• Journal of Mushroom
• /
• v.10 no.4
• /
• pp.216-223
• /
• 2012

Oyster mushroom is one of the popular mushrooms for Korean people and it is thus one of the mushrooms that were mostly cultivated in Korea in addition to winter and king oyster mushrooms. To promote the consumption in terms of its nutritional value and determine the absorption mechanism in its physiological and metabolic aspects, we investigated the sugar composition of its fruit bodies according to the amount of sugar component in the medium. As a result from the treatment of 4 different sugar components to the sawdust medium of oyster mushroom varieties (i.g., Suhan 1 ho, Yeorum, Chunchu 2 ho), we detected fructose, glucose, ribose, xylose as a monosaccharide with ${\alpha}$-lactose and trehalose as a disaccharide. The sugar alcohols were also detected including glycerol, mannitol, myo-inositol, and sorbitol. The sugar components that were detected in all treatments were trehalose, mannitol, ${\alpha}$-lactose, fructose, glucose, ribose, and myo-inositol and the rest of the components were found in some treatments with their different quantity included in the fruit bodies. The amount of monosaccharides included in fruit bodies is comparatively low and Suhan 1 ho contained them more than other varieties. There was no remarkable difference in the amount of sugar components in fruit bodies depending on treated sugars and their amounts in the treatment. With the increase of lactose treatment, the sugar components were markedly increased and the amount of trehalose in the fruit bodies was different according to the varieties. Therefore, it is not possible to detect the trend of sugar components according to the medium used in the cultivation. The sugar alcohols in the fruit bodies were comparatively contained more in Suhan 1 ho and Chunchu 1 ho. The amount of mannitol in the fruit bodies was not possible to be detected in terms of its trend according to the treatment. For myo-inositol, its quantity is gradually increasing in Suhan 1 ho and Chunchu 1 ho and it is not possible to detent the trend in Yeorum. In conclusion, we only detected ${\alpha}$-lactose as a sugar component that showed a correlation between the amount of treatment and the amount of the fruit bodies. Therefore, the sugar components detected in the fruit bodies were transformed rather than direct absorption into fruit bodies and further studies are needed to address this question.

• The Korean Journal of Mycology
• /
• v.40 no.4
• /
• pp.229-234
• /
• 2012

A key molecule in the pathogenesis of Alzheimer's disease (AD) is the ${\beta}$-amyloid peptide ($A{\beta}$) generated by ${\beta}$-secretase activity, an aspartic protease. This study was designed to evaluate inhibitory effect of the high-molecular weight water-soluble polysaccharides (Et-P) isolated and purified from Phellinus linteus fruiting body on ${\beta}$-secretase activity. The Et-P was purified from the hot water extract of Phellinus linteus fruiting body mainly by 75% ethanol precipitation and DEAE-Cellulose column chromatography. From the DEAE-Cellulose chromato-gram and molecular weight analysis, the Et-P was shown to be a mixture of three polysaccharides with molecular mass of 1,629, 1,294, and 21 kDa, respectively. The monosaccharide composition of Et-P was determined to be glu-cose, galactose, and mannose as major sugars, glucose being the most prominent one (48% in mole percentage). The elemental analysis and FT-IR analysis suggested that Et-P is typical polysaccharides having at least partially ${\beta}$-linkages and possible existing as complex with phenolic compounds. The laminarinase digestion and HPAEC-PAD analysis suggested that Et-P is a variant of beta-(1,3)-glucans. The Et-P showed DPPH radical scavenging activity and, especially, a significant inhibitory activity on ${\beta}$-secreatase activity (48% inhibitin at 100 ${\mu}g/mL$), suggesting that they may inhibit the formation of $A{\beta}$ which is the major causative of Alzheimer's disease. The results of this study suggest that the water soluble polysaccharides of Phellinus linteus fruiting body can be a potent material for the development of preventive or therapeutic agents for AD.