aloe

1. Any of various chiefly African plants of the genus Aloe, having rosettes of succulent, often spiny-margined leaves and long stalks bearing yellow, orange, or red tubular flowers.
2. See aloe vera.
3. aloes (used with a sing. verb) A laxative drug obtained from the processed juice of a certain species of aloe. Also called bitter aloes.

[Middle English, from Old English aluwe, from Latin aloē, from Greek.]

For more information on aloe, visit Britannica.com.

Description

Appearance

Aloe vera, a member of the lily family, is a spiky, succulent, perennial plant. It is indigenous to eastern and southern Africa, but has been spread throughout many of the warmer regions of the world, and is also popularly grown indoors. There are about 300 identified species, but Aloe vera ("true aloe") is the most popular for medical applications. It has also been known as Aloe vulgaris ("common aloe") and Aloe barbadensis. The plant has yellow flowers and triangular, fleshy leaves with serrated edges that arise from a central base and may grow to nearly 2 ft (0.6 m) long. Each leaf is composed of three layers. A clear gel, that is the part of the plant used for topical application is contained within the cells of the generous inner portion. Anthraquinones, which exert a marked laxative effect, are contained in the bitter yellow sap of the middle leaf layer. The fibrous outer part of the leaf serves a protective function.

History

Aloe vera has been in use for thousands of years, and is mentioned in records as long ago as 1750 B.C. Use of the plant is thought to have originated in Egypt or the Middle East. It was reputedly used in Egyptian embalming procedures, as drawings of Aloe vera have been found on cave walls in the region. Legend has it that Aloe vera was one of Cleopatra's secrets for keeping her skin soft. Pliny and Dioscorides of ancient Greece wrote of the healing effects of this plant. Additionally, Alexander the Great is said to have acquired Madagascar so that he could utilize the Aloe vera growing there to treat soldiers' wounds. It is also a remedy which has long been used in the Indian practice of Ayurvedic medicine.

In the United States, Aloe vera was in use by the early 1800s, but primarily as a laxative. A turning point occurred in the mid-1930s, when a woman with chronic and severe dermatitis resulting from x-ray treatments was healed by an application of Aloe vera leaf gel. Success with this patient encouraged trials with others suffering from radiation burns. Evidence of the effectiveness remained anecdotal until 1953, when Lushbaugh and Hale produced a convincing study, using Aloe vera to treat beta radiation lesions in rats. Other experimental protocols have been carried out using animals since that time, but there is little human research data to describe the degree of effectiveness of Aloe vera treatment. Some evidence suggests that it is especially helpful in the elderly and other people with impaired health or failing immune systems.

Biologic Components

Aloe vera contains a wealth of substances that are biologically active. The laxative, and in large doses, purgative, effects of Aloe vera latex are attributable to a group of chemicals known as the anthraquinones. Aloin, barbaloin, and aloe-emodin, and aloectic acid, are a few of the anthraquinones contained in the latex layer. The latest, and perhaps most exciting component discovered in Aloe vera is a biologically active polysaccharide known as acetylated mannose, or acemannan. This substance has been shown to be a highly effective immune stimulant, with activity against the viruses causing the flu, measles, and early stages of AIDS. It has been used effectively against some veterinary cancers, most notably sarcoma, and is being investigated as an agent to be used to treat cancer in humans. Acemannan is one of many saccharides contained in Aloe vera. Some of the others are arabinose, cellulose, galactose, mannose, and xylose. Prostaglandins are a third important set of compounds, and are thought to play a major role in wound healing. Aloe vera also contains fatty acids, enzymes, amino acids, vitamins, minerals, and other substances. The interaction of all these components produces a favorable environment for wound healing.

