Comparative Study of PAH Degradation Using Bacteria Grown on Agar and Gellan Gum Media

A mean high concentration of high molecular weight (HMW) polycyclic aromatic hydrocarbons (PAHs) compounds was detected in sediment collected from Tanoura Bay on the Yatsushiro Sea in Japan with concentration 30,200 ng/g (dry weight). The indigenous bacteria applied were Burkholderia fungorum isolate no 1 and Mycobacterium gilvum isolate no 13. A culture preparation approach was carried out using the bacteria grown on two media. B. fungorum isolate no 1 grown on the agar (Bf-A) and the strain grown on the gellan gum (Bf-G) can degrade fluoranthene and pyrene at the level of 56.1 % + 8.1; 62.4 % + 7.7 at 20-day and 96.2 + 0.5; 96.3 + 0.2 at 16-day incubation of a period, respectively. Furthermore, fluoranthene and pyrene could be reduced by M. gilvum isolate no 13 grown on the agar media (Mg-A) and those grown on the gellan gum (Mg-G) at the concentration of 70.9 + 6.2; 78.6 + 0.4 after 24 days and 86.4; 98.5 + 2.5 after 12 days. Almost the entire fluoranthene and pyrene degradation required 24 - 28 days and 16 - 20-day incubation of a period, respectively. Compared with bacteria grown on agar, bacteria grown on gellan gum had an easier PAHs degradation process than other.