Abdelghani Hassainia¹, Hamid Satha^1,*, Boufi Sami²

Journal of Renewable Materials, Vol.8, No.1, pp. 101-111, 2020, DOI:10.32604/jrm.2020.07725

Abstract Two methods were used to produce chitosan by deacetylation of chitin which was extracted from Agaricus bisporus stipes. The first one gives chitosan 1 with low yield of 2.5%, degree of acetylation (DA) of 4%, molecular weight (MW) of 2.973 × 10⁵ (g/mol). The second route produces chitosan 2 with higher yield of 41%, degree of acetylation (DA) of 17.23%, molecular weight (MW) of 2.939 × 10⁵ (g/mol). Both chitosans were characterized by XRD, FTIR, ¹ H-NMR spectroscopy nuclear magnetic resonance of proton. The molecular weight (M_W) was determined by size exclusion chromatography (SEC). Thermal analysis shows that both chitosans… More >

Yan PM¹, HF Zhang¹, Q Wang¹, XY Yan¹, Y Sun²

Phyton-International Journal of Experimental Botany, Vol.79, pp. 117-121, 2010, DOI:10.32604/phyton.2010.79.117

Abstract Isozymes of peroxidase (POD), catalase (CAT), esterase (EST) and superoxide dismutase (SOD) were analyzed on transgenic maize (with external chitinase gene) and its parent by vertical polyacrylamide gel electrophoresis (PAGE). This study was made using shoots at the fourth leaf stage. Results showed that: POD and EST were detected in 6 bands. POD-2 and POD-3 were present at the bud and seedling stages. POD-1, POD-4, POD-5 and POD-6 were only present at the seedling stage. POD-6 expressed stronger in the transgenic maize with chitinase than in its parent. EST-2 was present only at the bud stage, and its expression in… More >

González-Franco AC¹, L Robles-Hernández¹, JL Strap²

Phyton-International Journal of Experimental Botany, Vol.86, pp. 14-27, 2017, DOI:10.32604/phyton.2017.86.014

Abstract The Streptomyces genus comprises a large and diverse group of bacteria, many of which are commercially exploited for the production of antibiotics and lytic enzymes. The thermophilic species are less studied than the predominant mesophilic species. However, the first ones are a potential source of thermostable bioactive products and enzymes with novel properties. In this study, two selected thermophilic streptomycetes were identified and their chitinolytic activities were evaluated. The identification of these two isolates was performed by microscopic morphology, partial 16S rDNA sequences, and its phylogenetic analysis. To study the chitinolytic activities of these isolates, the effects of colloidal chitin… More >

Murat Kaya^1,*, Idris Sargin¹, Povilas Mulerčikas², Jalel Labidi³, Asier M. Salaberria³, Yavuz S. Cakmak¹, Sonata Kazlauskaitė², Demet Erdonmez⁴, Vykintas Baublys⁵

Journal of Renewable Materials, Vol.7, No.3, pp. 215-226, 2019, DOI:10.32604/jrm.2019.00002

Abstract Hylobius abietis is a plant parasitic insect belonging to the order Coleoptera and which causes severe damages to coniferous forests in Northern and Eastern Europe. This current study is aimed to provide a new viewpoint into the waste of this insect by producing chitosan. Dry insect corpses consisted of 27.9% chitin and 86.2% of the chitin was converted into the chitosan. FT-IR spectra analyses confirmed the purity and the deacetylation degree of the produced chitosan (molecular weight of chitosan; 7.3 kDa). This chitosan exhibited antimicrobial activity against 18 bacterial strains. Further, biodegradable chitosan composite films with β-carotene were produced. Antioxidant… More >

Miguel Ángel Ramírez¹, Patricia González², Juan Reinerio Fagundo², Margaret Suarez³, Clara Melian³, Tania Rodríguez¹, Carlos Peniche^4*

Journal of Renewable Materials, Vol.5, No.1, pp. 30-37, 2017, DOI:10.7569/JRM.2016.634121

Abstract The inorganic components of crustacean shells are usually removed using HCl solutions. This provokes undesirable modifications in the extracted chitin. In the present procedure, deproteinized lobster shells were demineralized with CO2 and a cationic resin (cationite). The resulting chitin (CHI-CO2) is compared in terms of degree of acetylation (DA), crystallinity index (CrI) and thermal stability with chitins obtained by demineralization procedures with HCl (CHI-HCl) and ethylenediaminetetraacetic acid (CHI-EDTA). The ash content of chitins demineralized with CO2 was similar to that of chitins prepared using HCl or EDTA. However, the resultant DA and CrI of CHI-HCl and CHI-EDTA were lower than… More >