Extraction and characterization of chitin, chitosan and chitooligosaccharides from crab shell waste

Abstract

An experiment was carried out to utilize the crab shell waste for the production of chitin by chemical extraction method. The obtained chitin was processed to make the more useful compound chitosan by deacetylation of chitin using strong NaOH solution at high temperature. Yield of chitin and chitosan from crab shell waste was found to be 12.2 % and 10.54 %, respectively. Chitosan was further used to produce chito-oligosaccharides (COS) by acid hydrolysis using 0.5 N H 2 SO 4 , 1N H 2 SO 4 and 7N HCl at hourly intervals upto 6 hours and the average yield was 0.55, 0.84 and 1.93 mg/ml, respectively. Chitin and chitosan were characterized by Fourier Transform Infrared spectroscopy (FT-IR) technique which depicts different band representing various bonds present in the molecule and which were in agreement with the bands of standard chitin and chitosan. Further, COS were formed after acid hydrolysis of chitosan, which was characterized by Thin Layer Chromatography (TLC) using glucosamine as a standard.

Optimization of Chitin Extraction, Physicochemical and Functional Properties of Chitosan Production from Shells of Karamote Shrimp Peneaus (Melicertus) Kerathurus in Western Greece

“…In our experiment results of 1.0 N solution of HCl for demineralization, 2 N for deproteination and 12.5 N NaOH solutions for deacetylation at a solid to solvent ratio of 1:15, clearly demonstrate a significant yield of chitin and chitosan. Recovery of chitosan in the present study is similar to chitosan yield (15%) from shrimp shell waste reported by and slightly higher than yield of chitosan (12%) in study of [16,17].…”

A New Marine Biomaterial: The Shell of Mangrove Horseshoe Crabs, Carcinoscorpius rotundicauda (Latreille, 1802) Emphasizing Its Physico-Chemical Characteristics

“…While the peak of chitin on crab shells in the Sfax market, Tunisia was shown at 3447 cm −1 (O-H), 3,267-3,104 cm −1 (N-H stretching) and 2,929-2,882 cm −1 (asymmetrical and symmetrical C-H) (Hajji et al, 2015). The peak of chitin in crab shell samples from the Russel fish market, India was at 3,443 cm −1 (O-H stretching), 3,107 cm −1 (N-H stretching), 1,558 cm −1 (amide II), 1,314 cm −1 (amide III), 1,028 cm −1 (C-O stretching) (Varun et al, 2017). Another sign that the compound contains chitin are bending vibrations in the absorption of wave number 852-846 cm −1 , which indicates the presence of β-14-glycosidic bonds.…”

Chemoenzymatic Production and Engineering of Chitooligosaccharides and N-acetyl Glucosamine for Refining Biological Activities

“…Despite having numerous significant applications, the production routes of COS and GlcNAc are still in their infancy in terms of bio-sustainability. Currently, chemical processes are predominantly used for the production of COS and GlcNAc; however, degradation of product quality, generation of undesirable byproducts, and environmental concerns limits their application (Varun et al, 2017 ). Moreover, interest has been raised over enzymatic conversion (employing chitinase and/or N-acetyl glucosaminidase) of chitin and CHS to COS and GlcNAc that has the advantage of producing defined products with high specificity (Kumar et al, 2018a ).…”