T88 Geomicrobiology of Arsenic Transformation and Mobilization in Arsenic-Enriched Alluvial Aquifers and Subsequent Impact on Ecosystem as Well as Human Health

Monday, 1 November 2010
8:00 AM - 12:00 PM
Mile High Ballroom 1AB

POTENTIAL ROLE OF ARSENIC REDUCTION [AS(V) TO AS(III)] BY OSBH2 (PSEUDOMONAS STUTZERI) AND OSBH5 (BACILLUS CEREUS) IN OIL-CONTAMINATED SITE

Paper number: T88-10
Program: Technical Sessions
Time: 10:20 AM – 10:35 AM

Authors

Abstract

Microbial reduction of arsenate [As(V)] plays an important role in arsenic (As) mobilization in aqueous environment. In this study, we investigated reduction characteristics of arsenate by different bacterial isolates such as OSBH1 (GU329913), OSBH2 (GU329914), OSBH3 (GU329915), OSBH4 (GU329916) and OSBH5 (GU329917), isolated from oil sludge of sewage treatment plant, China Petroleum Refinery Company in Kaohsiung, southern Taiwan. Bacterial strains of pure culture were identified by 16S-rRNA analysis (≥99% similarity). Morphological and 16S-rRNA analysis exhibits that the isolate OSBH1 is similar to E. coli, OSBH2 to P. stutzeri, OSBH3 to P. Putida, OSBH4 to P. aeruginosa, and OSBH5 to B. Cereus. The results also exhibited that isolates OSBH2 and OSBH5 reduced efficiently As(V) to As(III). The rate of arsenic reduction was found higher in the presence of OSBH5 isolate than in the presence of OSBH2 isolate. Also, the microbial growth (cell/ml) of OSBH5 was noticed higher in the As(V) culture medium than that of OSBH2. The bacteria isolates such as OSBH1, OSBH3 and OSBH4 were found not capable of reducing arsenate or oxidation of arsenite. It is concluded that the activity of the described oil degrading bacterial isolates contributes to the mobilization of arsenic in the more toxic As(III) form and which affects the biotic life.