All About Mould
Mold \Mold\, Mould \Mould\, n. [From the p. p. of OE. moulen to become moldy, to rot, prob. fr. Icel. mygla to grow musty, mugga mugginess; cf. Sw. m[“o]gla to grow moldy. See Muggy, and cf. Moldy.] (Bot.) A growth of minute fungi of various kinds, esp. those of the great groups Hyphomycetes, and Physomycetes, forming on damp or decaying organic matter. Note: The common blue mold of cheese, the brick-red cheese mold, and the scarlet or orange strata which grow on tubers or roots stored up for use, when commencing to decay, are familiar examples. — M. J. Berkley.
Mold (fungi), fuzzy, cobweblike growth produced on organic matter by several types of fungi. Mold and mildew are commonly used interchangeably, although mold is often applied to black, blue, green, and red fungal growths, and mildew to whitish growths.
Black bread mold, Aspergillus niger, one of the most familiar molds, begins as a microscopic, airborne spore that germinates on contact with the moist surface of nonliving organic matter. It spreads rapidly, forming the mycelium (fungal body), which is made up of a fine network of filaments (hyphae). The mycelium produces other clusters of rootlike hyphae, called rhizoids, which penetrate the organic material, secreting enzymes and absorbing water and the digested sugars and starches. Other clusters of hyphae called sporangiophores then reach upward, forming sporangia (knoblike spore cases), which bear the particular color of the mold species. Upon ripening, the sporangia break open and the windborne spores land elsewhere to reproduce asexually.
Some molds also reproduce sexually through conjugation of gamete cells by the joining of two specialized hyphae. The resulting zygote matures into a zygospore that germinates after a dormant period.
Molds thrive on a great many organic substances and, provided with sufficient moisture, they rapidly disintegrate wood, paper, and leather. In fruit the enzymes penetrate well behind the area of the visible growths to damage the fruit. Besides being destructive, however, molds also have many industrial uses, such as in the fermentation of organic acids and cheeses. Camembert and Roquefort cheeses, for example, gain their particular flavors from the enzymes of Penicillium camemberti and P. roqueforti, respectively. Penicillin, a product of the green mold P. notatum, revolutionized antibiotic drugs after its discovery in 1929, and the red bread mold Neurospora is an important tool in genetic experiments.
Main Entry: blue mold
Date: 1664 : any of various fungi (genus Penicillium) that produce blue or blue-green surface growths
Main Entry: bread mold
Date: 1914 : any of various molds found especially on bread; especially : a rhizopus (Rhizopus nigricans syn. R. stolonifer)
Main Entry: green mold
Date: 1919 : a green or green-spored mold (as of the genera Penicillium or Aspergillus)
Main Entry: leaf mold
Date: 1845 1 : a compost or layer composed chiefly of decayed vegetable matter 2 : a mold or mildew that affects foliage
Main Entry: slime mold
Date: 1880 : any of a group (Myxomycetes or Mycetozoa) of organisms usually held to be lower fungi but sometimes considered protozoans that exist vegetatively as mobile plasmodia and reproduce by spores
Main Entry: sooty mold
Date: 1901 : a dark growth of fungus mycelium growing in insect honeydew on plants; also : a fungus producing such growth
Main Entry: water mold
Date: 1899 : an aquatic fungus (as of the genus Saprolegnia)
Mold, a common term for fungus, are microscopic organisms that produce enzymes to digest organic matter and produce large quantities of spores for reproduction. Mold attacks organic materials such as: Paper, Cloth, Leather, Wood, Books, Photographs, Drywall, Wallpaper.
Mold grows from spores that are found everywhere in our environment. Usually spores are inactive, but when the relative humidity exceeds seventy percent (70%) they will germinate and multiply rapidly. Research indicates that there are more than 1,000 different species of mold around the world. Mold organisms are part of the fungi kingdom, a realm shared with mushrooms, yeast and mildews. In nature, mold plays a key role in the decomposition of leaves, wood, and other plant debris. Without mold we would find ourselves wading neck deep in dead plant matter.
Two of the worst features of mold spores are:
- They are microscopic and therefore extremely difficult to filter out of the air
- Spores are able to stay suspended in air for hours making them easily inhaled by building occupants
Essential Items for Mold Growth
- Food Source: leaves, wood, insulation, drywall, carpeting, clothing, paper, soil
- Moisture: any source of moisture lasting or recurring for a period of at least 24 to 48 hours.
- Moisture sources include: flooding, damp basements, house plants, wet clothes on indoor drying lines, combustion appliances (such as stoves), shower and bathroom steam and/or leaks, steam from kitchens, backed-up sewers, leaky roof, plumbing leaks, humidifiers, mud or ice
Mold can be found in:
- Any moist areas in your home
- Ventilation systems
Penicillin; the forgotten background
It is often thought that Fleming discovered penicillin by chance. This is not quite so. He and his colleagues had been looking for many years for a good killer of bacteria that would not equally kill living tissues. Fleming was working at the Institute of Pathology headed by Almroth Wright at St Mary’s Hospital, London. His training in bacteriology was under Almroth Wright. In 1896 Almroth Wright had developed a vaccine against typhoid fever. He was interested in the mechanisms and efficacy of the body’s natural defense mechanisms against infection.
In the 1914-18 war the wounded soldiers were dying from tetanus and gangrene. The open wounds of soldiers were being medically treated with disinfectants and antiseptics such as carbolic acid, iodine, and hypochlorites. These substances were very effective in vitro in sterilizing surgical equipment but Wright found that on wounded soldiers they generally made the infection worse! They killed the body’s natural defenses quicker than they killed the bacteria.
In 1921 Fleming found that saliva and tears contained something that killed Micrococcus bacteria. He called this substance “lysozyme” and found that it was also present on the skin, finger nails and milk and other body fluids. Unfortunately it was not very effective against pathogenic bacteria. He was still looking for effective agents and in 1928 noted that pathogenic staphylococci were killed by a mould growing on one of his culture plates. He identified the mould as Penicillium notatum and in 1928 published a paper on the effect of an extract of the mould on pathogenic bacteria. He called the extract “penicillin”.
Later Florey and Chain purified the extract and made it more effective against pathogenic bacteria with less side effects against man. It was the beginning of the age of Antibiotics.
“Chance favours the prepared mind” – Pasteur