Chitin characterization of two Baltic Sea shrimp species : Palaemon elegans and Crangon crangon

Abstract

Chitin is a biopolymer, which can be found in a plenty amount in marine environments and is the secondly most abundant in nature, after cellulose. Mostly chitin is found in crustaceans, insects or other arthropods, also in mushrooms [1]. Chitin and chitin-derived products are attracting great interest because of their wide range of potential applications within biotechnology, medicine and pharmacology, agriculture, cosmetics, and wastewater treatment [2, 3, 4, 5]. In this study we investigated differences in the chitin content, physicochemical properties and surface morphology of chitins extracted from two common Baltic Sea shrimp species: Paleomon elegans and Crangon crangon. Both shrimp species are widely distributed along European coast and across the Atlantic east coast. The dry weight chitin contents P. elegans and C. crangon were determined as 7.1% and 6.7%, respectively. Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA) analysis were used to characterize physicochemical properties of obtained chitins. As expected, FT-IR and TGA results showed that the isolated chitins were in α form. The main difference between examined chitins extracted from two shrimp species was noticed after TGA. The first mass loss step for P. elegans was observed at 5.09% and the second mass loss step at 81.92%. For C. crangon the first mass loss was observed at 2.75% and the second mass loss at 65.39%. However, the highest decomposition temperature DTGmax were found to be the same for both species, 382.8 °C for P. elegans and 382.4 °C for C. crangon. The surface morphology of chitins yielded from two shrimp species were examined with scanning electron microscopy (SEM) and it revealed that these structures consists of nanofibers and nanopores, however chitin surface of C. crangon was rougher than P. elegans. [...]Biologijos katedraGamtos mokslų fakultetasVytauto Didžiojo universiteta