The influence of papain concentration on deacetyllation degree of chitin

The study on the effect of papain enzyme concentration on chitin preparation from shrimp shells has been conducted. This study was conducted as optimization stage of enzyme concentration against the degree of deacetylation of chitin produced. Chitin preparation was performed using combination of chemical processes through demineralization of chitin with dilute hydrochloric acid followed by deproteinization using papain enzyme with variation of 0-25% papain concentration. Characterization and determination of deacetylation degree were done using infrared spectrophotometry. The infrared spectra indicate characteristic for functional group of chitin. Vibration at around 3450 cm⁻¹ showed an aliphatic -OH group on a glucosamine ring in chitin. Strong absorption at around 1655 cm⁻¹ shows the stretching vibrations of the C=O group. Weak uptake in the range of 2930 cm⁻¹ shows the vibration of stretching C-H. Uptake in the region of 1070 cm⁻¹ and 1150 cm⁻¹ shows the presence of stretching vibration C-O. The stretching vibrations for C-N and N-H groups in acetyl groups is indicated on wave numbers 1070 cm⁻¹ and 1380 cm⁻¹. Based on the results of the study it can be shown that papain can function as hydrolase enzyme in chitin deproteination reaction. Papain concentration may increase the degree of deacetylation of chitin. The optimum data can be obtained in the deproteinization of chitin with 25% papain which can provide deacetylation degrees of 41.07 ± 2.21%.