S. Focardi

Antimicrobial activity against Helicobacter pylori strains and antioxidant properties of blackberry leaves (Rubus ulmifolius) and isolated compounds

Rubus spp. (Rosaceae) provide extracts used in traditional medicine as antimicrobial, anticonvulsant, muscle relaxant and radical scavenging agents. Resistance to antibiotics used to treat Helicobacter pylori infection as well as their poor availability in developing countries prompted us to test the antimicrobial activity of Rubus ulmifolius leaves and isolated polyphenols against two H. pylori strains with different virulence (CagA+ strain 10K and CagA(-) strain G21). The antioxidant activity (TEAC values) of the tested compounds ranged from 4.88 (gallic acid) to 1.60 (kaempferol), whilst the leaf extract gave a value of 0.12. All the isolated polyphenols as well as the leaf extract showed antibacterial activity against both of the H. pylori strains. The minimum bactericidal concentrations (MBCs) of the extract for H. pylori strains G21 and 10K, respectively, were 1200 microg/mL and 1500 microg/mL after 24h of exposure and 134 microg/mL and 270 microg/mL after 48 h exposure. Ellagic acid showed very low MBC values towards both of the H. pylori strains after 48 h (2 microg/mL and 10 microg/mL for strains G21 and 10K, respectively) and kaempferol toward G21 strain (MBC=6 microg/mL). A relationship between antimicrobial activity and antioxidant capacity was found only for H. pylori strain G21 CagA(-) strain.

Environmental heterogeneity patterns and assessment of trophic levels in two Mediterranean lagoons: Orbetello and Varano, Italy

The management of coastal lagoons is of particular interest due to their high economical importance. In spite of their great productivity, coastal lagoons are often impacted by human pressure which produces water eutrophication. The aim of this paper is to assess the trophic state of the two Mediterranean lagoons taking into account chemical-physical parameters, nutrient concentrations and biological parameters. Two Italian lagoons, Orbetello and Varano (respectively located in Tyrrhenian and Adriatic coast, Italy) were studied between May 2003 and April 2005. Both these systems receive treated urban outflows, agricultural effluents and rivers freshwater inputs. Field collected data showed that studied lagoons were characterized by different human and natural pressures. Orbetello showed the highest water eutrophication, highlighted by the trophic index values, while Varano showed lower eutrophication levels except for the summertime. The values of physical, chemical and biological parameters measured in Orbetello and Varano lagoons indicate that a wide spatial and seasonal gradient of the water characteristics was established during the study period, but in particular in winter. This gradient, typical of estuarine systems, was essentially due to the mixing of freshwater, seawater and anthropogenic inputs. Orbetello lagoon seemed much more affected by the urban impact and the fish-farming activities than Varano lagoon, but the latter showed a greater agriculture activities impact as showed by the remote sensing images.

Heavy metals in organisms from the Northern Tyrrhenian sea

The concentrations of zinc, manganese, copper, cadmium, lead and mercury have been determined in soft tissues of four marine organisms (Mytilus galloprovincialis Lmk., Nephrops norvegicus L., Mullus barbatus L., Engraulis encrasicolus L.) collected seasonally from the winter of 1976 to the spring of 1980 in various areas of the Tyrrhenian Sea (western Mediterranean). In all four species levels of all metals, except mercury in all areas are alike while mercury levels vary and, furthermore, are higher than in specimens from other areas of the Mediterranean and also from other seas. The possible natural origin of the mercury from cinnabar (HgS) ore as well as the suitability of the four species as bioindicators is discussed.

Relationship between organochlorine contaminants and mixed function oxidase activity in skin biopsy specimens of Mediterranean fin whales (Balaenoptera physalus)

The relationship between organochlorine contaminants (PCBs and DDTs) and mixed function oxidase, benzo(a)pyrene monooxigenase activity (BPMO), was investigated in skin biopsy specimens from fin whales (Balaenoptera physalus) of the Mediterranean Sea. Skin biopsy material, sampled by a non invasive technique, is suitable for a wide range of chemical and biomarker analysis. In this study PCBs and DDTs were evaluated in subcutaneous blubber and MFO activity in epidermis. An interesting correlation was found in male specimens between the two variables.

Persistent organochlorine residues in fish and water birds from the Biobio River, Chile

Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites, HCH isomers and hexachlorobenzene (HCB) were determined in fish and birds from different locations in the Biobio river basin (central Chile). Samples collected near the mouth of the river contained high concentrations of PCBs, reflecting the massive use of these xenobiotics in the urban and industrial areas of Concepcion and Talcauano. Samples collected in the central part of the basin contained very high concentrations of lindane that coincide with the widespread use of lindane-based pesticides (purified γ-HCH) in this area. DDT was distributed homogeneously throughout the basin, except at Laguna Icalma, the source of the river in the Andes. Most PCB residues in fish and birds consisted of congeners between penta- and hepta-chlorobiphenyls. In fish, the predominant congeners were the pentachlorobiphenyl 23′44′5 (IUPAC number 118) and the hexachlorobiphenyl 22′344′55′ (PCB-153); in birds 22′44′55′ (PCB-180) prevailed.

