Table 1.

Saturation and detection limits of the different biosensors with toluene, benzene, p‐xylene and m‐xylene

	LD	Induction fold	LS	Induction fold	Basal fluorescence
Alcanivorax borkumensis SK2 (pKST‐1)
Toluene	0.04	2 ± 0.31	40	17.01 ± 1.58	90 236 ± 4711
Benzene	0.15	2 ± 0.12	0.5	8.91 ± 0.62
p‐Xylene	1.5	2 ± 0.35	80	16.87 ± 0.27
m‐Xylene	70	2 ± 0.43	125	14.15 ± 0.41
Pseudomonas putida KT2440 (pKST‐1)
Toluene	0.9	2 ± 0.09	250	35.20 ± 1.8	46 837 ± 7616
Benzene	0.4	2 ± 0.22	100	23.45 ± 1.20
p‐Xylene	25	2 ± 0.04	110	11.50 ± 0.23
m‐Xylene	45	2 ± 0.28	125	9.74 ± 0.48
P. putida DOT‐T1E (pKST‐1)
Toluene	0.9	2 ± 0.59	460	91.44 ± 10.12	69 022 ± 2769
Benzene	0.2	2 ± 0.14	150	53.55 ± 1.07
p‐Xylene	5	2 ± 0.47	125	39.47 ± 0.78
m‐Xylene	40	2 ± 0.12	125	17.31 ± 1.03

Concentration data are given in mg l⁻¹.

LD: detection limit, concentration when induction ratio is 2. LS: saturation limit, concentration when induction ratio is maximum. Induction fold: relative to the fluorescence of the control without inducer.