Chemically defined and minimal media for Bacteroides gingivalis

A chemically defined medium (BGDM) has been developed specifically for Bacteroides gingivalis . The medium contains 4 amino acids, 5 mineral salts, cysteine hydrochloride as a reducing agent, and the growth factors hemin and menadione. Eight strains of B. gingivalis have been subcultured repeatedly in this medium with no apparent changes in colonial or cellular morphology. The metabolic end products of strains grown in this medium were reproducible and yielded patterns similar to those produced by cells cultured in complex media. When the defined medium was supplemented with protein hydrolysates such as trypticase, proteose peptone, bactocasitone, or yeast extract, at concentrations up to 1.0%, growth increased.