Mushrooms as Potential Sources of Active Metabolites and Medicines

Mushroom polysaccharides are exploited and developed as a functional food substance such as ganoderan from Ganoderma lucidum, pleuran from Pleurotus species, lentinan from Lentinus edodes, calocyban from Calocybe indica, schizophyllan from Schizophyllum commune most of which are the representatives of D-glucans having common (1→3) or (1→6) β-linked glucose backbones (Villares et al., 2012; Badalyan, 2014). Commonly found monosaccharides in mushroom polysaccharides are mannitol, mannose, glucose, trehalose, rhamnose, xylose, galactose, arabinose, xylose, fucose, fructose, etc. (Valverde et al., 2015). Polysaccharides are one of the most common and potent compounds derived from mushrooms and exhibit various human-beneficial activities such as anti-inflammatory, antitumor, and immunomodulatory activities (Pant et al., 2020). The common functioning mechanisms of various mushroom polysaccharides that involves the activation of the above three activities are the activation of neutrophil, cytotoxic, cytokines (interferons, interleukins, and colony-stimulating factors), natural killer cells, monocytes, dendritic cells, and macrophages (Wasser, 2011). The health benefits of mushroom polysaccharides via the regulation of gastrointestinal and gut microbiota function (Prajapati et al., 2021). Mushroom polysaccharides as dietary fibers display an interaction process with colonized microbiota gut in gastrointestinal tracts that might change several variations of gut microbiota which impacted the health level of the host (Kong et al., 2016). Polysaccharides that obtained from the mushrooms might be degraded by the gut microbiota and some bacterial groups absorb them as an energy source that displays stimulation effects on the production of beneficial compounds such as short chains fatty acids like butyrate, valerate acid, acetate, and propionate and their propagation (Zhu et al., 2016; Ma et al., 2017). During the process of fermentation, the extracts of Ganoderma lucidum mostly composed of polysaccharides and have the ability to increase the abundance of Bifidobacteria (Yamin et al., 2012); Zhang et al. (2017) demonstrated that the Ganoderan is extracted from the Ganoderma sp. and having β-(1→3)-D-glucans with β-(1→6)-D-glucopyranosyl branches and the molecular weight is around 1.2 × 10⁶ Da to 4.4 × 10⁶ Da (Üstün et al., 2018; Ziaja-Sołtys et al., 2020). Additionally, due to the daily supplementation of Ganoderma lucidum polysaccharide strain, the abundance of bacteria like Roseburia, Lachnospiraceae, and Lactobacillus with health benefits to host enhanced significantly (Li et al., 2016). Colonized bacteria of the human colon utilized the β-glucans obtained from the mushroom and displays the potential to improve the health of humans by selectively changing the abundances of bacteria such as lactic acid bacteria and bifidobacterial (Wong et al., 2005). High molecular weight polysaccharides greater than 300 KDa that isolated from the extracts of water of Ganoderma lucidum mycelium which produce anti-obesity as well as microbiota-modulating effects like reduced endotoxin-bearing proteobacteria level as well as the ratio of Firmicutes/Bacteroidetes, decreased bodyweight, insulin resistance, and inflammation in mice fed a high-fat diet (Chang et al., 2015). The composition of the gut microbiota might be regulated by Inonotus obliquus polysaccharides as well as in mice having chronic pancreatitis (Hu et al., 2017).

Lentinan, from Schizophyllum sp. also has a β-(1→3)-glucan with a β-glucopyranosyl group linked by β-(1→6) linkage and molecular weight around 450 kDa (Pandya et al., 2019). Pleuran is a water- as well as alkali-soluble polysaccharide that is extracted from the Pleurotus sp. and has β-(1→3/1→6)-D-glucan or α-(1→3)-D-glucan structurally (Baeva et al., 2019). Grifolan extracted from the Grifola sp. of mushroom with gel-forming β-(1→3)-D-glucan. Molecular weight is around 770 kDa to 1650 kDa (Giavasis, 2014).

Kristiansen (2015) polysaccharide-K or PSK is extracted from the Trametes sp. with protein-bound β-glucan and having β-(1→4)-glucan with lateral β-(1→6)- glucopyranoside chains. It has a molecular weight of around 94 kDa (Zong et al., 2012). Another proteoglucan extracted from Trametes sp. is polysaccharide-protein complex. Polyporus polysaccharide is extracted from Polyporus sp. of mushroom with (1→3)- β-glucan backbone and (1→6)-β-glucopyranose side chain. Its molecular weight is around 1.6 × 10⁵ Da (Zong et al., 2012). Polysaccharides that extracted from the Agaricus sp. have several structural variants like an acidic β-(1→6)/α-(1→3)-glucan, an acidic β-(1→6)/α-(1→4)-glucan and β-(1→6)/β-(1→3)- glucan with very broad molecular weight starting from 380 kDa to 10,000 kDa (Giavasis, 2014).

It has been found that the polysaccharide extracted from edible mushrooms such as Auricularia (jelly ears fungi) has a β-(1→3)-D-glucan that is linked with two residues of β-(1→6)-D-glucosyl for every three main chain glucose moiety. It has a molecular weight of around 2.1 × 10³kDa (Miao et al., 2020). Polysaccharides that extracted from Cordyceps sp. having α-(1→4)- D-glucan linked with the branches of α-(1→6)-D-glucan with a molecular weight of around 1180 kDa (Zong et al., 2012).

In mushrooms, proteins and peptides are the important bioactive nutraceuticals having various health benefits like some enzyme inhibition activities, increased in the absorption and digestion of exogenous nutritional ingredients and the immune function modulation to help the host defending the invasion of pathogens as well as the inhibition activities of few enzymes (Valverde et al., 2015). It has been found that the proteins and peptides in mushrooms have pharmaceutical potential such as ribonucleases, lectins, ribosome-inactivating proteins, laccases, and fungal immunomodulatory proteins (Xu et al., 2011). Lectins are the glycol or non-immune proteins that binds with the carbohydrates of cell surfaces and possess important activities like antiviral, antitumor, antifungal, immunomodulatory properties, antibacterial, etc. (Singh et al., 2014) whereas fungal immunomodulatory proteins are used as adjuvants for the treatment of tumors because of their important activity in suppressing the invasion as well as metastasis of tumor cells (Lin et al., 2010).

