The name Aloe comes from the Arabic word alloeh meaning a shining bitter substance. The botanical name of Aloe Vera is Aloe Barbadensis Miller. It belongs to the Liliaceae family, which has about 360 species.
Aloe Vera is a cactus like plant that grows readily in hot and dry climate and currently, because of high demand, is cultivated in large quantities. It grows mainly in dry regions of Asia, Africa, America and Europe. In India, it is found in Maharashtra, Andhra Pradesh, Gujarat, Rajasthan and Tamil Nadu.
Cosmetics and some medicinal products are made from the mucilaginous tissue at the center of the Aloe vera leaf and are called Aloe Vera gel. This gel is a clear, tasteless, thin, jelly like material. The other part of the plant is a group of specialized cells known as the pericyclic tubules. They occur just beneath the outer green rind of the leaf. These cells produce exudates that consist of bitter yellow latex with powerful laxative-like action.
Chemical composition of the plant
Polysaccharides: Aloe gel is 99% of water with a pH of 4.5 and is a common ingredient in many non-prescription skin salves. The gel has an emollient polysaccharide, glucomannan. It is a good moisturizer, and is used in many cosmetics. Other poly saccharides such as arabinan, arabinorhamnogalactan, glactan, galactogalacturan, glucogalactomannan and glucuronic acid containing polysaccharides are isolated from the Aloe vera inner leaf gel.
Anthraquinones /Anthrones: Aloe emodin, aloetic acid, anthranol, aloin A and B, isobarbaloin emodin ester of cinnamic acid are also found in Aloe vera.
Vitamins/ Minerals: It provides vitamin C, A, E, B, B Carotene, Zinc, Calcium, Copper, Magnesium, Manganese and phosphates.
Enzymes: It contains alliase, alkaline phosphatase amylase catalase, lipase peroxidase and corboxy peptidase enzymes.
Plant sterols: plants steroids campestrol, cholesterol, bsitosterol and lupeol.
Medicinal uses of Aloe vera
The Aloe vera exudates are transparent, slippery mucilage or gel given by the thin walled tubular cells in the inner central zone (parenchyma) of the leaf. This mucilage was applied to inflamed skin and during the 20th century, it was helpful for radiation burns.
The bioactive compounds are used as astringent, homeostatic, antidiabetic, antiseptic, antibacterial, antioxidant and anti-tumor agents and also effective in treating stomach ailments, gastrointestinal problems, constipation, radiation injury, wound healing, burns, dysentery, diarrhea and treatment of skin diseases. Currently the plant is widely used in skin care.
Anti-oxidant activity: It contains vitamin A, B Carotene, C and E. They are anti-oxidants. It provides calcium, magnesium, potassium, sodium, and zinc minerals which are essential for the proper functioning of various enzymes which are antioxidants.
Wound healing: Cumulative evidence supports the use of Aloe Vera for the healing of first to second degree burns. The wound healing properties of Aloe Vera gel has been attributed to mannose-6 phosphate. Brady kinase enzymes help in the reduction of excessive inflammation, when applied to the skin topically.
Anti-ulcer activity: A number of glycoproteins present in Aloe vera gel have anti-tumor and anti-ulcer effects.
Anti-bacterial and anti-viral activity: Aloe vera gel provides 12 anthraquinones which are phenolic compounds traditionally known as laxatives. Aloin and Emodin acts as analgesics, antibacterials and antivirals.
Anti-septic and analgesic properties: Aloe vera gel provides some fatty acids like cholesterol, campesterol, B-sisosterol and lupesol. All of them have anti-inflammatory action and lupesol also possess antiseptic and analgesic properties.
Other medicinal uses: Traditionally, Aloe vera gel is used both topically (treatment of wounds, burns, and skin irritations) and internally to treat constipation, ulcers, diabetes,