Aloe vera: Plant of Immortality

Introduction:

The Egyptians called Aloe the “Plant of Immortality” because it can live and even bloom without soil. Aloe has been used medicinally since at least the first century C.E. and continues to be used extensively worldwide.

Synonyms:

Grihakanya, Kanya , Ghritakumari , Vipulasrava , Sthuladala , Dirgha patra , Mandala, Kumari

Biological source:

Dried juice of Aloe ferox Mill, A. perryi Baker, A. vera (L.) N.L. Burm.(= A. barbadensis Mill.)

Botanical name:

Aloe ferox Mill, A. perryi Baker, A. vera (L.) N.L. Burm. (= A. barbadensis Mill.)

Family: Liliaceae

Geographical source:

Aloes is indigenous to eastern and southern Africa and grown in cape colony, Zanzibar and islands of Socotra, also cultivated in Europe and many parts of India including northwest Himalayan region.

Commercial Use:

Distinct parts of the aloe plant and various species are used medicinally. The gel from the fresh leaf is used in a wide range of internal and external applications. The internal use of the gel is regulated as a dietary supplement. The dried latex taken from the bundle sheath cells within the leaf is primarily used as a laxative. It is an official drug in the U.S. Pharmacopeia. Commercially significant species are Aloe ferox Miller (Cape Aloes), A. perryi Baker (Socotrine Aloes) and A. vera (Barbados or Curaçao Aloes). However, many names have been used to describe Aloe, such as A. barbadensis and A. vulgaris. Currently, the correct name is Aloe vera (L.) Burm. f.

In trade, the full botanical name, Aloe vera, is used to refer to gel products. Careful processing of aloe gel is necessary to maintain activity. Aloe is processed using the handfilleted or whole leaf procedure. Hand-filleted processing carefully removes the inner gel while avoiding the yellow sap (latex) found next to the rind. The latex contains aloin, which is removed for internal and external gel products. Whole leaf extracts are made by grinding the entire leaf and then removing the aloin through charcoal filtration at the final stage of processing. The goal of whole leaf processing is to retain as many polysaccharides (complex sugars) as possible, since they have been shown to be partially responsible for aloe’s therapeutic efficacy.

Stabilizing the constituents within aloe is another essential part of developing effective products. The gel must be cool-processed within four hours of harvesting. Tests on some commercial aloe gel products found that processing can decrease the amount of the active ingredients present in the fresh gel .The International Aloe Science Council provides a seal of certification for products that have followed proper processing procedures .The latex sold as the official drug is made from a solid residue processed by draining the liquid from transversely cut aloe leaves.

Botany:

Since Aloe has naturalized throughout the tropics and warm regions worldwide, its true origin is not known. It is suspected to have come from North Africa or the Nile region in Sudan The genus contains at least 324 species of herbs, shrubs, and trees, primarily African, with some in Madagascar and the Arabian Peninsula. Aloe is a perennial, with 15 to 30 fleshy leaves up to 0.5 m long and 8 to 10 cm across at the base. Saw-like teeth mark the margins of the leaves.

History:

Aloe has played a significant medicinal role for thousands of years. Egyptians, Assyrians, and Mediterranean peoples used the dried latex primarily, but also the gel. In Egypt, aloe was called “the plant of immortality” and was given as an offering at the funerals of pharaohs and used in the baths of Egyptian queens Nefertiti and Cleopatra. According to the Roman scholar, Pliny, the plant was also used for embalming. Alexander the Great conquered Socotra Island, reportedly at the request of Aristotle, just to obtain aloe. In the first century C.E., the Greek physician Dioscorides used aloe for mouth infections, sores, wounds and as a purgative. In the10th century, aloe was used in England and during the 17th century, records show that the East India Company frequently purchased aloe from the king of Socotra. Today, Egyptians still hang an aloe plant over the door of a new house to provide a long and fruitful life for its occupants. In India the whole leaves, exudate, and fresh gel aloe are used as a cathartic, stomachic, emmenagogue, and anthelmintic. In China, Mexico, and the West Indies, it has become a common household remedy for a variety of uses. Until the 1930s in the U.S., the primary commercial use of aloe was the dried latex as a laxative.

