• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.435-443
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• 1987

A total of 30 strains of Candida albicans were examined for susceptibility to amphotericin B and ketoconazole using Sabouraud's dextrose broth, Kimmig broth and Supplemented yeast nitrogen base broth media. Furthermore, the growth curve and colony forming units were checked for use of stationary-phase cells and 2-hour incubation cells in the absence of atifungal agents. The viable counts were determined periodically during incubation by standard plate count techniques. The minimum inhibitory concentrations of amphotericin B for use of stationary phase cells were as follows: SDB, $0.09{\sim}0.97mcg/ml$(0.39mcg/ml); Kimmig broth, $0.19{\sim}0.39mcg/ml$(0.42 mcg/ml) and SYNB, $0.19{\sim}0.39mcg/ml$mcg/ml(0.23mcg/ml). In ketoconazole, MICs were value SDB, $3.12{\sim}25.0mcg/ml$(12.5mcg/ml); Kimmig broth, $12.5{\sim}25.0mcg/ml$ (22.5mcg/ml) and SYNB, $3.12{\sim}12.5mcg/ml$(6.71mcg/ml). The MICs of amphotericin B(0.2mcg/ml cone.) for use of 2-hour incubation cells in absence of AMB were, SDB, $0.04{\sim}0.39mcg/ml$(0.11mcg/ml); Kimmig broth, $0.09{\sim}0.39mcg/ml$(0.18mcg/ml) and SYNB, $0.09{\sim}0.19mcg/ml$(0.14mcg/ml) and in KTZ, the value of MICs were SDB, $3.12{\sim}25.0mcg/ml$(12.22mcg/ml); Kimmig broth, $0.78{\sim}25.0mcg/ml$(11.01mcg/ml) and SYNB, $1.56{\sim}12.5mcg/ml$(3.90mcg/ml). The two-log reductions in CFU per milliliter observed when 2 hour preincubation cells were treated with 0.2mcg/concentrations of AMB and 25.0mcg/ml of KTZ. However, AMB treated cells were restored to growth activity, it suggested that the AMB has no active antifungal activity.

• Journal of Life Science
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• v.30 no.2
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• pp.178-185
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• 2020

Rice bakanae is a typical seed-borne and seed-transmitted disease caused by infection by Fusarium fujikuroi. Seed disinfection using chemical fungicides (such as benomyl and prochloraz) is most effective in controlling the disease, but the emergence of fungicide-resistant strains has recently been increasing. Slightly acidic hypochlorous acid water (SAHW) is a safe and environmentally friendly disinfectant that has a potent and broad spectrum of antimicrobial activity against viruses, bacteria, and fungi. In this study, we aimed to investigate the effectiveness of SAHW against F. fujikuroi strains, including chemical fungicide-resistant strains, as an alternative to conventional chemical fungicides in the management of bakanae disease. SAHW showed strong but similar levels of antifungal activity among the F. fujikuroi strains with a minimum inhibitory concentration (MIC₉₀) of 5±2.5 ppm of free available chlorine (FAC). In addition, F. fujikuroi cells lost viability completely within 5 min of SAHW treatment due to the lethal damage to cell integrity. When the rice seeds infected by F. fujikuroi were treated with SAHW containing 20±10 ppm of FAC for 12 hr, the efficiencies of seed disinfection and disease control were 95-98% and 90.1-92.6%, respectively. Altogether, our data suggest that SAHW is an effective compound for controlling rice bakanae disease.