Chlorinated hydrocarbons in the tissues of South Polar Skuas (Catharacta maccormicki) and Adélie Penguins (Pygoscelis adeliea) from Ross Sea, Antarctica

High rates of egg infertility and embryo death in a colony of South Polar Skuas breeding in the Antarctic were similar to those in polluted North Atlantic populations of the Great Skua. Such loss could not be linked to factors such as organochlorine pollutants, as levels of DDE and PCBs in the contents of skua eggs from the population were only a small fraction of those in polluted skua populations from the Northern Hemisphere. Average eggshell thickness for skuas nesting on Ross Island has shown no significant change since the introduction of DDT. Concentrations of DDE and PCBs in South Polar Skuas were 13 and 22 times higher, respectively, than those in the eggs of sympatric Adélie Penguins, and this probably reflects the greater exposure of skuas to pollution when they migrate north of the Antarctic Convergence in winter. Residues in liver tissue showed a similar trend, and a higher rate of mixed function oxidase induction in skua liver compared to that of penguins is consistent with the trends seen in pollutant levels. The same PCB congener predominated in both skua and penguin samples. Comparisons with historical residue data suggest that global levels of DDT residues are declining.

Heavy Metals and Chlorinated Hydrocarbon Concentrations in the Red Fox in Relation to Some Biological Paramaters

Heavy metals and organochlorine contamination were analyzed in tissues of red foxes (Vulpes vulpes) from the Province of Siena (central Italy). Mercury (Hg), cadmium (Cd) and lead (Pb) concentrations were assessed in liver tissues and the data were analyzed for differences in relation to sex and age. Overall Hg, Cd and Pb mean values were 0.16, 0.62 and 0.64 μg g_1 d.w., respectively. HCB, DDT and PCB concentrations were assayed in fatty tissues and muscle. The highest levels of those pollutants were found in muscle (0.47, 1.16 and 20.2 μg g_1 lipid basis of HCB, DDTs and PCBs respectively), rather than in fat (0.23, 0.49 and 7.2 μg g_1 l.b. of HCB, DDTs and PCBs respectively). Pollutant accumulation was analyzed in relation to sex, age and sexual maturity of females.

Trace elements and chlorinated hydrocarbons in eggs of Pelecanus crispus, a world endangered bird species nesting at Lake Mikri Prespa, North-western Greece

Eggs of the Dalmatian pelican, Pelecanus crispus, collected from 1984 to 1986 at Lake Mikri Prespa, north-western Greece, contained residues of trace elements and PCBs at low concentrations, and of DDE at rather high concentrations. DDE is negatively related to eggshell thickness. Eggshell thickness was reduced by 12-20% in comparison with the pre-1947 (before DDT use) eggshell thickness. However, this decrease did not affect the reproductive success of this species. The main fish species eaten by the Dalmatian pelican at Lake Mikri Prespa were analyzed for pollutants. All the fish contained low concentrations of residues. The contribution of the diet while the birds are on the wintering grounds is unknown. Recommendations for a monitoring programme of pollutants in eggs of the Dalmatian pelican, a world-endangered species, are proposed.

Distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of some Italian lagoons exploited for aquaculture and fishing activities.

The concentrations of 16 PAHs in surface sediments collected from four Italian lagoons, exploited for aquaculture and fishing activities, during the period 2004–2007, were analysed. Some molecular ratios and Pearson correlations were used in order to estimate the origin of the pollution and similar transport of PAH sources. Principal Component Analysis (PCA) and Cluster Analysis were used in order to highlight dissimilarities among sampling sites. Concentrations of total 16 PAHs varied significantly among the lagoons as well as within the same basin. Sediments of Orbetello lagoon showed the highest level of contamination (mean of 98.78 ng g−1), followed by that in Santa Giusta (48.15 ng g−1), Lesina (31.06 ng g−1) and Varano (25.19 ng g−1). These results were linked to the greater industrialisation and urbanisation of the catchment area of both Orbetello and Santa Giusta compared with Lesina and Varano. A considerable predominance of 4-rings PAHs was observed for Lesina (52%,), Varano (77%), Orbetello (50%) and Santa Giusta (57%) and Pyrene was the dominant compound. On the other hand, phenanthrene is the dominant compound of low molecular weight contaminants for all the studied lagoons. A meaningful pyrolytic contribution to pollution was found in the sediments of Lesina lagoon, dominated by benzo[a]pyrene (7.27 ng g−1) and benz[a]anthracene (4.14 ng g−1), due to intensive traffic. For Varano, an evident petrogenic contamination was observed along the western area, due probably to accidental oil spillage. All 16 PAHs were found to be correlated in Orbetello and Santa Giusta lagoons and the compounds present in Santa Giusta sediments, near the urban centre, were shown to be mainly of pyrolytic origin. A much more complex situation was observed in Orbetello, where a mixed pattern of pyrolytic and petrogenic inputs was observed.

Assessment of environmental pollutants in ten southern Italy harbor sediments.

In 2003–2006, the distribution of macronutrients and pollutants of environmental interest was investigated in surficial sediments collected from 10 southern Italy harbors selected in four different regions. About 167 stations were sampled to determine levels of total organic carbon, total nitrogen, total phosphorous, trace elements (Al, Cd, Pb, Ni, Cr, Cu, Zn, Hg, As), short- and long-chain aliphatic hydrocarbons (Hy C > 12 and Hy C < 12), and concentrations of persistent organic pollutants (polychlorinated biphenyls, polycyclic aromatic hydrocarbons [PAHs], p-p-Dichlorodiphenyldichloroethylene (4,4′-DDE), and Hexachlorobenzene (HCB). General relationships between studied variables and harbors systems were explored by multivariate statistical approaches. Results show that wide fluctuations are reported for all variables both among harbors and inside each studied system. Principal components analysis suggests that major significance in explaining total average variability is due to lead, copper, zinc, silts, sands, and PAHs. No significance has been observed when testing nonmetric multidimensional scaling distributions relating with the factor “region,” while performing analyses on factor “main human activity,” a higher significance is observed. These results suggest a strong relationship between the main human use of marine systems and observed pollution levels in sediments.