Related Experiment Video
Updated: May 4, 2026

Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites
Published on: November 28, 2014
Inactivation of E. coli O157:H7 in cultivable soil by fast and slow pyrolysis-generated biochar
Joshua B Gurtler1, Akwasi A Boateng, Yanxue Helen Han
11 Food Safety and Intervention Technologies Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center , Wyndmoor, Pennsylvania.
Abstract:
An exploratory study was performed to determine the influence of fast pyrolysis (FP) and slow pyrolysis (SP) biochars on enterohemorrhagic Escherichia coli O157:H7 (EHEC) in soil. Soil + EHEC (inoculated at 7 log colony-forming units [CFU]/g of soil) + 1 of 12 types of biochar (10% total weight:weight in soil) was stored at 22°C and sampled for 8 weeks. FP switchgrass and FP horse litter biochars inactivated 2.8 and 2.1 log CFU/g more EHEC than no-biochar soils by day 14. EHEC was undetectable by surface plating at weeks 4 and 5 in standard FP switchgrass, FP oak, and FP switchgrass pellet biochars. Conversely, EHEC populations in no-biochar control samples remained as high as 5.8 and 4.0 log CFU/g at weeks 4 and 5, respectively. Additionally, three more SP hardwood pellet biochars (generated at 500°C for 1 h, or 2 h, or generated at 700°C for 30 min) inactivated greater numbers of EHEC than did the no-biochar control samples during weeks 4 and 5. These results suggest that biochar can inactivate E. coli O157:H7 in cultivable soil, which might mitigate risks associated with EHEC contamination on fresh produce.
Related Concept Videos
Microbial Bioremediation of Hydrocarbons
Microbial Bioremediation of Pesticides
Microbial Leaching
Stringent Response in E. coli
Bioremediation
Physical Methods for Controlling Microbial Growth: Temperature