General Use

Few botanicals are as well known or as highly thought of as the Aloe vera plant. Throughout recorded history, it has been used to keep skin beautiful and restore it to health. A frequent moisturizing ingredient in cosmetics and hair care products, it also promotes the healing of burns and superficial wounds, but should not be used on deep or surgical wounds of punctures. Topical application has been successful in treatment of sunburn, frostbite, radiation injuries, some types of dermatitis, psoriasis, cuts, insect stings, poison ivy, ulcerations, abrasions, and other dermatologic problems. Healing is promoted by the anti-inflammatory components, including several glycoproteins and salicylates, and substances that stimulate growth of skin and connective tissue. Aloe vera contains a number of vitamins and minerals that are necessary to healing, including vitamin C, vitamin E, and zinc. It also exerts antifungal and antibacterial effects, and thus helps to prevent wound infections. One study showed it to have a little more activity than the antiseptic silver sulfadiazine against a number of common bacteria that can infect the skin. It has moisturizing and pain relieving properties for the skin lesions, in addition to healing effects.

Aloe vera gel products may also be used internally. They should not contain the laxative chemicals found in the latex layer. There is some evidence that Aloe vera juice has a beneficial effect on peptic ulcers, perhaps inhibiting the causative bacteria, Helicobacter pylori. It appears to have a soothing effect on the ulcer, and interferes with the release of hydrochloric acid by the stomach. Colitis and other conditions of the intestinal tract may also respond favorably to the internal use of gel products. Aloe vera has been shown to exert a stabilizing effect on blood sugar in studies done on mice, indicating a possible place for it in the treatment of diabetes. One study suggested that giving Aloe vera extract orally to patients with asthma who are not dependent on steroids could improve symptoms. A health care provider should be consulted about these uses. Other suggested, but insufficiently proven, indications for oral Aloe vera gel include prevention of kidney stones and relief of arthritis pain.

Aloe vera products derived from the latex layer are taken orally for the laxative effect. They can cause painful contractions of the bowel if taken in high doses. Milder measures are recommended first.

The concentration of the immune stimulant acemannan is variable in the natural plant, as well as gel and juice products, but it is also available in a purified, standardized, pharmaceutical grade form. An injectable type is used in veterinary medicine to treat fibrosarcoma and feline leukemia, a condition caused by a virus in the same family as AIDS.

Preparations

Commercial Products

Choosing effective Aloe vera products can be challenging. Once a leaf is cut, enzymes start to break down some of the long chain sugars which make Aloe vera gel an effective healing product, so it is important for the plant to have been properly handled and stabilized. Ask for help in selecting a reputable company to buy from. When shopping for a product to use for topical healing, look for Aloe vera to be one of the first products listed to ensure that it is not too dilute to be efficacious. Commercial, stabilized gel products may not work as well as the fresh gel, but cold processing is thought to best retain the beneficial properties. The FDA does not regulate labeling of Aloe vera products.

Aloe vera juice is most often the form of the gel that is used internally. At least half of the juice should be Aloe vera gel. If laxative properties are not desired, be sure that the juice does not contain latex. A product that is made from the whole leaf does not necessarily contain anthraquinones from the latex layer, as those are water-soluble and can be separated out during processing. Capsules and tinctures of the gel are also available. Oral forms of the latex extract are generally capsules, as it is extremely bitter.

Growing Aloe At Home

For common topical use, keeping an Aloe vera plant at home is one of the easiest ways to get the freshest and most concentrated gel. It is easy to cultivate, requiring only good drainage, mild temperatures, and occasional watering. Bring the plant inside if outside temperatures are less than 40°F (4.4°C). It will tolerate either full or partial sunlight, but will require more frequent watering in full sun. Water it only when the soil has become dry. To use the gel, break off a leaf and cut it lengthwise to expose the inner layer. Scoop the gel out and apply generously to the area needing treatment. Discard whatever gel is not used immediately, as it will degenerate quickly. The inner portion of the leaf may also be applied directly to a skin injury, and bound to it.

Precautions

Aloe vera gel is generally safe for topical use, but it is best to apply it to a small area first to test for possible allergic reaction. Stinging and generalized dermatitis may result in individuals who are sensitive to it. The vast majority of the warnings apply only to products containing anthraquinones, such as aloin and barbaloin (as well as the numerous others), which are found in the latex layer of the plant. Aloe vera latex should not be used internally by women who are pregnant or lactating, or by children. This product can cause abortion or stimulate menstruation. It may pass into the milk of breastfeeding mothers. People who have abnormal kidney function, heart disease, or gastrointestinal diseases are best advised to avoid any product containing Aloe vera latex or anthraquinones. Prolonged, internal use in high doses may produce tolerance so that more is required to obtain the laxative effect. Be aware of the possibility that any Aloe vera product for internal use that is supposed to contain only the gel portion can become contaminated by the anthraquinones of the latex layer. For this reason, people who have a contraindication for using Aloe vera latex should use caution when taking an Aloe vera gel product internally.

