Structure of a novel α-glucan substitute with the rare 6-deoxy-d-altrose from Lactarius lividatus (mushroom)

• Published in: Carbohydrate polymers 2013-02, Vol.92 (2), p.2135-2140
• Main Authors: Tako, Masakuni, Dobashi, Yahiko, Shimabukuro, Junpei, Yogi, Takuya, Uechi, Keiko, Tamaki, Yukihiro, Konishi, Teruko
• Format: Article
• Language: English
• Subjects: 6-Deoxy-d-altrose; Agaricales - chemistry; Applied sciences; Biological and medical sciences; carbon; Chemical structure; Deoxy Sugars - chemistry; Deoxy Sugars - isolation & purification; Exact sciences and technology; fruiting bodies; Fundamental and applied biological sciences. Psychology; galactose; Glucans - chemistry; glucose; Hexoses - chemistry; Hexoses - isolation & purification; Lactarius; Lactarius lividatus; Methylation; Microbiology; Morphology, structure, chemical composition; mushroom bodies; mushrooms; Mycology; Natural polymers; Novel α-glucan; nuclear magnetic resonance spectroscopy; Physicochemistry of polymers; polysaccharides; stable isotopes; Starch and polysaccharides
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2012.11.010

► The polysaccharide isolated from Lactarius lividatus was highly branched α-d-glucan. ► The terminal residues were 6-deoxy-β-d-altropyranose and α-d-galactopyranose. ► This work is the first demonstration of the rare 6-deoxy-d-altropyranose moiety on polysaccharides. A novel α-glucan substituted rare 6-deoxy-d-altropyranose was isolated from edible fruiting bodies of a mushroom (Lactarius lividatus) grown in Okinawa, Japan. The polysaccharide consists of d-glucose, d-galactose and 6-deoxy-d-altrose in a molar ratio of 3.0:1.0:1.0. The specific rotation [α]589 was estimated as +64.3° (0.2% in water) at 25°C. Based on results of IR, NMR (1H, 13C, 2D-COSY, 2D-HMQC, 2D-ROESY and 2D-HMBC), and methylation analyses, the structure of the polysaccharide was determined as ▪ This work is the first demonstration of rare 6-deoxy-d-altropyranose moiety on polysaccharides.