Ota M, Tonosaki K, Miwa K, Fukuwatari T, Ariyoshi Y
Central Research Laboratories, Ajinomoto Co., Inc. Kawasaki, Japan.
Biopolymers. 1996 Aug;39(2):199-205. doi: 10.1002/(SICI)1097-0282(199608)39:2%3C199::AID-BIP8%3E3.0.CO;2-K.
The sweetness-suppressing polypeptide gurmarin isolated from the leaves of Gymnema sylvestre consists of 35 amino acid residues including three intramolecular disulfide bonds. Herein, the total chemical synthesis of gurmarin was performed by the stepwise fluoren-9-ylmethoxy-carbonyl solid-phase method, the yield of reduced gurmarin being 1.9% based on the starting amino acid resin. Disulfide formation was carried out in the presence of a redox system of reduced glutathione/oxidized glutathione to give gurmarin in a yield of 35.5%. The product was identical to natural gurmarin by analytical reverse phase high performance liquid chromatography (RP-HPLC), mass spectroscopy (MS), and peptide mapping, and suppressed the responses to sucrose, D-glucose, and L-glucose in a rat. The D enantiomer (all D-amino acid gurmarin) was also synthesized, and was shown to be the mirror image of gurmarin. Interestingly, the D enantiomer (ent-gurmarin) also suppressed the responses to sucrose, D-glucose, and L-glucose in a rat.
从匙羹藤叶中分离出的甜味抑制多肽奇果菌素由35个氨基酸残基组成，包括三个分子内二硫键。在此，通过逐步芴-9-基甲氧基羰基固相法进行了奇果菌素的全化学合成，基于起始氨基酸树脂，还原型奇果菌素的产率为1.9%。在还原型谷胱甘肽/氧化型谷胱甘肽的氧化还原体系存在下进行二硫键形成，得到奇果菌素的产率为35.5%。通过分析型反相高效液相色谱（RP-HPLC）、质谱（MS）和肽图谱分析，该产物与天然奇果菌素相同，并抑制了大鼠对蔗糖、D-葡萄糖和L-葡萄糖的反应。还合成了D对映体（全D-氨基酸奇果菌素），并证明其为奇果菌素的镜像。有趣的是，D对映体（对映体奇果菌素）也抑制了大鼠对蔗糖、D-葡萄糖和L-葡萄糖的反应。
