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C28H44O A crystalline, water-insoluble, unsaturated sterol found in ergot, yeast, and other fungi, and which may be converted to vitamin D2 on irradiation with ultraviolet light or activation with electrons. Also known as ergosterin.



(also provitamin D2), C28H44O, a natural compound of the sterol group with the structural formula

Ergosterol is formed in yeast, molds, and other fungi. The crystals have a melting point of 165°C. Insoluble in water, they are soluble in organic solvents. Ergosterol is optically active, with a specific rotation of [α]D = –129°. The compound is highly reactive because of conjugate double bonds in the B ring of the system. Like cholesterol, it can form molecular complexes and inclusion complexes in cells. When irradiated with ultraviolet light, the B ring breaks, and ergosterol forms precalciferol, which is easily isomerized by heating to yield vitamin D2 (ergocalciferol).

In the pharmaceutical industry, ergosterol is used in the preparation of vitamin D2 and the hormone progesterone. Ergosterol is extracted from the alkaline hydrolyzates of baker’s yeast or the mycelial by-products from the manufacture of antibiotics.

References in periodicals archive ?
Ergosterol was determined using an Agilent model 5973 quadrupole mass spectrometer (Agilent Technologies, Inc.
Testing the association between residential fungus and health using ergosterol measures and cough recordings.
Terbinafine inhibits ergosterol biosynthesis through inhibition of the enzyme squalene oxidase (rather than p450 and lanosterol-converting enzymes).
The antifungal effect of azoles is due to inhibition of sterol 14[alpha]-demethylase in fungi and yeast, thereby blocking the biosynthesis of ergosterol (Espinel-Ingroff 1997; Georgopapadakou 1998; Joseph-Horne and Hollomon 1997).
Ergosterol peroxide (EP), 5[alpha], 8[alpha]-epidioxy-22E-ergosta-6, 22-dien-3[beta]-ol is a major bioactive compound isolated from the insect-body portions of Cordyceps cicadae Shing (C.
The antifungal drugs currently available for the treatment of invasive mycoses can be divided into four different classes on the basis of their mechanisms of action: (1) Alteration of membrane function (amphotericin B); (2) inhibition of DNA or RNA synthesis (flucytosine); (3) inhibition of ergosterol biosynthesis (azoles [fluconazole, itraconazole, and the newer agents voriconazole, posaconazole, and ravuconazole]); and (4) inhibition of glucan synthesis (echinocandins [caspofungin, micafungin, and anidulafungin]).
Ravuconazole demonstrates antifungal activity by inhibiting ergosterol biosynthesis, a membrane component of fungal cells.
Xuezhikang contains the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor lovastatin, flavonoids, ergosterol amino acids, unsaturated fatty acids, trace elements, and other effective components.
Going into the contents of the material, the scientists did a chemical analysis to find ergosterol, an organic molecule that could be left behind from baking, the scientists wrote, although it could also be an indicator of brewing or agriculture.
AMB, which acts by binding to ergosterol in the cellular membrane and increasing cell permeability, is an antifungal agent with a considerably broad spectrum.
Its fungistatic action is attributed to its inhibitory action on 14[alpha]-demethylase, which converts lanosterol to ergosterol and is required in fungal cell wall synthesis.