The experiment was carried out to investigate the effects of different
PAM concentrations on PAM degradation. HWBI and HWBII
were cultivated in liquid cultures of the MSMP containing different
concentrations of PAM of up to 1000mgL−1. The results are shown
in Fig. 3. The degradation of PAM by both of the isolates decreased
with the increasing PAM concentration in the cultures. For HWBI,
the maximum PAM removal efficiency of 70% was achieved in 96 h
cultivation with an initial PAM concentration equal to 50mgL−1.
However this dropped to 14% when the initial PAM concentration
increased to 1000mgL−1. For HWBII, a dramatic decrease in
the PAM removal efficiency was observed when the initial PAM
in the culture increased from 50 to 200mgL−1, where it showed