Biodegradation of 2-chloro-4-nitrophenol via a hydroxyquinol pathway by a Gram-negative bacterium, Cupriavidus sp. strain CNP-8

AMB Express

Table 1 Effect of temperature, pH, and glucose addition on 2C4NP degradation by strain CNP-8

Abiotic factors		OD ^d₆₀₀	Time required for complete decolorization of 2C4NP (h)	Degradation rate (μM/h)^e
Temperature (°C)^a	20	0.105 ± 0.007	57 ± 3.1	5.3
	25	0.114 ± 0.008	28 ± 1.9	10.7
	30	0.137 ± 0.009	21 ± 2.2	14.3
	35	0.092 ± 0.006	31 ± 2.6	9.7
	40	0.073 ± 0.012	62 ± 4.5	4.8
pH^b	4	ND	ND	ND
	5	0.112 ± 0.016	32 ± 2.6	9.4
	6	0.127 ± 0.014	22 ± 1.4	13.6
	7	0.135 ± 0.008	20 ± 2.5	15.0
	8	0.124 ± 0.011	23 ± 1.8	13.0
	9	0.103 ± 0.009	38 ± 2.7	7.9
	10	0.095 ± 0.014	54 ± 3.8	5.6
Glucose addition (g/L)^c	–	0.133 ± 0.010	21 ± 1.8	14.3
	0.2	0.227 ± 0.014	12 ± 2.4	25.0
	0.5	0.342 ± 0.024	16 ± 1.6	18.8
	5	1.476 ± 0.038	49 ± 5.4	6.1

MSM containing 0.3 mM of 2C4NP was inoculated by strain CNP-8 with initial OD₆₀₀ about 0.05 and shaken at 180 rpm
^apH of MSM was 7
^bCulture temperature was 30 °C
^cpH of MSM was 7 and culture temperature was 30 °C
^dOD₆₀₀ was determined at the time of complete decolorization of 2C4NP
^eRate of 2C4NP degradation (μM/h⁻¹) = 300/time required for complete decolorization of 2C4NP