OPTIMIZATION OF GROWTH CONDITIONS FOR CRUDE OIL AND N-HEXADECANE DEGRADING PSEUDOMONAS SPP. FROMINDUSTRIAL AREAS

摘要

In the present study the optimization of growth conditions for crude oil and n-Hexadecane degrading Pseudomonas spp. were done using Bushnell Haas (BH) Medium. Out of the 32 isolates from the industrial areas of Kerala, Tamil Nadu, Mumbai and Karnataka, Pseudomonas spp. from Ambalamugal (PI) near oil refinery, Kerala was found to be the most efficient crude oil and n-Hexadecane degrader. The growth pattern of the (PI) isolate was evaluated in BH broth supplemented with crude oil and n-Hexadecane (lmL/lOOmL) individually at different pH (4, 5, 6, 7, 8 and 9), temperature (20, 37, 50 and 60°C) and varying salt concentrations of magnesium sulphate (0.05, 0.10, 0.15, 0.20, 0.25g/L), ferric chloride (0.02, 0.04, 0.06, 0.08, O.lOg/L) and calcium chloride(0.005, 0.01,0.015, 0.02, 0.025g/L). The incubation period was for ten days in shaker (120rpm). Optical density at 600nm was recorded on 3, 5, 6, 8 and 10th day. The optimum BH medium composition obtained by experiments for the degradation of crude oiland n-Hexadecane degradation showed maximum growth at pH 7 and 37°C with a salt concentration of magnesium sulphate 0.25 g/L, calcium chloride 0.02 g/L and ferric chloride 0.04 g/L. The bacteria were found to be degrading up to 20% of crude oil and 20%of n-Hexadecane under optimized conditions on 10th day.