title: A novel capsule-like structure of micro-sized particles formed by phytosterol ester and γ-cyclodextrin in water.
abstract: The composite material formed by phytosterol ester (PSE) and γ-cyclodextrin (γ-CD) disperses readily in water and has been used to mask undesirable flavours. This paper elucidates the structure of the PSE/γ-CD particle. Cryogenic scanning electron microscopy and contact angle measurements showed that the PSE/γ-CD particles formed a capsule-like structure with a hydrophilic surface. A phase-solubility study using cholesteryl oleate (ChO), one of the components of PSE, showed that ChO formed a hydrophilic and stoichiometric inclusion complex with γ-CD at a molar ratio of 2:5. The structure of the PSE/γ-CD inclusion complex was similar to that of ChO/γ-CD, based on differential scanning calorimetry and powder X-ray diffractometry results. Thus, we propose that the PSE/γ-CD particle has a capsule-like structure wherein a hydrophobic PSE droplet is surrounded by an outer layer of the hydrophilic PSE/γ-CD inclusion complex.
authors.affiliation: Central Research & Development Institute, House Foods Group Inc., 1-4, Takanodai, Yotsukaido-shi, Chiba 284-0033, Japan. Electronic address: h-sasako@housefoods.co.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sasako
authors.affiliation: Research & Development Institute, House Foods Corporation, 1-4, Takanodai, Yotsukaido-shi, Chiba 284-0033, Japan.
authors.forename: Fukashi
authors.initials: F
authors.lastname: Kihara
authors.affiliation: Central Research & Development Institute, House Foods Group Inc., 1-4, Takanodai, Yotsukaido-shi, Chiba 284-0033, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Koyama
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuou-ku, Chiba-shi, Chiba 260-8675, Japan.
authors.forename: Kenjirou
authors.initials: K
authors.lastname: Higashi
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuou-ku, Chiba-shi, Chiba 260-8675, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuou-ku, Chiba-shi, Chiba 260-8675, Japan.
authors.forename: Kunikazu
authors.initials: K
authors.lastname: Moribe
mesh_terms: D002152:Calorimetry, Differential Scanning; D002788:Cholesterol Esters / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D008855:Microscopy, Electron, Scanning; D010840:Phytosterols / Q000378:metabolism*; D012995:Solubility; D014867:Water; D014961:X-Ray Diffraction; D047408:gamma-Cyclodextrins / Q000378:metabolism*
chemical_list: D002788:Cholesterol Esters; D010840:Phytosterols; D047408:gamma-Cyclodextrins; D014867:Water; C014409:cholesteryl oleate; C023792:gamma-cyclodextrin
keywords: Cholesteryl oleate; Cholesteryl oleate (PubChem CID: 5283632); Cryo-SEM; DSC; Gamma-cyclodextrin (PubChem CID: 86575); Inclusion complex; NMR; PXRD; Stoichiometry