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

Šiame tyrime chitinas buvo išskirtas iš dviejų Baltijos jūroje gyvenančių krevečių rūšių (Paleomon elegans ir Crangon crangon). Tyrimo metu buvo nustatytas chitino kiekis, išanalizuotos fizikocheminės chitinų savybės bei chitinų paviršiaus morfologijos struktūra. Sausoje P. elegans masėje chitino kiekis sudarė 7,1%, C. crangon – 6,7% Kaip ir tikėtasi Furjė infraraudonųjų spindulių spektroskopijos (FTIR), termogravimetrinės (TGA) bei Rentgeno spindulių difrakcijos analizės rezultatai atskleidė, kad abiejų krevečių chitinai yra α formoje. Esminis skirtumas tarp tirtų chitinų buvo pastebėtas atlikus TGA. Pirmojo masės netekimo etapo metu (0 – 150 °C) chitnas išskirtas iš P. elegans neteko 5,09% masės, o antorojo etapo metu (150 – 400 °C) 81,92%, tuo tarpu C. crangon pirmojo etapo metu neteko 2,75%, o antorojo 65,39% masės. Tačiau maksimali degradacijos temperatūra (DTGmax) tarp P. elegans ir C. crangon chitinų buvo vienoda 382,8 °C ir 382,4 °C. Paviršiaus struktūra tirkra skenuojančiuoju elektronų mikroskopu (SEM) buvo panaši tarp abiejų tirtų krevečių rūšių chitinų. Chitinų paviršiaus struktūra buvo sudaryta iš tankiai tarpusavyje susipynusių nanogijų bei nanoporų. Tačiau chitino išskirto iš C. crangon paviršius buvo šiurkštesnis. Atsižvelgiant į šio tyrimo rezultatus matyti, kad chitinai yra termiškai stabilūs, jie gali būti naudojami industriniams tikslams. Tuo labiau, skaidulinė tirtų krevečių chitinų struktūra yra tinkama tekstilės pramonei ir biomedicinai. Be to, šis tyrimas įrodo, kad Baltijos jūra yra naujas ir neišnaudotas chitino šaltinis Šiaurės Europoje.In this study chitin was extracted from two Baltic Sea shrimp species (Paleomon elegans and Crangon crangon). The differences in the chitin content, physicochemical properties and surface morphology of extracted chitins were investigated. The dry weight of chitin contents of P. elegans and C. crangon were determined as 7.1% and 6.7%, respectively. Fourier transform infrared spectroscopy (FTIR), thermogravimetric (TGA) and X-ray diffraction analysis were used to characterize physicochemical properties of obtained chitins. As expected, 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. At the first thermal decomposition step for P. elegans mass loss was observed 5.09% and at the second mass loss step – 81.92%. For C. crangon the first mass loss was 2.75% and the second mass loss was 65.39%. However, the highest decomposition temperature (DTGmax) was 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. According to our results the extracted chitin was thermally stable and can be found widely applicable in many industrial processing. Also, fibril structure of chitins suggested that it is suitable for using in textile industry and biomedicine. Furthermore, we believe that the Baltic Sea is a new and unexploited source of chitin in Northern Europe.Gamtos mokslų fakultetasVytauto Didžiojo universiteta

Diversity and composition of terestrial isopods (Crustacea: Isopoda) in Kaunas city

Woodlice/terrestrial isopods are very widespread, quite easily identified crustaceans. They form a dominant component of the soil arthropod macro decomposer community in many different temperate habitats, like denes, pine forests, decidous forests, riversides, even in moist cellars. They feed on dead organic material and are key system regulators of the ecosystem functions of decomposition and nutrient recycling. Woodlice diversity was studied in five different biotopes in Kaunas city: mixed forest, leafy forest/park, coniferous wood/forest, grassland and anthropogenic area. All specimens were collected by pitfall trapping (also woodlice can be sampled be hand or extracted soil by heat and light). Over all 3 species of woodlice were found in choosen habitats .The number of isopods, which were collected during the exploration was —1251. The highest diversity was identified in mixed woodlands, there were found 2 species of woodlice, T.rathkii, P. scaber, not so high at pine forest compared with meadow, and no woodlice was collected at leafy forest/park. Porcellio scaber was abundant at all biotopes. Woodlice are also significant as bioindicators, like bioaccumulators of heavy metals, that’s why exploration af these crustaceans is important aimBiologijos katedraGamtos mokslų fakultetasVytauto Didžiojo universiteta

Preliminary study on the terrestrial isopods of Kaunas city (Lithuania)

