TY - JOUR
T1 - Immobilization of enzyme cocktails on dopamine functionalized magnetic cellulose nanocrystals to enhance sugar bioconversion
T2 - a biomass reusing loop
AU - Ariaeenejad, Shohreh
AU - Motamedi, Elaheh
AU - Hosseini Salekdeh, Ghasem
PY - 2021/3/15
Y1 - 2021/3/15
N2 - A combined enzymatic treatment/acid hydrolysis technique was utilized to synthesize cellulose nanocrystals (CNCs) from sugar beet pulp. CNCs were functionalized with magnetite nanoparticles and dopamine making a versatile nano-carrier (DA/Fe3O4NPs@CNCs) for covalent enzyme immobilization. Oxygene/amine functionalities, high magnetization value, and specific surface area of DA/Fe3O4NPs@CNCs made it a reusable and green candidate for conjugation to hydrolytic enzyme cocktails (three cellulases, two hemicellulases, and their combinations) to prepare an innovative and practical nano-biocatalyst for biomass conversion. The conjugated enzymes showed an enhanced optimum temperature (∼ 10 °C), improved thermal stability, and shifted optimum pH toward alkaline pHs. Covalent attachment could successfully suppress the enzyme leaching and provide easy recovery/reuse of the nano-biocatalyst up to 10 cycles, with > 50% of initial activity. Application of the nano-biocatalyst in hydrolysis of rice straw and sugar beet pulp showed an increase (20-76%) in the yield of fermentable sugars compared to the free enzyme cocktails.
AB - A combined enzymatic treatment/acid hydrolysis technique was utilized to synthesize cellulose nanocrystals (CNCs) from sugar beet pulp. CNCs were functionalized with magnetite nanoparticles and dopamine making a versatile nano-carrier (DA/Fe3O4NPs@CNCs) for covalent enzyme immobilization. Oxygene/amine functionalities, high magnetization value, and specific surface area of DA/Fe3O4NPs@CNCs made it a reusable and green candidate for conjugation to hydrolytic enzyme cocktails (three cellulases, two hemicellulases, and their combinations) to prepare an innovative and practical nano-biocatalyst for biomass conversion. The conjugated enzymes showed an enhanced optimum temperature (∼ 10 °C), improved thermal stability, and shifted optimum pH toward alkaline pHs. Covalent attachment could successfully suppress the enzyme leaching and provide easy recovery/reuse of the nano-biocatalyst up to 10 cycles, with > 50% of initial activity. Application of the nano-biocatalyst in hydrolysis of rice straw and sugar beet pulp showed an increase (20-76%) in the yield of fermentable sugars compared to the free enzyme cocktails.
KW - Cellulose nanocrystals
KW - Magnetic nano-carrier
KW - Dopamine
KW - Enzyme cocktail
KW - Covalent immobilization
KW - Biomass conversion
UR - http://www.scopus.com/inward/record.url?scp=85098563399&partnerID=8YFLogxK
U2 - 10.1016/j.carbpol.2020.117511
DO - 10.1016/j.carbpol.2020.117511
M3 - Article
C2 - 33483032
AN - SCOPUS:85098563399
SN - 0144-8617
VL - 256
JO - Carbohydrate Polymers
JF - Carbohydrate Polymers
M1 - 117511
ER -