Degradation of caffeine by Pseudomonas alcaligenes CFR 1708

Due to the known adverse effects of caffeine in the widely consumed beverages like coffee and tea, a caffeine free product is desirable. The commonly used solvents in decaffeination suffer from the disadvantage of being carcinogenic or increase the process costs tremendously. A biotechnological approach for decaffeination involving microbial cells or enzymes is viewed as a potential alternative approach. Present studies on the degradation of caffeine were carried out using a strain of Pseudomonas alcaligenes CFR 1708, isolated from coffee plantation soil. The enzymes responsible for caffeine degradation were found to be inducible. Pre-induction of the microbial cells in a medium containing caffeine as the sole source of carbon and nitrogen was carried out for 48 h. The induced bacterial cells were found to be capable of completely degrading caffeine (1 g/l) from solutions containing caffeine, within 4 to 6 h at 30 +/- 2 degrees C in the pH range of 7.0-8.0. To make the process of decaffeination application oriented immobilisation of cell debris were done and used in designed bioreactor for continuous decaffeination process. (c) 2005 Elsevier Inc. All rights reserved.