Ribosome inactivating proteins are able to inhibit the fungal proliferation as well as HIV-1 reverse transcriptase activity (Puri et al., 2012). Sanchez observed anti-tumor and immunomodulatory effects on breast cancer MCF7 cells, hepatoma HepG2 cells, human leukemic T cells (Sanchez, 2017). Further, there were also anti-viral studies observed on the reverse transcriptase activity on the immunodeficiency virus (HIV-1) which showed inhibitory function. Usually, edible mushrooms possess between 19 to 39% of protein by dry weight while being a part of a complex network of fungal cells (Reddy, 2016).

Dahima et al. (2020) demonstrated that the pleurostrin extracted from the Pleurotus ostreatus is a 7 kDa anti-fungal peptide. It has also been found that the cordymin extracted from the mushroom Cordyceps militaris and Cordyceps sinensis is an anti-inflammatory peptide having a molecular weight of around 10,906 kDa. (Elkhateeb and Daba, 2019; Ashraf et al., 2020). Xylose-specific lectins extracted from Xylaria hypoxylon with a molecular weight of around 28.8 kDa show anti-tumor as well as anti-mitogenic activities (Büttner et al., 2019). Laccases that are isolated from Pleurotus ostreatus and Pleurotus eryngii display an anti-viral property (Wang and Ng, 2006; Ilyicheva et al., 2020); Lynn (2017) has also been found that there are several FIPS that have been isolated successfully from different mushrooms like Fip-gts from Ganoderma tsugae, Fip-fve from F. velutipes, and Fip-vvo from Volvariella volvacea. According to Chang et al. (2010) and Zhao et al. (2020) Fip-fve has been applied successfully for tumor immunotherapy. A 9 kDa RIP Marmorin with anti-tumor properties has been isolated from the Hypsizygus marmoreus (Wong et al., 2018).

Terpenes that are found from the mushrooms are regarded as volatile unsaturated hydrocarbon clusters that are categorized as mono, sesqui, di, and triterpenoids (Duru and Cayan, 2015). There are various types of sesquiterpenoids that are obtained from the mushrooms such as drimane, aristolane, sterpurane, cuparene, lactarane, spiro, bisabolane, fomannosane, and nordasinane. According to Duru and Cayan, mostly the diterpenoid mushrooms were detected as cyathane type while the triterpenoid compounds were detected as lanostane type that isolated from the mushrooms (Duru and Cayan, 2015). Various fungal sesquiterpenic molecules are effective against Leishmania mainly, Eimeria tenella, L. donovani, L. infantum, Acanthamoeba castellanii, Trypanosoma brucei, T. cruzi, Neospora caninum, T. gondii, and other parasites (Lenzi et al., 2018). Lentinus species can yield various sesquiterpenes. Lenzi et al. (2018) and Kumari et al. (2019) demonstrated that the sesquiterpenes panepoxydone and hypnophilin might be isolated from the ethyl acetate extracts of mushroom Lentinus strigosus whereas some of the sesquiterpenes such as dihydrohypnophilin, panepoxydione, and panepoxydone were isolated from the ethyl acetate extracts of fungus Lentinus conatus. According to Breitmaier (2006), Linalool is the monoterpene derivative with anti-bacterial activity. Sesquiterpenes are mainly composed of three isoprene units with general molecular formula C₁₅H₂₄. They are mainly produced by some fungi and plants. Geosmin is the common sesquiterpene produced by actinomycetes. Additionally, these mushroom terpenes have been associated with various health benefits such as antiviral (Asakawa et al., 2014), anticholinesterase (Dundar et al., 2015), anticancer (Song et al., 2013; Klaus et al., 2017), antioxidant (Boonsong et al., 2016; Kumari et al., 2021), antimalaria (Ozturk et al., 2015), anti-inflammatory (E1 Enshasy and Hatti-Kaul, 2013; Elsayed et al., 2014) activities. These multiple sesqui, di, and triterpenoids were obtained from various species of mushrooms like Ganoderma species, F. velutipes and Pleurotus. There are two main terpenes such as Flammulinolides and Flammulinol that are isolated from F. velutipes having cytotoxicity against the three tumor cell lines KB, HeLa, and HepG2 while terpenes that isolated from the Pleurotus species revealed very essential bioactivities like two sesquiterpenoids as well as five monoterpenoids having anti-inflammatory effects.

Lee et al. (2011) found that n-butyl ganoderate H as well as methyl ganoderate A acetonide from G. lucidum owes the ability of anti-acetylcholinesterase effect for the Alzheimer’s and related neurodegenerative diseases.

The phenolic compounds of mushrooms which are regarded as aromatic hydroxylated compounds with one or more hydroxyl groups as well as aromatic rings mainly comprise tannins, phenolic acids, oxidized polyphenols, hydroxybenzoic acids, lignans, flavonoids, stilbenes, and hydroxycinnamic acids (D’Archivio et al., 2010).

Additionally, these compounds provide protection against various degenerative disorders like cardiovascular diseases, cancer, brain dysfunction, and aging (Finimundy et al., 2013). They also have an excellent antioxidant capacity as well as antiviral, anti-inflammatory, antiatherogenic, cardioprotective, anticancer, antimicrobial, antithrombotic, antiallergenic and vasodilator effects (Balasundram et al., 2006; Ferreira et al., 2009; Heleno et al., 2012a). From the edible mushroom such as Phellinus baumii Pilat belongs to Hymenochaetaceae family, three phenolic compounds have been found that have the ability to inhibit LPS-stimulated nitric oxide (NO) production in RAW264.7 cells (Lee et al., 2017).

