BioChem - DOS

Dissolution and deacetylation of chitin in ionic liquid tetrabutylammonium hydroxide and its cascade reaction in enzyme treatment for chitin recycling

Carbohydrate polymers

Ma, Qinyuan; Gao, Xiuzhen; Bi, Xinyu; Han, Qi; Tu, Linna; Yang, Yupeng; Shen, Yanbing; Wang, Min

<P><B>Abstract</B></P> <P>Chitin is the second most abundant renewable polymer on earth, and its deacetylated derivative, chitosan, is a highly useful biopolymer. This work studied for the first time the application of ionic liquid (IL) tetrabutylammonium hydroxide ([TBA][OH]) and chitin deacetylase from <I>Rhodococcus equi</I> CGMCC14861 (ReCDA) for the efficient conversion of chitin into chitosan at room temperature. Results confirmed that chitin had good solubility in 18 wt% aqueous [TBA][OH] solution at 80 &#8451;. In addition, efficient chitin deactylation was observed with high concentrations of [TBA][OH] exceeding 12 wt% and showing potential application in chitin conversion. ReCDA activity on chitin was activated by [TBA][OH] pretreatment. Sequential and simultaneous strategies were also compared, and the results showed that the simultaneous one-pot deacetylation provided the highest acetic acid yield of 3.78 mg/g chitin powder after 24 h. This study serves as a guide for the dissolution and deacetylation of chitin to produce high value-added chitosan products.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Mild ionic liquids [TBA][OH] was employed on chitin for the first time. </LI> <LI> [TBA][OH] showed dissolution and deacetylation abilities on chitin. </LI> <LI> Deacetylation of chitin was positively correlated with the solubility of chitin. </LI> <LI> A combinational process of [TBA][OH] pretreatment and ReCDA were performed. </LI> <LI> The ReCDA activity on chitin was activated with [TBA][OH] pretreatment. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

2020

Elsevier

0144-8617

230

pp.115605

10.1016/j.carbpol.2019.115605

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART98540468

Chitin; Dissolution; Deacetylation; Chitosan; Ionic liquid; Cascade reaction