ABSTRACT
Lichens are composite organisms comprising of mycobiont (a fungal partner) and a photobiont (an algal or cyanobacterial partner) and represent an ecologically stable and obligate symbiotic interaction. Lichens produce characteristic lichen metabolites that do not occur normally in other organisms. The lichen genus ((Ramalina Ach.): Fungi (unicellular organisms) > Ascomycetes (nonmotile spores) > Lecanorales (fungi forming) > Ramalinaceae) is widely studied lichen genera comprising of >240 species. Primary and secondary metabolites were identified, such as salazinic acid, usnic acid, sekikaic acid, etc. Several Ramalina species are used traditionally as medicine, food, and spice. Biological activities of Ramalina Ach. have been reported, such as anti-inflammatory, antiviral, antimicrobial, anti-oxidant, enzyme inhibitory, insecticidal, cytotoxic, anthelmintic, and immunostimulatory. The present chapter has focused on the chemistry, ethnobotanical uses, and pharmacological activities of various Ramalina species.
