A Sensitive Visual Method for the Detection of Hydrogen Sulfide Producing Bacteria

Hydrogen sulfide (H2S) is a toxic gas produced by bacteria in the proteolysis of sulfur-containing amino acids and proteins that plays an important role in human health. The H2S production test is one of the important bacterial biochemical identification tests. The traditional methods are not only tedious and time-consuming but also prone to inhibition of bacterial growth due to the toxic effect of heavy metal salts in sulfur-containing medium, which often leads to negative results. Here, we established a simple and sensitive method to detect H2S in bacteria. This method is a modified version of bismuth sulfide (BS) precipitation that uses 96-well transparent microtiter plates. Bacterial culture was combined with bismuth solution containing L-cysteine and cultivated for 20 min, at the end of which a black precipitate was observed.The visual detection limit for H2S was 0.2 mM. Based on the visual color change, the simple, high-throughput, and rapid detection of H2S producing bacteria can be achieved. In summary, this method can be used to identify H2S production in bacteria.