Production of chitin and chitosan from shrimp shell wastes

Abstract

A method was developed for commercial scale production of chitin and chitosan in Bangladesh from marine shrimp, P. monodon and freshwater prawn, M. rosenbergii shell and appendages. Chitin is a macro-molecular linear polymer of anhydro N-acetyl glucosamine (N-Acetyl, 2-Amino 2-Deoxy DGlucose) and chitosan is deacetylated chitin. For production of chitin, fresh shells of P. monodon having initial bacterial load of >10 5 CFU/g sample and peroxide values of >10 mmol free iodine liberated /kg of oil were washed with dilute sulfuric acid. Adhered proteins were removed by washing with low strength alkaline solution and then rinsed with water. Crude chitin thus prepared was treated with concentrated hydrochloric acid and purified chitin was obtained after treating with low strength alkali solution. Water soluble chitosan was prepared by performing a deacetylation process using 50% NaOH (w/w) at 100 o C for 4-5 hours and then washed, dried and ground. For purification of chitin and chitosan, a series of experiments were conducted to optimize the level of NaOH concentration and time and temperature schedule of demineralization and deproteinization/deacetylation. A high temperature-short time schedule obtained best quality chitin and chitosan. Both subjective and objective methods were used for the testing of quality and purity of chitin and chitosan. Comparative studies between the quality of products from different components of the shell and from different shrimp/prawn species showed that both chitin and chitosan obtained from M. rosenbergii shell were better compared to those of P. monodon in terms of extractability, deacetylation, and color. Shells obtained better product compared to shrimp appendages. The study suggests that chitin and chitosan can be produced in existing shrimp/prawn processing plants of the country with the simple renovation.

Abated immune responses against recombinant hepatitis-b vaccine by chitin in mice

“…Chitin was extracted from the prawns using the method described by Islam et al (2016) 13) . The fresh frozen prawn shells were washed with hot water (95°C), dessicated and then pulverized.…”

Utilization of chitosan extracted from shrimp shell waste in wastewater treatment as low cost biosorbent

“…The method which used was adapted from the method of (S.Z. Islam, et.al., 2016) [18] with slight modification. It includes: extracting of chitin in two steps (demineralization of the grinded dry shrimp shells followed by deproteination of the demineralized product) then partial deacetilation of the produced chitin.…”

Chitosan films for regenerative medicine: fabrication methods and mechanical characterization of nanostructured chitosan films

“…It is a natural homopolymer of N-acetyl-D-glucosamine widely found in the exoskeletons of arthropods and insects and in crustacean shells as well as in fungi cell wall. From the controlled deacetylation of chitin, it is possible to obtain a copolymer of β(1-4)-linked N-acetyl-D-glucosamine and Dglucosamine subunits, called chitosan (Islam et al 2017). In nature, the extracted chitin is usually bound to proteins and minerals, which can be removed through processes of acidification and alkalization (Tapan Kumar and Bijaya 2018).…”