Large Scale Processing of Tetanus Toxin from Fermentation Broth

773-778Separation of bacterial cells, concentration and sterile filtration are some of the major unit operations in the processing of large volumes of fermentation broth in the production of bacterial vaccines. Separation of cells is traditionally achieved by centrifugation or by dead-ended depth filtration. These solid-liquid separation methods are time consuming, toxin recoveries are not satisfactory and it is difficult to validate a depth filtration system. Tetanus toxoid is prepared by detoxifying the culture filtrates of Clostridium tetani and further purifying it by ultrafiltration and salt fractionation. This article describes comparison of performance of deadend filtration and Tangential Flow Filtration (TFF) system for clarification of tetanus fermentation broth and further use of a similar system for concentration and purification of tetanus toxoid