Genus/species (aliases): Candida tropicalis (Atelosaccharomyces tropicalis, Candida albicans var. tropicalis, Castellania tropicalis, Monila tropicalis, Oidium tropicale, and Procandida tropicalis)
Classification: Ascomycete; anamorph
Morphology:
Cell: reproduce by budding; spherical to ovoid, 3.0-5.5 x 4.0-9.0 um; pseudohyphae and hyphae may be formed
Colony:
- YPD: off-white to grey, cream –colored, dull, soft, smooth and creamy or wrinkled and tough
- Malt agar: White to cream color, smooth, glabrous, fringed border WL = Positive on cycloheximide 0.1
- Spore: Blastospores produced on pseudohyphae, singly, in chains or clusters; Arthroconidia and ballistoconidia are not formed.
- Zygote: NA
- Ascus: NA
Liquid Growth: Subglobose to ovoid, single and paired, can make thin surface film and bubbles in Sabourand broth; sediments can be formed
Physiological Traits:
- Fermentation: Glucose, Maltose, Galactose, Trehalose, Raffinose; Sucrose variable.
- Assimilation: Galactose, Maltose, Trehalose, Soluble starch, Succinate, D-Xylose, Arabinose, D-Mannitol, D-Glucitol; variable: Cellobiose, Citrate, Glycerol, Lactate, Ribitol, Salicin, Sucrose, L-Sorbose, Melezitose, Ribose; No assimilation of nitrate; no growth in vitamin free medium: requires biotin; uses as sole N source: Ethylamine, Lysine, Cadaverine
- Growth at 37 C: +; some strains will grow at 40 and 42 C
- Growth sensitivities: will grow on 0.01% and (some strains) 0.1% cycloheximide
- Chromosome bands: 4 to 12 reported
Ecological Traits:
Found on human skin mucous membranes, gut flora, soil, fermentation vats, water, leaves, raw honey and flowers; rarely found in wine when found, likely evidence of human contamination perhaps during plating.
Distinguishing Features:
Unlike physiologically similar C. maltose, C. tropicalis can assimilate starch. Unlike C. sake, it can grow at 35° C. inositol -, nitrate -, erythritol -.
Role in wine: Genus Candida is known to grow during first few days of fermentation at which point they die off
Sensitivities:
- SO2:
- Sorbate:
- DMDC:
- Optimum pH: 3.5-6.6
- Ethanol: 0.85M
- Anaerobiosis:
- Optimum Heat: 20 to 45°C