Medicinal fungi are fungi that contain metabolites or can be induced to produce metabolites through biotechnology to develop prescription drugs. Compounds successfully developed into drugs or under research include antibiotics, anti-cancer drugs, cholesterol and ergosterol synthesis inhibitors, psychotropic drugs, immunosuppressants and fungicides. History Although fungi products have long been used in traditional medicine, the ability to identify beneficial properties and then extract the active ingredient started with the discovery of penicillin by Alexander Fleming in 1928. Since that time, many potential antibiotics were discovered and the potential for various fungi to synthesize biologically active molecules useful in various clinical therapies has been under research. Pharmacological research identified antifungal, antiviral, and antiprotozoan compounds from fungi. Ganoderma lucidum, known in Chinese as líng zhī ("spirit plant"), and in Japanese as mannentake ("10,000-year mushroom"), has been well studied. Another species of genus Ganoderma, G. applanatum, remains under basic research. Inonotus obliquus was used in Russia as early as the 16th century, and it featured in Alexandr Solzhenitsyn's 1967 novel Cancer Ward. Research and drug development Cancer Paclitaxel is synthesised using Penicillium raistrickii and plant cell fermentation. Fungi can synthesize other mitotic inhibitors including vinblastine, vincristine, podophyllotoxin, griseofulvin, aurantiamine, oxaline, and neoxaline. 11,11'-Dideoxyverticillin A, an isolate of marine Penicillium, was used to create dozens of semi-synthetic, candidate anticancer compounds. 11,11'-Dideoxyverticillin A, andrastin A, barceloneic acid A, and barceloneic acid B, are farnesyl transferase inhibitors that can be made by Penicillium. 3-O-Methylfunicone, anicequol, duclauxin, and rubratoxin B, are anticancer/cytotoxic metabolites of Penicillium. Penicillium is a potential source of the leukemia medicine asparaginase. Some countries have approved beta-glucan fungal extracts lentinan, polysaccharide-K, and polysaccharide peptide as immunologic adjuvants. Evidence suggests this use as effective in prolonging and improving the quality of life for patients with certain cancers, although the Memorial Sloan-Kettering Cancer Center observes that "well designed, large scale studies are needed to establish the role of lentinan as a useful adjunct to cancer treatment". According to Cancer Research UK, "there is currently no evidence that any type of mushroom or mushroom extract can prevent or cure cancer". Fungal metabolites such as ergosterol, clavilactones, and triterpenoids are efficient Cdk inhibitors that lead to G1/S or G2/M arrest of cancer cells. Other metabolites, such as panepoxydone, are inhibitors of NF-κB. Fucose and mannose fragments of fungal cell wall are antagonists of VEGF-receptors. Antibacterial agents (antibiotics) Alexander Fleming led the way to the beta-lactam antibiotics with the Penicillium