A method for preparing condiments containing 5'-nucleotides from yeasts

摘要

1,144,793. Nucleotide-containing condiments from yeast. TAKEDA CHEMICAL INDUSTRIES Ltd. 15 March, 1966 [15 March, 1965], No. 11378/66. Heading C2C. [Also in Division A2] Condiments containing 51-nucleotides are prepared from yeast by treatment, firstly with an enzymic system (A) produced by incubating micro-organisms of the genus Trametes and capable of hydrolysing nucleic acid into 51- nucleotides in an aqueous medium at a pH of about 8-11, and subsequently with another enzymic system (B) produced from the same genus and capable of solubilizing organic materials in an aqueous medium at a pH of about 2À5-7. Any kind of yeast, such as brewery, bakery, bottom, top or wine yeast, may be used. The micro-organisms are preferably incubated in a liquid medium on an industrial scale and may be cultured under shaken or stationary conditions, or with aeration. Submerged cultivation may also be used. The culture medium should contain carbon and nitrogen sources which are assimilable by the micro-organisms, e.g. starch, dextrin, ammonium salts and nitrates &c. as well as cornsteep liquor, peptones and meat extract. Mineral salts such as calcium, magnesium, potassium and zinc salts &c. may also be added. The micro-organisms are preferably incubated at a temperature of 15-35‹ C. at a pH of 3-6. The initial concentration of yeast is preferably 5-30% (wt./vol.) of the total reaction system. The liquid portion obtained from the enzymic treatments above is collected by centrifuging or filtration and contains 51-nucleotides including adenylic, guanylic, inosinic, cytidylic and uridylic acids. The liquid may be concentrated or dried to give a powder. If undesirable inorganic materials are present, they can be removed by using ion exchange resins. Enzymic system A is mainly accumulated in the solid portion of the culture broth and may be extracted by surface active agents, supersonic waves or other known means. Enzymic system B is usually contained in the culture filtrate and may be recovered, e.g. by precipitation or centrifuging.