Benzene was purchased from Echo Chemical (Germany),
toluene was obtained from Fisher Chemical (USA), and both
ethylbenzene and p-xylene were obtained from Tedia Company
(USA). The BTEX compounds were of HPLC purity, the
remaining compounds were of analytical purity. The two competent
degrading strains used to bioremediate the contaminated
groundwater, Mycobacterium sp. CHXY119 and Pseudomonas
sp. YATO411, worked in the form of immobilized beads.