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Aloe (реферат)

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Aloe

Aloe vera

Aloe is a HYPERLINK “http://en.wikipedia.org/wiki/Genus” \o “Genus”
genus of HYPERLINK “http://en.wikipedia.org/wiki/Succulent_plant” \o
“Succulent plant” succulent , HYPERLINK
“http://en.wikipedia.org/wiki/Flowering_plant” \o “Flowering plant”
flowering plants in the family HYPERLINK
“http://en.wikipedia.org/wiki/Asphodelaceae” \o “Asphodelaceae”
Asphodelaceae , which contains about 400 different HYPERLINK
“http://en.wikipedia.org/wiki/Species” \o “Species” species . They are
native to the drier parts of HYPERLINK
“http://en.wikipedia.org/wiki/Africa” \o “Africa” Africa , especially
HYPERLINK “http://en.wikipedia.org/wiki/South_Africa” \o “South Africa”
South Africa ‘s HYPERLINK “http://en.wikipedia.org/wiki/Cape_Province”
\o “Cape Province” Cape Province and the mountains of tropical Africa.

Members of the closely allied genera HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Gasteria&action=edit” \o
“Gasteria” Gasteria and HYPERLINK
“http://en.wikipedia.org/wiki/Haworthia” \o “Haworthia” Haworthia ,
which have a similar mode of growth, are also sometimes popularly known
as aloes. Note that the plant sometimes called “American aloe”, Agave
americana, belongs to a different family, namely HYPERLINK
“http://en.wikipedia.org/wiki/Agavaceae” \o “Agavaceae” Agavaceae .

Aloe plants are stiff and rugged, consisting mainly of a rosette of
large, thick, fleshy HYPERLINK “http://en.wikipedia.org/wiki/Leaf” \o
“Leaf” leaves . Many common varieties of Aloe are seemingly stemless,
with the rosette growing directly at ground level; Other varieties may
mave a branched or un-branched HYPERLINK
“http://en.wikipedia.org/wiki/Stem” \o “Stem” stem from which the
fleshy leaves spring. The leaves are generally lance-shaped with a sharp
apex and a spiny margin. They vary in color from grey to bright green
and are sometimes striped or mottled.

Aloe HYPERLINK “http://en.wikipedia.org/wiki/Flower” \o “Flower”
flowers are small, tubular, and yellow or red and are borne on densely
clustered, simple or branched leafless stems. The plants are cultivated
as ornamental plants, especially in public buildings and gardens.

Uses

Human use of Aloes is primarily as an herbal in alternative medicines
and “home first aid”. Both the translucent inner plup as well as the
resinous yellow exudate from wounding the Aloe plant is used externally
to relieve skin discomforts and internally as purgatives. To date,
research has show in certain cases that Aloes produce positive medicinal
benefits for healing damaged skin, however there is still much debate
regarding the effectiveness and safety for using Aloes medicinally in
other manners.

Some Aloes have been used for human consumption. For example drinks made
from or containing chunks of aloe pulp are popular in Asia as commercial
beverages, and as a tea additive. This is notably true in HYPERLINK
“http://en.wikipedia.org/wiki/Korea” \o “Korea” Korea . As well, the
yellow exudate from the leaves were once used on children’s fingers to
stop nail-biting.

External uses

The most common uses of aloe vera have been from topical use on human
skin to treat various conditions. Aloe vera is also often used to treat
skin from burns. Not only does it soothe the skin, ease pain and reduce
inflammation, studies have been done to show that using aloe as a
topical treatment to burns will help speed up the healing recovery
process. A study performed in the 1990s showed that the healing of a
moderate severe burn was sped up by six days when covering the wound on
a regular basis with aloe vera gel, compared to the healing of the wound
covered in a gauze bandage (Farrar, 2005). Aloe vera not only helps
burns of various degrees, it also has become a common relief aid in
treating sunburns. This is often the most common known use of the plant
and the rubbing of aloe vera leaves onto sun-burned skin dates back to
civilizations such as the Mayas and the Incas ( HYPERLINK
“http://www.newstarget.com/001560-02.html” \o
“http://www.newstarget.com/001560-02.html”
http://www.newstarget.com/001560-02.html ). Today this relief product is
still used for the same purpose, yet can be found in drugstores in a gel
form. When rubbed over over-exposed skin, the redness will disappear
within a couple of days and helps to preserve moisture so that the skin
will not become dry and peel.

