Status of Fishery Discards and By-Products in Greece and Potential Valorization Scenarios towards a National Exploitation Master Plan.

The valorization of aquaculture/fishery processing by-products, as well as unavoidable/unwanted catches and discards in Greece, is currently an underutilized activity despite the fact that there are several best practices in Northern Europe and overseas. One of the main challenges is to determine whether the available quantities for processing are sufficient to warrant the valorization of discards and fish side streams. This is the first attempt to systematically record and analyze the available quantities of fish by-products and discards in Greece spatially and temporally in an effort to create a national exploitation Master Plan for the valorization of this unavoidable and unwanted biomass. A thorough survey conducted within the VIOAXIOPIO project unveiled a substantial biomass of around 19,000 tonnes annually that could be harnessed for valorization. Furthermore, the production of various High-Added-Value Biomolecules (HAVBs) was investigated and experimental trials were conducted to assess the potential yields, with the collected data used to formulate four valorization scenarios.

Identification of Marine Biotechnology Value Chains with High Potential in the Northern Mediterranean Region.

Marine (blue) biotechnology is an emerging field enabling the valorization of new products and processes with massive potential for innovation and economic growth. In the Mediterranean region, this innovation potential is not exploited as well as in other European regions due to a lack of a clear identification of the different value chains and the high fragmentation of business innovation initiatives. As a result, several opportunities to create an innovative society are being missed. To address this problem, eight Northern Mediterranean countries (Croatia, France, Greece, Italy, Montenegro, Portugal, Slovenia and Spain) established five national blue biotechnology hubs to identify and address the bottlenecks that prevent the development of marine biotechnology in the region. Following a three-step approach (1. Analysis: setting the scene; 2. Transfer: identification of promising value chains; 3. Capitalization: community creation), we identified the three value chains that are most promising for the Northern Mediterranean region: algae production for added-value compounds, integrated multi-trophic aquaculture (IMTA) and valorization aquaculture/fisheries/processing by-products, unavoidable/unwanted catches and discards. The potential for the development and the technical and non-technical skills that are necessary to advance in this exciting field were identified through several stakeholder events which provided valuable insight and feedback that should be addressed for marine biotechnology in the Northern Mediterranean region to reach its full potential.

High-Resolution Melting (HRM) Analysis for Rapid Molecular Identification of Sparidae Species in the Greek Fish Market.

The red porgy (Pagrus pagrus) and the common dentex (Dentex dentex) are Sparidae species of high commercial value, traded in the Greek market. In some cases, fish species identification from Greek fisheries is difficult for the consumer due to the strong morphological similarities with their imported counterparts or closely related species such as Pagrus major, Pagrus caeroleustictus, Dentex gibbosus and Pagellus erythrinus, especially when specimens are frozen, filleted or cooked. Techniques based on DNA sequencing, such as COI barcoding, accurately identify species substitution incidents; however, they are time consuming and expensive. In this study, regions of mtDNA were analyzed with RFLPs, multiplex PCR and HRM in order to develop a rapid method for species identification within the Sparidae family. HRM analysis of a 113 bp region of cytb and/or a 156 bp region of 16s could discriminate raw or cooked samples of P. pagrus and D. dentex from the aforementioned closely related species and P. pagrus specimens sampled in the Mediterranean Sea when compared to those fished in the eastern Atlantic. HRM analysis exhibited high accuracy and repeatability, revealing incidents of mislabeling. Multiple samples can be analyzed within three hours, rendering this method a useful tool in fish fraud monitoring.

Development of Multiplex PCR and Melt-Curve Analysis for the Molecular Identification of Four Species of the Mullidae Family, Available in the Market.

