SOME BIOTECHNOLOGICALLY IMPORTANT FUNGI
FILAMENTOUS SPECIES -
Most of the filamentous fungi that are important in biotechnology are members of the important in biotechnology are members of the Deuteromycetes (Deuteromycotina). Examples include Aspergillus niger, pencillum notatum – chrysogenum & Trichoderma Viridae. Basidiomycetes white rot fungi such as phanerochaete Chrysosporum are becoming increasingly important in environmental biotechnology because they are able to metabolise a variety of organic chemicals, many of which are pollutants.
-ASPERGILLUS SPP. -
There are about 200 species of Aspergillus, found throughout the world growing on a vast array of substrates. Aspergillus niger, as its specific name suggests, is a black fungi which is commonly called ‘black mould’. Many Aspergilli contaminate foods, producing toxic products;A flavours for example, produce the mycotoxin alfatoxin. Several species also grow as contaminants on leather & cloth. Aspergillus species are important in medicine, causing disease of the internal organs. Aspergillus fumigatus accounts for nearly all of these infections. Aspergillus species produce numerous extracellular enzymes, many of which are put to good use in biotechnology. Aspergillus niger is particularly important in the manufacture of citric acid & gluconic acid, both finding wide application in food industry.
The asexual stage of Aspergillus is the one most often encountered by biotechnologists.
-PE NICILLIUM SPP. -
- TRICHODERMA SPP. - Trichoderma species are ubiquitous soil fungi which produce white, yellow or green colonies when cultured. Trichoderma species are used to produce cellulases. They are particularly effective as antagonists of the growth of other fungi, many of them plant pathogens, with the result that trichoderma species are important biocontrol agents.Penicillin species are as widespread & cosmopolitan as the aspergilli. They are frequently referred to as green or blue moulds & are often found contaminating citrus fruits or causing decay on refrigerated cheese & other foodstuffs. Various species are also pathogenic to citrus fruits. Like members of the genus Aspergillus, penicillin species also attack leather & fabrics. The production of penicillin is without doubt the most significant use of this fungus. The only other therapeutically useful antibiotic produced by members of this genus is griseofulvin, which is used to treat fungal infections of the skin, including athelet’s foot. Penicillium species also produce organic acids & flavours cheeses.
- PHANEROCHAETE CHRYSOSPORIUM – It is a member of the Basidiomycetes but it is the filamentous stage rather than the sporophore that is used in biotechnology. It belongs to a group called the white rot fungi, a name that emphasises the importance of these fungi as agents of wood decay. It is noteworthy for its ability to produce non-specific ligninases which can be used to degrade pollutants both in liquid effluents & in soils.
Yeasts play a fundamentally important role in biotechnology. The classic yeasts are unicellular & are slimy in appearance when growing on media often resembling bacterial colonies. Saccharomyces species are widely used in the food industry in bread production & in the fermentation of alcoholic beverages. Yeasts have also been used as source of single-cell protein, and to produce alcohol for industrial purposes. Recent developments in the molecular biology of yeasts have significantly expanded the biotechnological potential of these fungi.
-TABLE- INDUSTRIAL APPLICATIONS OF YEASTS ORGANISM USE
1. Saccharomyces Cerevisiae Brewing, baking, fuel, alcohol,wine 2. Saccharomyces uvarum Brewing, melibiase 3. Ashbya gossypii,Eremothecium ashbyii Riboflavin 4. Rhadotorula Carotene 5. Hansenula, Pichia SCP Via methanol 6. Yarrowia Lypolytica Citric acid 7. Saccharomycopsis,Aureobasidium D-Gluconic acid
- ASARICUS SPP. - Agarius spp. are almost exclusively used in biotechnology for the production of mushrooms i.e. as a protein rich foodstuff. The commercial species used in mushroom growing in almost exclusively A bisporus.
- CLAVICEPS PURPUREA -
It is an Ascomycete notable for producing sclerotia, called ergot, from which a number of valuable, pharmacologically useful alkaloids are extracted.