Aloe vera: Ancient knowledge with new frontiers

Abstract Background There are many plants with interesting pharmaceutical activities but Aloe vera is probably the most applied medicinal plant worldwide. Since biblical times, aloe has been used for its purgative effect, skin disorders healing and beauty treatments. Scope and approach For this study, an extensive review on Aloe vera was carried out, including its main uses, components (both nutrients and bioactives), biological activities, and applications. Future trends were also assessed. Key findings and conclusions Aloe possesses numerous activities including, anticancer, antioxidant, antimicrobial, antiallergic, anti-inflammatory, immunomodulatory, hepatoprotective, antiulcer and antidiabetic. Some of these activities are due to the presence of polysaccharides (acemamman; glucomannan). A wide variety of commercial products based on Aloe vera are available on the market. However, the knowledge of the relationship between biological and therapeutic properties and its components has to be clearly defined in order to know the exact mechanism of action to develop effective new products, namely pharmaceuticals. The knowledge of the factors that affect Aloe vera variability, such as processing conditions, is also of great importance to be able to standardize the final products.