|Posted by Maddalena Frau on September 17, 2012 at 12:20 AM|
Aloe vera is a stemless or very short-stemmed succulent plant growing to 60–100 cm (24–39 in) tall, spreading by offsets. The leaves are thick and fleshy, green to grey-green, with some varieties showing white flecks on the upper and lower stem surfaces. The margin of the leaf is serrated and has small white teeth. The flowers are produced in summer on a spike up to 90 cm (35 in) tall, each flower being pendulous, with a yellow tubular corolla 2–3 cm (0.8–1.2 in) long. Like other Aloe species, Aloe vera forms arbuscular mycorrhiza, a symbiosis that allows the plant better access to mineral nutrients in soil.
Aloe vera has a long association with herbal medicine, although it is not known when its medical applications were first suspected. Early records of Aloe vera use appear in the Ebers Papyrus from 16th century BC, in both Dioscorides' De Materia Medica and Pliny the Elder's Natural History written in the mid-first century CE along with the Juliana Anicia Codex produced in 512 AD. The species is used widely in the traditional herbal medicine of China, Japan, Russia, Africa, the United States, Jamaica, Latin America and India, although at certain doses, it has toxic properties when used either for ingested or topical applications.
Aloin, a compound found in the exudate of some Aloe species, was the common ingredient in over-the-counter (OTC) laxative products in the United States.
But Aloe vera is an indispensable part of your herbal dispensary. The leaf juices of the aloe plant have important medicinal uses making aloe one of the most respected medicinal plants found in many gels, creams and lotions. Modern researchers have identified several reasons why aloe gel spurs wound healing: It has antibacterial, antifungal and antiviral compounds that help prevent wound infections. It also has immune-stimulating and anti-inflammatory compounds, and it stimulates collagen synthesis and skin regeneration after a burn. Aloe gel contains vitamins C and E, plus the mineral zinc. Aloe vera gel is soothing, anti-inflammatory, and antibacterial - helps heal acne, improve the appearance of wrinkles, and hydrate damaged skin. Applying a thin layer of aloe vera gel will help ease discomfort caused by painful skin irritations, flea and insect bites.
Commodities Aloe vera is now widely used on facial tissues, where it is promoted as a moisturiser and/or anti-irritant to reduce chafing of the nose of users suffering hay-fever or cold. It is common practice for cosmetic companies to add sap or other derivatives from Aloe vera to products such as makeup, tissues, moisturizers, soaps, sunscreens, incense, shaving cream, and shampoos. Other uses for extracts of aloe vera include the dilution of semen for the artificial fertilization of sheep, use as fresh food preservative, and use in water conservation in small farms. It has also been suggested that biofuels could be obtained from Aloe vera seeds. Aloe is also used as a food substance. Some molecular gastronomists have begun to take advantage of its gelling properties. Perhaps the most notable among these is Chef Quique Dacosta's "Oysters Guggenheim," created at El Poblet in Spain.
Research for medical uses
Wound & Lesion Treatment Aloe vera may be effective in treatment of wounds. Topical application of aloe vera may also be effective for genital herpes and psoriasis. However, it is not effective for the prevention of radiation-induced injuries. Gels from Aloe vera have been compared to those derived from other aloe species and with other plants belonging to the family Asphodelaceae.
Bulbine frutescens, for example, is used widely for burns and a host of skin afflictions Aloe vera extracts have antibacterial and antifungal activities, which possibly could help treat skin infections, such as boils and benign skin cysts and may inhibit growth of fungi causing tinea. For bacteria, inner-leaf gel from aloe vera was shown in one study to inhibit growth of Streptococcus and Shigella species in vitro. In contrast, aloe vera extracts failed to show antibiotic properties against Xanthomonas species.
However, the plant polysaccharides present in Aloe vera, although offering no direct protection against sunburn, may offer skin protection by specifically targeting pathways activated by UV radiation that can lead to non-melanoma skin cancer.
UV radiation causes local depletion of antigen-presenting Langerhans cell (LCs), as well as systemic immunosuppression. In experiments in laboratory mice, polysaccharides preserved the number and morphology of immunosuppresive LCs and dendritic cells (DCs) in skin that was damaged by UV. These saccharides have also been seen to preserve delayed-type hypersensitivity and cutaneous contact hypersensitivity suppressed by acute UV radiation. Delayed-type hypersensitivity-protective saccharides extracted from A. vera also prevented the systemic suppression of T-cell-mediated immune responses and the production of keratinocyte-derived Interleukin 10 by UV-irradiated epidermal cells in mice.
Compounds extracted from aloe vera have been used as an immunostimulant that aids in fighting cancers in cats and dogs; however, this treatment has not been scientifically tested in humans.
Dental care, in a double-blind clinical trial, both the group using an aloe vera containing dentifrice and the group using a fluoridated dentifrice had a reduction of gingivitis and plaque, but no statistically significant difference was found between the two.
Diabetes and blood lipidsThere is preliminary evidence that A. vera extracts may be useful in the treatment of diabetes and elevated blood lipids in humans.These positive effects are thought to be due to the presence of compounds such as mannans, anthraquinones and lectins.
Internal intake of aloe vera has been linked in preliminary research with improved blood glucose levels in diabetics. It has also been linked with lower blood lipids in hyperlipidaemic patients, but also with acute hepatitis (liver disease).
Other preliminary studies have suggested oral aloe vera gel reduce symptoms and inflammation in patients with ulcerative colitis.
Toxicity Ingestion of Aloe vera is associated with diarrhea, electrolyte imbalance, kidney dysfunction, and conventional drug interactions; episodes of contact dermatitis, erythema, and phototoxicity have been reported from topical applications. Diarrhea, caused by the laxative effect of oral aloe vera, can decrease the absorption of many drugs.