Mold
The dusty texture of many molds is caused by profuse production of asexual spores (conidia) formed by differentiation at the ends of hyphae.
Molds are considered to be microbes and do not form a specific taxonomic or phylogenetic grouping, but can be found in the divisions Zygomycota and Ascomycota.
[1] There are thousands of known species of mold fungi with diverse life-styles including saprotrophs, mesophiles, psychrophiles and thermophiles, and a very few opportunistic pathogens of humans.
In this way, molds play a major role in causing decomposition of organic material, enabling the recycling of nutrients throughout ecosystems.
Some molds produce small, hydrophobic spores that are adapted for wind dispersal and may remain airborne for long periods; in some the cell walls are darkly pigmented, providing resistance to damage by ultraviolet radiation.
Although molds can grow on dead organic matter everywhere in nature, their presence is visible to the unaided eye only when they form large colonies.
In artificial environments such as buildings, humidity and temperature are often stable enough to foster the growth of mold colonies, commonly seen as a downy or furry coating growing on food or other surfaces.
When conditions do not enable growth to take place, molds may remain alive in a dormant state depending on the species, within a large range of temperatures.
Certain molds can survive harsh conditions such as the snow-covered soils of Antarctica, refrigeration, highly acidic solvents, anti-bacterial soap and even petroleum products such as jet fuel.
Koji molds break down the starch in rice, barley, sweet potatoes, etc., a process called saccharification, in the production of sake, shōchū and other distilled spirits.
[14] A study has shown that red rice yeast used as a dietary supplement, combined with fish oil and healthy lifestyle changes, may help reduce "bad" cholesterol as effectively as certain commercial statin drugs.
[16] Some sausages, such as salami, incorporate starter cultures of molds [17] to improve flavor and reduce bacterial spoilage during curing.
[18][19][20] Fleming continued to investigate penicillin, showing that it could inhibit various types of bacteria found in infections and other ailments, but he was unable to produce the compound in large enough amounts necessary for production of a medicine.
This team was also unable to produce the pure compound in any large amount, and found that the purification process diminished its effectiveness and negated the anti-bacterial properties it had.
Symptoms caused by mold allergy are: watery, itchy eyes; a chronic cough; headaches or migraines; difficulty breathing; rashes; tiredness; sinus problems; nasal blockage and frequent sneezing.
Some species produce toxic secondary metabolites, collectively termed mycotoxins, including aflatoxins, ochratoxins, fumonisins, trichothecenes, citrinin, and patulin.
Interior mold colonization can lead to a variety of health problems as microscopic airborne reproductive spores, analogous to tree pollen, are inhaled by building occupants.
[30] Determination of airborne spore counts is accomplished by way of an air sample, in which a specialized pump with a known flow rate is operated for a known period of time.
[33] The United States Environmental Protection Agency (EPA) currently recommends that relative humidity be maintained below 60%, ideally between 30% and 50%, to inhibit mold growth.
Daniele Del Nero, for example, constructs scale models of houses and office buildings and then induces mold to grow on them, giving them an unsettling, reclaimed-by-nature look.
[37] Sam Taylor-Johnson has made a number of time-lapse films capturing the gradual decay of classically arranged still lifes.
