title: Biocatalytic synthesis of starch esters by immobilized lipase on magnetic microparticles.
abstract: Enzymatic esterification is an efficient approach for modifying starch to functionalized biomaterials. In this study, conversion of cassava starch to fatty acid acyl esters using immobilized Thermomyces lanuginosus lipase on Fe3O4 microparticles modified with 3-aminopropyltriethoxysilane and covalently linked by 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide and N-hydroxysuccinimide (Fe3O4-AP-ED-lipase) in a solvent-free system was studied. An optimized reaction containing 5% w/v gelatinized starch, 1% v/v Triton X-100, and 1% w/v biocatalyst with 2.5% w/v of fatty acids (palmitic, oleic, or linoleic acid) resulted in esterified products with a degree of substitution (DS) of 0.12-0.14, while a slightly lower DS was observed using crude palm fatty acid distillate as the acyl donor with 42.9-59.6% recovery yield. Increasing DS led to lower glass transition temperature and higher viscosity of the esterified products. The enzyme showed high operational stability with 85% retaining in activity after recycling in three consecutive batches with simple separation by magnetization, leading to improved process economics.
authors.affiliation: a The Joint Graduate School for Energy and Environment , King Mongkut's University of Technology Thonburi , Bangmod, Bangkok 10140 , Thailand.
authors.forename: Nattanun
authors.initials: N
authors.lastname: Prasertpornsakun
authors.affiliation: a The Joint Graduate School for Energy and Environment , King Mongkut's University of Technology Thonburi , Bangmod, Bangkok 10140 , Thailand.
authors.forename: Marisa
authors.initials: M
authors.lastname: Raita
authors.affiliation: a The Joint Graduate School for Energy and Environment , King Mongkut's University of Technology Thonburi , Bangmod, Bangkok 10140 , Thailand.
authors.forename: Navadol
authors.initials: N
authors.lastname: Laosiripojana
authors.affiliation: b Enzyme Technology Laboratory , National Center for Genetic Engineering and Biotechnology , Khlong Luang , Pathum Thani 12120 , Thailand.
authors.forename: Verawat
authors.initials: V
authors.lastname: Champreda
mesh_terms: D001203:Ascomycota / Q000201:enzymology; D055162:Biocatalysis; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry*; D004951:Esterification; D004952:Esters / Q000737:chemistry; D008049:Lipase / Q000737:chemistry*; D013213:Starch / Q000096:biosynthesis* / Q000737:chemistry; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D004952:Esters; D013213:Starch; D008049:Lipase
keywords: cassava starch; fatty acid; immobilized lipase; magnetic microparticle; starch ester