Xiaoliang Zhao^1,#, Yuting Wang^1,#, Xiuying Pu¹, Jianzhong Ma¹, Feifan Leng¹, Yonggang Wang¹, Yanling Wang¹, Shuhong Yang¹, Fen Ran², Weijie Zhang^1,*

Journal of Renewable Materials, Vol.7, No.12, pp. 1321-1332, 2019, DOI:10.32604/jrm.2019.07757

Abstract A series of the Guiqi polysaccharides/chitosan/alginate composite hydrogel microspheres (GPcM) with different particle sizes were prepared with Guiqi polysaccharides (GP), chitosan (CS) and sodium alginate (Alg). The optimum preparation process was also determined by single factor and orthogonal experiment analysis. The GPcM were characterized by fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), drug loading efficiency test (LE), encapsulation efficiency test (EE) and in vitro release study. The results showed that the Guiqi polysaccharides chitosan hydrogel (GPCH) and sodium alginate hydrogel (SAH) formed a crossover system in GPcM. The GPcM have a uniform particle More >

Malinda Syifa Yusharani, Stenley, Harmami, Ita Ulfin, Suprapto Suprapto, Yatim Lailun Ni’mah*

Journal of Renewable Materials, Vol.7, No.7, pp. 643-653, 2019, DOI:10.32604/jrm.2019.04185

Abstract Water-Soluble Chitosan (WSC) has been sucessfuly synthesized from squid pens waste. The synthesis of chitosan from chitin was carried out by optimization of deacetylation temperature and time. Chitin was obtained from squid pens waste by demineralization and deproteinization process. HCl 7% was used for demineralization and NaOH 10% at 60°C was applied for deproteinization process. Deacetylation reaction was carried out at varied temperatures i.e., 60°C, 70°C, 80°C, 90°C and 100°C in NaOH 50% solution for 10 hours. Deacetylation reaction time were varied for 2 hours, 4 hours, 6 hours, 8 hours, and 10 hours. The… More >

Abeer M. Adel¹, Amira M. El-Shafei², Atef A. Ibrahim¹, Mona T. Al-Shemy^1,*

Journal of Renewable Materials, Vol.7, No.6, pp. 567-582, 2019, DOI:10.32604/jrm.2019.00034

Abstract In this study, nanocrystalline celluloses were used to enhance physical, mechanical and water vapor barrier properties of chitosan films for potential food packaging applications. Two different mineral acids (sulfuric and phosphoric) were used to extract nanocrystalline cellulose from date palm sheath fibers. The influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses (e.g., yield, energy and length of intra- and intermolecular hydrogen bonds, and degree of substitution) were studied too. The characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline cellulose. Results 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 More >

Victor Gomes Lauriano Souza¹, Patrícia Freitas Rodrigues², Maria Paula Duarte¹, Ana Luísa Fernando^1*

Journal of Renewable Materials, Vol.6, No.5, pp. 548-558, 2018, DOI:10.7569/JRM.2018.634104

Abstract The aim of this work was to develop an active biopolymer based on chitosan by incorporating natural antioxidants. Five essential oils (ginger, rosemary, sage, tea tree and thyme) and six hydro-alcoholic extracts (from ginger, green and black tea, kenaf leaves, rosemary and sage plants) were tested. Migration assays were carried out to evaluate the films' activity, and total phenolic content and antioxidant activity were monitored in the simulant during storage. Interaction between natural compounds and polymeric matrix was evaluated by FTIR spectroscopy. The diffusion of the phenolic compounds was not detected in the films incorporated More >

Min Fan^1,2,3*, Qiaoling Hu⁴

Journal of Renewable Materials, Vol.6, No.5, pp. 457-463, 2018, DOI:10.7569/JRM.2017.634178

Abstract The absorption behavior of chitosan in alkaline solution by freeze-blasting was studied. The influence of alkaline type, concentration, and small molecules was investigated, as well as the different roles of LiOH and NaOH in the absorption. Chitosan reached its maximum absorption rate when LiOH concentration was 4.8 wt% and NaOH 4.0 wt%, respectively. Chitosan showed better absorption capacity in LiOH solution. Urea could improve the absorption when its concentration was more than or equal to 4.0 wt%, and the improvement was greater in NaOH solution. Thiourea showed no obvious effect in LiOH solution, but showed More >

David Azria^1,2, Raluca Guermache^1,2, Sophie Raisin¹, Sébastien Blanquer¹, Frédéric Gobeaux³, Marie Morille¹, Emmanuel Belamie^1,2,*

Journal of Renewable Materials, Vol.6, No.3, pp. 314-324, 2018, DOI:10.7569/JRM.2017.634186

Abstract Biopolymers extracted from renewable resources like chitosan and collagen exhibit interesting properties for the elaboration of materials designed for tissue engineering applications, among which are their hydrophilicity, biocompatibility and biodegradability. In many cases, functional recovery of an injured tissue or organ requires oriented cell outgrowth, which is particularly critical for nerve regeneration. Therefore, there is a growing interest for the elaboration of materials exhibiting functionalization gradients able to guide cells. Here, we explore an original way of elaborating such gradients by assembling particles from a library of functionalized microspheres. We propose a simple process to 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… More >

Arun Kumar Pradhan^1,2*, Prafulla Kumar Sahoo¹, Pradeep Kumar Rana²

Journal of Renewable Materials, Vol.5, No.5, pp. 371-379, 2017, DOI:10.7569/JRM.2017.634129

Abstract Chitosan grafted with poly(methyl-methacrylate) (PMMA) and adsorbed with kaolin functionalized as bioadhesive was prepared via emulsion polymerization technique and physiochemically characterized as a bone-graft substitute. The so prepared grafted bioactive bone cement (BBC) bionanocomposites (BNCs), chitosan-g-PMMA/kaolin, was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, field-emission scanning electron microscopy (FESEM) and thermogravimetric analysis (TGA). The water uptake, retention ability and the nanosize particle arrangement in the polymeric BBC-BNCs were studied along with the mechanical and biodegradation properties. These preliminary investigations of the BNCs will open the door for their use in bioadhesive More >

Hilary Ureña-Saborío^1*, Sergio Madrigal-Carballo¹, Jorge Sandoval², José R. Vega-Baudrit³, Alejandro Rodríguez-Morales²

Journal of Renewable Materials, Vol.5, No.3-4, pp. 290-299, 2017, DOI:10.7569/JRM.2017.634119

Abstract Currently there is a trend towards reducing the use of agrochemicals in developing countries. However, they are still being applied intensively in tropical countries. Thus, there is a trend towards developing new products based on natural chemicals for pest control, leading to second-generation pesticides incorporating nano- and biotechnologies. Costa Rica is one of the largest producers of bananas in the world. One of the most important pests of banana and plantain crops is the burrowing nematode, Radopholus similis (Cobb) Thorne. Highly toxic chemical compounds have traditionally been used to control this specific pest in banana… More >