The authentication of food products and the verification of their identity are of major importance for consumers. Food fraud through mislabeling is an illegal practice consisting of the substitution of an expensive food product by a relatively cheaper one, misleading false labelling of their origin and adulteration in processed or frozen products. This issue is particularly of high importance concerning fish and seafood, which are easily adulterated primarily due to difficult morphological identification. Fish species of the Mullidae family are considered among the most high-valued seafood products traded in Greece and Eastern Mediterranean in general, in terms of the price and demand. Specifically, the red mullet (Mullus barbatus) and the striped red mullet (Mullus surmuletus) are both indigenous in the Aegean (FAO Division 37.3.1) and the Ionian (FAO Division 37.2.2) Seas, with high levels of consumers' preferences. However, they could be easily adulterated or misidentified by the invasive Aegean Sea Lessepsian migrator goldband goatfish (Upeneus moluccensis) as well as by the imported West African goatfish (Pseudupeneus prayensis). Keeping this in mind, we designed two novel, time-saving and easy-to-apply multiplex PCR assays and one multiple Melt-Curve analysis real-time PCR for the identification of these four species. These methodologies are based on species-specific primers targeting single nucleotide polymorphisms (SNPs) detected via sequencing analysis of the mitochondrial cytochrome C oxidase subunit I (CO1) and of the cytochrome b (CYTB) genes in newly collected individuals, with additional comparison with congeneric and conspecific haplotypes obtained from the GenBank database. Both methodologies, targeting CO1 or CYTB, utilize one common and four diagnostic primers, producing amplicons of different length that are easily and reliably separated on agarose gel electrophoresis, yielding a single clear band of diagnostic size for each species or a certain Melt-Curve profile. The applicability of this cost-effective and fast methodology was tested in 328 collected specimens, including 10 cooked samples obtained from restaurants. In the vast majority (327 out of the 328) of the specimens tested, one single band was produced, in agreement with the expected products with a single exception a M. barbatus sample that was identified as M. surmuletus, the identity of which was confirmed using sequencing, indicating erroneous morphological identification. The developed methodologies are expected to contribute to the detection of commercial fraud in fish authentication.

A multi-criteria assessment of the implementation of innovative technologies to achieve different levels of microplastics and macroplastics reduction.

This paper proposes and applies a multicriteria decision analysis framework tailored to assess measures for reducing the concentration of microplastics and macroplastics in seas, by implementing ground-breaking clean-up technologies and addressing different types of pollutant sources. Environmental, socio-economic and financial impacts are considered to provide a ranking of these measures for better-informed decision making. The data required to evaluate the performance of the technologies in different locations and scales are analyzed to understand the consequences of the different measures in terms of plastic pathways and sites, and the amounts accumulated, using innovative simulation models. The framework is applied to the Mediterranean Sea, providing insights for designing measures to respond to the challenges of cleaning seas and fulfill the EU marine strategy. The results for the best ranked alternatives show that dealing with microplastics is much more expensive (by one order of magnitude) than dealing with macroplastics.

A multi-criteria assessment of policies to achieve the objectives of the EU marine litter strategy.

This paper proposes and assesses policy options to achieve the objectives of the EU marine litter strategy, based on the existing EU legislation. A group of experts and stakeholders was involved through a multi-staged workshop organized to generate the information to assess the contribution of the policies to the set of objectives, as well as the relative importance of the objectives, on qualitative scales. The ELECTRE TRI multi-criteria decision analysis method was used to rate the policies, which were subsequently ranked. Per the results, all policies deserve to be considered, even when the more pessimistic assessments (33rd percentile) are used. Revising the Urban Wastewater Treatment Directive, setting legislative targets on marine litter and ensure they are fully monitored, and funding proven clean-up technologies were deemed to be the most potentially impactful policies. The remaining policies assessed can nevertheless play an important role in complementing the higher-ranked policies.

Adoption and diffusion of marine litter clean-up technologies across European seas: Legal, institutional and financial drivers and barriers.

This study reviews existing legal, institutional and policy tools and frameworks, relevant to the introduction and adoption of new marine litter clean-up technologies in two regional European seas, the Mediterranean and the Baltic. A combination of desk studies in six countries bordering the Baltic (Estonia, Germany, Sweden) and the Mediterranean (Greece, Italy, Tunisia), and interviews with experts and stakeholders, is used to identify key drivers and barriers to the adoption and diffusion of marine litter technologies. The main conclusion of the study is that the most influential pieces of legislation relevant to marine litter management are top-down EU policies, often forming the basis of regional and national plans. Moreover, the study finds that several drivers of marine litter technologies may at the same time be critical barriers. These factors include public awareness, consumer behaviour, enforcement of legislation, and the rise of SMEs engaged in recycling and eco-labelling of marine litter.