Ecological surveys of the Cryptococcus species complex in China.

BACKGROUND: Despite recent reports on the molecular epidemiology of cryptococcal infections in China, clinical isolates have been mostly reported from human immunodeficiency virus (HIV)-negative patients, and environmental isolates from China have rarely been included. The aim of this study was to investigate the ecological profile of Cryptococcus (C.) neoformans and C. gattii in China. METHODS: A survey was performed in 10 cities from 20°N (North latitude) to 50°N and in a Eucalyptus (E.) camaldulensis forestry farm at the Guixi forestry center, China. RESULTS: Six hundred and twenty samples of pigeon droppings from 10 cities and 819 E. camaldulensis tree samples were collected and inoculated on caffeic acid cornmeal agar (CACA). The brown-colored colonies were recultured to observe their morphology, growth on canavanine-glycine-bromothymol-blue (CGB) medium, phenol oxidase and urease activities, serotype and mating type. There were obvious differences in the positive sample rates of C. neoformans in pigeon droppings collected from the different cities, ranging from 50% in the cities located at latitudes from 30°N - 40°N, 29% at 20°N - 30°N and 13% at 40°N - 50°N. CONCLUSIONS: There were no differences in positive bevy rates (approximately 80%) among the three grouped cities. Mycological tests of 101 isolates purified from pigeon droppings revealed that they were C. neoformans var. grubii. We also observed variable capsular size around the C. neoformans cells in colonies with variable melanin production and the bio-adhesion of the natural C. neoformans cells with other microorganisms. One urease-negative C. neoformans isolate was isolated from pigeon droppings in Jinan city. No C. gattii was isolated in this study.

In Vitro Antifungal Activity of Epigallocatechin 3-O-Gallate against Clinical Isolates of Dermatophytes

Previously, we reported that epigallocatechin 3-O-gallate (EGCg) has growth-inhibitory effect on clinical isolates of Candida species. In this study, we investigated the antifungal activity of EGCg and antifungal agents against thirty-five of dermatophytes clinically isolated by the international guidelines (M38-A2). All isolates exhibited good susceptibility to EGCg (MIC50, 2-4 microg/mL, MIC90, 4-8 microg/mL, and geometric mean (GM) MICs, 3.36-4 microg/mL) than those of fluconazole (MIC50, 2-16 microg/mL, MIC90, 4-32 microg/mL, and GM MICs, 3.45-25.8 microg/mL) and flucytosin (MIC50, MIC90, and GM MICs, >64 microg/mL), although they were less susceptible to other antifungal agents, such as amphotericin B, itraconazole, and miconazole. These activities of EGCg were approximately 4-fold higher than those of fluconazole, and were 4 to 16-fold higher than flucytosin. This result indicates that EGCg can inhibit pathogenic dermatophyte species. Therefore, we suggest that EGCg may be effectively used solely as a possible agent or combined with other antifungal agents for antifungal therapy in dermatophytosis.

The Enzymatic Approach of Zygomycosis - Causing Mucorales / 대한의진균학회지

Various oxidases and hydrolytic enzymes were analyzed to investigate the relationship between these enzymes and the skin pathogenicity of 18 Mucorales strains. Each strain was cultured in a nutrient medium containing starch as a carbon source. The cells grew quickly and were at a good state of growth after incubation for three days. Oxidase activity was not detected in any strain, whereas Mucor spp. including Mucor racemosus IFM47053 typically had high alcohol dehydrogenase (ADH) activity and all the strains had catalase activity. The culture filtrate and the cell free extract of each strain were applied to APIZYM test system, which revealed that all the strains examined produced many hydrolytic enzymes both inside and outside their mycelia. In the case of Absidia corymbifera strains, lipase activity was comparatively high, and polysaccharide hydrolytic enzymes such as alpha-glucosidase, beta-glucosidase, N-acetyl-beta-glucosaminidase, alpha-mannosidase, and alpha-fucosidase were produced.