ISOLATION, CHARACTERISATION AND DEGRADATION OF DDT, DDD, AND DDE BY FILAMENTOUS FUNGI

Abstract

Biotteatment  of POPs  is an effect  method, which can mineralize harzadous pollutants without  producing toxical  secondary  metabolites.  Treatment  of pollutants  including  DDT, DDD, DDE,  HCH  etc. at pilot  scale was carried out in bioreactor containing  100 kg contaminated  soil. Five filamentous fungal  and two bacterial sfrains were isolated from treated soil samples collected after  7 days of biofreatment.  Sequence of a 18S rRNA gene  fragment  of  FNA4  was  determined.  Partial  sequence  of  18S  rRNA  gene  of  FNA4  has  99  -  100%homology to those of other representatives of Aspergillus genus. Based on orphological characteristics and as partial sequence of its  18S rRNA gene, FNA4 sfrain  was classified  and named as Aspergillus sp. FNA4. After 14 days  cultivation,  FNA4  degraded  94.48% mbitare  of DDT, DDD,  and  DDE with  initial  concenfration  of 52.57 ppm.  Sfrain  FNA4 produced  exfracellular  enzjmie  laccase with  activity  15.38 U/l. Four  other  isolated fungal  sfrains  produced  laccase  and  lignin  peroxidase  or  manganese  peroxidase   Laccase  activities  of  four sfrains FNAl, FNA2, FNA3, and FNA5 were 30.9; 33.8; 9.2; 12.3 U/l respectively. FNAl  and FNA2 produced lignin peroxidase with  activities were  187.1 and  34.6 U/l. FNA3 and FNA5 produced manganese  peroxidase with activities were 1,076; 470.8 U/l.