Development of an additive for simple enhanced selectivity of selective agar plates for the detection of Legionella
Year: 2025
Type: article
Abstract: We previously developed a selective agar plate (CAT) for the detection of Legionella with enhanced selectivity (Inoue et al, 2006) .CAT agars contain cycloheximide, amphotericin B and thiabendazole as antifungal agents and vancomycin and polymyxin B as antibiotics.CAT agars have a high ability to inhibit non-target microorganisms and are effective in detecting Legionella such as retesting water samples where Legionella detection has failed due to the presence of nontarget microorganisms (Inoue et al, 2014) , but preparing CAT agars is not easy.We therefore tried to develop a CAT additive that can be spread on GVPC (Dennis et al, 1984) agars to produce CAT agars.The CAT additive for spreading on GVPC agars (Nikken Bio, Kyoto, Japan) was prepared by dissolving amphotericin B (AMPH, Sigma-Aldrich, St. Louis, Missouri, USA) and thiabendazole (TBZ, Tokyo Chemical Industry, Tokyo, Japan) in dimethyl sulfoxide (DMSO, Kishida Chemical, Osaka, Japan) and by dissolving vancomycin (VCM, Sigma-Aldrich) in water, and these solutions were mixed and diluted in DMSO (Table 1) .The final concentration of each agent is 8 mg/mL of AMPH, 4 mg/mL of TBZ, 0.4 mg/ mL of VCM, and 90% DMSO.The prepared CAT additive was stored in a freezer (-20℃) until use.One hundred microliters of the CAT additive was spread evenly on a GVPC agar plate by using a bacteria spreader to create a spread-CAT (sCAT) agar plate.The prepared sCAT agar plates were stored in a refrigerator (5℃) and used within one week.
Source: Journal of Microorganism Control
DOI: 10.4265/jmc.30.3_103
Authors: HIROAKI INOUE, MANAMI KITAZUME, YUKIE SAITO
Institution: Aquas Corporation (Japan)
Language: English
Subfield: Endocrinology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W4414600282