A comparison of chitosan properties after extraction from shrimp shells by diluted and concentrated acids

Abstract

Chitosan and chitin are mainly extracted from shells of fish such as lobsters, crabs or shrimps. Originally, the raw material and the two compounds are identical. This study aims to show the acid concentration effect on chitosan extraction from shrimp shells between concentrated and diluted acid; on surface morphology, thermal resistance, structural, elemental composition, optical and opto-electronic properties. It also aims to reduce the production time and increase the quantity. We focused mainly on comparing between Physico-chemical properties of chitosans extracted by diluted (1M) and concentrated (20%) Chloric acids, and sometimes we compare by other concentrated acids like nitric acid (70%) and sulphuric acid (98%). We performed the product's characterization by various tools such as: X-ray diffraction (XRD) spectroscopy, X-ray fluorescence (XRF) analysis, UV-Visible spectroscopy, Fourier Transformed Infra-Red (FTIR), Raman Spectroscopy, Thermogravimetry and Derivative Thermogravimetry (TG/DTG), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX) analysis. The elemental analysis (XRF and EDX). The results showed that all chitosan samples we gained are good about 80% degree of deacetylation, and pure mostly composed by carbon between (15,02% -45.55%), nitrogen (4,17% -12.28%) and oxygen (42.16% and 81.25%), with appearance of essential peaks for chitosan in Raman analysis: 470 cm À1 → ν(C-C(¼O)-C), 1000 cm À1 → ν(C-H), 1800 cm À1 → δ(C¼CCOOR), δ(C¼O), 2630 cm À1 → δ(CH) rings, 3250 cm À1 → ν(NH 2 ). All our chitosan particles are ultrafine nanoscale between 8 and 34 nm.

Application of Raman Spectroscopic Imaging to Assess the Structural Changes at Cell-Scaffold Interface

“…The band at 495 cm −1 is assigned to CO-NH out-of-plane and C-CH 3 in-plane bending. Pyranoid ring is characterised by presence of out-of-plane bending at 424 and 356 cm −1 [ 27 , 28 ].…”

Exploring the potential of highly efficient graphite/chitosan–PVC composite electrodes in the electrochemical degradation of Reactive Red 4

“…S10 (a) shows two distinct peaks at 2⊔ of 26.5°and 54.6°which corresponded to two crystallographic planes of (0 0 2) and (0 0 4), respectively, that has been reported for graphite (PDF 00-008-0415) on the electrode surface. 61,62 Chitosan (PDF 00-039-1894) was represented by a peak at diffraction angle near to 2⊔ = 20.2°6 2 whereas PVC (PDF 00-062-1710) appeared at 2⊔ = 17.7°. 63 The graphite showed the highest percentage of 97.84%, Chi 0.46% and PVC 1.70%.…”

Recent progress in the conversion of biomass wastes into functional materials for value-added applications

“…During 2016–2017, the production of fish in India was up to 11.41 Mt, and 70% marine fish were processed before final sale, which left 20–80% fishing wastes [ 42 ]. In 2006, the total worldwide generation of shrimp reached 6 Mt, but only 60% were used as food, creating about 2.3 Mt of inedible wastes [ 43 ]. They were discarded nearby harbor or at the sea and were broken down by the aerobic bacteria living in the sea, resulting in the relative reduction of oxygen level under the sea [ 42 ].…”

“…Chitin and chitosan are commonly found in crustaceans, insects, and microorganisms [ 43 ]. Among them, the shells of crustaceans such as shrimp, crab, and lobster are the most significant sources.…”

“…In addition, the percentage chitin yields from biomass wastes through this new method were in the range of 13–14%, which were very similar to the previously reported yields by conventional way (10–20%). Eddya et al [ 43 ] investigated the effect of acid concentration on the chitosan extraction efficiency from shrimp shell. The result showed that chitosan obtained from concentrated acid and base treatment was highly pure with the degree of deacetylation of 80% and had better heat resistance compared with commercial chitosan.…”