Lee B Eppstein

US Patent:

46802673, Jul 14, 1987

Filed:

Mar 1, 1985

Appl. No.:

6/707363

Inventors:

Lee B. Eppstein - New Brunswick NJ
Robert D. Mohler - Bridgewater NJ
Shaul Reuveny - Highland Park NJ

Assignee:

New Brunswick Scientific Company, Inc. - Edison NJ

International Classification:

C12M 136

US Classification:

435289

Abstract:

A method and an apparatus for controlling the concentration of oxygen and pH of a medium during a bioreaction process in a vessel. The method and apparatus are particularly adapted to a fermentation process. A dissolved oxygen sensor generates a signal corresponding to the pH of the medium and a dissolved oxygen sensor generates a signal corresponding to the dissolved oxygen in the medium. A valve mechanism selectively applies air, N. sub. 2, O. sub. 2 and CO. sub. 2 to the medium. A controller produces a control signal for controlling the operation of the valve means so that a substantially fixed volume of gas consisting of one or more of air, CO. sub. 2, N. sub. 2 and O. sub. 2 are added to the fermenting medium during a period of time. The controller determines in response to the dissolved oxygen and pH signals, the amount of CO. sub. 2, O. sub. 2 and/or N. sub.