Side Effects

Internal use of Aloe vera latex may turn the urine red, and may also cause abdominal pain or cramps when products containing anthraquinones are consumed.

Interactions

Chronic internal use of products containing Aloe vera latex may increase the likelihood of potassium loss when used concomitantly with diuretics or corticosteroids. It may possibly compound the risk of toxicity when used with cardiac glycosides (both prescription and herbal types) and antiarrhythmic drugs. Absorption of other oral medications can be decreased. Aloe vera latex should not be used with other laxative herbs, which may also lead to excessive potassium loss.

Internal use of Aloe vera gel can cause changes in blood sugar, so diabetics should monitor blood glucose levels during use, particularly if insulin or other pharmaceuticals are being used to control hyperglycemia.

Topical Aloe vera may enhance the effect of topical corticosteroids and allow a reduction in the amount of the steroid being used.

Resources

Books

Bratman, Steven and David Kroll. Natural Health Bible. Prima Health, 1999.

Chevallier, Andrew. The Encyclopedia of Medicinal Plants. DK Publishing Inc., 1996.

Jellin, J. M., F. Batz, and K. Hitchens. Pharmacist's Letter/Prescriber's Letter Natural Medicines Comprehensive Database. Therapeutic Research Faculty, 1999.

Murray, Michael T. The Healing Power of Herbs. Prima Health, 1995.

[Article by: Judith Turner]

The dried juice of plants of the genus Aloe of the Liliaceae family. It is an anthraquinone cathartic and was at one time the favored purgative for horses. Called also aloes. The name aloe is also used to refer to the fragrant wood of the tree Aquilaria agallocha.

• a. vera — a mucinous substance obtained from the leaves of the plant, Aloe vera. Various therapeutic properties are claimed, including antibacterial, antifungal and anti-inflammatory activity. It is often used on burns.

Tutor's tip: If your friends "allow" (permit) you to use their "aloe" (plant whose juice is used medicinally), you'll feel better soon. To go "alow" is a nautical term that means below the deck.

Aloe.
Aloe succotrina
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Asparagales
Family:	Asphodelaceae
Genus:	Aloe L.
Species
See Species

For other uses, see Aloe (disambiguation).

Aloe, also written Aloë, is a genus containing about four hundred species of flowering succulent plants. The most common and well known of these is Aloe vera, or "true aloe".

The genus is native to Africa, and is common in South Africa's Cape Province, the mountains of tropical Africa, and neighbouring areas such as Madagascar, the Arabian peninsula, and the islands off Africa.

The APG II system (2003) placed the genus in the family Asphodelaceae. In the past it has also been assigned to families Aloaceae and Liliaceae or lilly family. Members of the closely allied genera Gasteria, Haworthia and Kniphofia, which have a similar mode of growth, are also popularly known as aloes. Note that the plant sometimes called American aloe (Agave americana) belongs to Agavaceae, a different family.

Most Aloe species have a rosette of large, thick, fleshy leaves. The leaves are often lance-shaped with a sharp apex and a spiny margin. Aloe flowers are tubular, frequently yellow, pink or red and are borne on densely clustered, simple or branched leafless stems.

Many species of Aloe appear to be stemless, with the rosette growing directly at ground level; other varieties may have a branched or unbranched stem from which the fleshy leaves spring. They vary in colour from grey to bright-green and are sometimes striped or mottled. Some Aloes native to South Africa are arborescent. ^[1]

Contents 1 Uses 1.1 Historical uses 2 Aloin in OTC laxative products 2.1 Chemical properties 3 Popular culture 4 Species 5 Trivia 6 See also 7 References 8 External links 9 Images

Uses

This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (February 2007)

Aloe species are frequently cultivated as ornamental plants both in gardens and in pots. Many Aloe species are highly decorative and are valued by collectors of succulents. Aloe vera is used both internally and externally on humans, and is claimed to have some medicinal effects, which have been supported by scientific and medical research.

