33A-27 |
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K. S. CHO, S. H. Lee, H. J. Lee, T. W. Moon, and K.-H. Park. Department of Food Science and Technology, Seoul National University, School of Agricultural Biotechnology, San 56-1. Silim-dong, Kwanak-gu, Seoul, 151-742, South Korea The polyols are used as low-calorie bulking agents. They do not under go Maillard reaction and have reduced caramelization and low viscosity. In addition, the polyols generally are tooth-friendly, and suitable for diabetics. Transglycosylation reactions have been used to improve physicochemical or physiological properties of the existing sugars. Maltogenic amylase from Bacillus stearothermophilus (BSMA) catalyzes the transglycosylation reaction in the presence of suitable glycosyl acceptors. In this study, production of maltosyl-mannitol by a transglycosylation reaction, structural determination of the transferred product, and determination of some physicochemical properties and dental caries suppression effect were carried out. Maltosyl-mannitol was produced by the transglycosylation reaction of BSMA. Maltotriose and mannitol acted as a donor and an acceptor, respectively. The presence of the mannitol transfer products was confirmed by HPIC and TLC analyses. The transfer product was purified with Bio-Gel P-2 column chromatography and recycled preparative high pressure liquid chromatography. The structure was identified by LC-MS, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS), and 13C- and 1H-NMR. The transfer product was determined to be 6G-a-D-maltosyl-mannitol, in which the maltose unit was attatched to the mannitol by an a-(1,6)-glycosidic linkage. The molecular mass was estimated to be 506.2 and 529.8 daltons from the MALDI-TOF-MS analysis. The sorption isotherm of maltosyl-mannitol at 25°C was found to be a type III isotherm. Solubility of maltosyl-mannitol was 2.5 times higher than mannitol. Flow curve of 10, 20, and 30% solution of maltosyl-mannitol displayed Newtonian fluid characteristics, and viscosity of maltosyl-mannitol increased with increasing concentration. The inhibitory effect of maltosyl-mannitol on the synthesis of water-insoluble glucans by S. sobrinus was about 85 times higher than mannitol. Also maltosyl-mannitol did not support acid production for more than 12 h of incubation. These results showed that maltosyl-mannitol is a suitable sugar substitute for food products with non-cariogenicity.
Session 33A, Carbohydrate: General
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