[Study on growth characteristics of under different conditions and its toxicity].

Objective: To investigate the characteristics of growth and metabolism and the toxicity of under different conditions.

Methods: We observed the growth of and under routine culture conditions and in different pH and salt concentrations, and compared their activities of sugar fermentation using microbiochemical reaction tubes. Four-week-old nude mice were randomized into infection group (=5), infection group (=5) and control group (=5) for intragastric administration of 0.3 mL suspension the two (5×10 cfu/mL) or 0.3 mL normal saline. Samples of the liver, kidney, intestine, feces and blood were taken for analysis of the distribution and toxicity of by fungal culture and histopathological examination.

Results: exhibited logarithmic growth at 8-24 h after inoculation and showed stable growth after 24 h. showed optimal growth within the pH value range of 5-7 with a growth pattern identical to that of . grew better than in media containing 5% and 10% NaCl, and could ferment glucose, sucrose, trehalose and sorbitol. could be isolated from the feces, blood, liver and kidney of infected nude mice, and the liver had the highest fungal load (5.7 log cfu/g). could cause pathological changes in the liver and intestine of the mice, but with a lesser severity as compared with .

Conclusions: exhibits optimal growth in mildly acidic or neutral conditions with a high salt tolerance, and can potentially penetrate the intestinal barrier into blood and lead to tissue injuries in hosts with immunosuppression.