In this study, we found that amylose–poly(tetrahydrofuran) (PTHF) inclusion complexes were formed when a mixture of amylose with PTHF was stirred in 1-butyl-3-methylimidazolium chloride of an ionic liquid at high temperature under reduced pressure, followed by cooling and precipitation by addition of methanol.

In this study, we found that amylose-poly(glycolic acid-co-e-caprolactone) (P(GA-co-CL)) inclusion complexes were formed when phosphorylase-catalyzed enzymatic polymerization was performed in the presence of biodegradable P(GA-co-CL)s according to a vine-twining polymerization process. The X-ray diffraction patterns of the products showed the typical diffraction peaks due to inclusion complexes composed of amylose and guest compounds. In addition, the 1 H NMR spectra of the products showed the signals due to amylose and P(GA-co-CL), in spite of washing with good solvents for P(GA-co-CL), such as acetone and chloroform. These results suggested that the products were inclusion complexes composed of amylose and P(GA-co-CL). The compositional ratio of GA unit to CL unit in P(GA-co-CL)s did not affect the inclusion behavior of amylose. On the other hand, the results in the vine-twining polymerization using amorphous P(GA-co-CL)s and a crystalline poly(glycolic acid-block-ecaprolactone) (P(GA-b-CL)) as guest polymers indicated that the crystallinity of the guest copolymers strongly affected the formation of inclusion complexes with amylose. In addition, we found that lipase-catalyzed hydrolysis of P(GA-co-CL) in the inclusion complex was partly inhibited, probably because amylose, which surrounded P(GA-co-CL), prevented the approach of lipase.

In this paper, we describe that amylose selectively includes poly(tetrahydrofuran) (PTHF) or poly(-valerolactone) (PVL) from a mixture of two resemblant polyethers, i.e., poly(oxetane) (POXT) and PTHF, or a mixture of two resemblant polyesters, i.e., PVL and poly("-caprolactone) (PCL) in vine-twining polymerization. These selective inclusions were achieved by the formation of amylose-polymer inclusion complexes in phosphorylase-catalyzed enzymatic polymerization of -D-glucose 1-phosphate from maltoheptaose as a primer in the presence of mixtures of POXT/PTHF and PVL/PCL, respectively. In addition, we evaluated the priority on inclusion of amylose toward these guest polymers in the vine-twining polymerization method to be PTHF > PVL > POXT > PCL.KEY WORDS: Amylose / Enzymatic Polymerization / Inclusion Complex / Phosphorylase / Vine-twining Polymerization / Biological macromolecules such as proteins, nucleic acids, and polysaccharides precisely discriminate various molecules in vivo, for example single strand of DNA recognizes homology in duplex one.1 Such a recognizability of the biomolecules has been often applied to discrimination of artificial compounds. For example, it has been reported that peptides recognized the specific structures of synthetic polymers. 2 We have also continuously been investigating the recognizability of amylose, a natural polysaccharide, toward synthetic polymers by means of its inclusion in amyloseforming polymerization field that is described as follows. 3Amylose has helical conformation linked through (1!4)--glycosidic linkages and is a well-known host compound that forms inclusion complexes with slender compounds having relatively lower molecular weight such as fatty acids by noncovalent interaction between guest molecules and the cavity of amylose. 4 However, little has been reported regarding the formation of inclusion complexes between amylose and polymeric compounds. 5 The main difficulty in incorporating polymeric compounds into the cavity of amylose is that the driving force for the binding is only caused by hydrophobic interactions. Amylose, therefore, does not have sufficient ability to include the long chains of guest polymers into its cavity.By means of the enzymatic method for direct construction of the polysaccharides, 6 we have developed a new methodology for the preparation of inclusion complexes composed of amylose and synthetic polymers, 3 which was achieved by the enzymatic polymerization forming amylose in the presence of guest polymers. The representation of this reaction system is similar to the way that vines of plants grow twining around a rod. Accordingly, we have proposed that this polymerization method for the preparation of amylose-polymer inclusion complexes is named ''vine-twining polymerization.'' As the guest polymers for this polymerization system, hydrophobic polyethers, 3a,c polyesters, 3b,d,i a poly(esterether), 3d and polycarbonates 3h have been employed to form the corresponding inclusion complexes with amylose. On the basis of the results in ...

In this paper, we describe the preparation of hydrogels through the formation of an inclusion complex of amylose in a vine-twining polymerization. This is achieved by the phosphorylase-catalyzed polymerization of alpha-D-glucose 1-phosphate from maltoheptaose primer, in the presence of a water-soluble copolymer having hydrophobic graft-chains (poly(acrylic acid sodium salt-graft-delta-valerolactone)). The mixture turns into a gel during the polymerization process. Evaluation of the hydrogels is conducted by shear-viscosity measurements of the products. For the hydrogels with relatively high viscosities, fast relaxation modes of the cooperative diffusions are observed by scanning microscopic light scattering measurements, which indicate the nanometer-size network structures of the hydrogels. In addition, we found that the enzymatic disruption and reproduction of the hydrogels are achieved by the combination of the amylase-catalyzed hydrolysis of the amylose component and the formation of amylose by the phosphorylase-catalyzed polymerization.

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