What is Lichen Sclerosus?

Lichens are a symbiotic complex of algae and fungi. Because the bacteria and algae are closely combined for a long time, a morphological, structural, physiological, and genetically formed a single fixed organism, so lichen is listed as a lichen plant door. There are about 26,000 species of 500 genera in this genus. ^[1]

Lichen plants can be divided into three types according to their morphology: shell lichen, leaf lichen and branch lichen. ^[2]

According to the distribution status of algae cells in fungal tissues, lichens can be divided into two types: same-layer lichens and hetero-layer lichens. ^[3]

Most lichens are hi-light plants and require fresh air in the habitat. It is not resistant to air pollution, so few lichens grow in large cities and industrial parks. However, the lichen is very cold and drought resistant. It can be dormant when dry and revived after rain. Can grow on rocks, deserts or bark. For example, in areas where alpine, tundra and north and south poles cannot survive. ^[1]

Lichen plants are usually vegetatively propagated. The fronds are broken into several lobes, and each shard develops into a new frond, or vegetative propagation such as powder buds and coral buds are produced on the fronds. Sexual reproduction is carried out only by the fungi it produces. As commensal fungi in lichens are mostly ascomycetes, the most common types of ascomycetes are produced through sexual processes. Ascospores are released from the ascus after maturation and germinate into mycelium under appropriate conditions. If suitable symbiosis cells are combined with each other, they can develop into new lichen plants. Algae cells in lichens multiply mainly by cell division. ^[3]

Lichens play a role in soil formation. The lichen growing on the rock surface, the various lichenic acids secreted can erode the rock surface, gradually cracking and breaking the rock surface, and the natural weathering effect gradually forms a soil layer on the rock surface, creating for the growth of other higher plants The conditions. Therefore, lichens are often referred to as "plant potentiators" or pioneer plants. ^[4]

Lichens have a wide range of uses. Lichen has secreted more than 100 kinds of lichen acid, many of which have strong antibacterial ability. Species such as usnea and litmus that have been recorded in the Compendium of Materia Medica can be used to extract antibiotics. In recent years, a variety of lichen polysaccharides and heterolichen polysaccharides have been found to have anti-cancer effects. ^[5]

Some lichens can be eaten, such as the stone fungus, which is a specialty of China and Japan. It is delicious and considered as one of the mountain treasures. ^[5]

Lichens can be used as industrial raw materials. For example, the dye lichens can be used to extract dyes, and litmus pigments extracted from dyes and litmus can be used to make acid qualitative reagents. ^[5]