Aloe vera can also be used to treat minor cuts and scrapes. Using an
aloe vera leaf and rubbing it over a cut will help prevent infection and
will speed up the healing response from the body. The aloe vera acts as
a sealant and pulls the skin back together like a bandage or a suture (
HYPERLINK “http://www.newstarget.com/001560-02.html” \o
“http://www.newstarget.com/001560-02.html”
http://www.newstarget.com/001560-02.html ). Although aloe should not be
used as a substitute for medical treatment, its many uses are beneficial
and should be considered for anything such as an everyday moisturizer to
a first-aid antiseptic. In addition to the above-mentioned benefits,
continueous research is being done to learn how else the aloe vera plant
can play an important part in human lives.

Many cosmetic companies are now adding this plant to every product
possible including makeup, soaps, sunscreens, shampoos and lotions, as
well as any product that is created to soothe, protect and moisturize
the skin. This is due partiall to fact that Aloe extract is full of
vitamins, nutrients and minerals, as well as, the perception of the
general public of Aloe as a healing ingrediant. The International Aloe
Science Council advises choosing products that contain between
twenty-five and forty percent aloe in them to receive the ultimate aloe
vera benefits to the skin ( HYPERLINK “http://www.iasc.org/aloe.html”
\o “http://www.iasc.org/aloe.html” http://www.iasc.org/aloe.html ).

Aloe gel is also useful for any dry skin condition, especially
HYPERLINK “http://en.wikipedia.org/wiki/Eczema” \o “Eczema” eczema
around the eyes and sensitive facial skin. and catreating fungal
infections such as ringworm. In HYPERLINK
“http://en.wikipedia.org/wiki/Ayurvedic” \o “Ayurvedic” Ayurvedic
medicine, the gel is usually applied fresh and can even be converted
into an ointment for long-term use.

Internal uses

Aloe contains a number of medicinal substances used as a HYPERLINK
“http://en.wikipedia.org/wiki/Purgative” \o “Purgative” purgative . The
medicinal substance is produced from various species of aloe, such as A.
vera, A. vulgaris, A. socotrina, A. chinensis, and A. perryi. Several
kinds of aloes are commercially available: Barbadoes, Socotrine,
Hepatic, Indian, and Cape aloes. Barbadoes and Socotrine are the
varieties most commonly used for curative purposes.

Aloes is the expressed juice of the leaves of the plant. When the leaves
are cut, the juice that flows out is collected and evaporated. After the
juice has been removed, the leaves are sometimes boiled, to yield an
inferior kind of aloes. The juice of the leaves of certain species, e.g.
Aloe venenosa, is HYPERLINK “http://en.wikipedia.org/wiki/Poison” \o
“Poison” poisonous .

