Optimizing Extraction of Cellulose and Synthesizing Pharmaceutical Grade Carboxymethyl Sago Cellulose from Malaysian Sago Pulp

Abstract

Abstract:Sago biomass is an agro-industrial waste produced in large quantities, mainly in the Asia-Pacific region and in particular South-East Asia. This work focuses on using sago biomass to obtain cellulose as the raw material, through chemical processing using acid hydrolysis, alkaline extraction, chlorination and bleaching, finally converting the material to pharmaceutical grade carboxymethyl sago cellulose (CMSC) by carboxymethylation. The cellulose was evaluated using Thermogravimetric Analysis (TGA), Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Field Emission Scanning Electronic Microscopy (FESEM). The extracted cellulose was analyzed for cellulose composition, and subsequently modified to CMSC with a degree of substitution (DS) 0.6 by typical carboxymethylation reactions. X-ray diffraction analysis indicated that the crystallinity of the sago cellulose was reduced after carboxymethylation. FTIR and NMR studies indicate that the hydroxyl groups of the cellulose fibers were etherified through carboxymethylation to produce CMSC. Further characterization of the cellulose and CMSC were performed using FESEM and DSC. The purity of CMSC was analyzed according to the American Society for Testing and Materials (ASTM) International standards. In this case, acid and alkaline treatments coupled with high-pressure defibrillation were found to be effective in depolymerization and defibrillation of the cellulose fibers. The synthesized CMSC also shows no toxicity in the cell line studies and could be exploited as a pharmaceutical excipient.

Effect of Carboxymethyl Cellulose on the Mechanical and Barrier Properties of Sago Starch Based Films

“…Adding carboxymethyl cellulose improved starch network so that starch could form hydrogenous bond with hydroxyl and carboxyl groups of carboxymethyl cellulose macromolecules, leading to reinforcement of structure and reduction in diffusion of water molecules through starch network. Similar results were also obtained by other researchers who observed reduction of water absorption by polymeric mixtures and bio-composites via adding cellulose-hemicellulose fibers [1,5,13,16]. Increased concentration of carboxymethyl cellulose reduced humidity absorption of composite films.…”

“…Other researchers investigated effect of calcium chloride on physical and mechanical properties of alginate-sago edible films. Increased concentration of calcium chloride increased tensile strength of alginate-sago edible films but increased elongation percent of these films [1,5,10,13].In some cases, reported that adding carboxymethyl cellulose to soy protein film could improve mechanical properties of these films due to reaction and connection between polymeric chains of protein [14,15]. Parra et al conducted studies on mechanical properties of edible films caused by cassava starch.…”

“…Although sago has its unique characteristics, some of its features are like those of cassava and potato. It is a complicated starch grain size with diameter of 30 µm and humidity of 0.32%-0.26%, which can produce an appropriate film [1]. The water friendly feature of starch and weak resistance of the film toward any humidity and weaker mechanical feature compared to synthetic polymers are the most important weaknesses of starch which limit its use [10].…”

“…During recent years, finding an alternative for sanitizing plastics which bears less environmental pollution has attracted experts' attention. Using recoverable agricultural resources is recommended for protecting the environment [1][2][3][4]. Bio polymers which are a good potential for replacing sanitized packaging materials are called green materials because of being environmentally friendly [1,3,5,6].…”

“…Using recoverable agricultural resources is recommended for protecting the environment [1][2][3][4]. Bio polymers which are a good potential for replacing sanitized packaging materials are called green materials because of being environmentally friendly [1,3,5,6]. Films refer to very thin layers that are made of food products and used as food coatings, polysaccharides protein and fat or their combination [6].…”