Modern Use:

In preliminary human clinical studies, the gel has shown significant results in the treatment of asthma, peptic ulcers, and diabetes mellitus. The gel has been sold in the health food market as a tonic, as well as for “supporting the immune system” and “supporting healthy breathing”. Externally, the gel has been used in many ways: cosmetics, dermabrasion, wound-healing, and psoriasis. In cosmetics, the gel is added to moisturizers, cleansers, shampoos, suntan lotions, and sunburn treatments. The drug derived from aloe latex is part of one of the strongest anthraquinone groups that function as stimulant laxatives. The latex is officially approved as a laxative in the U.S., England, and Germany. The German Commission E recommends the use of aloe for occasional constipation and for conditions that require a soft stool, such as anal fissures, hemorrhoids, and after rectal or anal surgery. Externally, the latex is used like the gel and as a soothing agent in treating burns and mild cuts.

Aloe gel has demonstrated wound healing, anti-inflammatory, antiviral, spermicidal, and gastroprotective properties. It has also shown immune-stimulating and cholesterol-lowering activity. Aloe gel is thought to speed recovery from wounds by enhancing the activity of macrophages and fibroblasts. A recent study showed aloe to be more effective than conventional treatments for burns, frostbite, and intra-arterial damage from intravenous drug abuse, as well as tissue injuries from electrical shocks. Aloe gel also helped speed the rate of wound closure and the resistance of the healed wound to tearing. Its wound-healing activity has been partially attributed to the polysaccharide, mannose-6-phosphate . It has been suggested that aloe works as an anti-inflammatory when used topically and when taken orally.

Antiviral activity was shown in an in vitro study using a purified extract from the gel of Aloe barbadensis. The main activity against cytomegalovirus was shown 12-36 hours after infection. An in vitro study using zinc acetate and lyophilized Aloe barbadensis (7.5 and 10 percent) demonstrated an antiviral and spermicidal effect. The authors concluded that it might be useful as a contraceptive, especially significant in preventing the transmission of HIV. Spermicidal activity from Aloe was thought to be due to microelements (boron, barium, calcium, chromium, copper, iron, potassium, magnesium, manganese, phosphorus, and zinc) that immobilize the tails of sperm without causing vaginal irritation. Gastroprotective properties were shown in several animal studies. When aloe gel was administered to rats prior to ulcer-inducing stress, the number of ulcers decreased by 80 percent.

Clinical studies have focused upon the external use of aloe gel for wound healing and psoriasis. In a study that compared aloe to polyethylene oxide gel dressing in the treatment of patients with dermabrasion (surgery to remove tattoos, acne, scars, and wrinkles), aloe accelerated healing by 72 hours. The wounds of patients recovering from burns, frostbite, and intra-arterial drug abuse healed faster, had less tissue loss or morbidity, and fewer complications than those patients treated with conventional methods. Seven percent of the frostbite patients treated with aloe required amputation, compared with 32 percent in the nontreatment group. In another study, aloe also was shown to assist patients recovering from wounds associated with frostbite. One study contradicted these results by showing a delay of 30 days in the healing of wounds on patients treated with aloe gel. A double blind, placebo-controlled study examined the effect of aloe extract (0.5 percent in a hydrophilic cream) for 60 psoriasis vulgaris patients, aged 18 to 50 years. The aloe cream cured 25 out of 30 patients compared to a placebo rate of 2 out of 30. The authors concluded it was a safe alternative treatment for treating psoriasis. The internal use of the gel has been studied for treating asthma, peptic ulcers, and diabetes mellitus. A clinical study found that a fraction of aloe extract enhanced phagocytosis (causing the elimination of bacteria and dust particles) in adult bronchial asthma. Another study examined the effect of aloe on the blood sugar levels of 50 men and 22 women with a diabetic curve on glucose tolerance tests. By week two, cholesterol levels were unchanged, but changes to blood sugar levels and triglyceride levels were statistically significant. A small study of 12 peptic ulcer patients reported positive results from treatment with aloe. The results were attributed to the inhibition of hydrochloric acid secretion, coacervation of pepsin and general detoxification .