From the mushroom Phellinus species, the phenolic compound Hispidin has been derived which possesses anti-inflammatory activities via suppressing the ROS mediated NF-κB pathway in the macrophage cells of mouse (Shao et al., 2015); Chang et al. (2011) isolated phenolic compounds from the mushroom Phellinus linteus showed the anti-inflammatory mechanisms of decreasing the level of MDA in the edemapaw by enhancing the effect of SOD, GPx, and GRx in the liver, further the suppression of TNF-α and NO. Next, Patel and Goyal (2012) extracted hispolon from Phellinus species which induce epidermoid and gastric cancer cell apoptosis, and regardless of p53 status, hispolon inhibited bladder cancer and breast cell growth. According to Lai et al. (2010) the dichloromethane extracted from Ganoderma lucidum composed of phenolics, flavonoids, alkaloids, and terpenoids and also displayed anti-human papillomavirus 16 (HPV 16) E6 oncoprotein effect. When epidermoid cervical carcinoma (CaSki) cells are treated with the crude dichloromethane extracts, HPV 16 E6 production gets suppressed. In eight types of edible mushrooms such as Pleurotus ostreatus, Cantharellus cibarius, Agaricus bisporus, Lactarius deliciosus, Boletus edulis, Craterellus cornucopioides, Hygrophorus marzuolus, and Calocybe gambosa the contents of total flavonoid and total phenolic has been evaluated.

Ergosterol is one of the major sterols produced by mushrooms and has shown important antioxidant properties (Guillamon et al., 2010). It also plays an important role in the prevention of cardiovascular diseases (Kalac, 2013). They are detected as tocopherols and considered as effective as well as novel natural antioxidants and have major biological activities for the protection against microbial and cardiovascular diseases and degenerative malfunctions (Heleno et al., 2012a, 2015b; Jaworska et al., 2015). Linoleic acid participates in various physiological functions such as decreasing the inflammatory level via inhibiting the production of NO and also suppressing the expression of pro-inflammatory cytokines like TNF-α, IL-6, IL-1β, and NOS2 in RAW 264.7 cells (Saiki et al., 2017). The decreasing impact on the Alzheimer’s disease risk correlates with its inhibition effects against the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) (Ozturk et al., 2014).

Xylose, maltose, rhamnose, trehalose, mannitol, arabinose, fructose, sucrose, fucose, glucose, and mannose are the properties of carbohydrates that have been quantified in various mushrooms (Zaidman et al., 2005; Zhang et al., 2007; Ferreira et al., 2009; Heleno et al., 2012b). The antitumor polysaccharides which are isolated from mushrooms can be acidic or neutral in nature and have strong antitumor action. Moreover, they also differ in their chemical structures. Glycans which extend from homopolymers to highly complex heteropolymers and exhibit the antitumoral effect. Due to the activation of the immune system, mushroom polysaccharides have antitumor action. Wasser (2002) and Zhang et al. (2007) observed that mushroom polysaccharides cannot kill the tumor cells directly. These compounds prevent the body from stress, moreover, they can produce half the reduction in tumor size and extend the survival time of tumor-bearing mice.

According to De Groot and Hellingwerf (2001), McIntosh et al. (2005), Schmid et al. (2001) β-glucans are the main polysaccharides that are found in mushrooms whereas 50% of the fungal cell wall mass is founded by β-glucans. For the industry, it is very essential due to their excretion into the cell growth medium and making their recovery. Its chemical characterization and purification are very simple. These β- glucans are highly responsible for the antioxidant, anticholesterolemic, anticancer, neuroprotective, immunomodulating activities of several edible mushrooms (Falch et al., 2000; Ishibashi et al., 2001; Kataoka et al., 2002; Khan et al., 2013). They are also essential in protection from cancer as well as infectious diseases and also recovered the aid patients from radiotherapy and chemotherapy (Manzi et al., 2001; Chen and Seviour, 2007). Consequently, reinforcing as well as activating the host immune system is the best strategy for inhibiting the cancer cells’ growth (Daba and Ezeronye, 2003; Finimundy et al., 2013).

Mostly the edible mushrooms contained polyunsaturated fatty acids and help to decrease the serum cholesterol level. Tocopherols are the natural antioxidant compounds found in the lipidic fraction as they act as free radical scavenging peroxyl components produced from several reactions. These antioxidants are protective against cardiovascular diseases, degenerative malfunctions, and cancer. Linoleic acid, an essential fatty acid to humans, decreases triglyceride levels, arthritis, cardiovascular diseases, and blood pressure (Hensley et al., 2004; Ferreira et al., 2009; Heleno et al., 2012a; Reis et al., 2012).

Coriolus versicolor is one of the dried fruiting body or mycelia of Coriolus versicolor. This Coriolus versicolor is visible as a fan-shaped mushroom having a wavy margin and colored concentric zones. This obligate aerobe is commonly found year-round on dead logs, branches, stumps, and tree trunks. This fungus occurs all over the wooded temperate zones of North America, Asia, and Europe and is the most common shelf fungus in the Northern Hemisphere. This mushroom belongs to the family Basidiomycotina. This Coriolus versicolor has many different names such as Boletus versicolor, Polystictus versicolor, Trametes versicolor, Agaricus versicolor, Poria versicolor, Yun-zhi (China), i.e., cloud-like mushroom probably due to its wavy surface that covered with fluff, Kawaratake (Japan) which means mushroom by the riverbank, Turkey-tail (North-America) as it fan-shaped zoned having shades of white, gray and brown in color on the upper surface and on dead logs, it grows in overlapping clusters and Polyporus versicolor.

