Li, Jiji (2016) Comparative behaviour of nano ZnO, bulk ZnO and ionic Zinc in marine environment and effect upon biological target organisms such as primary producers (marine algae Tetraselmis suecica and Phaeodactylum tricornutum) and filter feeder (Mediterranean mussels Mytilus galloprovincialis) chronically exposed. [Tesi di dottorato]

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Item Type: Tesi di dottorato
Resource language: English
Title: Comparative behaviour of nano ZnO, bulk ZnO and ionic Zinc in marine environment and effect upon biological target organisms such as primary producers (marine algae Tetraselmis suecica and Phaeodactylum tricornutum) and filter feeder (Mediterranean mussels Mytilus galloprovincialis) chronically exposed
Creators:
Creators
Email
Li, Jiji
feiye2214@163.com
Date: 31 March 2016
Number of Pages: 120
Institution: Università degli Studi di Napoli Federico II
Department: Agraria
Scuola di dottorato: Scienze agrarie e agro-alimentari
Dottorato: Scienze e tecnologie delle produzioni agro-alimentari
Ciclo di dottorato: 28
Coordinatore del Corso di dottorato:
nome
email
Barbieri, Giancarlo
barbieri@unina.it
Tutor:
nome
email
Fogliano, Vincenzo
UNSPECIFIED
Manzo, Sonia
UNSPECIFIED
Date: 31 March 2016
Number of Pages: 120
Keywords: Zinc oxide nanoparticles, mussel, phytoplancton
Settori scientifico-disciplinari del MIUR: Area 07 - Scienze agrarie e veterinarie > AGR/15 - Scienze e tecnologie alimentari
Date Deposited: 08 Apr 2016 09:29
Last Modified: 02 Nov 2016 12:59
URI: http://www.fedoa.unina.it/id/eprint/10974

Collection description

Zinc oxide nanoparticles (ZnO NPs), one among the most widely used metal oxide nanomaterias, has unique properties, such as optoelectronic property, UV emission, transparent conductivity, piezoelectricity, UV absorption and reflection, those make ZnO NPs to be currently used in a broad range of products. Such widespread and expanding production and use increase the potential for their release into the environment, in US, Euorpe, and China. With the vast releasing of ZnO NPs, the ecotoxic risk had drawn much research interest in the last decades. The aquatic ecosystem is the final destination of the released ZnO NPs and the coastal seawaters takes into the most of discharge. At least three distinct mechanisms of the toxic action of ZnO NPs, released toxic Zn2+ effect, surface interactions with media may produce toxic substance were report, and photo-induced toxicity, were reported. Based on the published literatures reviewing, several research points on ecotoxicity of ZnO NPs towards algae and mussel in marine environment were still unexplored and some represent aims of this study. • ZnO NPs could have a specific behavior and effect in diverse marine seawaters. To this aim the full characterization of ZnO NP dissolution, aggregation, and sedimentation once dispersed into a standard Artificial Sea Water (ASW) and a Reconstituted Sea Water (RSW) from East China Sea was performed. • The ecotoxicity of ZnO NPs upon a green alga and a diatom would be different. To assess the diverse toxicity upon different algae, growth inhibition algal assays were performed. Additionally, to verify the hypothesis about the role of nano size in the overall toxicity, ZnO bulk, and Zn salt toxicity were assessed as well. • ZnO NP toxicity towards mussels under a chronic exposure could be shown by Zn bioaccumulation, tissue damages, and transcription of apoptosis and antioxidation-related genes. The hypothesis that nano size plays an important role in its toxicity was also considered together with the all previous ones for mussel M. galloprovincialis. The obtained results answered to the all hypotheses. Behaviors of ZnO NPs and bulk in different artificial seawater were observed indicating that the primary size of ZnO in suspensions could affect the aggregating rate in higher concentration. The behaviors of ZnO NPs dispersed into ASW and RSW have similar changing trends with some slight differences. Comparative toxicity of ZnO NPs, bulk, and Zn salt towards marine algae indicated that the nano size plays a key role in the overall ZnO toxicity. Zn bioaccumulation and histological damages were observed for mussel exposed to ZnO NPs, bulk, and Zn salt. Pristine ZnO particle size influences the overall toxicity and the rank was represented by three levels of injury (in gill, digestive gland, and gonad): low for bulk; medium for NPs and high for salts. Ecotoxicity of ZnO NPs in mussel revealed by transcription of apoptosis and antioxidation-related genes indicated that active response to ZnO NP exposure which induced DNA damage and oxidant injury contributing to the overall toxicity. In conclusion, zinc oxide nanoparticles induced ecotoxicolgical stress to two algae and a mussel in marine environment that were related to the ROS-induced property.

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