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Abstract: The variability of the proximate composition and fatty acid profiles in samples of sprat (Sprattus sprattus balticus) from the southern Baltic Sea were studied in relation to the catch season and location, individual fish size, and sex. Fatty acid profiles depended on such features as fish size and lipid content, which depend on the season of the year in which the fish were caught. No differences in fatty acid profiles were noted between the sexes in the individuals examined. Studies on fish lipids are necessary as fish lipids are important in the prevention of cardiac disease. One of the chief advantages of fish lipids that is relevant to the prevention of cardiac disease is their n−3 to n−6 fatty acid ratio. The most advantageous ratio of these fatty acids was noted in sprat that were the smallest in length. [Copyright &y& Elsevier]

The fat content and fatty-acid profiles of herring, Clupea harengus membras, from the southern Baltic Sea varied depending on when (fishing season) and where (fishing grounds) the fish were caught as well as on their size and sex. The fat, protein and dry matter content and the fatty-acid profiles were assayed in C. h. membras muscle tissue. The changes observed in fatty-acid profiles were determined by factors such as specimen mass and fat content, which, in turn, depended on fishing season. This is explained by dietary differences between juvenile and older fish. Gonad maturation and spawning in the latter are also factors. The study results provide confirmation of the hypothesis that polyunsaturated fatty acids (PUFA), in particular docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), play vital roles in the sexual maturation of C. h. membras. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports concentrations of seven polybrominated diphenyl ether (PBDE) congeners in selected fish species that were collected from the southern Baltic in the 2004–2006 period. Differences in concentrations of PBDEs among the fish species were observed. The mean ∑7PBDE concentrations measured in herring (Clupea harengus), sprat (Sprattus sprattus), and salmon (Salmo salar) samples were 1.2ngg−1 wet weight, 1.6ngg−1 wet weight, and 2.5ngg−1 wet weight, respectively. PBDE-47 was the prevalent congener in all the samples tested. PBDE concentrations in the herring samples tested in the current study were similar to those determined in herring sampled in the northern Baltic, but slightly lower in comparison with concentrations in fish from the Belgian North Sea. PBDE levels occurring in salmon sampled in the southern Baltic were lower than those measured in the northern and northeastern Baltic, but similar to levels determined in salmon from the central part of the Baltic Sea. The risk posed by consuming the fish tested in the current study was evaluated according to the Provisional Tolerable Weekly Intake (PTWI) value for PBDEs recommended by the European Food Safety Authority (EFSA). [Copyright &y& Elsevier]

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in the southern Baltic herring (Clupea harengus), sprat (Sprattus sprattus), and salmon (Salmo salar) are reported. The significant interspecies and season-specific differences in PCDD/Fs and dl-PCBs concentrations were observed. The contribution of dl-PCBs to the total toxicity equivalents (TEQs) ranged between 50% and 70%, dependently on fish species. In all samples, concentrations of PCDF were higher in comparison with that of PCDD. The permissible limits of the content of PCDD/Fs and dl-PCBs (8pgg−1 fresh weight for the sum of PCDD/Fs and dl-PCBs, and 4pgg−1 fresh weight for the PCDD/Fs) were exceeded mainly in salmon samples (in 80% of salmon samples studied). The elevated levels of PCDD/F and dl-PCB were observed only in two of seventy two herring samples, and in ten of 62 sprat samples. The multiple regression analysis revealed that fish lipid content, and concentration of PCB 153, used simultaneously, might be useful in the prediction of TEQ values of fish samples. These two variables explained more than 80% of total variance. For all fish species studied, the correlation coefficients obtained with the multiple regression analysis were higher than that obtained with the regression analysis involving total TEQ values, and only one independent variable: fish lipid content. [Copyright &y& Elsevier]

Levels of seven marker polychlorinated biphenyls (PCBs) have been determined in five species of Baltic fish collected during 1997–2006. Downward time trends in the concentrations of heavier congeners of PCBs in different Baltic fish, with the exception of cod, have been observed between 1997 and 2001. In case of sprat and herring samples, the statistical significance of the time trends of the PCBs: 101, 118, 153, 138 and 180 concentrations has been proved. Species-specific bioaccumulation of PCBs has been indicated, and the lowest and highest levels of PCBs (expressed on the basis of lipid weight) have been observed in sprat and salmon samples, respectively. PCB profiles have been found to be similar in all the fish species tested. Sampling location has not been a crucial factor for the observed levels of various PCBs. In some fish species, PCB concentrations are negatively correlated with the fat content but have no relation with the fish length. [Copyright &y& Elsevier]

The levels of HCH isomers, HCB and were determined in five species of Baltic fish collected during 1995–2006. Some downward time trends of HCH isomer, pp′-DDE and pp′-DDD concentrations in Baltic fish were observed; in contrast, HCB and DDT concentrations did not exhibit any obvious trend. Concentrations of expressed on a lipid weight basis were very similar in all species studied. In contrast, concentrations of varied in tested species. The most abundant HCH isomer was β-HCH and among DDT-related compounds, pp′-DDE prevailed. In our investigations the sampling sites were not a crucial factor for organochlorine pesticide concentrations and patterns observed in fish, but the occurrence of several inter-species differences in the bioaccumulation features of OC pesticides were observed. For cod there was a positive correlation between fish size (length) and concentration. In herring, sprat and salmon samples, concentrations were negatively correlated with fat content. [Copyright &y& Elsevier]

Abstract: We present the first attempt at quantitative analysis of morphological diversity of tailed viruses obtained from marine sediments without ultracentrifugation or enrichment on specific host strains. Sandy mud samples were collected in the Gulf of Gdańsk in the spring, autumn and winter. VLPs were analyzed by transmission electron microscopy. The distribution of three groups of tailed phages was similar in all seasons (Siphoviridae: 52% on average; Myoviridae: 42%; Podoviridae: 6%). 19% of siphoviruses had prolate heads. Interestingly, 11% of siphoviral particles had tails longer than 300 nm, and 6% longer than 600 nm. [Copyright &y& Elsevier]

Cyanobacteria are a rich source of biologically active compounds used in pharmacology and biotechnology. Due to their high capacity of adaptation, which is reflected in the production of diverse metabolites, including toxins, these microorganisms are able to inhabit very different environments. In this work, water and ethanol extracts from 11 cyanobacterial strains derived from the Baltic Sea ( Microcystis, Synechocystis, Leptolyngbya, Pseudanabaena, Lyngbya, Phormidium, Nodularia and Anabaena genera) were screened for anticancer activity. MCF-7 human breast cancer and HeLa cervical cancer cell lines, as well as HDFa normal human fibroblasts, were used. Three extracts derived from Pseudanabaena sp., Pseudanabaena cf. galeata and Microcystis aeruginosa revealed potent and selective antiproliferative activities against cancer cells. The mechanism of the anticancer activity was explored in MCF-7 cells, and was found to rely on the inhibition of the pro-survival Akt kinase and induction of cell death. The peptide profiles of selected cyanobacterial extracts were determined using LC-MS/MS, and classes of bioactive compounds that might be potentially responsible for the observed anticancer activities are presented. [ABSTRACT FROM AUTHOR]