Figure 5: Co-metabolic degradation of PAHs in binary substrate systems. Degradation of acenapthene (0.5 g/l) (a), benzo[a]pyrene (0.1 g/l) (b), benz[a] anthracene (0.5 g/l) (c), fluoranthene (0.5 g/l) (d), pyrene (0.5 g/l) (e) by Sphingobium sp. strain PNB, along with phenanthrene (0.5 g/l) as cosubstrate. Symbols: (●), phenanthrene abiotic control; (○) substrate abiotic control; (■) phenanthrene degradation; (□) substrate degradation. Panel (f) shows growth profiles of strain PNB during co-metabolism in binary substrate systems and phenanthrene alone. Phn, Pyr, Flu, BzA, Acn and BaP represents phenanthrene, pyrene, fluoranthene, benz[a]anthracene, acenapthene and benzo[a]pyrene, respectively. Vertical bars represent mean ± SDs from triplicate measurements.