Lactose with lactitol

Electrolytic reduction of a lactose solution containing inorganic sulfite, between an amalgamated lead cathode and a graphite anode, is reported to give a 90% yield of lactitol with a 90% current-efficiency. ... 

Lactitol and lactose monoesters esters have been prepared by Drummond and Wells [25] with the add ehloride fatty acid derivatives of Cg ig... 

Figure 12.3. Lactose hydrogenation at 120°C and 50 bar on Ru/C (main product lactitol, by-product with maximum lactulose). Fit of model (1-3, 4b).

Hydrogenation of lactose to lactitol on sponge itickel and mtheitium catalysts was studied experimentally in a laboratory-scale slurry reactor to reveal the true reaction paths. Parameter estimation was carried out with rival and the final results suggest that sorbitol and galactitol are primarily formed from lactitol. The conversion of the reactant (lactose), as well as the yields of the main (lactitol) and by-products were described very well by the kinetic model developed. The model includes the effects of concentrations, hydrogen pressure and temperature on reaction rates and product distribution. The model can be used for optinuzation of the process conditions to obtain highest possible yields of lactitol and suppressing the amounts of by-products. 

Lactitol is a disaccharide sugar alcohol prepared by reduction of the glucose residue to a sorbitol group. It is prepared by hydrogenation of a lactose solution hydrogenation at 100°C for 6 hr and 8825 kPa with a Raney nickel catalyst produces lactitol in nearly quantitative yield (van Velthuijsen 1979 Linko et al. 1980). Hydrogenation of lactose with sodium or calcium amalgam catalysts and reduction with sodium borohydride (Scholnick et al 1975) have also been successful. 

The lactose esters and their ethyoxylated (prepared by treatment with ethylene oxide) derivatives possessed surfactant properties comparable to those shown by analogous sucrose derivatives. The best detergency properties were shown by the lower fatty acid monoesters of lactose. The comparable lactitol esters were slightly better detergents than the lactose esters no improvement was brought about in either case by the ethylene oxide adducts. The esters of both lactose and lactitol are readily biodegradable. 

D-Lactitol (4-0-(p- galactosyl)-D-glucitol) is an interesting and expensive (10 g 300) glycoside made of a cyclic galactopyranose and an open-chain glu-citol. It is obtained by reduction of lactose with sodium borohydride or, technically, by catalytic hydrogenation. It is useful as sweetener for diabetics and does not induce dental caries. 

NeuSAc is a weak inhibitor of classical sialidases but does not act at all on the trans-sialidases. Correspondingly, the 2,3-difluoro derivative of NeuSAc, forming a covalent intermediate with sialidases and trans-sialidases (see later) was required at high concentrations (20 mM) to inactivate the enzyme completely Since trans-sialidases possess a lactose-binding site in their active center (as described next), lactose and its derivatives, especially lactitol, inhibit the sialic acid transfer of the enzyme from T. cruzi. Oligosaccharides from the mucins of this trypanosome can also inhibit the transfer of sialic acid to, for example, the substrate A-acetyllactosa-mine. It should be noted that heavy metal ions, especially merciuy, are potent inhibitors of sialidases and trans-sialidases. The latter enzymes do not require calcium ions, in contrast to some siaUdases. " " " ... 

Lactitol has been prepared by catalytic or borohydride reduction of lactose, and their properties have been compared lactitol was found to be much less readily consumed by microorganisms, probably reflecting a lower 3-galacto-sidase efficiency with this substrate. ... 

Additional disaccharidic esters such as lactose and lactitol esters with varying alkyl chain lengths were reported in the literature (Fig. 7.10) [19]. These derivatives behave similarly to sucrose esters with the same hydrocarbon chain length, although they have a tendency towards closer packing at the air-water interface for the open chain type. 

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