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Giuseppe Corriero
Ruolo
Professore Ordinario
Organizzazione
Università degli Studi di Bari Aldo Moro
Dipartimento
DIPARTIMENTO DI BIOLOGIA
Area Scientifica
AREA 05 - Scienze biologiche
Settore Scientifico Disciplinare
BIO/05 - Zoologia
Settore ERC 1° livello
Non Disponibile
Settore ERC 2° livello
Non Disponibile
Settore ERC 3° livello
Non Disponibile
Population abundance, distribution and habitat preference of the Mediterranean sympatric seahorses Hippocampus guttulatus and Hippocampus hippocampus were investigated in a semi-enclosed sea system (Apulian coast, Ionian Sea). A total of 242 individuals of seahorses were sighted in the 11 transects surveyed in summer 2011. Hippocampus guttulatus (n = 225) were 14 times more abundant than H. hippocampus (17). The mean abundance of H. guttulatus for all the pooled sites was 0.018 m-2 (SE ± 0.003) ranging from a maximum of 0.035 (SE ± 0.007) to a minimum of 0.008 (SE ± 0.002). The size structure of long-snouted seahorse shows a population ranging from 7 to 14 cm (SL) with a peak at 10 cm (TL). Juveniles (96.0 ± 8.0 mm) represent a significant fraction of the population, accounting more than 21% of the sighted individuals. In Mar Piccolo, H. guttulatus is able to shelter both in monotonous habitats, including the algal beds, and diversified ones, such as the rich filter-feeder communities that colonize hard substrates. By contrast, H. hippocampus is mainly associated with habitats of low complexity. Today, the Mar Piccolo di Taranto is among the most heavily polluted water bodies in South Italy, with trace metals, hydrocarbons, pesticides and organic wastes affecting both biotic and abiotic matrices. However, despite the high level of degradation, the presence of a large mussel farm has avoided the impact of towed fishing gears, and eutrophication of water bodies has ensured a high trophic level that supports large crustacean populations, potential prey for seahorses.
Lindane is an organochlorine pesticide that has been widely used to treat agricultural pests. It is of particular concern because of its toxicity, persistence and tendency to bioaccumulate in terrestrial and aquatic ecosystems. In this context, we investigated the ability of the demosponge Hymeniacidon perlevis to bioremediate lindane polluted seawater during in vitro experimentation. Lindane was extracted by solid-phase micro-extraction (SPME) and determined by gas chromatography–mass spectrometry (GC–MS). Furthermore, we assessed the role exerted in lindane degradation by bacteria isolated from the sponge. Sponges showed low mortality in experimental conditions (lindane concentration 1 μg/L) and were able to remove about 50% of the lindane content from seawater in 48 h. Bacteria isolated from sponges showed a remarkable remediating capacity (up to 97% of lindane removed after 8-days). A lindane metabolite was identified, 1,3,4,5,6-pentachloro-cyclohexene. The results obtained are a prelude to the development of future strategies for the in situ bioremediation of this pollutant
Sponges can filter large amounts of water, which exerts an important grazing impact on free bacteria, an important component of the diet of sponges. We examined the accumulation of bacteria in the Demospongiae (Hymeniacidon perlevis). Analyses were performed on homogenates from unstarved and starved sponges in seawater from their sampling site (the Ionian Sea). Culturable heterotrophic bacteria (22 °C), total culturable bacteria (37 °C) and vibrios densities were measured on marine agar 2216, plate count agar and TCBS agar, respectively. Total and fecal coliforms, as well as fecal streptococci, were determined by the most probable number method (MPN). H. perlevis was able to accumulate all of the six microbiological groups. Bacterial groups differed in their resistance to digestion by H. perlevis. Our data suggest that H. perlevis may accumulate, remediate and metabolize bacteria and that they may be employed as a useful bioindicator and bioremediator.
