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Aloe - Реферат

substantiated internal use is as a laxative. Furthermore, there is evidence of significant adverse side effects (see for example this paper). Consult your doctor when contemplating taking Aloe internally. Avoid use during pregnancy because the anthraquinone glycosides are strongly 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 (http://curezone.com/foods/aloevera.html). It has even been referred to as "a pharmacy in a plant" (Farrar, 2005).
Aloes also contain anthraquinone gycosides, resins, polysaccharides, sterols, gelonins, andchromones. 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) nataloins, which yield picric and oxalic acids with nitric acid, and do not give a red coloration with nitric acid; and (2) barbaloins, which yield aloetic acid (C7H2N3O5), 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 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 bile. It hardly affects the small intestine, but markedly stimulates the muscular coat of the 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 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 Bible (Numbers 24:6), but as the trees usually supposed to be meant by this word are not native in Syria, it has been suggested that the 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. Dioscorides refers to it as agallochon, a wood brought from Arabia or India, which was odoriferous but with an astringent and bitter taste. This may be Agarwood, a native of East India, South East Asia, and China, which supplies the so-called eagle-wood or aloes-wood, which contains much resin and oil.
There are around 400 species in the genus Aloe. For a full list, see List of species of genus Aloe. Common species include:
" Aloe angelica - Wylliespoort Aloe
" Aloe arborescens - Candelabra Aloe, Tree Aloe, Krantz Aloe
Candelabra Aloe (Aloe arborescens)
" Aloe aristata - Torch Plant, Lace Aloe
" Aloe barberae - Tree Aloe
" Aloe brevifolia - Shortleaf Aloe
" Aloe castanea - Cat's Tail Aloe
" Aloe ciliaris - Climbing Aloe
" Aloe comosa - Clanwilliam's Aloe
" Aloe dinteri - Namibian Partridge Breast Aloe
" Aloe distans - Jeweled Aloe
" Aloe excelsa - Noble Aloe, Zimbabwe Aloe
" Aloe ferox - Cape Aloe, Tap Aloe, Bitter Aloe
" Aloe glauca - Blue Aloe
" Aloe humilis - Spider Aloe
" Aloe khamiensis - Namaqua Aloe
" Aloe longistyla - Karoo Aloe, Ramenas
" Aloe maculata - Soap Aloe, Zebra Aloe
" Aloe mitriformis - Gold Tooth Aloe
" Aloe nobilis - Gold Tooth Aloe
" Aloe perryi - Perry's Aloe
" Aloe pictifolia - Kouga Aloe
" Aloe pillansii - Bastard Quiver Tree
" Aloe plicatilis - Fan Aloe
" Aloe polyphylla - Spiral Aloe
" Aloe pratensis - Rosette Aloe
" Aloe ramosissima - Maidens Quiver Tree
" Aloe saponaria - African Aloe
" Aloe speciosa - Tilt-head Aloe
" Aloe striata - Coral Aloe
" Aloe tauri - Bullocks Bottle Brush Aloe
" Aloe variegata - Partridge-breasted Aloe, Tiger Aloe
" Aloe vera - True Aloe, Barbados Aloe, Common Aloe, Yellow Aloe, Medicinal Aloe
" Aloe zebrina - Zebra Aloe