수은, 6가크롬 오염토양으로부터 분리된 방선균군의 생태학적 특성

Abstract

- Ecological characteristics of microbial populations inhabiting heavy metal pollutedsoil were investigated. The samples were collected from 293 sites around an factory and industry-do. We measured the contents of seven heavy metal elements (Cd, Cu, As,Hg, Pb, Cr6+ , CN), seven sites have been seriously contaminated by mercury and chrome. Aquantitative evaluation of microbial populations in mercury and chrome contaminated soil wasexamined by using plate count method. Bacterial numbers in polluted soil samples ranged from7.4× 105 to 9.3× 107 cfu g-1, about 10~ 100 fold less than the count for the unpolluted soil.Moulds were not detected in chrome polluted soil. The log values of actinomycetes of eachsimilar to unpolluted soil. The investigation showed actinomycetes to be the major microbialpopulation inhabiting the mercury and chrome polluted soil. Thirty-one isolates among the total isolates were examined for antibacterial activity. Theseisolates were identified based on a phylogenetic analysis using 16S rRNA gene nucleotidesequences, they were categorized in three major phylogenetic groups, belong to the Streptomyces(6 strains), Saccharopolyspora(3 strains), Nocardiodes(1 strain). On the phylogenetic tree, theclade consisting of five isolates were distantly related to all of the established Streptomycetesgenera, indicating the possibility as members of new species.