Historical uses

Historical use of various Aloe species by humans is well documented. Documentation of the clinical effectiveness is available, although relatively limited.^[2]

Of the 300 species of Aloe, only a few were used traditionally as a herbal medicine, aloe vera again being the most commonly used version of aloe in herbal medicine. Also included are Aloe perryi (found in northeastern Africa) and Aloe ferox (found in South Africa). The Greeks and Romans used aloe vera to treat wounds. In the Middle Ages, the yellowish liquid found inside the leaves was favored as a purgative.^{[citation needed]} It should be noted that processed aloe that contains aloin is generally used as a laxative, whereas processed aloe vera juice that does not contain significant aloin is used for digestive healing.

Some species, particularly Aloe vera are used in alternative medicine and in the home first aids. Both the translucent inner pulp and the resinous yellow aloin from wounding the Aloe plant are used externally to relieve skin discomforts. As an herbal medicine, aloe vera juice is commonly used internally to relieve digestive discomfort "aloe for heartburn". http://findarticles.com/p/articles/mi_m0FKA/is_4_69/ai_n18791510.  "aloe alt med". http://altmedicine.about.com/od/therapiesfrometol/a/heartburn.htm.  "Aloe IBS study". http://www.medscape.com/viewarticle/546327. . Some modern research suggests Aloe vera can significantly slow wound healing compared to normal protocols of treatment.^[3] Other reviews of randomised and controlled clinical trials have provided no evidence that Aloe vera has a strong medicinal effect.^[4][5]

Today, aloe vera is used both internally and externally on humans. The gel found in the leaves is used for soothing minor burns, wounds, and various skin conditions like eczema and ringworm. The extracted aloe vera juice aloe vera plant is used internally to treat a variety of digestive conditions. The use of this herbal medicine was popularized in the 1950s in many Western countries. The gel's effect is nearly immediate; it also applies a layer over wounds that is said to reduce the chance of any infection.^[3]

There have been relatively few studies about possible benefits of Aloe gel taken internally, yet it has been found to be anti-carcinogenic.^{[citation needed]} Data also suggest that components of Aloe inhibit tumor growth.^[6] There have been some studies in animal models which indicate that extracts of Aloe have a significant anti-hyperglycemic effect, and may be useful in treating Type II diabetes. These studies have not been confirmed in humans.^[7]

Aloin in OTC laxative products

On May 9, 2002, the U.S. Food and Drug Administration issued a final rule banning the use of aloin, the yellow sap of the aloe plant for use as laxative ingredient in over-the-counter drug products.^[8] Most aloe juices today do not contain significant aloin.

Chemical properties

Succulent plants, such as this Aloe, store water in their enlarged fleshy leaves, stems, or roots, as shown in this split aloe leaf. This allows them to survive in arid environments.

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 Barbados Aloe, and reddened in the cold, and b-barbaloins, obtained from Socotrine and Zanzibar Aloe, reddened by ordinary nitric acid only when warmed or by fuming acid in the cold. Nataloin (2C₁₇H₁₃O₇·H₂O) forms bright yellow scales. Barbaloin (C₁₇H₁₈O₇) prismatic crystals. Aloe species also contain a trace of volatile oil, to which its odour is due.^{[citation needed]}

Popular culture

Aloe vossii

Aloe rubrolutea occurs as a charge in heraldry, such as in the Civic Heraldry of Namibia.^[9]

Species

There are around 400 species in the genus Aloe. For a full list, see List of species of genus Aloe. Species include:

• Aloe vera - used in healthcare & health products
• Aloe arborescens - used in healthcare
• Aloe aristata - Torch Plant, Lace Aloe
• Aloe dichotoma - quiver tree or kokerboom
• Aloe nyeriensis
• Aloe variegata - Partridge-breasted Aloe, Tiger Aloe
• Aloe barbadensis - Barbados Aloe, Common Aloe, Yellow Aloe, Medicinal Aloe. This is an older name for Aloe vera.
• Aloe wildii

Trivia

Aloe tree on Batum stamp, 1919.