This Coriolus versicolor fruiting body has brackets 3 to 5 cm across which are flattened, tough, thin, and semi-circular whereas young brackets are flexible. Mostly these brackets occur in tiers and spread along the branches. The upper surface of the Coriolus versicolor fruiting body is velvety and attractively marked having concentric zones of several colors, i.e., black, gray, yellow, greenish, and brown. Mostly the margin of the fruiting body is wavy. The mushroom has white spores which are cylindrical (4–6 μm × 2–2.5 μm) and oblong. The spores and fruiting bodies do not form in agitated submerged culture and grow as pelleted or dispersed mycelium. More than 120 strains of Coriolus versicolor have been recorded (Soothill and Fairhurst, 1977). The fruiting body of Coriolus versicolor is harvested for its medicinal and nutritional values just like all other mushrooms. This fungus is known to have potential pharmacologically active secondary metabolites which belong to small molecular weight compounds in addition to the minerals and major macromolecules, i.e., carbohydrates, lipids, and proteins (Habtemariam, 2020). In European origin, the phenolic composition of Coriolus versicolor fruiting body about thirty-eight phenolic compounds have been identified by HPLC-MS/MS- based study belonging to the hydroxycinnamic acids and flavonoid such as flavonols, bioflavonoids, isoflavonoids, flavones (Janjusevic et al., 2017).

The most common species within the genus is Trametes versicolor which is commonly known as Turkey tail and has been reported on 295 woody plant species including angiosperms and conifers (Grand and Vernia, 2002). Trametes versicolor belongs to the domain ‘eukaryota’ and kingdom ‘fungi’ and has phylum and subphylum, i.e., Basidiomycota and Agaricomycotina whereas belonging to the class Agaricomycetes and subclass Agaricomycetidae. It has order polyporales and belongs to the family polyporaceae and species Trametes versicolor. This Trametes versicolor is commonly widespread across Ireland and Britain and this Turkey tail fungus occurs all over the mainland of Europe from northern Scandinavia right down to the Mediterranean region., This wood-rooting fungus is also found in Asia and North America.

In 1753, Carl Linnaeus originally described Trametes versicolor and gave it the binomial name Boletus versicolor and further, it was as recently as 1939 that this species renamed as Trametes versicolor by Czech mycologist Singer (1975). Trametes versicolor is one of the cosmopolitan genera of white-rot polypores and the most familiar genera of polypores, its species-level taxonomy is unsettled. These species are available in about all forest ecosystems and are also found often on many genera of hardwoods in every part of northern temperate forests. Apart from their noteworthy role in the ecosystem’s recyclers and decomposers, the mushrooms have various biological activities including antibacterial, anticancer, insecticidal, antioxidant, anti-proliferative, anticoagulant, antifungal, antidiabetic, hepatoprotective, antiparasitic, antiviral, and anti-inflammatory properties (Atomachi, 1988). More than one hundred and twenty strains of Coriolus versicolor have been recorded in the Compendium of Chinese Materia Medica. This Coriolus versicolor has cold properties and is slightly sweet in taste, exerting its effects through the spleen and liver according to the theory of traditional Chinese medicine practices (Wasser, 2010). Coriolus versicolor is also useful for strengthening the physique, removing toxins, dispelling heat, increasing the host’s immune function, and enhancing the energy and spirit. Coriolus versicolor is often used for several types of cancers, upper respiratory, digestive, and urinary tract infections and chronic hepatitis in the clinical practices of traditional Chinese medicine. Picture of Coriolus versicolor shown in Figure 8Aa.

Agaricus campestris is frequently known as meadow or field mushroom. Agaricus campestris has pileus 3 to 6 cm wide. This Agaricus campestris is hemispherical to convex in nature and becomes planar at maturity. Agaricus campestris when young are pure white in color and become yellowish at the center with age and sometimes depressed at the center. Its surface is smooth, dry, and silky fibrillose whereas sometimes it is a few grayish to brown fibrils or fibrillose over the cap surface. Its complete margin is expanded beyond the gills frequently hung with veil remnants. On exposure, Agaricus campestris has firm, thick, reddening, and white flesh. It has a mild taste and a fungal odor. It has close Lamellae and it is pinkish white in button then bright pink and then becomes chocolate brown. The length of its stipe is 3–7 cm long and 0.5–1 cm diameter. It has been found that at base it is attenuated or bulbous and centric. It is white to whitish in color and has a smooth surface above the veil. It often has few fibrils below which are stuffed or hollow, silky, and the context is white slight reddening on exposure. At its best it has an annulus of white color which has a thin and skirt-like appearance. The print of its spore is chocolate brown. The spore is 5.5–7 μm × 3.5–5 μm and elliptical.

Agaricus mushroom is a fungus that is used for ongoing liver disease, cancer, digestive problems, high cholesterol, type 2 diabetes, arteriosclerosis, bloodstream disorders, heart disease, osteoporosis, and stomach ulcers. This mushroom is also used to boost up the immune system as well as for physical and emotional stress. In Agaricus campestris, the presence of insulin-releasing, anti-hyperglycemic as well as insulin-like activities has been reported. It also has been found that the lectins that isolated from the Agaricus campestris enhance the insulin that releases by isolated ret islets of Langerhans (Ewart et al., 1975; Ahmad et al., 1984a,b). It is also used in the treatment of diabetes (Gray and Flatt, 1998; Usman et al., 2021). Picture of Agaricus sp. shown in Figure 8Ab.

Ganoderma species is one of the facultative parasites that live as saprobe by roots of trees, feeding off as well as rooting stumps. They are pathogenic and wood-decaying fungus that causes stem and root rot in the perennial crops as well as butt root (Coetzee et al., 2015). The species of Ganoderma also plays a vital role in the breakdown of woody plants for the mobilization of nutrients. It is also useful in bioremediation due to the lignocellulose decomposing enzyme’s mechanism and also useful in bioenergy production (Coetzee et al., 2015; Bijalwan et al., 2020).

