Production of water-soluble chitin-oligomers by partial hydrolysis of
申请人:Ihara Chemical Industry Co., Ltd.
公开号:US04804750A1
公开(公告)日:1989-02-14
Tetra-N-acetyl-chitotetraose, penta-N-acetylchitopentaose and hexa-N-acetyl-chitohexaose, ones of the water-soluble chitin-oligomers, may be obtained in improved yields, when finely ground chitin is quickly and intimately mixed with a concentrated hydrohalogenic acid containing a particular proportion of the hydrogen halide per a unit quantity of the chitin under the irradiation with ultrasonic waves and also under the agitation by mechanical stirrer, followed by hydrolyzing the chitin in the resulting homogeneous mixture comprising the chitin and the concentrated hydrohalogenic acid while said homogeneous mixture is further continuously irradiated with the ultrasonic waves and also agitated by the mechanical stirrer. From the aqueous phase of the hydrolyzed reaction mixture are recovered the desired water-soluble chitin-oligomers which are each useful as an immunopotentiating, antitumor agent or antifungal, antibacterial agent.
申请人:Director of National Food Research Institute, Ministry of Agriculture,
公开号:US05955320A1
公开(公告)日:1999-09-21
Di-N-acetyl-D-chitobiose, which is easily available as a chitin decomposate or a chemical reagent, is reacted with a microorganisms-derived deacetylase to produce 2-acetylamino-4-O-(2-amino-2-deoxy-.beta.-D-glucopyranosyl)-2-deoxy-D-gluc ose of formula (1). ##STR1## The method is quantitative and efficiently produces the compound (1). The compound (1) and its salts are usable as substrates for measuring enzymatic activities, and also as starting substances in the production of various food materials and in the field of glyco-chain engineering.
Antibodies having modified carbohydrate content and methods of preparation and use
申请人:THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK
公开号:EP0359096A1
公开(公告)日:1990-03-21
This invention provides a method of altering the affinity of an antibody for the antigen to which it is directed which comprises introducing into the variable region of the antibody a carbohydrate recognition site under conditions such that a carbohydrate binds to the site and thus attaches to the antibody. This invention also provides a method of modifying the carbohydrate content of an antibody which comprises deleting from a constant region of the antibody a carbohydrate recognition site which naturally occurs in such constant region of such antibody. Antibodies, e.g., monoclonal antibodies and human monoclonal antibodies, diagnostic test kits, DNA encoding antibodies, therapeutic agents, and methods for detecting the presence of a substance in a sample, and for recovering and purifying a substance from a sample are also provided.
Methods for removing microorganisms, such as bacteria, from surfaces by treatment with Type II endoglycosidase alone or in combination with other enzymes and/or detergents.