ABSTRACT
The inhibitory effect of ascorbic acid on Campylobacter jejuni is described. In vitro growth of clinical strains, as measured spectrophotometrically, was inhibited by 0.5 mg of freshly prepared L-ascorbic acid per ml. Alkaline-treated or aged L-ascorbic acid increased inhibition, as did copper; however, L-cysteine, L-cystine, and glutathione prevented inhibition. Biochemical analysis of the medium and cultures indicated that one or more of the oxidation products of L-ascorbic acid, e.g., L-dehydroascorbic acid or L-diketogulonic acid, were more effective inhibitors than was reduced L-ascorbic acid.
Subject(s)
Ascorbic Acid/metabolism , Campylobacter/growth & development , Campylobacter/metabolism , Culture MediaSubject(s)
Biocompatible Materials , Gingiva/cytology , Adult , Agar , Carbon , Cell Adhesion , Cell Line , Copper , Crystallization , Female , Glass , Gold , Humans , Polystyrenes , Silver , Titanium , VitalliumSubject(s)
Desmosomes/ultrastructure , Gingiva/ultrastructure , Animals , Cell Adhesion , Cell Line , Gingiva/cytologyABSTRACT
Growth of Mycoplasma pneumoniae was completely prevented by 0.06 mug of actinomycin D/ml, and 0.00375 mug/ml caused 90% inhibition. It thus appears that M. pneumoniae is more susceptible to actinomycin D than previously reported. Low concentrations (0.019 mug/ml) of the antibiotic primarily inhibited ribonucleic acid synthesis and high concentrations (20 mug/ml) inhibited both ribonucleic and deoxyribonucleic acid synthesis.