The fruiting body of Ganoderma contains polysaccharides that are useful in the inhibition of tumor growth. One of the major constituents is the glucans present in the cell wall of fungi. Ganoderma enhances the bodily resistance against tumor growth and also the immunity function. It also induces interferon production as well as kills the cells of the tumor within the body (Jong and Birmingham, 1992). It is also used in the treatment and prevention of diabetes, infections, cancer, immune system disorders, hepatoprotection and bacterostasis, etc. (Deepalakshmi and Mirunalini, 2011). Studies have shown that the regular consumption of Ganoderma has been linked to prolonged life, relaxed body, and alleviation of the symptoms of aging (Yuan et al., 2018).

Ganoderma lucidum have a 3 to 23 cm wide pileus. It is kidney-shaped and elongated. At maturity, it is more or less fan-shaped and becomes red to reddish-brown when gets mature. When it is young, it often has zones of bright yellow and white toward the margin. It has up to 2 cm deep tubes as well as 0.1 cm of pores. It is whitish in color, usually bruising brown. It has 3 to 12 long stipes 1 to 2 cm thick. It is cylindrical, dark red to black with varnished crust, has a brown print spore, smooth and twisted in nature (Vishwakarma et al., 2011).

Ganoderma lucidum is widely used in the treatment of bronchitis, gastric ulcer, hepatopathy, asthma, insomnia, chronic hepatitis, nephritis, arthritis and hypertension, weakness, fatigue, and cough (Halpern and Miller, 2002). It is also used in India in the treatment of joint pain (Harsh et al., 1993). It also has some very significant properties like hepatoprotective, anti-cancer, anti-atherosclerosis, very strong immunomodulating effects, anti-oxidant, anti-HIV, nephroprotective, anti-tumor, anti-hepatotoxic, cardiovascular, and respiratory properties (Chang, 1995; Stamets, 2000b). It is also found out that the substances extracted from the mushrooms can decrease the level of blood pressure, blood sugar level, inhibition of platelet aggregation as well as blood cholesterol, etc. (Ajith and Janardhanan, 2007). A picture of Ganoderma is shown in Figure 8Ac.

Hydnum is the genus of fungi that belongs to the Hydnaceae family and are significant for their unusual spore-bearing structures of teeth other than gills. Hydnum repandum and Hydnum rufescens are the two best-known edible mushrooms. Hydnum repandum has a pileus of 3 to 10 cm in diameter. It is convex and becomes nearly a plane having a central depression. Its surface is smooth to slightly scaly, dry, cream to buff-orange, or planer. In the beginning, its margin is inrolled and at maturity it becomes lobed to undulating and bruising to orange-brown. Hydnum repandum is fleshy white and often discolors to yellowish when it is bruised or exposed. Its taste and odor are peppery or mild (Vishwakarma et al., 2011).

Commonly, Hydnum repandum is known as hedgehog mushroom or wood hedgehog. Repandiol compound extracted from the Hydnum repandum shows cytotoxic activity against a variety of tumor cell types, mainly colon adenocarcinoma cells (Takahashi et al., 1992). Chloroform extracted from this mushroom has some mild antibiotic activities against Staphylococcus aureus, Bacillus subtilis, Enterobacter aerogenes, and Staphylococcus epidermidis while extract of ethanol has mild activity only against the Bacillus subtilis. Picture of Hydnum is shown in Figure 8Ad.

Coprinus is one of the tiny mushroom genera which forms fungi that consists of Coprinus comatus. This Coprinus comatus is 4 to 10 cm broad, oval, and cylindrical in nature and elongated as conical or bell-shaped as well as becomes revolute or torn at the margin. Its surface turns white to pinkish toward the margin and then becomes blackish. It has a smooth center as well as ochraceous cream, pale or buff fulvous at first, and has shaggy white to pale brownish scales often darkest at the tips. It has decurved margins that inroll at maturity. It has no or slightly pleasant taste with a mild odor (Vishwakarma et al., 2011).

Commonly, this fungus is known as shaggy ink cap, shaggy mane, or lawyer’s wig. This fungus has various bioactive functions such as its consumption helps to regulate the blood glucose level, hypoglycemic and has antitumor, antioxidative, hypolipidemic, antibacterial as well as immunomodulation effects (Bailey et al., 1984; Fan et al., 2006; Wei and Van Griensven, 2008). Picture of Coprinus is shown in Figure 8Ae.

The genus Morchella belongs to the family Morchellaceae. They have about 80 various species; one of them is Morchella esculenta that has a 3 to 5 cm diameter of pileus and is 4 to 8 cm long. This mushroom species is subglobose to ovoid and pale brownish cream and pale brown to grayish brown in color. Its surface is covered with irregularly interwoven pits of several colors or rounded pits. Its edge is thick, rounded and yellow or white in color. Its stipe is 3 to 6 cm long, having a 2 to 4 cm diameter. At base, it is bulbous, centric, or attenuated. Firstly, it appears as white in color then with age it becomes ochraceous. Just beneath the pileus, it has wrinkled as well as grooved scurfy tufts as well as it is also brittle and hollow. It has white and thin flesh with a yellow spore print. Spores are 11.5–14 μm × 19.5–23 μm ellipsoid (Vishwakarma et al., 2011).

Morchella esculenta is one of the edible morel mushrooms commonly known as Guchhi. This mushroom is used in food, medicines, and also health care. Morchella esculenta shows anti-inflammatory as well as antitumor activity against both ascites as well as solid tumors of ethanolic extracts whereas methanolic extracts prepared from its mycelia show a high content of total phenols as well as high antioxidant activity (Mau et al., 2004; Nitha et al., 2007). A picture of Morchella is shown in Figure 8Af.

Cantharellus is the genus of edible mushrooms that are locally known as golden Chanterelle or Chanterelle, which refers to the species Cantharellus cibarius. This Cantharellus mushroom belongs to the family Cantharellaceae.

