title: Digestibility and chemical species of selenium contained in high-selenium yeast.
abstract: To evaluate the bioavailability of selenium (Se) in high-Se yeast (SeY), the digestibility and chemical species of Se in SeY were investigated. Both Se and nitrogen in SeY were readily released into the soluble fraction through trypsin digestion. In a Sephadex G-25 gel chromatography of the trypsin digest of SeY, the range in which Se was eluted was coincident with the range in which peptide fragments were eluted. Se was distributed almost uniformly within the range and there was no fraction that contained Se in a specifically high amount. A proteolytic enzyme extract of SeY was found to contain Se as selenomethionine (74.8%), selenocystine (9.9%), selenite (5.1%) and as at least three unknown Se compounds (10.2%) when analyzed using high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). These results indicate that Se in SeY is mainly present as selenomethionine non-specifically incorporated into peptide chains and is highly digestible. Accordingly, it is concluded that the bioavailability of Se in SeY is high.
authors.affiliation: Laboratory of Food and Nutritional Sciences, Department of Biotechnology, Faculty of Engineering, Kansai University, Suita, Osaka 564-8680, Japan. hanmyou4@ipcku.kansai-u.ac.jp
authors.forename: Munehiro
authors.initials: M
authors.lastname: Yoshida
authors.forename: Satoru
authors.initials: S
authors.lastname: Sugihara
authors.forename: Toru
authors.initials: T
authors.lastname: Suenaga
authors.forename: Chitose
authors.initials: C
authors.lastname: Naito
authors.forename: Kenji
authors.initials: K
authors.lastname: Fukunaga
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsuchita
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004063:Digestion / Q000502:physiology; D066298:In Vitro Techniques; D013058:Mass Spectrometry; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D012643:Selenium / Q000737:chemistry* / Q000378:metabolism*; D014357:Trypsin / Q000494:pharmacology
chemical_list: D014357:Trypsin; D012643:Selenium