. To this aim physical and chemical processing were initially tested, but they resulted expensive and may generate a large volume of sludge. In the last years, biological wastewater treatments have represented an attractive alternative as they could be cost-effective and environmentally friendly. For these reasons, many biodegradation processes were encouraged to resolve this problem. In this context, the present research explores various methods for biodegradation of a class of above-mentioned chemicals: endocrine disrupting chemicals (EDCs). EDCs are able to interfere with endocrine function in a number of wildlife species, leading to adverse effects particularly in relation to reproduction. Two kinds of processes have been specifically analysed: • oxidation of these compounds using laccase enzymes from the white-rot fungus Pleurotus ostreatus; • biodegradation process based on the use of different mushrooms. As regard as laccases, their degradability performances, against each EDC, were studied in the presence and in the absence of mediators. Two different mediators were chosen, a natural and synthetic one. Mediator addition enhanced laccase activity, favouring oxidation of recalcitrant xenobiotics. Degradation capabilities of best enzyme were also studied against EDCs mixture. In order to increase oxidative capabilities of selected enzyme, its immobilization on glass beads was performed. As concern as various mushrooms, white-rot and aquatic fungi were chosen to analyse their degradative capabilities towards each xenobiotic. Moreover, to mimic real condition, their capabilities were studied also in the presence of EDCs mixture. In the end, considering the great amount of these micropollutants in the environment, a screening of mushrooms able to growth on EDCs was performed using ground sample.

Downloads

Actions (login required)

Modifica documento