Entamoeba histolytica
Entamoeba histolytica is an anaerobic parasitic
amoebozoa, part
of the genus Entamoeba. Predominantly infecting humans and
other primates causing amoebiasis. Inside humans Entamoeba
histolytica lives and
multiplies as a trophozoite. Trophozoites are oblong and about 15–20 µm in
length. In order to infect other humans they encyst and exit the body. The life
cycle of Entamoeba histolytica does not require any intermediate
host. Mature cysts (spherical, 12–15 µm in diameter) are passed in the feces of
an infected human. Another human can get infected by ingesting them in fecally contaminated
water, food or hands.
Aspergillus sp.,
Aspergillus is a genus consisting of a few
hundred mold species found in
various climates worldwide. spergillum is an
asexual spore-forming structure common to all Aspergillus species; around
one-third of species are also known to have a sexual stage. Aspergillus is defined as a group
of conidial fungi—that is, fungi
in an asexual state
Human
and animal disease
Aspergillus
causes lung disease, called Aspergillosis,
Aspergillosis is, in particular, frequent among horticultural workers
who inhale peat dust,
which can be rich in Aspergillus spores. It has been found in
the mummies of ancient Egyptian tombs and can be inhaled when they are
disturbed
Industrial uses
Aspergillus is cultured for the industrial production of many
substances. Various strains of A. niger are used in the industrial preparation of citric acid (E330) and gluconic acid (E574) and have been assessed as acceptable for daily
intake by the World Health Organisation. A. niger fermentation is "generally recognized as
safe" (GRAS) by the United
States Food and Drug Administration under the Federal Food, Drug, and Cosmetic Act.
Many useful enzymes are produced using industrial fermentation of A. niger. For example, A. niger glucoamylase is used in the production of high-fructose corn syrup, and pectinases are used in cider and wine clarification.
Some Aspergillus species are
A.niger, A.flavus , Aspergillus fumigates, A. terreus
etc.,
Penicillium Sp.,
Penicillium is a genus of ascomycetous fungi of major importance in
the natural environment as well as food and drug production. Some members of
the genus produce penicillin, a
molecule that is used as an antibiotic, which
kills or stops the growth of certain kinds of bacteria inside the body. Other
species are used in cheesemaking.
The thallus (mycelium)
typically consists of a highly branched network of multinucleate, septate,
usually colorless hyphae.
Many-branched conidiophores sprout on the mycelia, bearing individually
constricted conidiospores. The
conidiospores are the main dispersal route of the fungi, and
often are green in color.
Economic Value :
Several species of the genus Penicillium play a central role in the production of cheese and of
various meat products. To be specific, Penicillium molds are found in Blue cheese. Penicillium camemberti and Penicillium roqueforti are the molds on Camembert, Brie, Roquefort, and many other
cheeses. Penicillium nalgiovense is used to improve the taste of sausages and hams, and
to prevent colonization by other molds and bacteria.[17]
In addition to their importance in the food industry, species of Penicillium and Aspergillus serve in the production of a number of
biotechnologically produced enzymes and other macromolecules, such as gluconic,
citric, and tartaric acids, as well as several pectinases, lipase, amylases,
cellulases, and proteases. Some Penicillium species have shown potential for use in bioremediation because of their ability to break down a variety of xenobiotic compounds.
The genus includes
a wide variety of species molds that are the source molds of major antibiotics. Penicillin, a drug produced
by P. chrysogenum (formerly P. notatum), was accidentally discovered by Alexander Fleming in 1929, and found to inhibit the growth of Gram-positive bacteria (see beta-lactams).
Rhizopus Sp.,
Rhizopus is a genus of common saprophytic fungi on plants and specialized parasites on animals. They are found on a wide variety of organic substrates, including "mature fruits and vegetables",[2] jellies, syrups, leather, bread, peanuts, and tobacco.
Rhizopus species grow as filamentous, branching hyphae that generally lack cross-walls (i.e., they are coenocytic). They reproduce by forming asexual and sexual spores. In asexual reproduction, sporangiospores are produced inside a spherical structure, the sporangium. Sporangia are supported by a large apophysate columella atop a long stalk, the sporangiophore. Sporangiophores arise among distinctive, root-like rhizoids. In sexual reproduction, a dark zygospore is produced at the point where two compatible mycelia fuse. Upon germination, a zygospore produces colonies that are genetically different from either parent.
· Rhizopus stolonifer (black bread mold) causes fruit rot on strawberry, tomato, and sweet potato and used in commercial production of fumaric acid and cortisone.
Chlamydomonas
Chlamydomonas is a genus of green
algae consisting
of unicellular flagellates,
found in stagnant water and on damp soil, in freshwater, seawater. It is generally
found in habitat rich in ammonium salt. Chlamydomonas possesses red eye spots for photosensitivity and
reproduces by both asexual and sexual means.
Chlamydomonas's asexual reproduction goes through
Zoospores, Palmella stage, Aplanospores and Hypnospores; sexual reproduction
through isogamy, anisogamy or oogamy.
Nutrition
Most species are obligate phototrophs but C. reinhardtii and C. dysosmos are facultative heterotrophs that can grow in the dark
in the presence of acetate as a carbon source.
Morphology
·
Motile unicellular algae.
·
Generally oval in shape.
·
Cell wall is made up of
glycoprotein and non cellulosic polysaccharides instead of cellulose.
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