The species Cantharellus cibarius has a pileus of 3 to 10 cm in diameter. At first, it appears as convex with an inrolled margin and then often becomes funnel-shaped along with wavy-margins. It is pale yellow to egg-yolk yellow to almost orange in color having some small appressed fibers. It is mildly peppery in taste as well as having a fruity odor. Underneath its smooth cap on the lower surface, it has gill-like ridges which run almost all the way down its stipe that tapers down seamlessly from the cap. It has a 3 to 5 cm long stipe 1 to 2 cm thick in diameter. It is thin, solid, and smooth concolorous the pileus. It has pale yellow to creamy white spore prints. Spores are 7–10 μm × 4–6 μm smooth and ellipsoid (Vishwakarma et al., 2011). This species of mushroom has excellent antihyperglycemic, antioxidant, wound healing, antimicrobial, iron-chelation, cytotoxicity, anti-hypoxic, anti-inflammatory activities (Kumari et al., 2011). Picture of Cantharellus shown in Figure 8Bg.

Amanita genus has around 600 species of agarics and it belongs to the family Amanitaceae. The edible species of mushrooms are Amanita rubescens, Amanita fulva, Amanita calyptrate, Amanita jacksonii, Amanita vaginata, Amanita caesarea whereas inedible mushroom species are Amanita citrina, Amanita volvata, Amanita atkinsoniana, Amanita albocreata, Amanita excelsa, Amanita sinicoflava, Amanita longipes, Amanita onusta, Amanita franchetii, Amanita flavorubescens, Amanita rhopalopus, Amanita silvicola, Amanita spreta, etc. (Phillips, 2010). There are some poisonous species, some lethally so, of Amanita such as Amanita farinose, Amanita brunnescens, Amanita pantherina, Amanita cokeri, Amanita ceciliae, Amanita crenulata, Amanita muscaria, Amanita porphyria, Amanita frostiana, etc., Amanita ocreata, Amanita smithiana, Amanita abrupta, Amanita subjunguillea, Amanita virosa, Amanita proxima, Amanita exitialis, Amanita arocheae, Amanita magnivelaris, Amanita bisporigera, Amanita phalloides, Amanita smithiana, and Amanita verna respectively (Zeitlmayr, 1976; Surayot et al., 2021).

The species Amanita vaginata has a pileus 9–10 cm × 3–5 cm in size and brown in color. Their cap shapes are usually convex and have smooth as well as round edges. It has been found that its cap has a fleshy brown color. Hymenophores are not present on the underside. In this mushroom, regular-shaped white colored gills present. It has a brown color stipe with 5 to 7 cm and 2 to 3 cm length and width correspondingly. Light brown color, single welled, round to oval shaped spore present having 7–8 μm × 5–6 μm size (Meena et al., 2020).

Amanita species have various biological activities like antitumor, pesticidal, cytotoxic, antioxidant, anticancer, antibacterial, acetylcholinesterase, esterolytic, antiviral, activity, anti-larvicidal, antifungal, anti-inflammatory properties (Sevindik et al., 2019). Picture of Amanita shown in Figure 8Bh.

Cortinarius is one of the worldwide distributed genera of mushrooms that belongs to the family Cortinariaceae (Cortinarius (Pers.) Gray, 2020). It is supposed to be the major genus of agarics that contains over 2,000 widespread species (Kirk et al., 2008). The species Cortinarius corrugates having a pileus 22–23 cm × 8–9 cm in size and ash colored. This mushroom is ovate in shape with a grooved edge. There are hymenophores beneath the cap whereas on the underside of the cap regular-shaped gills are present. The stipe of the mushroom appears as milky white, on the upper part of the stipe an anal or black ring is present while on the lower part the volva is absent (Meena et al., 2020). Picture of Cortinarius shown in Figure 8Bi.

The mushroom genus Tremella belongs to the family Tremellaceae. All species of Tremella are the parasites of other fungi and mostly produce as anamorphic yeast states when producing Basidiocarps. Tremella is colloquially classed among the gelainous or jelly fungi. Tremella fuciformis and Tremella aurantialba are the two species that are commercially cultivated for food (Zhang et al., 2009). Tremella fuciformis is locally known as silver ear fungus or snow fungus. It is tasteless in nature and has a gelatinous texture (Shu-Ting and Philip, 2004). Tremella fuciformis may have some medicinal important activities like fighting cancer, combating obesity, anti-aging, lowering cholesterol, protecting nerves, and acting as an anti-inflammatory. Picture of Tremella shown in Figure 8Bj.

Rigidoporus is a genus of the fungi that belong to the family Meripilaceae. This fungi forms flattened mycelia of white color which is 1 to 2 mm thick and grows on as well as adheres to the surface of root bark. The species Rigidoporus microporus is 20 cm wide, faintly velvety, leathery in nature. It has a broadly attached shelf as well as imbricate with the substrate. Its color changes from orange to brown or red and later becomes faded (Liyanage, 1997). In the absence of any woody substrates, these rigidoporus grow fast and spread several meters via the soil (Oghenekaro et al., 2014). Rigidoporous have several biological properties like mitogenic activity, anti-hepatitis B surface antigen effect, plasma clotting activity, activation of alternative pathway complement, and tumor suppressive effects (Chang et al., 2011). Picture of Rigidoporus shown in Figure 8Bk.

The genus Grifola belongs to the family Meripilaceae. The species Grifola frondosa is locally called hen of the woods. This mushroom grows in clusters with a grayish to brown cap which appears as curled or spoon-shaped along with wavy margins of 2 to 7 cm wide at the base of the trees, especially oaks. It is 60 cm in size. Each cap bears 1 to 3 pores per mm at the under-surface with the tubes which are rarely deeper than 3 mm. Milky white stipe has a branchy structure and it becomes tough as it matures (Yeh et al., 2011).

