Effect of different air flow rate on operation of sulfur-oxidizing bacteria (SOB) biosensor

• Published in: Geosystem engineering Vol. 18; no. 5; pp. 245 - 250
• Main Authors: Gurung, Anup, Shin, Beom-Soo, Oh, Sang-Eun
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 03.09.2015; 한국자원공학회
• Subjects: biosensor; inhibition; sulfate; sulfur-oxidizing bacteria; toxicity; wastewater; 자원공학
• ISSN: 1226-9328; 2166-3394
• DOI: 10.1080/12269328.2015.1047964

Recently, sulfur-oxidizing bacteria (SOB) has been used as a bioindicators for detecting heavy metals and other toxic chemicals in water. The methodology exploits the ability of SOB to oxidize elemental sulfur to sulfuric acid under aerobic condition and results in an increase in electrical conductivity (EC) and a decrease in pH. Thus, the typical monitoring of SOB biosensor is based on the measurement of EC and pH of the medium. In this study, effect of different air flow rate (200, 300, and 400 ml min − 1 ) on activity of SOB has been evaluated. It was found that 400 ml min − 1 of air flow rate gave the best performance. At this air flow rate, the EC value increased by 9.9% and 2.3% as compared to 200 and 300 ml min − 1 , respectively. However, at high flow rate, the EC value could be influenced by evaporation. Ag 2+ was used as the reference toxicant in the experiment. The EC 50 of Ag 2+ for 1 and 2 h was 2.3 ± 1.9 and 3.62 ± 2.4 mg l − 1 , respectively.