| 释义 |
yeast
yeast Y0012700 (yēst)n.1. a. Any of various unicellular fungi of the genus Saccharomyces, especially S. cerevisiae, reproducing asexually by budding or sexually through the production of ascospores and capable of fermenting carbohydrates.b. Any of numerous fungi that exhibit a one-celled growth form and reproduce by budding, including certain candidas that can cause infections in humans.2. Froth consisting of yeast cells together with the carbon dioxide they produce in the process of fermentation, present in or added to fruit juices and other substances in the production of alcoholic beverages.3. A powdered or compressed commercial preparation of yeast cells, used chiefly as a leavening agent or as a dietary supplement.4. An agent of ferment or activity: political agitators who are the yeast of revolution.
[Middle English yeest, from Old English gist; see yes- in Indo-European roots.]yeast (jiːst) n1. (Plants) any of various single-celled ascomycetous fungi of the genus Saccharomyces and related genera, which reproduce by budding and are able to ferment sugars: a rich source of vitamins of the B complex2. (Biology) any yeastlike fungus, esp of the genus Candida, which can cause thrush in areas infected with it3. (Cookery) a commercial preparation containing yeast cells and inert material such as meal, used in raising dough for bread or for fermenting beer, whisky, etc. See also brewer's yeast4. (Pharmacology) a preparation containing yeast cells, used to treat diseases caused by vitamin B deficiency5. (Brewing) froth or foam, esp on beervb (intr) to froth or foam[Old English giest; related to Old Norse jostr, Old High German jesan, Swedish esa, Norwegian asa, Sanskrit yasati] ˈyeastless adj ˈyeastˌlike adjyeast (yist)
n. 1. any of various small, single-celled fungi of the phylum Ascomycota that reproduce by fission or budding, the daughter cells often remaining attached, and that are capable of fermenting carbohydrates into alcohol and carbon dioxide. 2. any of several yeasts of the genus Saccharomyces, used in brewing alcoholic beverages, as a leaven in baking breads, and in pharmacology as a source of vitamins and proteins. 3. something that causes ferment or agitation. v.i. 4. to ferment. 5. to froth. [before 1000; Middle English ye(e)st, Old English gist, gyst, c. Middle Dutch ghist, Middle High German gist, Old Norse jǫstr; akin to Greek zestós boiled, Skt yásati (it) boils] yeast′less, adj. yeast′like`, adj. yeast (yēst)1. Any of various one-celled fungi that can cause the fermentation of carbohydrates, producing carbon dioxide and alcohol.2. A commercial preparation in either compressed or powdered form that contains yeast cells. It is used to make bread dough rise.yeast
Past participle: yeasted
Gerund: yeasting
| Present |
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| I yeast | | you yeast | | he/she/it yeasts | | we yeast | | you yeast | | they yeast |
| Preterite |
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| I yeasted | | you yeasted | | he/she/it yeasted | | we yeasted | | you yeasted | | they yeasted |
| Present Continuous |
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| I am yeasting | | you are yeasting | | he/she/it is yeasting | | we are yeasting | | you are yeasting | | they are yeasting |
| Present Perfect |
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| I have yeasted | | you have yeasted | | he/she/it has yeasted | | we have yeasted | | you have yeasted | | they have yeasted |
| Past Continuous |
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| I was yeasting | | you were yeasting | | he/she/it was yeasting | | we were yeasting | | you were yeasting | | they were yeasting |
| Past Perfect |
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| I had yeasted | | you had yeasted | | he/she/it had yeasted | | we had yeasted | | you had yeasted | | they had yeasted |
| Future |
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| I will yeast | | you will yeast | | he/she/it will yeast | | we will yeast | | you will yeast | | they will yeast |
| Future Perfect |
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| I will have yeasted | | you will have yeasted | | he/she/it will have yeasted | | we will have yeasted | | you will have yeasted | | they will have yeasted |
| Future Continuous |
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| I will be yeasting | | you will be yeasting | | he/she/it will be yeasting | | we will be yeasting | | you will be yeasting | | they will be yeasting |
| Present Perfect Continuous |
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| I have been yeasting | | you have been yeasting | | he/she/it has been yeasting | | we have been yeasting | | you have been yeasting | | they have been yeasting |
| Future Perfect Continuous |
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| I will have been yeasting | | you will have been yeasting | | he/she/it will have been yeasting | | we will have been yeasting | | you will have been yeasting | | they will have been yeasting |
| Past Perfect Continuous |
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| I had been yeasting | | you had been yeasting | | he/she/it had been yeasting | | we had been yeasting | | you had been yeasting | | they had been yeasting |
