Περίληψη:
Natural attenuation can reduce contamination of tributyltin (TBT), but
persistence of the xenobiotic can cause long-term issues in the
environment. Biostimulation is used to accelerate biodegradation. This
study investigated the ability of individual organic nutrients and
growth factors to enhance TBT biodegradation by sediment microorganisms
(SED) and Enterobacter cloacae strain TISTR1971 (B3). The supplements
that produced high biomass yield were selected for degradation
enhancement. For TBT degradation at initial concentration of 0.1 mg/l,
negative or limited degradation was observed in some selected
supplements indicating that increasing the biomass did not necessarily
promote degradation. Consequently, the addition of nutrients was
expected to increase both dioxygenase activity and the degrader
population. At different concentrations of supplements, a mixture of
succinate/glycerol showed the highest removal for SED which reduced TBT
by 77%, 75%, and 68% for 0.1x, 1x, and 10x supplement concentration,
respectively. For B3, the addition of succinate showed degradation of
49% (0.1x), 75% (1x), and 77% (10x). Most nutrients and amino acids
had an inhibitory effect at 1x or 10x levels. Excess amount of the
nutrients added can inhibit the initial degradation of TBT. Therefore,
TBT biostimulation requires supplements that increase the capability of
TBT degraders at an appropriate amount.
Συγγραφείς:
Sakultantimetha, Arthit
Keenan, Helen E.
Beattie, Tara K. and
Bangkedphol, Sornnarin
Cavoura, Olga
