Antimicrobial activity in some lichens from south Spain has been studied. Some lichenical substances are also identified. The structures of all compounds were elucidated by physical, spectral and chemical methods. A very high activity against Gram-positive bacteria has been observed in lichens containing usnic acid.

Lichens and mosses often share the same environmental conditions where they compete for substrate and other essential factors. Lichens use secondary metabolites as allelochemicals to repel surrounding plants and potential rivals. In mosses, endoreduplication leads to the occurrence of various ploidy levels in the same individual and has been suggested as an adaptation to abiotic stresses. Here,...

Pendulous lichens dominate canopies of boreal forests, with dark Bryoria species in the upper canopy vs. light Alectoria and Usnea species in lower canopy. These genera offer important ecosystem services such as winter forage for reindeer and caribou. The mechanism behind this niche separation is poorly understood. We tested the hypothesis that species-specific sunscreening fungal pigments prot...

Lichens are specific symbiotic organisms harboring various microorganisms in addition to the two classic partners (algae or cyanobacterium and fungus). Although lichens produce many antibiotic compounds such as (+)-usnic acid, their associated possess ability colonize an environment where antibiosis exists. Here, we have studied behavior of several lichen-associated bacterial strains presence a...