| Conditional |
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| I would yeast | | you would yeast | | he/she/it would yeast | | we would yeast | | you would yeast | | they would yeast |
| Past Conditional |
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| I would have yeasted | | you would have yeasted | | he/she/it would have yeasted | | we would have yeasted | | you would have yeasted | | they would have yeasted |
yeastFungus cells used in raising dough for bread and for fermenting alcohol.Thesaurus| Noun | 1. |  yeast - a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskeybarmyeast cake - small cake of compressed moist yeastbrewer's yeast - yeast used in fermenting beerleaven, leavening - a substance used to produce fermentation in dough or a liquidmother - a stringy slimy substance consisting of yeast cells and bacteria; forms during fermentation and is added to cider or wine to produce vinegar | | 2. | yeast - any of various single-celled fungi that reproduce asexually by budding or divisionfungus - an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytiaEndomycetales, order Endomycetales - fungi having a zygote or a single cell developing directly into an ascusbaker's yeast, Saccharomyces cerevisiae, brewer's yeast - used as a leaven in baking and brewingSaccharomyces ellipsoides, wine-maker's yeast - used in making wine |
yeastnoun1. A mass of bubbles in or on the surface of a liquid:foam, froth, head, lather, spume, suds.2. An agent that stimulates or precipitates a reaction, development, or change:catalyst, ferment, leaven, leavening.verbTo form or cause to form foam:bubble, cream, effervesce, fizz, foam, froth, lather, spume, suds.Translationsyeast (jiːst) noun a substance which causes fermentation, used in making beer, bread etc. 酵母 酵母yeast
yeast, name applied specifically to a certain group of microscopic fungiFungi
, kingdom of heterotrophic single-celled, multinucleated, or multicellular organisms, including yeasts, molds, and mushrooms. The organisms live as parasites, symbionts, or saprobes (see saprophyte).
..... Click the link for more information. and to commercial products consisting of masses of dried yeast cells or of yeast mixed with a starchy material and pressed into yeast cakes. Although a number of fungi are sometimes called yeasts, the true yeasts are unicellular, consist of oval or round cells, and reproduce chiefly by budding. Under certain conditions some yeast cells secrete a thickened wall, and the cytoplasm of the single cell within divides to form four or eight cells, or spores, known as ascospores, which emerge when the wall ruptures. In a few species two cells fuse before undergoing spore formation. There are about 500 species in all. Yeasts, especially those of the genus Saccharomyces, have long been of commercial importance because they are the chief agents in alcoholic fermentationfermentation,
process by which the living cell is able to obtain energy through the breakdown of glucose and other simple sugar molecules without requiring oxygen. Fermentation is achieved by somewhat different chemical sequences in different species of organisms.
..... Click the link for more information. . Because of this they are essential to the making of beerbeer,
alcoholic beverage made by brewing and fermenting cereals, especially malted barley, usually with the addition of hops as a flavoring agent and stabilizer. One of the oldest of alcoholic beverages (there is archaeological evidence dating to c.3000 B.C.
..... Click the link for more information. , winewine,
alcoholic beverage made by the fermentation of the juice of the grape. Wine is so ancient that its origin is unknown. The earliest archaeological evidence of winemaking dates to 8,000 years ago, and wine is mentioned in early Egyptian inscriptions and in the literature of
..... Click the link for more information. , and other alcoholic beverages and industrial alcohol. Wild yeasts, those found in nature and probably carried by insects from the soil to fruits, are frequently active in the fermentation process. In breadmaking the yeasts act upon the carbohydrates in the dough, forming carbon dioxide and ethyl alcohol, which are driven off in the baking process; the escaping carbon dioxide causes the bread to rise. Since early times yeast has been used in treating various ailments; brewer's yeast has a high content of thiamine and other vitamins of the B-complex group. Yeasts are classified in the kingdom Fungi, phyla (divisions) Ascomycota and Basidiomycota. Yeast A collective name for those fungi which possess, under normal conditions of growth, a vegetative body (thallus) consisting, at least in part, of simple, single cells. The cells making up the thallus occur in pairs, in groups of three, or in straight or branched chains consisting of as many as 12 or more cells. Vegetative reproduction is characterized by budding or fission. Sexual reproduction also occurs in yeast, and is differentiated from that of other fungi by sexual states that are not enclosed in a fruiting body. Yeasts are a phylogenetically diverse group of organisms that occur in two divisions of fungi (Ascomycotina and