The biodiversity of the Santa Maria di Leuca (SML) coral bank is summarized and its description is updated using data collected by means of underwater video systems, benthic samplers and fishing gears. A total of 222 living species have been recorded within the coral bank area in the depth range 280-1121 m. The most abundant benthic taxa recorded are Porifera (36 species) followed by Mollusca (35) and Cnidaria (31). The scleractinian corals Madrepora oculata and Lophelia pertusa are the main colonial species in the structure of the SML bank. Annelida, Crustacea and Bryozoa have been found with 24, 23 and 19 species, respectively. A total of 40 species of demersal fish have been recorded. Other faunal taxa were found with small numbers of species. One hundred and thirty-five species are new for the SML bank, 31 of which represent new records for the north-western Ionian Sea (2 Porifera, 17 Cnidaria, 1 Mollusca, 3 Annelida, 2 Crustacea, 4 Bryozoa and 4 Echinodermata). The finding of the annelid Harrnothoe vesiculosa represents the first record for the Mediterranean Sea. The SML coral bank represents a biodiversity "hot-spot" on the bathyal bottoms of the Mediterranean Sea. (C) 2009 Elsevier Ltd. All rights reserved.
Numerous studies have focused on the soft bottom macrozoobenthos from Mediterranean transitional environments, pointing out a correlation between the variation in environmental parameters and changes occurring in benthic communities. Less attention has been paid to the study of hard bottom organisms settling on both natural and artificial substrates usually present within the basins and often constituting peculiar communities. The ecological role of such communities is remarkable, since they often reach high values of species richness and include bioconstructor organisms able to build true reefs. These reefs can strongly impact the environment, improving biodiversity through the increase of spatial heterogeneity. The present work aims to supplement new faunistic data on five lagoon systems of the south-eastern Italian coast, integrating the still fragmentary knowledge of their macrozoobenthos through the study of hard substrate communities. Sampling was performed on hard substrates colonized by complex benthic communities. The assemblages recorded were then compared in the light of the study sites’ main ecological traits. Our data highlighted the occurrence of a rich benthic macrofauna, with 100 taxa found. This markedly increases the value of species richness reported in the literature for the macrozoobenthos of the study sites. In particular, the species list provided for the Ugento Basins was the first ever compiled for this site. In spite of their geographical proximity, the investigated sites, according to their diverse environmental conditions, showed substantial differences as regards their respective macrozoobenthic communities.
The demosponge Tethya citrina Sarà & Melone was subjected to long-term aquarium farming, considering that several spe- cies belonging to this genus are a rich source of useful bioactive compounds, and in particular interesting bioactive proteins. The rearing method in the present research was mainly based on applying parameters taken from the current literature. The biological activity of the sponge was assessed in terms of survival and growth over time, status of ltering apparatus, and protein banding pro les. Farmed sponges showed a high survival rate and marked reduction in size. In addition, they were frequently affected by massive production of asexual buds. Histological and ultrastructural observations showed a gradual disorganization of the sponge choanocyte chambers, with a drastic reduction in choanocytes and a progressive increase in spherulous cells. Comparative electro- phoretic analysis of the protein pro les of wild and reared specimens showed differences in protein composition and abundance between the tested groups. Such data are consistent with the increase in spherulous cells whose content was markedly electron- dense, a feature stressing the proteinaceous nature of these inclusions. Experimental tank-rearing of Tethya provided promising responses in terms of high survival rate of the species and easy reproduction, though the rearing protocol used led to profound morpho-functional changes in the sponge. This con rms the inadequate state of knowledge on farming techniques for this taxon, while also highlighting potential applications in biotechnology of ex situ breeding techniques, in order to modify the sponges’ biological responses.
Marine natural products extracted from sponges represent a new source for drug discovery. Here we describe a simple method for preparing aqueous extracts from 7 Mediterranean demosponges, which allowed the extraction of water-soluble compounds, such as proteins by homogenization of sponge tissue in phosphate buffered saline (PBS).The comparative analysis by SDS-PAGE showed differences in number of bands, bandwidth and intensity among the sponges analyzed. The PAS/silver staining revealed a substantial and different glycoprotein assortment among the demosponges studied.To further study the biological activities present in the sponge extracts, we determined the non-cytotoxic doses on four different mammalian cell types demonstrating that the optimal non-cytotoxic doses were cell type- and extract-dependent.In conclusion, the extraction method described in this paper represents a fast and efficient procedure for the extraction of water-soluble proteins from marine sponges. Furthermore, the cell viability data suggest the feasibility of this method for the direct in vitro cell-based assays.
