Bioaccumulation of some Heavy Metals in Red mullet (Mullus barbatus) and Common pandora (Pagellus erythrinus) in Zliten Coast, Libya

Highlight Investigated in heavy metal bio-accumulation in red mullet (Mullus barbatus) and Common pandora (Pagellus erythrinus) collected in Zliten Coast, Libya.Based on the samples collected, the muscle tissue of fish species may be considered suitable for human consumption.The metal concentration levels observed were in range of acceptable limits proposed by regulations of WHO and FAO.AbstractThe current study aimed to determine the heavy metal concentration like as copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd) and mercury (Hg) in the liver, gills, gonad and muscles in two fish species (red mullet (Mullus barbatus), and common Pandora (Pagellus erythrinus) collected from the Zliten coast in Libya. The levels of heavy metals were determined by using an atomic absorption spectrophotometer (AAS). The results showed that the concentration of heavy metals in the sampled fishes less than the permissible limits for human consumption. In addition, the bioaccumulation for Cu, Pb, Cd, and Hg by both fish species was: liver >gills > gonads > muscles, while Zn follows the sequence: gonads > liver > gills > muscles.

A Rapid Method for the Identification of Fresh and Processed Pagellus erythrinus Species against Frauds

The commercialization of porgies or seabreams of the family Sparidae has greatly increased in the last decade, and some valuable species have become subject to seafood substitution. DNA regions currently used for fish species identification in fresh and processed products belong to the mitochondrial (mt) genes cytochrome b (Cytb), cytochrome c oxidase I (COI), 16S and 12S. However, these markers amplify for fragments with lower divergence within and between some species, failing to provide informative barcodes. We adopted comparative mitogenomics, through the analysis of complete mtDNA sequences, as a compatible approach toward studying new barcoding markers. The intent is to develop a specific and rapid assay for the identification of the common pandora Pagellus erythrinus, a sparid species frequently subject to fraudulent replacement. The genetic diversity analysis (Hamming distance, p-genetic distance, gene-by-gene sequence variability) between 16 sparid mtDNA genomes highlighted the discriminating potential of a 291 bp NAD2 gene fragment. A pair of species-specific primers were successfully designed and tested by end-point and real-time PCR, achieving amplification only in P. erythrinus among several fish species. The use of the NAD2 barcoding marker provides a rapid presence/absence method for the identification of P. erythrinus.

Antibiotic resistance of bacteria isolated from Pagellus erythrinus microplastics and public health

Microplastics (MPs) are widespread in the aquatic environmental due to anthropogenic pollution and are ingested indifferently by fishes that confuse them with food. In aquatic environment, mechanical stress, UV radiations, chemical and biological actions cause a constant degradation and breakdown of plastic objects into smaller fragments. Mediterranean Sea is characterized by the highest densities of plastics in the world being a closed basin with a complex hydrodynamics. The aim of this work is to evidence the occurrence of microbial adhesions on MPs found in edible Pagellus erythrinus (Linnaeus, 1758) bought in local Sicilian supermarkets and therefore highlight the potential role of microplastics in conveying antibiotic resistance by ingestion of food by humans. The composition and structural-morphological properties of MPs found in the excised gastrointestinal tract (GIT) and gills are identified using different techniques. In particular, microparticles of different nature (plastics, organic components, cellulose-based materials) have been determined following specific Raman signals on a large spectral range (300-3500 cm-1). The Pagellus was dissected, open longitudinally, within a sterile glass Petri dish. The components deemed exogenous to the normal structure of the gills and GIT were collected. Optical microscopy images showed that both the GIT and the gill of Pagellus erythrinus contain MPs of different colors (black, dark blu) and mainly with a fibrous shape. At the moment, microbial assays show the adhesion of Citrobacter and E. coli in some fibers extracted by gills while Vibrio spp was mainly detected in the fibers present in GIT. Bacterial isolates were screened for susceptibility to antibiotics using the Kirby-Bauer test, choosing the molecules most used in human therapy. The results obtained suggest that plastics may contribute to the spread of multiple antibiotic resistance in marine environments underline the relevance of future studies on this topic. Key messages Plastics can serve as vectors for the spread of multiple resistances to antibiotics across marine environments. Further studies on possible vehicles of multidrug-resistant germs carried by food of various kinds are desirable.