Grifola frondosa have some biological activities such as antitumor (Masuda et al., 2006; Cui et al., 2013), anti-inflammation (Han and Cui, 2012; Su et al., 2020), immunomodulation (Adachi et al., 1994), antivirus (Gu et al., 2007; Zhao et al., 2016), antidiabetic (Postemsky and Curvetto, 2015), immune-enhancing, anti-hypertensive, hypoglycemia (Chen and Seviour, 2007) and antioxidation (Yeh et al., 2011). It also contributes to metabolic disorders treatment like non-alcoholic fatty liver disease. It also has potential in the treatment of hyperlipidemia as well as hyperglycemia. Picture of Grifola shown in Figure 8Bl.

The genus Lentinus belongs to the family Polyporaceae and it is mainly spread in the subtropical regions (Kirk et al., 2008). The species of Lentinus have extracellular enzymes, moreover, it acts as wood-decaying basidiomycetes, gregarious on fallen wood of a wide variety of deciduous trees like chestnut, cotton, hornbeam, beech, mulberry, ironwood, shii, oak, maple, chinquapin, sweetgum, and alder in a moist or warm climate (Bisen et al., 2010). Medicinally, Lentinus edodes is used for the diseases such as fungal infection, bronchial inflammation, hyperlipidemia, hepatitis, cancer, depressed immune function, heart disease, infectious disease, flu and cold, environmental allergies, urinary inconsistencies, hypertension, diabetes, etc. (Bisen et al., 2010). Picture of Lentinus shown in Figure 8Cm.

Pleurotus is the genus of gilled mushroom and belongs to the family pleurotaceae. The species Pleurotus ostreatus also known as abalone or tree or oyster mushroom and is an edible mushroom (Chang and Miles, 2004). This mushroom is also used for mycoremediation and attacks and kills nematodes as well as microbes. This mushroom is mostly cultivated on straw and other media. This mushroom has the bitter-sweet aroma of benzaldehyde (Stamets, 2000b). This species of mushroom mainly grows on wood in shelflike clusters. This mushroom is of a larger size, and has white gills that run down a stubby. It has no stem. It has a white to lilac pattern of spores. This Pleurotus ostreatus has an oyster shaped, fan and broad cap spanning 5 to 25 cms. It is tan to dark-brown or white to gray in color. When it is young, its margin is enrolled and then becomes smooth and lobed or wavy. Because of its stipe arrangements, its flesh is firm, white, and of different thicknesses. The gills are white to cream in appearance (Philips and Roger, 2006). This mushroom has some biological effects due to the presence of some nutritional compositions including anti-cholestrolic, anticancer, antiviral, anti-diabetic, antioxidant, eye health, antibacterial and antiarthritic, etc. (Deepalakshmi and Mirunalini, 2014). Picture of Pleurotus shown in Figure 8Cn.

The genus Calocybe is the fungus that belongs to the family Lyophyllaceae. The species Calocybe indica is locally known as a milky-white mushroom that is rich in ascorbic acid, lipids, riboflavin, amino acids, pyridoxine, vitamins, biotin, low fat, nicotinic acid, proteins, minerals (arsenic, zinc, potassium, manganese, calcium, phosphorus, magnesium, iron and sodium), fibers. According to Mandal et al. (2012) this mushroom has antioxidant properties and stimulated immune activation of thymocytes, splenocytes, and macrophages.

It helps in reducing the triglycerides and total plasma cholesterol level and consequently decreases the chance of cardiovascular, artery, and atherosclerosis-related disorders (Alam et al., 2008).

It also possesses biological activities regarding neurodegenerative diseases, anti-carcinogenesis, anti-aging, anti-obesity, cardiovascular disease, anti-infection, preventing physical injury, anti-tumor also helps to reduce the risk of breast cancer (Tsukamoto et al., 2003; Sharma et al., 2013). Picture of Calocybe shown in Figure 8Co.

Huitlacoche is a heterothallic fungus that belongs to the family Ustilaginaceae. This fungus is also known as Mexican truffle, corn mushroom, or corn smut. This mushroom has great importance for the human diet (Valverde et al., 2012). This mushroom contains some bioactive compounds such as proteins, amino acids, glutamic acid, lysine, serine, aspartic acid, glycine, total carbohydrates, arabinose, mannose, galactose, xylose, glucitol, mannitol, glycerol, etc. Out of these, it has been found that xylose, galactose, mannose, and arabinose are present in lower proportions. It also contains heteroglycans, dietary fiber, and homoglycans, etc. (Valverde et al., 2012).

Huitlacoche mushrooms possess antitumoral, antimutagenic, immunomodulating, antiatherogenic, hyperlipidemic, hypo- glycemic, anti-inflammatory as well as various other health-promoting activities (Valdez-Morales et al., 2010). Picture of Huitlacoche shown in Figure 8Cp.

Cordyceps are the fungus that mainly lives on certain caterpillars and are usually found in high mountain regions (Kindzel’skii et al., 1995). The species Cordyceps sinensis comprises cordycepic acid and cordycepin substances. This mushroom has some therapeutic applications such as stabilization of blood sugar metabolism, effects of enhanced utilization of oxygen, and production of ATP. This mushroom protects the organs from kidney, liver, and heart diseases. Cordyceps sinensis also has a sedative effect on the central nervous system of the body (Zhou et al., 2009).

This Cordyceps mushroom also has immunomodulating effects and also possesses anticancer activities, especially skin and lung cancer. It also shrinks the size of tumors (Kindzel’skii et al., 1995). Picture of Cordyceps shown in Figure 8Cq.

Among all the mushrooms, Coriolus versicolor or Trametes versicolor is the best-studied and most potent medicinal mushroom. Coriolus versicolor has been well known for its anti-viral, anti-cancerous properties. This mushroom is mainly found in sub-tropical, tropicalm, and temperate zones and is highly adaptive. It has been found that the mycelial growth of medicinal mushroom Coriolus versicolor can be cultivated in the laboratory (Veena and Pandey, 2012).

