Fungi and Water
Chuong Pham-Huy, Bruno Pham Huy in Food and Lifestyle in Health and Disease, 2022
There are about 200,000 fungus species found worldwide, among 1–1.5 million estimated species (4, 9). They are one of the most important groups of organisms on this planet. The kingdom Fungi is divided into four major phyla or divisions: Chytridiomycota, Zygomycota, Ascomycota, and Basidiomycota (1, 4–8). The two fungal phyla that produce large, visible fruit bodies are the Ascomycota and Basidiomycota. The Ascomycota contains at least 40,000 different species worldwide, including morels and truffles, cup fungi, and most of the lichens, as well as microscopic molds and yeasts (10). The group Basidiomycota, also known as basidiomycetes, contains from 30,000 to 35,000 different species and includes many familiar fungi, including edible and poisonous mushrooms, bracket fungi, chanterelles, and so on (10). Lichens are not fungi but arise from algae or cyanobacteria and live in common with some fungi.
Secondary Metabolites from Lichen Genus (Ramalina Ach.): Applications and Biological Activities
Megh R. Goyal, Durgesh Nandini Chauhan in Assessment of Medicinal Plants for Human Health, 2020
Lichens are self-supporting, ecologically obligate, outstandingly successful, and stable symbiotic association of a photosynthetic partner (a photobiont: a cyanobacterium or an alga) and a fungal partner (a mycobiont: an ascomycete or basidiomycete member). It is estimated that about 19% of all fungi have been lichenized. Lichens are cosmopolitan in distribution and occur in tropical and temperate regions, deserts, arctic regions, and high mountains. Together with mosses, lichens cover about 8–10% of terrestrial ecosystems. Lichens usually occur in one of the three types of growth forms: viz. crustose, foliose, and fruticose (Fig. 13.1; Appendix I) and are capable of growing on rocks (saxicolous), soil (terricolous), barks (corticolous), and leaves (foliicolous). Lichens are considered valuable as bioindicators of air pollution. Lichens are used traditionally for purposes, such as food, fodder, spices and flavoring agents, sources of dyes, for decorative purposes, preparation of perfumes and alcohol, and as medicine to treat several diseases or disorders.
The Renaissance
Scott M. Jackson in Skin Disease and the History of Dermatology, 2023
Mercurialis addressed lichen, known today as impetigo, a disease that can affect the whole body, but particularly arose on the face and chin. Lichen, per Mercurialis, was dangerous because it can spread over the entire face, and involve the eyes, or it may cause disfigurement; it was identified by its numerous round sores and broad plaques with itching, burning, and roughness.94 Mercurialis stirred up a controversy involving lichen and another ancient skin disease, mentagra (see Chapter 4), and he claimed that they two conditions were not the same as Pliny had suggested.95 His reasons: lichen was an old disease described by Hippocrates, and Pliny's mentagra was new; lichen of the chin, according to Galen, was painful and itchy, and dangerous, while Pliny's mentagra was not painful or dangerous; and finally, Pliny's mentagra affected the eminent men of Roman society, while lichen affected anyone.96 Such was the type of discourse that can be found throughout Mercurialis' work. Treatment for lichen includes the same administered for pruritus, scabies, and lepra. Mercurialis pointed out that lichen can evolve into scabies and lepra, thus completing a continuum of disease in which the main dermatologic diseases are all connected to one another.
Aqueous extract of oakmoss produces antihypertensive activity in L-NAME-induced hypertensive rats through sGC-cGMP pathway
Published in Clinical and Experimental Hypertension, 2021
Ayoub Amssayef, Mohammed Ajebli, Mohamed Eddouks
Lichens are a symbiotic association of a fungus with a green alga or cyanobacterium (8). Recently, there was a growing attention over lichens as a new source of bioactive molecules. Traditionally, more than 60 lichens genera are commonly used for treating wounds, respiratory and digestive disorder, inflammation, diabetes and hypertension (9). Besides, it has been reported that lichens contains more than 1050 secondary metabolites that exert a wide array of pharmacological activities including antibiotics, analgesic, anti-inflammatory and cytotoxic actions (9). Evernia prunastri (L.) or Oakmoss is a lichen species, belongs to Parmeliaceae family. In Morocco, Oakmoss is called “Lahiat alshaykh”, used in the traditional medicine to treat coughs, tuberculosis, anxiety, and stimulate appetite (10–12). Moreover, it has been proved that Oakmoss exhibits antioxidant, antimicrobial and anticancer properties (13).
Radiosensitizer effect of usnic acid on Biomphalaria glabrata embryos
Published in International Journal of Radiation Biology, 2018
F. T. J. Santos, W. N. Siqueira, M. L. O. Santos, H. A. M. F. Silva, J. L. F. Sá, T. S. Fernandes, N. H. Silva, E. J. França, E. B. Silva, A. M. M. A. Melo
Lichens, symbiotic associations between fungi and algae, are the source of a variety of bioactive compounds, mainly derived from their secondary metabolism and having applications in medicine, the textile industry, cosmetics and food (Kosanić et al. 2012; Manojlovic et al. 2012; Paudel et al. 2012). Usnic acid, dibenzofuran found in several species of lichens, is one of the most studied lichen metabolites and one of the few commercially available today. A number of biological activities are attributed to this metabolite, and its analgesic, antiviral, antiparasitic, antimicrobial, anti-inflammatory, antiproliferative, antitumor and antioxidant effects are reported (Shang et al. 2014; Su et al. 2014). Such characteristics make usnic acid a promising candidate for bioassays that can verify its radiosensitizing activity.
Usnic acid and its derivatives for pharmaceutical use: a patent review (2000–2017)
Published in Expert Opinion on Therapeutic Patents, 2018
Olga A. Luzina, Nariman F. Salakhutdinov
It has been demonstrated that natural products play a dominant role in the discovery of leads for the development of drugs for the treatment of human diseases [1]. Most of them belong to the domain of plant-derived compounds, and much of nature’s ‘treasure trove of small molecules’ remains to be explored from marine, microbial, and fungal environments. Lichens are composite organisms consisting of a symbiotic association of a fungus (the mycobiont) with a photosynthetic partner (the phytobiont), usually either a green alga or cyanobacterium. The morphology, physiology, and biochemistry of lichens are very different from those of isolated fungi and alga in culture. Over the past two decades, there has been renewed and growing interest in lichens as a source of novel, pharmacologically active biomolecules [2]. Of the hundreds of known secondary lichen metabolites, the dibenzofuran derivative, usnic acid (UA), is without doubt the most extensively studied. Usnic acid is widely distributed in species of Cladonia (Cladoniaceae), Usnea (Usneaceae), Lecanora (Lecanoraceae), Ramalina (Ramalinaceae), Evernia, Parmelia (Parmeliaceae), and other lichen genera. Lichens produce much UA, up to 8% of the dry weight of thalli. Its content in thalli undergoes broad seasonal variation, reaching a maximum in the late spring and early summer and low levels in autumn and winter. The usnic acid content depends on geographic locality, correlating with the time of summer solstice, insolation, and temperature [3]. Since Usnea spp. synthesize and excrete UA in response to an environmental influence, the UA content may be increased artificially up to 31% [4].
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