A Review on Nutritional Composition, Phytochemistry and Pharmacological Properties of Lichen

Lichen shows a symbiotic relationship between fungi and algae. Lichens are slow-growing organisms, but they are found in different kinds of habitats throughout the world. Lichens are renowned for their diverse application; particularly in traditional medicine, due to the presence of active substances within them. Lichens are an important source of natural resources; they are used in various aspects of human life, including as food, fodder, dyes, perfume, spice, and for various miscellaneous purposes. Few species of lichens are identified as a source of food. Though many researchers are concerned about lichens because of their secondary metabolites, there has been limited exploration of research specifically focused on edible lichens. This review focused on the uses of lichen as food and analyzed their nutritional value and health benefits of secondary metabolites of lichens. So, these may provide new opportunities to the researchers for the research on edible lichen and medicinal properties derived from lichen. Theoretically, it is well known that lichens are rich in nutrition, their extracts and active substances also have various health benefits including anticancer, anti-inflammatory, antioxidant, antidiabetic, antibacterial, and antifungal activities, etc. However, the nutrient compounds that are derived from edible lichens and the activity of their active substances remain unsolved. Therefore, more work is needed on the edibility of lichens. This review may provide new directions to the researchers on lichen research in the future.