title: Ionic liquids as novel solvents for biosynthesis of octenyl succinic anhydride-modified waxy maize starch.
abstract: Biosynthesis of octenyl succinic anhydride (OSA) starch was investigated using ionic liquids (ILs) as reaction media. Waxy maize starch was pretreated in 1-butyl-3-methylimidazolium chlorine and then esterified with OSA in 1-octyl-3-methylimidazolium nitrate by using Novozyme 435 as catalyst. The degree of substitution of OSA starch reached 0.0130 with 5 wt% starch concentration and 1 wt% lipase dosage based on ILs weight at 50 °C for 3h. The formation of OSA starch was confirmed by fourier transform infrared spectroscopy. Scanning electron microscopy and X-ray diffraction revealed that the morphology and crystal structure of starch were significantly destroyed. Thermogravimetric analysis showed that esterification decreased the thermal stability of starch. The successful lipase-catalyzed synthesis of OSA starch in ILs suggests that ILs are potential replacement of traditional organic solvents for starch ester biosynthesis.
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Li
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Xiwen
authors.initials: X
authors.lastname: Zhang
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China. Electronic address: yqtian@jiangnan.edu.cn.
authors.forename: Yaoqi
authors.initials: Y
authors.lastname: Tian
mesh_terms: D055162:Biocatalysis; D002175:Candida / Q000201:enzymology; D060326:Chemistry Techniques, Synthetic; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry*; D007700:Kinetics; D008049:Lipase / Q000378:metabolism; D013213:Starch / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D013696:Temperature; D014885:Waxes / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: C525963:1-butyl-3-methylimidazolium; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D007093:Imidazoles; D052578:Ionic Liquids; D014885:Waxes; C551966:octenyl succinic anhydride-modified starch; D013213:Starch; C093667:Novozyme 435; D008049:Lipase
keywords: Biosynthesis; Ionic liquids; OSA starch