Biological, Biochemical and Elemental Traits of Clavelina oblonga, an Invasive Tunicate in the Adriatic Sea

Clavelina oblonga is an invasive tropical tunicate recently introduced into the Adriatic Sea as a consequence of globalization and climate change. Mussel aquaculture sites provide an ideal environment for this colonial ascidian, where it has recently become the dominant fouling species. This study represents the first investigation of its biological and physical characteristics, as well as its proximal, fatty acid, macroelement, trace element, and toxic metal composition. The entire-tissue chemical composition of C. oblonga resulted in 95.44% moisture. Its composite structure revealed several strong peaks, attributed to O-H, C-H, C-N, and C=O stretching, along with cellulose components overlapping with proteins and carbohydrates. The major fatty acids were palmitic, stearic, and docosahexaenoic acid, followed by docosanoic, elaidic, linoleic, and myristic acid. The saturated fatty acids, polyunsaturated fatty acids, and monounsaturated fatty acids comprised 51.37, 26.96, and 15.41% of the total fatty acids, respectively. Among the analysed trace and macroelements, aluminium and sodium were predominant. C. oblonga exhibited different concentrations of toxic metals, such as arsenic and lead, compared to fouled mussels in the Istria region. It appears that the tunicate has adapted to the environmental conditions of the Adriatic, reaching its maximum spread and biomass in mid-autumn. There is a strong possibility that C. oblonga could colonize and establish itself permanently in the Adriatic. This would have a strong negative impact on shellfish farming, the structure of the ecosystem, plankton biomass, and the distribution of other marine species. However, it also represents a biomass resource with high potential of utilization in different industries

Procjena unosa bakra umjerenom konzumacijom vina

To estimate Cu exposure level from wine consumption and to assess possible health risk for moderate wine consumers, wine samples were collected from different wine-growing areas of Croatia. Median concentrations were 180 μg L-1, range (76 to 292) μg L-1, in commercial wines and 258 μg L-1, range (115 to 7600) μg L-1, in homemade wines (P>0.05). Maximum permitted level of 1000 μg L-1 was exceeded in three homemade wines. However, daily intake of Cu from wine (in the range from 0.02 mg d-1 to 1.52 mg d-1) estimated from Cu concentration in all wine samples is lower than the tolerable upper intake level of 5 mg d-1 proposed by the EU Scientifi c Committee on Food and does not present a risk to moderate wine consumers.Kako bi se procijenila razina izloženosti bakru prilikom konzumacije vina te utvrdili mogući zdravstveni rizici za umjerene potrošače vina, skupljeni su i ispitani uzorci vina iz različitih vinogradarskih područja Hrvatske. Koncentracije Cu bile su u rasponu od 76 μg L-1 do 292 μg L-1 (medijan 180 μg L-1) u komercijalnim vinima te od 115 μg L-1 do 7.600 μg L-1 (medijan 258 μg L-1) u vinima domaće proizvodnje (P>0,05). U tri ispitana vina domaće proizvodnje koncentracija Cu bila je iznad najviše dopuštene od 1000 μg L-1. Međutim, izračunani dnevni unos Cu u slučaju konzumacije ispitanih vina (u rasponu od 0,02 mg d-1 do 1,52 mg d-1) ne prelazi gornju granicu tolerancije unosa od 5 mg d-1 te nije zdravstveni rizik umjerenim potrošačima vina