Globally, Agaricus medicinal mushroom holds fourth place in commercial mushroom production and is commercially grown in at least 90 countries with more than 4 million tons estimated annual production (Sonnenberg et al., 2011; Royse, 2014). The cultivation of mycelial growth of medicinal mushroom Agaricus sp. can be cultivated in laboratories (Golmwen et al., 2019).

The production of fruiting bodies of Ganoderma sp. is a long-term process that takes several months for the first fruiting body to even appear, depending upon the substrate as well as species. It has also been found that in submerged conditions, the growth of pure culture in liquid culture medium permits the acceleration of the growth due to which biomass can be brought to yield in several days (Asser et al., 2000).

It has been reported that the cultivation of medicinal mushroom Ganoderma sp. is possible in various labs in India. The mycelial of this medicinal mushroom grows well in potato dextrose medium at pH 5 and 25°C, followed by Kirk medium and glucose, malt extract as well as Kirk medium and molasses (Nasreen et al., 2005). Rai, Veena and Pandey, and Mishra and Singh, suggested that currently, medicinal mushrooms are gaining importance in the country (Rai et al., 2005; Veena and Pandey, 2012; Singh et al., 2014).

The cultivation of mycelial growth of medicinal mushroom Hydnum sp. can be cultivated in the laboratory. It has been found that the most suitable carbon and nitrogen sources for the mycelial growth of Hydnum sp. are glucose and mannitol (carbon sources) as well as Ca (NO₃)₂ (nitrogen source) whereas the poorest mycelial growth is found to be in xylose and sucrose (carbon sources) and (NH₄)₂HPO₄ and NH₄NO₃ (nitrogen sources) (Peksen et al., 2013). According to Peksen et al. (2013), Peat and peat (vermiculite mixtures) are the best media that can be used for the production of vegetative inoculum of Hydnum sp. (Peksen et al., 2013).

It has been seen that the culture of medicinal mushroom Coprinus sp. can be cultivated in laboratories (Luo et al., 2004).

The biomass production of medicinal mushroom Morchella sp. can be done in laboratories by using Malt extract agar medium (MEA). It has also been found that the mixture of peat, sawdust, and chestnut crust (domestic waste); peat; peat, rice hulls; peat, wheat; peat, potato crust (domestic waste); peat, sawdust and peat, rice hulls, sawdust can be used as additional material (Eliuz and Goksen, 2017).

The cultivation of mycelial growth of medicinal mushroom Cantharellus sp. can be done in laboratories. It has been found that Murashige and Skoog (MS) medium can be used for the growth along with nitrogen (peptone, beef extract, ammonium citrate, potassium nitrate ammonium nitrate, yeast extract, sodium nitrate, and ammonium sulfate) and carbon (xylose, galactose, glucose, sucrose, and fructose) sources (Deshaware et al., 2021).

The cultivation of mycelial growth of medicinal mushroom Amanita sp. can be done in the laboratory and has also been found that the species in subgenus Lepidella are more easily to isolate and grow in the culture as compared to the species of subgenus Amanitopsis (Zhang et al., 2005).

Globally it has been found that the Cortinarius sp. is one of the largest genera of medicinal mushrooms. Although the genus Cortinarius is very diverse and it is very easy to figure out the species of Cortinarius from other species of mushroom because of the presence of diagnostic macroscopic characteristics (Itoo et al., 2015).

The cultivation of medicinal mushroom Cortinarius sp. can be achieved easily in a laboratory (Matheny et al., 2006).

The mycelial growth of medicinal mushroom Tremella sp. can be cultured in laboratories. It has also been found that this mycelial growth of Tremella sp. can be grown on potato dextrose agar along with cycloheximide (Jang et al., 2014).

The cultivation of mycelial growth of medicinal mushroom Rigidoporus sp. can be achieved in laboratories. It has also been found that the mycelial growth of Rigidoporus sp. can be grown in potato dextrose agar medium and is amended with chloramphenicol and streptomycin sulfate for the suppression of bacterial growth (Go et al., 2021).

The mycelial growth of medicinal mushroom Grifola sp. can be cultivated in labs. It has been demonstrated that the production of mycelial growth of Grifola sp. can occur in a basal nutrient medium (peptone, sucrose, CaCl₂.2H₂O, yeast extract, MnSO₄.H₂O, NH₄NO₃, KNO₃, KPO₄H₂, H₃BO₃, KI, Na₂MoO₄.2H₂O, ZnSO₄.7H₂O, MgSO₄.7H₂O) supplemented with amino acids (inositol, thiamine, pyridoxine, nicotinic acid); vitamins; ascorbic acid (Cicarelli, Argentina, Santa Fé); folic acid (alanine, riboflavin, phenylalanine and tryptophan) (Postemsky and Curvetto, 2015).

The cultivation of mycelial growth of Lentinus sp. works in the laboratory (Mossebo, 2002). It has been found that Lentinus sp. evidenced the growth of mycelia and found the high density in potato dextrose agar whereas a lesser density of mycelia was found in rice bran extract agar (Castillo et al., 2017).

The fruiting bodies of medicinal mushroom pleurotus sp. can be produced in laboratories (Shnyreva et al., 2017). It has been found that the mycelial growth of pleurotus sp. can be done on potato dextrose agar (Silva et al., 2013).

The cultivation of the medicinal mushroom Calocybe sp. can work in laboratories. For the culture of medicinal mushroom Calocybe sp., potato dextrose agar medium can be used (Singh et al., 2017).

The mycelial growth of medicinal mushroom Huitlacoche sp. can be grown in laboratories (Montiel et al., 2015).

The cultivation of the mycelial growth of medicinal mushroom Cordyceps sp. can be grown in culture in laboratories (Ghatnur et al., 2015).