Preliminary data about the presence and distribution of Corallium rubrum along the Ionian Apulian coast are here reported. The study has been carried out in the areas of Santa Caterina and Santa Maria di Leuca (LE) at about 60-80 m of depth, by SCUBA diving. At Santa Caterina the colonies of Corallium rubrum showed values of density and size comparable to those of the most preserved Mediterranean populations, whereas lower values were recorded at Santa Maria di Leuca, thus suggesting the hypothesis of a major impact due to fishing activity in this site.
In recent years, several episodes of mass mortality of sessile epibenthic invertebrates, including sponges, have been recorded worldwide. In the present study, we report a disease event on Ircinia variabilis recorded in September 2009 along the southern Adriatic and Ionian seas (Apulian coast), with the aim to quantify the mortality incidence on the sponge population, to investigate the effect of the disease on the sponge tissues and to assess whether the disease is associated with vibrios proliferation. The injured sponges showed wide necrotic areas on the surface or disruption of the body in several portions. Necrotic areas were whitish and often were covered with a thin mucous coat formed by bacteria. In the most affected specimens, sponge organisation resulted partial or complete loss, with the final exposure of the dense skeletal network of spongine fibres to the environment. The results of microbiological cultural analysis using in parallel Marine Agar 2216 and thiosulphate/citrate/bile salts/sucrose agar demonstrated that, in affected specimens, vibrios represented 15.8 % of the total I. variabilis surface culturable bacteria. Moreover, all the isolated vibrios, grown from the wide whitish areas that characterize the surface of the diseased sponges, were identified, and their assignment to the Vibrio rotiferianus was consistent with phylogenetic analysis and data of morphological, cultural and biochemical tests. Studies on V. rotiferianus have shown that its pathogenicity, with respect to various aquatic organisms, is higher than that of Vibrio harveyi. The factors triggering the disease outbreak in Ircinia variabilis populations remain unclear. At present, we can hypothesize the involvement in the disease of a synergetic mechanism that, under stressful physiological conditions (high temperature, elevated nutrients and reduced water flow), induces sponge pathogens, in our case V. rotiferanius, to become virulent, making sponges unable to control their proliferation. Additional studies are needed to understand the etiological processes as well as the factors involved in sponges recovering from this epidemic event allowing them to face mass mortality. A drastic reduction of sponge-specific representatives could have marked a negative impact on the environmental health on account of their role in the sea remediation processes as filter-feeding organisms.
The calcareous sponge Paraleucilla magna, originally observed along the Brazilian coast (Atlantic Ocean), is the only allochthonous invasive species of Porifera reported in the Mediterranean Sea. A 1-year investigation of the population dynamics and life-cycle of this exotic species in the Mar Piccolo di Taranto (southern Italy, central Mediterranean Sea) has provided a good opportunity to test how environmental variations can influence its life-cycle and to ascertain what strategy can be adopted to successfully colonize a new environment. In the Mar Piccolo di Taranto, P. magna exhibits marked temporal changes in biomass. The specimens studied reproduce almost all year round, showing a seasonal pattern that peaks during warm months. This prolonged sexual activity allows P. magna to continuously produce young specimens, with repeated recruitment events taking place throughout the year, thus offsetting the seasonal mortality of adult specimens. This r-strategy enables the non-indigenous sponge to achieve a high degree of maintenance over relatively long periods (ten years at least).
