Ricerc@Sapienza

DDE (2,2-bis (p-chlorophenyl)-1,1-dichloroetylene) is a very persistent and bioaccumulative pesticide and its residues are continuously found in the environment. Among the green remediation strategies for soil recovery, terrestrial Microbial Fuel Cells (MFC) are arousing great interest in scientific community. MFCs transform energy stored in the chemical bonds of organic compounds into electrical energy thanks to exo-electrogen microorganisms naturally occurring in soil, which catalyse oxidation and reduction reactions in the area between two graphite electrodes.

In this paper, a bioelectrochemical process has been developed by the combination of two membrane-less reactors equipped with an internal graphite granules counterelectrode for the perchloroethylene (PCE) removal through a reductive/oxidative sequence. In the reductive reactor, the cathodic chamber supplied the reducing power to PCE dechlorinating biomass while a rutile electrode promoted the aerobic dechlorination of the less chlorinated PCE byproducts by oxygen in situ evolution.

Polyhydroxyalkanoates (PHA) are completely biodegradable polyesters and it is well known the ability of mixed microbial cultures (MMC) to produce them by using renewable resources (e.g. waste organic streams) as feedstock. MMC-PHA production typically involves a multi-stage process including the selection of PHA-storing microorganisms from the mixed culture. This usually occurs in sequencing batch reactors (SBR) operated under dynamic feeding regime whereby microorganisms undergo periods of high (feast) and low or none (famine) concentrations of external organic substrate.

A sequential reductive-oxidative treatment was developed in this study in a continuous-flow bioelectrochemical reactor to address bioremediation of groundwater contaminated by trichloroethene (TCE) and less-chlorinated but still harmful intermediates, such as vinyl chloride. In order to optimize the anodic compartment, whereby the oxygen-driven microbial oxidation of TCE-daughter products occurs, abiotic batch experiments were performed with various anode materials poised at +1.20 V vs.

This paper focuses on microbial fuel cell (MFC) waste valorization, electricity generation and practical applications. A custom electronic analyzer dedicated to MFCs is presented. The measuring system allows to set up a complete electrical characterization of a microbial fuel cell, useful to facilitate and accurately analyze the charge and discharge phase of an MFC. Moreover, it allows power performance analysis and measurement of any kind of MFC typology, using a custom software, which automatically sets up a series of tests over a long period of time.

This paper focuses on applications and electrical valorisation of microbial fuel cells (MFCs), a promising energy harvesting technique, suitable as clean power source to supply low power devices in wireless sensor networks (WSN) for environmental and agricultural monitoring. An MFC is a bioreactor that converts energy stored in chemical bonds of organic matter into electrical energy, through a series of reactions catalysed by microorganisms. An MFC can operate as bioreactor, as bioremediator and as biosensor.

An innovative bioelectrochemical reductive/oxidative sequential process was developed and tested on a laboratory scale to obtain the complete mineralization of perchloroethylene (PCE) in a synthetic medium. The sequential bioelectrochemical process consisted of two separate tubular bioelectrochemical reactors that adopted a novel reactor configuration, avoiding the use of an ion exchange membrane to separate the anodic and cathodic chamber and reducing the cost of the reactor.

The study of the soil microbial community represents an important step in better understanding the environmental context. Therefore, biological characterisation and physicochemical integration are keys when defining contaminated sites. Fungi play a fundamental role in the soil, by providing and supporting ecological services for ecosystems and human wellbeing. In this research, 52 soil fungal taxa were isolated from in situ pilot reactors installed to a contaminated site in Czech Republic with a high concentration of hexachlorocyclohexane (HCH).

Fungi can tolerate and transform anthropogenic contaminants such as persistent organic pollutants (POPs), thanks to their metabolic and enzymatic versatility (1, 2, 3). Indeed, fungal biodegradation of POPs, e.g. DDT, has been recognized as an environmentally-friendly, feasible, integrated, cost-effective remediation biotechnology (1, 2, 3).

Several Trichoderma species can synthesize molecules of high biotechnological value, including antifungal compounds and cell-wall degrading enzymes and provide applications in mycoremediation. The saprotrophic fungal strain FBL 587, deposited in the culture collection of the Fungal Biodiversity Laboratory, Sapienza University of Rome, was isolated from Polish DDT-contaminated soils. Tolerance indices (Rt:Rc (%); T.I. (%)) were used to assess fungal tolerance to 1 mg/L DDT.