Aloe vera has been widely marketed as having a number of benefits when
taken internally. For example, Aloe has been marketed as a remedy for
coughs, wounds, HYPERLINK “http://en.wikipedia.org/wiki/Ulcer” \o
“Ulcer” ulcers , HYPERLINK “http://en.wikipedia.org/wiki/Gastritis”
\o “Gastritis” gastritis , HYPERLINK
“http://en.wikipedia.org/wiki/Diabetes” \o “Diabetes” diabetes ,
HYPERLINK “http://en.wikipedia.org/wiki/Cancer” \o “Cancer” cancer ,
HYPERLINK “http://en.wikipedia.org/wiki/Headache” \o “Headache”
headaches , HYPERLINK “http://en.wikipedia.org/wiki/Arthritis” \o
“Arthritis” arthritis , HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Immune-system_deficiencies&ac
tion=edit” \o “Immune-system deficiencies” immune-system deficiencies ,
and many other conditions. However, these uses are unproven. The only
substantiated internal use is as a HYPERLINK
“http://en.wikipedia.org/wiki/Laxative” \o “Laxative” laxative .
Furthermore, there is evidence of significant adverse side effects (see
for example HYPERLINK
“http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&do
pt=Abstract&list_uids=15633238” \o
“http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&do
pt=Abstract&list uids=15633238” this paper ). Consult your doctor when
contemplating taking Aloe internally. Avoid use during pregnancy because
the HYPERLINK “http://en.wikipedia.org/wiki/Anthraquinone” \o
“Anthraquinone” anthraquinone HYPERLINK
“http://en.wikipedia.org/wiki/Glycoside” \o “Glycoside” glycosides are
strongly HYPERLINK “http://en.wikipedia.org/wiki/Purgative” \o
“Purgative” purgative . High doses of the leaves can cause vomiting.

Aloe’s benefits include ingesting aloe juice to lower blood sugar levels
in diabetes patients, aloe as a strong laxative, may have some
anti-cancer effects on humans and is even being tested to treat asthma

Compounds in Aloes

Aloe vera contains over seventy-five nutrients and twenty minerals,
nineteen amino acids including all eight essential amino acids and
eleven secondary amino acids as well and twelve vitamins. These vitamins
include: A, B1, B6, B12, C and E ( HYPERLINK
“http://curezone.com/foods/aloevera.html” \o
“http://curezone.com/foods/aloevera.html”
http://curezone.com/foods/aloevera.html ). It has even been referred to
as “a pharmacy in a plant” (Farrar, 2005).

Aloes also contain HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Anthraquinone_gycoside&action
=edit” \o “Anthraquinone gycoside” anthraquinone gycosides ,
HYPERLINK “http://en.wikipedia.org/wiki/Resin” \o “Resin” resins ,
HYPERLINK “http://en.wikipedia.org/wiki/Polysaccharide” \o
“Polysaccharide” polysaccharides , HYPERLINK
“http://en.wikipedia.org/wiki/Sterol” \o “Sterol” sterols , HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Gelonin&action=edit” \o
“Gelonin” gelonins , and HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Chromone&action=edit” \o
“Chromone” chromones . It is also a source of a class of chemicals
called Aloins.

Aloe vera (flowers)

Chemical properties of Aloin

Aloins are soluable and easily extracted by water. Aloes is the
expressed juice of the leaves of the plant. When the leaves are cut, the
juice that flows out is collected and evaporated. After the juice has
been removed, the leaves are sometimes boiled, to yield an inferior kind
of aloes. According to W. A. Shenstone, two classes of Aloins are to be
recognized: (1) HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Nataloin&action=edit” \o
“Nataloin” nataloins , which yield HYPERLINK
“http://en.wikipedia.org/wiki/Picric_acid” \o “Picric acid” picric and
HYPERLINK “http://en.wikipedia.org/wiki/Oxalic_acid” \o “Oxalic acid”
oxalic acids with HYPERLINK
“http://en.wikipedia.org/wiki/Nitric_acid” \o “Nitric acid” nitric acid
, and do not give a red coloration with nitric acid; and (2) HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Barbaloin&action=edit” \o
“Barbaloin” barbaloins , which yield HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloetic_acid&action=edit” \o
“Aloetic acid” aloetic acid (C7H2N3O5), HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Chrysammic_acid&action=edit”
\o “Chrysammic acid” chrysammic acid (C7H2N2O6), picric and oxalic
acids with nitric acid, being reddened by the acid. This second group
may be divided into a-barbaloins, obtained from Barbadoes aloes, and
reddened in the cold, and b-barbaloins, obtained from Socotrine and
Zanzibar aloes, reddened by ordinary nitric acid only when warmed or by
fuming acid in the cold. Nataloin (2C17H13O7·H2O) forms bright yellow
scales. Barbaloin (C17H18O7) forms yellow HYPERLINK
“http://en.wikipedia.org/wiki/Prism_%28geometry%29” \o “Prism
(geometry)” prismatic crystals. Aloes also contain a trace of volatile
oil, to which its odour is due.

