2004 Fiscal Year Final Research Report Summary
Glycosylation of anthocyanins by glycosyltransferases
| Project/Area Number |
15580116
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Food science
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| Research Institution | MINAMI-KYUSHU UNIVERSITY |
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Principal Investigator |
TERAHARA Norihiko MINAMI-KYUSHU UNIVERSITY, FACULTY OF HEALTH AND NUTRITION, PROFESSOR, 健康栄養学部, 教授 (60155471)
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| Co-Investigator(Kenkyū-buntansha) |
HAYASHI Sachio MINAMI-KYUSHU UNIVERSITY, FACULTY OF ENGINEERING, PROFESSOR, 工学部, 教授 (90148916)
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| Project Period (FY) |
2003 – 2004
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| Keywords | Purple corn pigment / Anthocyanin pigment / Cyanidin 3-glucoside / Glycosyl transferase / Glycosidated C3G / Preparative ODS-HPLC system / CGTase / Optimum condition for glycosidation |
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| Research Abstract |
The semi-purified pigment and the pure cyanidin 3-glucoside (C3G) prepared in large quantities from purple corn pigment were examined the transglycosylation with various sugar substrates catalyzed by various sugar-related enzymes, resulting that cyclodextrin glucanotransferases (CGTases) best generated glycosylated C3G (Gly-C3Gs). Next, the transglycosylation of C3G was conducted with a commercial α-cyclodextrin powder Dexypearl K-100 as an optimum sugar substrate under a commercial CGTase Contizyme of as an optimum enzyme. It was ascertained that the optimum sugar concentration 100 g/100 mL, the optimum pH 4.0, the optimum pigment concentration 1g/100mL, and optimum reaction time 3 hours.
Under the optimum reaction condition, the large-scale glycosylation gave many highly glycosylated and hydrophilic Gly-C3Gs. Of them, six major Gly-C3Gs (G1-G6) could be isolated through various column separation and purification. HPLC, UV-Vis, and ESI/TOFMS analyses of the isolated G1-G6 resulted that they were presumed the non-natural type polyglycosides sequentially glycosidated glucose chain with α-1,4 bond on 4-OH of C3G-3-glucosyl residue.
Thus, we could obtain Gly-C3Gs expected by the large-scale reaction advanced in the same way as small-scale test, but each isolated glycoside was in very small amount. Therefore, conditional examination for yield up and evaluation for the stability and the functionality are future topics.
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