Aloe, native to East and South Africa, is also known as ‘Lily of the desert’, ‘Plant of immortality’, and ‘The medicine plant’. Aloe barbadensis was introduced to the West Indies at the beginning of the 16th century.
Aloe vera (Aloe barbadensis), is a member of the Liliaceae family and is an evergreen perennial growing to 0.8 m by 1 m at a slow rate. It is in leaf all year and in flower from May to June. The flowers are hermaphroditic (having both male and female organs).
The plant prefers sandy or medium loamy, well-drained soil and can grow in nutritionally poor soil. It cannot grow in shade. It can grow in dry or moist soil and can tolerate drought. In gardens the plant needs some protection from winter cold.
Seeds are usually sown during the spring season in a greenhouse. Seeds usually germinate in 1-6 months at 25° C. One should place the seedlings in individual pots of very well drained soil when they are large enough to handle and grow them in a sunny part of the greenhouse for at least the first two winters. If the plants are to be planted outdoors, they should be planted in early summer to allow them to become established before the winter and to give them some protection from the cold. The plants produce offsets quite freely and they can be divided at any time of the year as long as long as it is warm enough to encourage fresh root growth to allow re-establishment of the plants.
Aloe vera leaf contains major glycoside-anthracene derivatives such as hydroxy anthraquinone derivatives (25-40) namely, aloin, barbaloin (a mixture of aloin A & B), the diastereoisomeric 10-C glucosides of aloe-emodin anthrone and 7-hydroxyaloin isomers. Minor components also include aloe emodin, chrysophanol, chromone derivatives, namely, aloeresin B (=aloesin, up to 30%) with its p-coumaryl derivatives aloeresins A & C and the aglycone aloesone. The active component of aloe is a mixture of glycosides called aloin. The proportion of aloin varies in different specimens of aloes. The chief constituent of aloin is barbaloin, which is a pale yellow crystalline glycoside, soluble in water.
Uses for Aloe vera 
Aloe vera is a fairly well known herbal preparation with a long history of use. It is widely used in modern herbal practice and is often available in proprietary herbal preparations. It has two distinct types of medicinal uses:
1) The clear gel contained within the leaf makes an excellent treatment for wounds, burns and other skin disorders by placing a protective coat over the affected area, speeding up the rate of healing and reducing the risk of infection. This action is in part due to the presence of Aloectin B, which stimulates the immune system. To obtain this gel, the leaves can be cut in half along their length and the inner pulp rubbed over the affected area of skin. This has an immediate soothing effect on all sorts of burns and other skin problems.
2) The second use comes from the yellow sap at the base of the leaf. The leaves are cut transversally at their base and the liquid that exudes from this cut is dried. It is called bitter aloes and contains anthraquinones which are a useful digestive stimulant and a strong laxative.
The plant is useful as a emmenagogue, emollient, laxative, purgative, stimulant, stomachic, tonic, vermifuge and vulnerary. Extracts of the plant have antibacterial activity.
Apart from its external use on the skin, Aloe vera (usually the bitter aloes) is also taken internally in the treatment of chronic constipation, poor appetite, digestive problems etc.
Aloe vera should not be given to pregnant women or people with hemorrhoids or irritable bowel syndrome. The plant is strongly purgative so great care should be taken to adjust the dosage properly. The plant is used to test if there is blood in the feces. This plant has a folk history of treatment in cases of cancer. Other uses include cosmetic products employing leaf extracts of aloe.
Plants have been grown indoors in pots in order to help remove toxins from the atmosphere. The plant is unusual in that it continues to release oxygen and absorb carbon dioxide in the dark, making it very suitable for growing in living rooms.
The cathartic action of the Aloe vera is attributed to the anthraquinone glycosides, chiefly aloin.
Commercial preparations of creams, lotions, shampoos and allied products such as gel of aloe are used as it has a cooling effect and acts as a moisturizing agent.
Given the above-described useful properties of aloe, there is a large demand for the aloe plants. The present invention helps to satisfy this demand by providing a means for in vitro micropropagation of Aloe vera which is economical and can produce on a commercial scale true-to-type elite variety, disease-free Aloe vera plants of uniform quality.
Aloe vera Plant Tissue Culture
Micropropagation is the in vitro regeneration of plants from organs, tissues, cells or protoplast using techniques like tissue culture for developing true-to-type resultant plants of a selected genotype. In general, tissue from a plant commonly known as an explant is isolated from a plant whose multiplication is desired to create a sterile tissue culture of that species in vitro. From explants a culture is initiated. Once a culture is stabilized and growing well in vitro, multiplication of the tissue or regeneration of entire plant can be carried out. Shoots (tips, nodes or internodes) and leaf pieces are commonly used but cultures can be generated from many different tissues. Juvenile tissues generally respond best. Besides the source of the explants, the chemical composition of the culture medium and the physical environment of cultures have been found to be of a great influence on the regeneration capacity, multiplication ratio, growth and development of new plants in the culture system. Therefore, one needs to optimize these factors for individual plant species.
Plant tissue culture is rapidly becoming a commercial method for large-scale propagation of the elite varieties, particularly for plants which are difficult to propagate rapidly by conventional methods. Tissue culture is particularly useful for multiplication of plants which are slow-growing (turmeric, ginger, cardamom); cross-pollinated (coconut, teak, eucalyptus, cashew, mango and those which show wide variation in the progeny), male sterile lines (cotton, sorghum, pearl millet); and newly free plants by meristem culture (sugarcane, potatoes, tapioca, etc).
There is a need in the art for micropropagation methods for aloe that have high shoot ratios (for example, each plant gives 4 plants after 4 weeks i.e., 1:4 multi rate) and high survival rates up to the hardening stage.