ISSN 2165-8013 (Online)The present study contains the results of a study on terrestrial isopod (Crustacea: Isopoda: Oniscidea) samples collected by pitfall traps from five different habitats during four different months in different seasons (late spring, early summer, early autumn, and late autumn) during 2012. All sampling plots were located in Kaunas city. As a result, three species were identified: Trachelipus rathkii (Brandt, 1833), Porcellio scaber (Latreille, 1804), and Oniscus asellus (Linnaeus, 1758). All species found had previously been known from Lithuania. T. rathkii, a eurytopic species, dominated in all studied habitats. Low species richness and diversity might be due to a selective nature of the sampling method. Abundance (surface activity) showed a seasonal pattern. The sample size of the superdominant T. rathkii allowed calculating a temporal sex ratio for this species: females dominated in all habitats and in almost all periodsBiologijos katedraGamtos mokslų fakultetasVytauto Didžiojo universiteta

A physicochemical characterization of chitin extracted from edible Lithuanian mushrooms

Chitin is a biopolymer made from (1→4)-linked N-acetyl-β-D-glucosamine. It can be found in exoskeleton of crustacean, insect and in the cell wall of mushrooms [1]. Chitin is very important biomaterial these days, because of its biodegradable, biocompatible, nontoxicity, antitumor, antioxidant and antimicrobial properties. Chitin has many applications in medicine, cosmetic, biotechnology and other fields [2]. More than 100 000 mushrooms species are known in the World. More than 6000 mushrooms species are described in Lithuania [3]. Till now no studies has been done with Lithuanian mushrooms chitin. In this study the Lithuanian mushrooms chitin was investigated for the first time. The aims of this study were: a) to extract chitin from five edible mushrooms species belonging to four families; b) to evaluate and compare chitin physicochemical properties between these five mushrooms, c) to compare chitin contents of mushroom pileus and stipes. Chitin was extracted from five (Boletus edulis, Leccinum auranticum, Russula vesca, Cantharellus cibarius and Paxillus involtus) edible Lithuanian mushrooms by using a chemical method. Four steps was used to isolate chitin from mushrooms: mushrooms dust bleaching (NaClO), deproteinization (NaOH), demineralization (HCl) and second deproteinization (NaOH). Obtained chitin was characterized by Fourier transform infrared spectroscopy (FTIR) and by scanning electron microscopy (SEM). The results of FTIR showed that all mushrooms chitin are in alpha form and can be used as a potential raw material for chitin production. SEM analysis showed that mushrooms chitin surface was clumped and has no clearly visible nanoporous and nanofibers structure. The chitin contents of pileus and stipes of mushroom bodies were determined and compared. Three mushrooms species (Leccinum auranticum, Cantharellus cibarius, Paxillus involtus) out of total five had higher chitin content in pileus [...]Biologijos katedraGamtos mokslų fakultetasVytauto Didžiojo universiteta

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

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

Differentiations of chitin content and surface morphologies of chitins extracted from male and female grasshopper species

WOS: 000350680700013PubMed: 25635814In this study, we used Fourier transform infrared spectroscopy (FT-IR), elemental analysis (EA), thermogravimetric analysis (TGA), X-ray diffractometry (XRD), and scanning electron microscopy (SEM) to investigate chitin structure isolated from both sexes of four grasshopper species. FT-IR, EA, XRD, and TGA showed that the chitin was in the alpha form. With respect to gender, two main differences were observed. First, we observed that the quantity of chitin was greater in males than in females and the dry weight of chitin between species ranged from 4.71% to 11.84%. Second, using SEM, we observed that the male chitin surface structure contained 25 - 90nm wide nanofibers and 90 - 250 nm nanopores, while no pores or nanofibers were observed in the chitin surface structure of the majority of females (nanofibers were observed only in M. desertus females). In contrast, the elemental analysis, thermal properties, and crystalline index values for chitin were similar in males and females. Also, we carried out enzymatic digestion of the isolated chitins using commercial chitinase from Streptomyces griseus. We observed that there were no big differences in digestion rate of the chitins from both sexes and commercial chitin. The digestion rates were for grasshoppers' chitins; 88.45-95.48% and for commercial chitin; 94.95%

Differentiations of chitin content and surface morphologies of chitins extracted from male and female grasshopper species

Gamtos mokslų fakultetasVytauto Didžiojo universiteta

FT-IR spectra of the α-chitin isolated from female and male of five grasshopper species.

<p>a) <i>Celes varabilis</i> female, b) <i>C. varabilis</i> male, c<i>) Dectius verrucivorus</i> female, d) <i>D. verrucivorus</i> male, e) <i>Melanogryllus desertus</i> female, f) <i>M. desertus</i> male, g) <i>Paracyptera labiata</i> female, h) <i>P. labiata</i> male.</p

Localities of the grasshopper species collected from Turkey.

<p>Localities of the grasshopper species collected from Turkey.</p

Results of elemental analyses (EA) and degree of acetylation (DA).

<p>Results of elemental analyses (EA) and degree of acetylation (DA).</p