Aloe vera is a plant that has been used for medicinal purposes for centuries. It is composed of three layers: an inner clear gel that contains 99% water and rest is made of glucomannans, amino acids, lipids, sterols, and vitamins; an exudate which consists of yellow sap and colorless mucus; and an outer thick layer of 15–20 cells called as rind which has protective function and synthesizes carbohydrates and proteins. Aloe vera contains approximately 110 potentially active constituents from six different classes: chromone and its glycoside derivatives; anthraquinone and its glycoside derivatives; flavonoids; phenylpropanoids and coumarins; phenylpyrone and phenol derivatives; and phytosterols and others. Some of the key ingredients or materials found in aloe vera include:
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Polysaccharides: Aloe-gel is composed of approximately 55% polysaccharides, namely acemannan and glucomannan, that contain several bioactive components applicable as edible coatings. The characteristics include transparent, thick, slimy.
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Vitamins: Aloe vera contains vitamins such as vitamin A, C, and E.
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Enzymes: Aloe vera contains enzymes such as amylase and lipase, which can aid in digestion.
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Minerals: Aloe vera contains minerals such as calcium, magnesium, and potassium.
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Anthraquinones: Aloe vera provides 12 anthraquinones, which are phenolic compounds traditionally known as laxatives. Aloin and emodin act as analgesics, antibacterials, and antivirals.
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Salicylic acid: Aloe vera contains salicylic acid, which has an inhibitory action on fungi, bacteria, and viruses.
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Lupeol: Aloe vera contains lupeol, which has an inhibitory action on fungi, bacteria, and viruses.
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Sulfur: Aloe vera contains sulfur, which has an inhibitory action on fungi, bacteria, and viruses.
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Tocopheryl Acetate: Aloe vera contains tocopheryl acetate, which is an antioxidant.
Overall, aloe vera has many potential benefits, including antimicrobial and antibiofilm activities against Gram-negative bacteria, Gram-positive bacteria, and Candida albicans. It has also been studied for its moisturizing effects in the treatment of dry skin associated with occupational exposure, where aloe vera gel gloves improved skin integrity, decreased the appearance of fine wrinkles, and decreased erythema. However, it is important to note that some studies have found both negative and positive results in bacterial and mammalian cell genotoxicity assays using Aloe barbadensis-derived material.