Medicinal use of Aloin

The dose is 130-320 mg, that of aloin being 30-130 mg. Aloes can be
absorbed from a broken surface and will then cause purging. When given
internally it increases the actual amount as well as the rate of flow of
the HYPERLINK “http://en.wikipedia.org/wiki/Bile” \o “Bile” bile . It
hardly affects the HYPERLINK
“http://en.wikipedia.org/wiki/Small_intestine” \o “Small intestine”
small intestine , but markedly stimulates the muscular coat of the
HYPERLINK “http://en.wikipedia.org/wiki/Large_intestine” \o “Large
intestine” large intestine , causing purging in about fifteen hours.
There is hardly any increase in the intestinal secretion, the drug being
emphatically not a hydragogue cathartic. There is no doubt that its
habitual use may be a factor in the formation of haemorrhoids; as in the
case of all drugs that act powerfully on the lower part of the
intestine, without simultaneously lowering the venous pressure by
causing increase of secretion from the bowel. Aloes also tends to
increase the menstrual flow and therefore belongs to the group of
emmenagogues. Aloin is preferable to aloes for therapeutic purposes, as
it causes less, if any, pain. It is a valuable drug in many forms of
constipation, as its continual use does not, as a rule, lead to the
necessity of enlarging the dose. Its combined action on the bowel and
the HYPERLINK “http://en.wikipedia.org/wiki/Uterus” \o “Uterus”
uterus is of especial value in chlorosis, of which amenorrhoea is an
almost constant symptom. The drug is obviously contraindicated in
pregnancy and when haemorrhoids are already present. Many well-known
patent medicines consist essentially of aloes.

Lign-aloes and Agarwood

The lign-aloes are quite different from plants of the Aloe genus. The
term “Aloes” is used in the HYPERLINK
“http://en.wikipedia.org/wiki/Bible” \o “Bible” Bible (Numbers 24:6),
but as the trees usually supposed to be meant by this word are not
native in HYPERLINK “http://en.wikipedia.org/wiki/Syria” \o “Syria”
Syria , it has been suggested that the HYPERLINK
“http://en.wikipedia.org/wiki/Septuagint” \o “Septuagint” Septuagint
reading in which the word does not occur is to be preferred. Lign-aloe
is a corruption of the Latin lignum-aloe, a wood, not a resin.
HYPERLINK “http://en.wikipedia.org/wiki/Dioscorides” \o “Dioscorides”
Dioscorides refers to it as agallochon, a wood brought from HYPERLINK
“http://en.wikipedia.org/wiki/Arabia” \o “Arabia” Arabia or
HYPERLINK “http://en.wikipedia.org/wiki/India” \o “India” India , which
was odoriferous but with an astringent and bitter taste. This may be
HYPERLINK “http://en.wikipedia.org/wiki/Agarwood” \o “Agarwood”
Agarwood , a native of East India, HYPERLINK
“http://en.wikipedia.org/wiki/South_East_Asia” \o “South East Asia”
South East Asia , and HYPERLINK “http://en.wikipedia.org/wiki/China”
\o “China” China , which supplies the so-called eagle-wood or
aloes-wood, which contains much resin and oil.

