Differences between Yeasts and Molds

The major differences between Yeasts and Molds are:

S.N.	Character	Yeasts	Molds
1.	Definition	Yeast is a unicellular, budding fungus.	Mold is a multicellular, threadlike fungus.
2.	Form	Grow as large single cells.	Grow as multiple tubular branches.
3.	Cell type	Unicellular	Multicellular
4.	Habitat	Very common. It can be found on fruit and berries, in the stomachs of mammals and on the skin, among other places.	Typically found in damp, dark or humid areas.
5.	Appearance	White and thready. Usually oval in shape.	Mold has a fuzzy appearance and can be found in several shapes.
6.	Hyphae	Yeasts do not have true hyphae. Instead, they form multicellular structures called pseudo-hyphae.	Molds have microscopic filaments called hyphae.
7.	Spore	Yeast is a not a sporing species of fungi.	Mold is a sporing fungus
8.	Colony morphology	Yeast colonies are soft, opaque and cream-colored.	Filamentous type colony with vegetative hyphae and aerial hyphae.
9.	Color	Yeasts are less colorful compared to molds (colorless).	Molds are very colorful and maybe orange, green, black, brown, pink or purple.
10.	Incubation Temperature	Routine incubation temperature is usually 25oC to 30oC (room temperature).	Routine incubation temperature is usually 25o to 30o C, although 35o C incubation can be used to differentiate some molds based on temperature tolerance or to determine whether organisms are diphasic.
11.	Cultivation time	These organisms usually grow within 24 to 36 hours after inoculation on media.	These organisms usually grow more slowly than yeasts after inoculation to media.
12.	Aerobic/Anaerobic	Yeast can grow in aerobic as well as in anaerobic conditions.	Molds grow only in aerobic conditions.
13.	pH range for growth	Growth limited to a pH range of 4.0 to 4.5.	Mold can grow in a wider range of acidity (pH) levels than yeasts.
14.	Diagnosis/ Identification	Identification bases on physiologic tests and a few key morphologic differences.	Most clinical molds can be determined by microscopic examination of the ontogeny and morphology of their asexual spores.
15.	Reproduction	Most reproduce asexually through mitosis. The most common form called “budding.” A smaller number of yeasts reproduce by binary fission.	Reproduce through small spores, which can be either sexual or asexual.
16.	Asexual Spores	Blastospore	Sporangiospores and Conidia
17.	Sexual Spores	No Sexual Spores.	Zygospores, Ascospores, and Basidiospores
18.	Energy Production	Convert carbohydrates to alcohol and carbon dioxide in anaerobic through fermentation. Also, obtain carbon from hexose sugars.	Secrete hydrolytic enzymes that degrade biopolymers such as starch, cellulose, and lignin into simpler substances that can be absorbed.
19.	Health risks	It can cause infection in individuals with compromised immune systems.	It can cause allergic reactions and respiratory problems.
20.	Other risks	Comparatively less involved in spoilage.	Molds cause a greater threat in terms of food spoilage and sanitation concerns, particularly in fresh produce.
21.	Uses	Ethanol production, baking, vitamin supplements, the study of the cell cycle.	Some molds are used in food production, for example, Penicillium is used in the production of cheese, Neurospora in the production of oncom, which is made from the by-product of tofu. Mold is also a crucial saprophyte.
22.	Species	1500 known species – 1% of all fungi.	There are 400,000 types of molds.
23.	Examples	Saccharomyces cerevisiae, Cryptococcus neoformans, etc.	Alternaria, Aspergillus, Fusarium, Mucor, Penicillium, Rhizopus, Trichophyton, etc.