Basidiomycotina) and 100 genera. The 700 or more species that have been described possibly represent only 1% of the species in nature, so the majority of the yeasts have yet to be discovered. Yeast plays a large part in industrial fermentation processes such as the production of industrial enzymes and chemicals, food products, industrial ethanol, and malt beverage and wine; in diseases of humans, animals and plants; in food spoilage; and as a model of molecular genetics. See Genetic engineering, Medical mycology The shape and size of the individual cells of some species vary slightly, but in other species the cell morphology is extremely heterogeneous. The shape of yeast cells may be spherical, globose, ellipsoidal, elongate to cylindrical with rounded ends, more or less rectangular, pear-shaped, apiculate or lemon-shaped, ogival or pointed at one end, or tetrahedral. The diameter of a spherical cell may vary from 2 to 10 micrometers. The length of cylindrical cells is often 20–30 μm and, in some cases, even greater. The asexual multiplication of yeast cells occurs by a budding process, by the formation of cross walls or fission, and sometimes by a combination of these two processes. Yeast buds are sometimes called blastospores or blastoconidia. When yeast reproduces by a fission mechanism, the resulting cells are termed arthrospores or arthroconidia. Yeasts are categorized into two groups, based on their methods of sexual reproduction: the ascomycetous (Division Ascomycotina) and basidiomycetous (Division Basidiomycotina) yeasts. The sexual spores of the ascomycetous yeasts are termed ascospores, which are formed in simple structures, often a vegetative cell. Such asci are called naked asci because of the absence of an ascocarp, which is a more complex fruiting body found in the higher Ascomycetes. If the vegetative cells are diploid, a cell may transform directly into an ascus after the 2n nucleus undergoes a reduction or meiotic division. See Ascomycota Certain yeasts have been shown to be heterothallic; that is, sporulation occurs when strains of opposite mating type (usually indicated by “a” and α) are mixed on sporulation media. However, some strains may be homothallic (self-fertile), and reduction division and karyogamy (fusion of two haploid nuclei) take place during formation of the sexual spore. Yeasts that produce sporogenous cells represent the teleomorphic form of the life cycle. In cases, in which sexual cycles are unknown, the yeast represents the asexual or anamorphic form. A species of yeast may be originally discovered in the anamorphic form and named accordingly; subsequently, the sexual state may be found and a name applied to represent the teleomorph. Consequently, the anamorphic and teleomorphic names will differ. Basidiospores and teliospores are the sexual spores that are produced in the three classes of basidiomycetous yeasts: Urediniomycetes, Hymenomycetes, and Ustilaginomycetes. Sexual reproduction and life cycle in these yeasts is typical of other basidiomycetes in that it can include both unifactorial (bipolar) and bifactorial (tetrapolar) mating systems. See Basidiomycota Some yeasts have the ability to carry out an alcoholic fermentation. Other yeasts lack this property. In addition to the fermentative type of metabolism, fermentative yeasts as a rule have a respiratory type of metabolism, whereas nonfermentative yeasts have only a respiratory, or oxidative, metabolism. Both reactions produce energy, with respiration producing by far the most, which is used in part for synthetic reactions, such as assimilation and growth. Part is lost as heat. In addition, small or sometimes large amounts of by-products are formed, including organic acids, esters, aldehydes, glycerol, and higher alcohols. When a fermenting yeast culture is aerated, fermentation is suppressed and respiration increases. This phenomenon is called the Pasteur effect. See Fermentation Yeasts are ubiquitous in nature. They exist on plants and animals; in waters, sediments, and soils; and in terrestrial, aquatic, and marine habitats. Yeasts require oxygen for growth and reproduction; therefore they do not inhabit anaerobic environments such as anoxic sediments. Many species have highly specific habitats, whereas others are found on a variety of substrates in nature. yeast[yēst] (mycology) A collective name for those fungi which possess, under normal conditions of growth, a vegetative body (thallus) consisting, at least in part, of simple, individual cells. yeast1. any of various single-celled ascomycetous fungi of the genus Saccharomyces and related genera, which reproduce by budding and are able to ferment sugars: a rich source of vitamins of the B complex 2. any yeastlike fungus, esp of the genus Candida, which can cause thrush in areas infected with it 3. a preparation containing yeast cells, used to treat diseases caused by vitamin B deficiency yeast