HYPERLINK “http://en.wikipedia.org/wiki/Species” \o “Species” Species

There are around 400 species in the genus Aloe. For a full list, see
HYPERLINK “http://en.wikipedia.org/wiki/List_of_species_of_genus_Aloe”
\o “List of species of genus Aloe” List of species of genus Aloe .
Common species include:

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_angelica&action=edit” \o
“Aloe angelica” Aloe angelica – Wylliespoort Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_arborescens&action=edit”
\o “Aloe arborescens” Aloe arborescens – Candelabra Aloe, Tree Aloe,
Krantz Aloe

Candelabra Aloe (Aloe arborescens)

HYPERLINK “http://en.wikipedia.org/wiki/Aloe_aristata” \o “Aloe
aristata” Aloe aristata – Torch Plant, Lace Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_barberae&action=edit” \o
“Aloe barberae” Aloe barberae – Tree Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_brevifolia&action=edit”
\o “Aloe brevifolia” Aloe brevifolia – Shortleaf Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_castanea&action=edit” \o
“Aloe castanea” Aloe castanea – Cat’s Tail Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_ciliaris&action=edit” \o
“Aloe ciliaris” Aloe ciliaris – Climbing Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_comosa&action=edit” \o
“Aloe comosa” Aloe comosa – Clanwilliam’s Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_dinteri&action=edit” \o
“Aloe dinteri” Aloe dinteri – Namibian Partridge Breast Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_distans&action=edit” \o
“Aloe distans” Aloe distans – Jeweled Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_excelsa&action=edit” \o
“Aloe excelsa” Aloe excelsa – Noble Aloe, Zimbabwe Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_ferox&action=edit” \o
“Aloe ferox” Aloe ferox – Cape Aloe, Tap Aloe, Bitter Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_glauca&action=edit” \o
“Aloe glauca” Aloe glauca – Blue Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_humilis&action=edit” \o
“Aloe humilis” Aloe humilis – Spider Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_khamiensis&action=edit”
\o “Aloe khamiensis” Aloe khamiensis – Namaqua Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_longistyla&action=edit”
\o “Aloe longistyla” Aloe longistyla – Karoo Aloe, Ramenas

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_maculata&action=edit” \o
“Aloe maculata” Aloe maculata – Soap Aloe, Zebra Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_mitriformis&action=edit”
\o “Aloe mitriformis” Aloe mitriformis – Gold Tooth Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_nobilis&action=edit” \o
“Aloe nobilis” Aloe nobilis – Gold Tooth Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_perryi&action=edit” \o
“Aloe perryi” Aloe perryi – Perry’s Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_pictifolia&action=edit”
\o “Aloe pictifolia” Aloe pictifolia – Kouga Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_pillansii&action=edit”
\o “Aloe pillansii” Aloe pillansii – Bastard Quiver Tree

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_plicatilis&action=edit”
\o “Aloe plicatilis” Aloe plicatilis – Fan Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_polyphylla&action=edit”
\o “Aloe polyphylla” Aloe polyphylla – Spiral Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_pratensis&action=edit”
\o “Aloe pratensis” Aloe pratensis – Rosette Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_ramosissima&action=edit”
\o “Aloe ramosissima” Aloe ramosissima – Maidens Quiver Tree

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_saponaria&action=edit”
\o “Aloe saponaria” Aloe saponaria – African Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_speciosa&action=edit” \o
“Aloe speciosa” Aloe speciosa – Tilt-head Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_striata&action=edit” \o
“Aloe striata” Aloe striata – Coral Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_tauri&action=edit” \o
“Aloe tauri” Aloe tauri – Bullocks Bottle Brush Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_variegata&action=edit”
\o “Aloe variegata” Aloe variegata – Partridge-breasted Aloe, Tiger
Aloe

HYPERLINK “http://en.wikipedia.org/wiki/Aloe_vera” \o “Aloe vera”
Aloe vera – True Aloe, Barbados Aloe, Common Aloe, Yellow Aloe,
Medicinal Aloe

HYPERLINK
“http://en.wikipedia.org/w/index.php?title=Aloe_zebrina&action=edit” \o
“Aloe zebrina” Aloe zebrina – Zebra Aloe

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