Nutritional analysis and an enriched medium for fermentative treponemes isolated from subgingival plaque.

In order to cultivate fermentative treponemes isolated on Medium 10 with the plate-in-bottle method from subgingival plaque, we developed the enriched Medium 10. Enriched Medium 10 broth consisted mainly of Trypticase peptone (2 g/L), yeast extract (10 g/l), glucose (5 g/l) and volatile fatty acids mixture (3.1 ml/l). The growth curves in enriched Medium 10 broth showed that clinical isolates of Treponema socranskii reached the early stationary phase on the 3rd-5th day, and the doubling times averaged 22.2h. By using enriched Medium 10, the nutritional analysis of oral treponemes was examined for each compound of the volatile fatty acid and various sera. Clinical isolates were found to require iso-butyric acid, 2-methylbutyric acids and/or iso-caproic acid independently for their growth. However, the growth of these fermentative treponemes was inhibited by addition of various sera to this medium.