yeast [yēst] any of various unicellular, nucleated, usually rounded fungi that reproduce by budding; some are fermenters of carbohydrates, and a few are pathogenic for humans.brewer's yeast Saccharomyces cerevisiae, used in brewing beer, making alcoholic liquors, and baking bread.dried yeast dried cells of any suitable strain of Saccharomyces cerevisiae, usually a by-product of the brewing industry; used as a natural source of protein and B-complex vitamins.yeast (yēst), A general term denoting true fungi of the family Saccharomycetaceae that are widely distributed in substrates that contain sugars (such as fruits), and in soil, animal excreta, the vegetative parts of plants, etc. Because of their ability to ferment carbohydrates, some yeasts are important to the brewing and baking industries. [A.S. gyst] yeast (yēst)n.1. a. Any of various unicellular fungi of the genus Saccharomyces, especially S. cerevisiae, reproducing asexually by budding or sexually through the production of ascospores and capable of fermenting carbohydrates.b. Any of numerous fungi that exhibit a one-celled growth form and reproduce by budding, including certain candidas that can cause infections in humans.2. Froth consisting of yeast cells together with the carbon dioxide they produce in the process of fermentation, present in or added to fruit juices and other substances in the production of alcoholic beverages.3. A powdered or compressed commercial preparation of yeast cells, used chiefly as a leavening agent or as a dietary supplement.yeast A unicellular spherical-to-oval 3–5 µm budding fungus that reproduces both sexually and asexually, primarily by budding–some by binary fission which, when adherent in end-to-end rows are termed pseudohyphae; most fungi are saprobes; many are used in commercial fermentation of foods and beverages; 7 genera–class Deuteromycetes–Imperfect Fungi–are human pathogens: Candida, Crytococcus, Geotrichum, Pityrosporum, Rhodotorula, Torulopsis, Trichosporon. See Candida, YAC cloning. yeast (yēst) A general term denoting true fungi of the family Saccharomycetaceae that are widely distributed in substrates that contain sugars (such as fruits), and in soil, animal excreta,and the vegetative parts of plants. Because of their ability to ferment carbohydrates, some yeasts are important to the brewing and baking industries. [A.S. gyst]yeast (yest)  BUDDING YEAST: (×400)1. Any of several unicellular fungi of the genera Saccharomyces or Candida, which reproduce by budding. They are capable of fermenting carbohydrates. Yeasts, esp. Candida albicans, may cause systemic infections as well as vaginitis and oral thrush. Yeast infections are frequently present in patients with malignant lymphomas, poorly controlled diabetes mellitus, AIDS, or other conditions causing immunocompromise. Synonym: Saccharomyces See: illustration; Candida; candidiasis; fungi2. A commercial product composed of meal impregnated with living fungi, used, for example, in fermenting beer and ale and baking bread. BUDDING YEASTbrewer's yeastYeast obtained during the brewing of beer. It is a rich source of folic acid and chromium. illustrationdried yeastDried yeast cells from strains of Saccharomyces cerevisiae. It is used as a source of proteins and vitamins, esp. B complex. yeast a collective name for those unicellular fungi, typically in the ASCOMYCOTA, of economic importance in the brewing and bread-making industries (see SACCHAROMYCES). Yeasts secrete ENZYMES that convert sugars into alcohol and carbon dioxide (see ALCOHOLIC FERMENTATION) and it is the CO2 which causes bread to ‘rise’.yeast (yēst) A general term denoting true fungi that are widely distributed in substrates that contain sugars (e.g., fruits), and in soil, animal excreta, and vegetative parts of plants. Because of their ability to ferment carbohydrates, some yeasts are important in brewing and baking industries. [A.S. gyst]Patient discussion about yeastQ. Yeast infection in bloodstream How to get rid of yeast infection systemically.A. there are several treatments and medications against systemic fungal infections, yeasts included. but in order to get treated you have to go through a proper diagnosis and a Dr. should check what kind of fungus you are having and prescribe the medication that fits it. me throwing all sort of medication names won't give you anything. this has to be checked out with a blood test and a culture. Q. yeast infection A. Sorry, I posted this in the questions section by mistake - I thought I was doing an information search. I only just joined and I'm still getting used to this wonderful site. Many thanks for your quick response. More discussions about yeastyeast
Related to yeast: Nutritional yeastSynonyms for yeastnoun a mass of bubbles in or on the surface of a liquidSynonyms- foam
- froth
- head
- lather
- spume
- suds
noun an agent that stimulates or precipitates a reaction, development, or changeSynonyms- catalyst
- ferment
- leaven
- leavening
verb to form or cause to form foamSynonyms- bubble
- cream
- effervesce
- fizz
- foam
- froth
- lather
- spume
- suds
Synonyms for yeastnoun a commercial leavening agent containing yeast cellsSynonymsRelated Words- yeast cake
- brewer's yeast
- leaven
- leavening
- mother
noun any of various single-celled fungi that reproduce asexually by budding or divisionRelated Words- fungus
- Endomycetales
- order Endomycetales
- baker's yeast
- Saccharomyces cerevisiae
- brewer's yeast
- Saccharomyces ellipsoides
- wine-maker's yeast
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