An Aloe tree appeared on stamps issued in 1919 by Batum, a semi-autonomous region of Georgia in the South Caucasus region.

See also

• List of Aloe species
• List of Southern African indigenous trees

References

1. ^ Images of aloe trees.
2. ^ Reynolds, T (ed) Aloes: The genus Aloe. CRC Press. ISBN 978-0415306720
3. ^ ^{a b} Schmidt JM, Greenspoon JS (1991). "Aloe vera dermal wound gel is associated with a delay in wound healing". Obstet Gynecol 78 (1): 115–7. PMID 2047051. 
4. ^ Richardson J, Smith JE, McIntyre M, Thomas R, Pilkington K (2005). "Aloe vera for preventing radiation-induced skin reactions: a systematic literature review". Clin Oncol (R Coll Radiol) 17 (6): 478–84. PMID 16149293. 
5. ^ Ernst E, Pittler MH, Stevinson C (2002). "Complementary/alternative medicine in dermatology: evidence-assessed efficacy of two diseases and two treatments". Am J Clin Dermatol 3 (5): 341–8. doi:10.2165/00128071-200203050-00006. PMID 12069640. 
6. ^ Cosmetic Ingredient Review Expert, Panel (2007). "Final report on the safety assessment of Aloe andongensis extract, Aloe andongensis leaf juice, Aloe arborescens leaf extract, Aloe arborescens leaf juice, Aloe arborescens leaf protoplasts, Aloe barbadensis flower extract, Aloe barbadensis leaf, Aloe barbadensis leaf extract, Aloe barbadensis leaf juice, Aloe barbadensis leaf polysaccharides, Aloe barbadensis leaf water, Aloe ferox leaf extract, Aloe ferox leaf juice, and Aloe ferox leaf juice extract". Int. J. Toxicol. 26 Suppl 2: 1–50. doi:10.1080/10915810701351186. PMID 17613130. 
7. ^ Tanaka M, Misawa E, Ito Y, Habara N, Nomaguchi K, Yamada M, Toida T, Hayasawa H, Takase M, Inagaki M, Higuchi R (2006). "Identification of five phytosterols from Aloe vera gel as anti-diabetic compounds". Biol. Pharm. Bull.=) 29 (7): 1418–22. doi:10.1248/bpb.29.1418. PMID 16819181. 
8. ^ Food And Drug Administration,, HHS (2002). "Status of certain additional over-the-counter drug category II and III active ingredients. Final rule". Fed Regist 67 (90): 31125–7. PMID 12001972. 
9. ^ "NAMIBIA - WINDHOEK". http://www.ngw.nl/int/afr/windhoek.htm. Retrieved 2008-01-24. 

External links

Wikimedia Commons has media related to: Aloe

Images

Aloe arborescens	Aloe aristata	Aloe dichotoma	Aloe hereroensis
Aloe parvula	Aloe peglerae	Aloe maculata (A. saponaria)	Aloe maculata flower
Aloe sophie	Aloe speciosa	Aloe striatula	Aloe rauhii

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
n. - aloesaft, aloe

Nederlands (Dutch)
aloë(sap)

Français (French)
n. - aloès

Deutsch (German)
n. - (bot.) Aloe

Ελληνική (Greek)
n. - (φυτολ.) αλόη

Italiano (Italian)
aloe

Português (Portuguese)
n. - aloés, áloe (m) (f) (Bot.)

Русский (Russian)
алоэ, сок алоэ, применяемый в медицине

Español (Spanish)
n. - áloe, lináloe, acíbar, zabila

Svenska (Swedish)
n. - aloe

中文（简体）(Chinese (Simplified))
芦荟, 芦荟油

中文（繁體）(Chinese (Traditional))
n. - 蘆薈, 蘆薈油

한국어 (Korean)
n. - 노회(백합과의 식물), 침향

日本語 (Japanese)
n. - アロエ, アロエ汁

العربيه (Arabic)
‏(الاسم) نبات الصبر : ينبت في افريقيا تستخرج منه عصاره تستخدم في الطب‏

עברית (Hebrew)
n. - ‮אלווי (צמח-נוי)‬

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