The screening for PAM-degrading microorganisms was carried
out at 37 ◦C on a shaking platform at 150rpm by the enrichment
culture technique [12]. 10 g of soil sample or activated sludge sample
was mixed with 150mL MSMPY or MSMP in a 250mL conical
flask. After aerobic cultivation at 37 ◦C for several days, the systems
in which PAM was degraded were chosen for further cultivation.
0.1mL of this culture was streaked on agar plates containing either
MSMPY or MSMP. The plates were then incubated for 3 days at
37 ◦C. More than 100 well-separated colonies from each of the two
mediums were randomly isolated. These isolates were routinely
spread onto LB plates (NaCl 10 g, yeast 5 g, peptone 10 g, sterile
distilled water 1000 mL) to test the purity. The degrading ability
of the pure isolates was assessed in test tubes (25 mL) containing
10mL of MSMYP or MSMP. The test tubes were incubated on a
shaking platform at 150rpm for 1–5 days at 30 ◦C. Those which
showed PAM degradation were finally streaked onto fresh MSMP
agar plates and LB plates to ensure purity. Strains that showed a
good performance for the degradation of PAM were chosen for further
study. The procedures were repeated for the isolation of the
microorganism.