Lactose chemical modifications

Fig. (10). Agar diffusion of different proteins and a lipid conjugated with lactose against anti-lactose antibodies (well L) and against anti-BSA antibodies (Well BS) wells 1-6 contained Lac-poly, Lac-BSA, Lac-sphingosine, Lac-ORA, Lac-HGG and BSA Chemical modification of the antigen by periodate oxidation or borohydride reduction can effect an agar diffusion against anti-gum arabic antibodies (Se), GA=gum arabic Bl=blank.

Thelwall LAW (1985) Developments in the chemistry and chemical modification of lactose. In Fox PE (ed) Developments in Dairy Chem-... 

In 1960, a patent was granted for the separation of D,L-prollne on a lactose column (56). Davankov s laboratory was the first to report separation of amino acid Isomers on polymeric resins derlvatlzed with optically active amino acids (57). However, separation of amino acid enantiomers by these techniques has been hampered by long separation times (ca. 10 hr) and the difficulty In synthesizing supports of sufficient quality for modern HPLC (spherical particles, small size, uniform chemical modification). Separation of amino acid Isomers on a column consisting of silica bonded with L-amlno acids and complexed with copper (II) has been reported by Gubltz and Jellenz (42). Short analysis times for separation of mixtures of single D,L-amlno acids were reported (ca. 30 min), but complex mixtures have not been separated. 

Nature already produces the desired structures, and isolation of these components mostly requires only physical methods without chemical modification. Examples comprise polysaccharides (cellulose, starch, alginate, pectin, agar, chitin, and inuUn), disaccharides (sucrose and lactose), and triglycerides, lecithin, natural rubber, gelatin, flavors and fragrances, etc. 

Brown, R. D. Matthews, K. S. Chemical modification of lactose repressor protein using N-substituted maleimides. J. Biol. Chem. 1979, 254, 5128-5134. 

Native starches are used as disintegrants, diluents, and wet binders. However, their poor flow and high lubricant sensitivity make them less favorable in direct compression. Different chemical, mechanical, and physical modifications of native starches have been used to improve both their direct compression and controlled-release properties (Sanghvi, 1993 van Aerde and Remon, 1988). Schinzinger and Schmidt (2005) used potato starch as an excipient and compared its granulating behavior with a-lactose-monohydrate and di-calcium phosphate anhydrous in a laboratory fluidized bed granulator using statistical methods. 

Figure 2 One-pot three-enzyme chemoenzymatic synthesis of sialosides containing sialic acid modifications. In this strategy, mannose or ManNAc derivatives are chemically or enzymatically synthesized. These compounds are then used by a recombinant coli K-12 sialic acid aldolase to obtain sialic acids and their derivatives followed by an N. meningitidis CMP-sialic acid synthetase for the formation of CMP-sialic acids. From which, sialic acids can be transferred to lactose, LacNAc, galactose, GalNAc, or their derivatives by a multifunctional P. muitocida sialyltransferase (PmSTl) or a P, damseia a2,6-sialyltransferase (Pd2,6ST) to form a2,3- or a2,6-linked sialosides in one pot without the isolation of intermediates.

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