The capacity of subgingival microbiotas to produce volatile sulfur compounds in human serum

Hydrogen sulfide is formed by the subgingival microbiotas of periodontal pockets. The capacity of these microbiotas to form various volatile sulfur compounds in human serum was studied. Bacterial samples from nine deep periodontal pockets were incubated for 7 days in human serum and the amounts of volatile sulfur compounds and the degradation of serum proteins were determined. Hydrogen sulfide was the predominant volatile sulfur compound, but also methyl mercaptan was formed in significant amounts. Only traces of dimethyl sulfide and dimethyl disulfide were detected. There was an extensive degradation of the serum proteins. In most of the reaction mixtures hydrogen sulfide reached highly toxic levels.