title: Synthesis of nanofiber-formable carboxymethylated Euglena-derived β-1,3-glucan.
abstract: Carboxymethylation of paramylon, a storage polysaccharide of Euglena, was explored using homogeneous and heterogeneous reaction systems. Homogeneous reactions yielded carboxymethyl paramylons with a low degree of substitution of carboxymethyl group (DScm) of ∼0.13. Heterogeneous reactions of paramylon with chloroacetic acid in a mixture of 2-propanol and a NaOH aqueous solution yielded carboxymethyl paramylons with a high DScm of up to ∼0.80. An essential step for successful carboxymethylation using the heterogeneous reaction systems devised in this study was the pretreatment of a paramylon particle to break its inherent highly crystalline state into an amorphous one. A high degree of substitution provided carboxymethyl paramylons with a nanofiber-forming ability in the aqueous phase while a low degree provided them with a fiber-forming ability in both the aqueous and solid phases.
authors: Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6th, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan. Electronic address: moto.shibakami@aist.go.jp.
authors: Motonari
authors: M
authors: Shibakami
authors: Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6th, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
authors: Gen
authors: G
authors: Tsubouchi
authors: Advanced Coating Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Central 5th, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
authors: Mitsugu
authors: M
authors: Sohma
authors: Department of Marine Biology and Environmental Science, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, Miyazaki 889-2192, Japan.
authors: Masahiro
authors: M
authors: Hayashi
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D000085:Acetates / Q000737:chemistry; D005055:Euglena / Q000737:chemistry*; D005936:Glucans / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000737:chemistry
chemical_list: D000085:Acetates; D005936:Glucans; C003045:paramylon; D012972:Sodium Hydroxide; C006972:chloroacetic acid; D019840:2-Propanol
keywords: Carboxymethylation; Euglena; Nanofiber; Paramylon; β-1,3-glucan