An improved method for the preparation of 3-ketoglycosides

Summary Improved conditions were described to increase the yield of 3-ketoglycosides, which are formed during the oxidation of several disaccharides and bionates by a strain of aerobic bacteria. These end-products were formed fastest when a heavy inoculum (10¹⁴–10¹⁵ cells/ml) of non-adapted organisms was used. The aeration rate was found to be very important. An oxygen absorption rate (O.A.R.) of 6 was currently used. In these conditions a 4% solution of lactose, lacto- and maltobionate was nearly quantitatively converted into the corresponding 3-keto-compounds. Maltose and saccharose gave a yield of 12 and 20% respectively. An analytical method to determine 3-ketoglycosides with semicarbazide was described. 3-Ketolactose has been obtained in the crystalline state. Geassocieerde Nationaal Fonds voor Wetenschappelijk Onderzoek.