Gelatin agar medium for detecting gelatinase production by anaerobic bacteria.
AUTOR(ES)
Whaley, D N
RESUMO
A new medium, Lombard-Dowell gelatin agar, was developed for detecting gelatinase activity by anaerobic bacteria. The medium contained: Trypticase (BBL Microbiology Systems), 5.0 g; yeast extract (Difco Laboratories), 5 g; sodium chloride, 2.5 g; sodium sulfite, 0.1 g; L-tryptophan, 0.2 g; L-cystine, 0.4 g; hemin, 10.0 mg; vitamin K1, 10.0 mg; agar, 20.0 g; D-glucose, 1.0 g; gelatin, 4.0 g; and distilled water to 1 liter. The pH was adjusted to 7.5. The medium was dispensed in 100- by 15-mm quadrant plastic dishes (5 ml per quadrant). To test for gelatinase activity, we inoculated the medium with a young enriched thioglycolate or chopped meat glucose broth culture or a turbid cell suspension in Lombard-Dowell broth, using a sterile cotton swab, and incubated it under anaerobic conditions for 48 h at 35 degrees C. The quadrants were then flooded with Frazier solution, and clear zones around the bacterial growth were recorded as positive for gelatinase activity. The new medium was tested with a variety of anaerobic bacteria, and the results were compared with data obtained with the conventional technique for detecting gelatinase activity. Overall, there was satisfactory agreement between the two tests in the detection of gelatinase activity, but the Lombard-Dowell gelatin agar tests was more rapid and somewhat more sensitive than the conventional test.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=272334Documentos Relacionados
- Modified agar dilution method for rapid antibiotic susceptibility testing of anaerobic bacteria.
- Comparison of three reagents for detecting indole production by anaerobic bacteria in microtest systems.
- Comparison of spiral gradient and conventional agar dilution for susceptibility testing of anaerobic bacteria.
- Production of branched-chain volatile fatty acids by certain anaerobic bacteria.
- National Committee for Clinical Laboratory Standards agar dilution susceptibility testing of anaerobic gram-negative bacteria.