The performance of pyridine degradation by Paracoccus sp. strain KT-5 immobilized on bamboo-based activated carbon was investigated and compared with that of free cells. The results showed that Paracoccus sp. was able to attach well on the surface and pores of bamboo-carbon. Compared with freely suspended cells, the pyridine-degrading rate of the immobilized cells was higher when initial pyridine concentration was in the range of 489-1476 mg/L, suggesting that the efficiency of pyridine degradation by Paracoccus sp. strain KT-5 was enhanced significantly by immobilization technique. Additionally, the attached biomass on the bamboo-carbon increased from 391.9 to 430-500 mg/g during pyridine degradation. Furthermore, the semi-continuous degradation of pyridine by immobilized cells were carried out when the pyridine concentration was in the range of 293-1476 mg/L, the results demonstrated the feasibility and reusability of immobilized cells for pyridine degradation. (C) 2010 Elsevier Ltd. All rights reserved.