A preliminary study on photoproduction of hydrogen by Rhodobacter capsulatus KU002 isolated from leather industry effluents under different cultural conditions with various carbon and nitrogen sources was investigated. Hydrogen production was measured using a Gas chromatograph. Lactate promoted more amounts of hydrogen production under anaerobic light conditions and aerobic light conditions. Cumulative hydrogen production by the organism was recorded at various time intervals. Incubation period of 120 h was optimum for production of hydrogen. pH 7.0 +/- 0.2 was optimum for production of hydrogen by growing cells, while pH 7.5 +/- 0.26 for resting cells. L-cystine was a good nitrogen source for production of hydrogen. Growing cells produced more amount of hydrogen than resting cells. Glutamine was a poor nitrogen source for hydrogen production by Rb. capsulatus. Significance of the above results in the presence of existing literature is discussed. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.