Genetic and Bio-Ecologic Characteristics of Common Pandora Pagellus erythrinus from the Eastern Mediterranean Coast of Turkey for the Ecosystem-Based Fishery Management

Genetic structure and growth characteristics of common pandora Pagellus erythrinus populations collected from the Iskenderun, Mersin and Antalya Bays were revealed through D-loop sequencing of mtDNA and length-weight and age-length relationships. While the highest value of genetic diversity was obtained in the Mersin population (0.0024), the lowest value was in Iskenderun population (0.0006). A total of 9 haplotypes was found and mean haplotype diversity was found 0.7485. The highest genetic divergence was observed between the Mersin and Iskenderun Bay populations (0.0206), whereas the Iskenderun and Antalya Bay populations had the least genetic divergence (0.0165). BioMorphv3 was used for determining the length-weight and age-length relationships. The length-weight relationships for all individuals of Iskenderun, Mersin and Antalya populations were estimated as W=0.0693 x L 2.3887 (r=0.9456), W=0.0786 x L 2.3338 (r=0.9473) and W=0.0693 x L 2.3887 (r=0.9542), respectively. The von Bertalanffy growth parameters for all individuals of Iskenderun, Mersin and Antalya populations were calculated as Lt=39.22 [1 - e0.210(t+0.32)], Lt=50.48 [1-e0.120(t+2.76)], Lt=38.08 [1-e 0.158(t+0.48)], respectively.

Biological aspects of two coexisting native and non-native fish species in the Aegean Sea: Pagellus erythrinus vs. Nemipterus randalli

Nowadays, the Mediterranean is a hotspot of biodiversity, characterized by changes in fish communities due to invasions. These invasions, mainly occurring through the entrance of species through the Suez Canal, a process called Lessepsian migration, has been increasing in the last 40 years. It is reported that, in Turkish seas, where 512 fish species are found, are 75 Lessepsian species. However, knowledge about the impact of Lessepsian species on native species is insufficient. This study aims to determine the bio-ecological characteristics and food interactions of a native Pagellus erythrinus and non-native Nemipterus randalli distributed in the Gökova Bay.In the monthly sampling survey, carried out between January 2016 and December 2016, 1698 N. randalli and 945 P. erythrinus individuals were collected. Length, weight, age, sex distributions and ratios, length-age, weight-age, length-weight relationships, condition factors, stomach contents and reproduction periods were examined to determine the interaction between species. According to results, the life span of P. erythrinus is longer than N. randalli in the Gökova Bay. Nevertheless, N. randalli grows faster than P. erythrinus. Reproduction periods of both two species show similarities. Food competition between species is found to be significantly high. Results of condition factors exhibit that N. randalli shows an increased ability to exploit the available food sources. Pagellus erythrinus displays strategies such as: early maturation, short reproduction period, reproduction in the deeper waters and batch spawning, to compete with N. randalli. With the invasive characteristics of N. randalli established a successful population in the Gökova Bay.

Length-weight relationship and growth parameters of the commercial fish Pagellus erythrinus (Linnaeus, 1758) (Actinopterygii: Sparidae) from northern and southern Tunisia

Based on length, weight, and age data, we examined allometry and growth parameters for common pandora, Pagellus erythrinus, commercially collected seasonally from northern and southern Tunisian coasts in 2007. A total of 370 specimens (14–27.5 cm in length) were used to assess the allometric variation at seasonal scales. The slope b values (regression coefficient) of the length-weight relationship varied between 2.494 to 3.237, indicating (roughly) an isometric to negative allometric growth pattern. The allometric relationship, as a proxy for fish condition, seems to be affected by seasons and sex in the northern population, while only seasons seem to have a strong effect in the southern population, as indicated by ANOVA. The von Bertalanffy growth parameters were identified at L∞ = 34.076 and 28.017 cm, k = 0.153 and 0.150/year, and t0 = −1.922 and −3.961 years for the northern and southern sample, respectively.