Exploring Saduria entomon (Crustacea Isopoda) as a New Source for Chitin and Chitosan Isolation.

Chitin and chitosan demand is growing very fast due to interest from industries such as pharmaceutical, cosmetic, agricultural and others. New sources for chitin and chitosan isolation are being extensively searched to fulfil this demand. In this paper, Saduria entomon a Baltic benthic crustacean, is evaluated as a source for chitin and chitosan isolation. Chitin and chitosan yield from S. entomon were 14.8 and 8.2%, respectively, in a similar range to other sources. Samples were characterized in terms of physicochemical properties (acetylation degree, molecular weight, thermal stability, and crystallinity) and two biological properties, antimicrobial activity and antioxidant activity were evaluated. Chitosan S. entomon exhibited antimicrobial activity against S. aureus but not against E. coli. An antioxidant activity of 20.98 TROLOX µmol equivalent/g polymer was detected for the chitosan sample. These properties are very promising for the use of this organism as a source for chitin and chitosan isolation in the biomedical field.

Expansion of alien gammarids in the Vistula Lagoon and the Vistula Delta (Poland).

Amphipod crustaceans belong to the most successful invaders of aquatic environments. The work provides information concerning the spatial and temporal scales of expansion of four alien gammarid amphipods (three of them of Ponto-Caspian and one of North American origin): Pontogammarus robustoides (G.O. Sars, 1894), Obesogammarus crassus (G.O. Sars, 1894), Dikerogammarus haemobaphes (Eichwald, 1841), and Gammarus tigrinus Sexton, 1939 in the Vistula Lagoon (VL) and the Vistula Delta (VD) in 2008-2010. The mean abundance of these gammarids in nearshore zones was 382 ind m(-2) in VL and 89 ind m(-2) in VD. Their mean biomasses were likewise greater in VL (0.91 g m(-2)) than in VD (0.49 g m(-2)). G. tigrinus was the most dominant species in both nearshore zones of VL and VD and attained the highest frequency in these areas. The study gives evidence of total extinction of native gammarid species.