Figure 1.
Growth curves of Bacillus subtilis RKJ 700 in different conditions.
Growth of Bacillus subtilis RKJ 700 in (a) 10 mM glucose (as positive control), (b) 0.5 mM 4C2NP (negative control), (c) ) 10 mM glucose and 0.5 mM 4C2NP, (d) ) 10 mM glucose and 1 mM 4C2NP, (e) 10 mM glucose and 1.5 mM 4C2NP, and (f) 10 mM glucose and 2.0 mM 4C2NP.
Figure 2.
Decolourization of 4C2NP by Bacillus subtilis RKJ 700 at various concentrations.
Decolourization of the minimal media containing 10 mM glucose and (a) 0.5 mM 4C2NP, (b) 1.0 mM 4C2NP, (c) 1.5 mM 4C2NP, and (d) 2.0 mM 4C2NP.
Figure 3.
HPLC analysis of the samples collected from different intervals.
HPLC elution profiles of the sample collected from (a) 0 h, (b) 8 h, (c) 16 h and (d) 24 h.
Figure 4.
Degradation curve of 4C2NP based on HPLC data.
Quantification of amounts of 4C2NP and its metabolites in sample collected from different intervals (0, 8, 16, 24 and 28 h).
Figure 5.
Mass fragments of metabolites and authentic standards.
Mass fragments of the authentic 4C2AP (a), metabolite I (b), authentic 4C2AAP (c), metabolite II (d), authentic 5C2MBZ (e) and metabolite III (f).
Figure 6.
Resting cell studies showing stoichiometric formation of 5C2MBZ from 4C2NP.
The resting cells of Bacillus subtilis RKJ 700 completely depleted 4C2NP with stoichiometric formation of 5C2MBZ within 40 minutes.
Figure 7.
Proposed pathway of degradation 4C2NP for Bacillus subtilis RKJ 700.
4C2NP initially reduced to 4C2AP, which undergo acetylation to form 4C2AAP. After cyclization, 4C2AAP forms 5C2MBZ.