Stress-related salivary proteins affect the production of volatile sulfur compounds by oral bacteria.

Objective: To determine whether stress-related substances and sex hormones influence the growth and in vitro production of volatile sulfur compounds (VSCs) by Solobacterium moorei and Fusobacterium nucleatum.

Materials And Methods: Bacteria growth and VSCs production were evaluated in the presence of alpha-amylase, beta-defensin-2, mucin, estradiol, and progesterone. Growth was evaluated by colony counting, and the production of the VSCs hydrogen sulfide (H S) and methyl mercaptan (CH SH) was measured using the Oral Chroma™ instrument.

Results: Mucin induced the production of H S by both bacteria, but had a slight inhibitory effect on CH SH production by F. nucleatum. It also increased the viability of F. nucleatum. Alpha-amylase increased H S production by S. moorei and CH SH production by F. nucleatum, but had no effect on H S production by F. nucleatum. No substance altered the viability of S. moorei. No effects of beta-defensin-2, estradiol, or progesterone were observed.

Conclusion: The salivary stress-related proteins mucin and alpha-amylase altered VSCs production by F. nucleatum and S. moorei, favoring H S production. These findings are a step toward understanding the relation between stress and increased amounts of H S.