Clionaids are excavating sponges, which live in and grow into calcareous substrates. We studied the sexual reproductive cycles of two clionaid sponges coexisting in a Mediterranean coastal basin (Porto Cesareo, Italy), Cliona viridis and Cliona celata, by analyzing monthly tissue samples of ten specimens of each species collected over a 2-year period. From May to June of the second study year, supplementary samples were taken weekly. Up to 90% of the specimens of C. viridis and 70% of those of C. celata sampled were reproductive during the study. In both species, but particularly in C. viridis, reproductive investment, measured as the percentage of sponge tissue occupied by gametes, was high. Oocytes were present almost year-round in both species, except for a 1-4-month period after zygote release. In contrast, spermatogenesis occurred most frequently in May in both species, when (May-June) oocytes reached their greatest diameters. Cliona viridis and C. celata are hermaphrodites, with oocytes and spermatic cysts coexisting in 10% of the studied individuals in the first year of the study, and in 30% during the second. No developing embryos or larvae were incubated in the sponge tissues, and fertilization was not observed. Temperature may play a role in triggering some important phases of the reproduction of these Cliona, such as oocyte maturation and spermatogenesis, which occurred when water temperature increased from 17 degrees C to 25 degrees C between May and June.
The relevance of the budding process in a population of Tethya citrina inhabiting an unpredictable environment subjected to frequent anoxic crisis (Mar Piccolo di Taranto) is described, and new data about the fate of the buds after their release are provided. At the individual level, for the first time in natural conditions, it has been demonstrated that several budding events follow each other, alternating with short periods (1-2 months) of rest. At the population level, budding proved to be a continuous process, being detected throughout the 13 months of study, with a short summer decrease both in the frequency of budding specimens and bud density. This trend was markedly different from that reported for conspecific populations inhabiting stable environments, in which budding is a seasonal process. It is hypothesized that the sudden and unpredictable variations of the ecological conditions could be responsible for the onset of repeated budding events, thus stressing the role of environmental factors in affecting the asexual reproductive pattern. T. citrina buds, here investigated, tend to detach from the adult sponge within 7/15 days of their differentiation, a feature coherent with experimental data carried out under laboratory conditions. A significant relationship between the size/age of the post-buds and the onset of the asexual reproduction has been proved: in particular, the first budding event was observed in nine-month-old sponges, measuring about 7 mm in diameter. As reported for other demosponges, in T. citrina post-buds the growth rate was positively related to the water temperature, with a significant increase during the summer. In addition, a negative effect of the budding process on the sponge growth, is hypothesized for a post-bud subjected to repeated budding events. Growth rate, however, proved highly variable. (C) 2010 Elsevier B.V. All rights reserved.
The macrozoobenthic assemblage from the Karavasta lagoon system, the main wetland of Albania, was studied on soft bottoms and artificial hard substrates. Three different communities were identified: the typical 'brackish-water community', an 'outlet community' dominated by filter-feeders, and a typical 'marine community', inhabiting fine sandy bottoms, where polychaetes are dominant, together with a few species of tunicates and bivalves, which colonize hard substrates. The occurrence of build-ups of the bryozoan Conopeum seurati, settled on the upper portion of long submerged wooden poles, was the main feature of faunistic interest. The faunistic affinity between the zoobenthic assemblage recorded in the hyperhaline lagoon of Karavasta and the assemblages from two Italian lagoons, the brackish Lake of Lesina and the euhaline Lake of Fogliano, was considered according to the different hydrological conditions and the geographical location. Hydrological confinement and salinity were likely to be the leading factors influencing the benthic community composition in the Karavasta wetland area. Therefore, on a vaster spatial scale, the isolation and geographical proximity of the ecosystems and colonizing ability and dispersal changes of the species appear to be the main factors liable to produce faunal variations.
The present study focuses on the reproductive success of transplants of the bath sponge Spongia officinalis Linnaeus, 1759, with the aim of investigating the possibility of restocking this species, one of the most endangered organisms of the Mediterranean sessile zoobenthos. Transplants of S. officinalis, collected from a wild population along the Apulian coasts (Ionian Sea, Italy), have been moved into an area where the species was present in the past. The transplants consisted both of specimens in toto and of fragments of different sizes, obtained after having cut the mother sponge into pieces. All transplanted sponges showed complete cicatrisation of the cut surfaces within a month of the initial manipulation and had a survival rate of 100% throughout the 12 months of the study. From the present investigation, it has emerged that the reproductive effort and the larval release by the transplants do not differ significantly from those shown by the source population. This successful technical approach supports its application as a strategy for restocking the population of this endangered species.
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