alkaloid

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al·ka·loid

(ăl′kə-loid′)

Any of various organic compounds that are usually basic and contain at least one nitrogen atom in a heterocyclic ring, occurring chiefly in flowering plants. Many alkaloids, such as nicotine, quinine, cocaine, and morphine, are known for their poisonous or medicinal attributes.

[alkal(i) + -oid.]

al′ka·loi′dal (-loid′l) adj.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

alkaloid

(ˈælkəˌlɔɪd)

(Elements & Compounds) any of a group of nitrogenous basic compounds found in plants, typically insoluble in water and physiologically active. Common examples are morphine, strychnine, quinine, nicotine, and caffeine

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

al•ka•loid

(ˈæl kəˌlɔɪd)
n.

1. any of a large class of bitter-tasting, nitrogen-containing, alkaline ring compounds common in plants and including caffeine, morphine, nicotine, quinine, and strychnine.

adj.

2. resembling an alkali; alkaline.

[1825–35]

al`ka•loi′dal, adj.

al·ka·loid

(ăl′kə-loid′)

Any of a large class of complex organic compounds that contain nitrogen and mostly occur in plants. Alkaloids have a wide range of physiological effects and many uses in medicine, but they can also be toxic. Morphine, quinine, and nicotine are all alkaloids.

The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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Noun

alkaloid - natural bases containing nitrogen found in plants

atropine - a poisonous crystalline alkaloid extracted from the nightshade family; used as an antispasmodic and to dilate the eye pupil; also administered in large amounts as an antidote for organophosphate nerve agents or organophosphate insecticides

hyoscyamine - a poisonous crystalline alkaloid (isometric with atropine but more potent); used to treat excess motility of the gastrointestinal tract

pilocarpine - cholinergic alkaloid used in eyedrops to treat glaucoma

hyoscine, scopolamine - an alkaloid with anticholinergic effects that is used as a sedative and to treat nausea and to dilate the pupils in ophthalmic procedures; "transdermal scopolamine is used to treat motion sickness"; "someone sedated with scopolamine has difficulty lying"

physostigmine - used in treatment of Alzheimer's disease and glaucoma

cinchonine - an alkaloid derivative of the bark of cinchona trees that is used as an antimalarial drug

ephedrine - white odorless powdered or crystalline alkaloid from plants of the genus Ephedra (especially Ephedra sinica) or made synthetically; used as a bronchodilator to treat bronchitis and asthma

ergonovine, Ergotrate Maleate - an alkaloid derived from ergot (trade name Ergotrate Maleate) that is less toxic than ergot; induces muscular contraction of the uterus and is administered after childbirth or abortion

ergotamine - an alkaloid derived from ergot that is less toxic than ergot; causes constriction of blood vessels and is used to treat migraine

pseudoephedrine - poisonous crystalline alkaloid occurring with ephedrine and isomorphic with it

nicotine - an alkaloid poison that occurs in tobacco; used in medicine and as an insecticide

strychnine - an alkaloid plant toxin extracted chiefly from nux vomica; formerly used as a stimulant

brucine - a bitter alkaloid poison resembling strychnine and extracted from nux vomica

betaine - a sweet tasting alkaloid that occurs in sugar beets

organic compound - any compound of carbon and another element or a radical

caffein, caffeine - a bitter alkaloid found in coffee and tea that is responsible for their stimulating effects

rauwolfia - any of several alkaloids extracted from the shrub Rauwolfia serpentina

curare, tubocurarine - a toxic alkaloid found in certain tropical South American trees that is a powerful relaxant for striated muscles; "curare acts by blocking cholinergic transmission at the myoneural junction"

Translations

alkaloid

alkaloid

alkaloid

[ˈælkəlɔɪd]

A. ADJ → alcaloideo

B. N → alcaloide m

Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

alkaloid

n → Alkaloid nt

Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

al·ka·loid

n. alcaloide, grupo de sustancias orgánicas básicas de origen vegetal.

References in classic literature ?

"Death from some powerful vegetable alkaloid," I answered,--"some strychnine-like substance which would produce tetanus."

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I could imagine his giving a friend a little pinch of the latest vegetable alkaloid, not out of malevolence, you understand, but simply out of a spirit of inquiry in order to have an accurate idea of the effects.

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Alkaloid from fire ant venom: identification and synthesis.

Whole body solvent soak gives representative venom alkaloid profile from Solenopsis invicta (Hymenoptera: Formicidae) workers

The purpose of this research is to prove the immunomodulatory activity of alkaloid sambiloto against a specific immune response i.e., interferon [gamma] (IFN[gamma]) and T-helper cells ([CD4.sup.+]) after and before being infected with Salmonella typhimurium.

Alkaloid immunomodulatory effects of sambiloto (andrographis paniculate l.) on the response of gamma interferon and t helper cell ([cd4.sup.+])

Implications: The Committee on Herbal Medicinal Products of the European Medicines Agency recommended in 2014 that pyrrolizidine alkaloid intake from herbal medicinal products be limited to 0.35 microgram/day, and several European countries are now transitioning towards the adoption of this limit.

Pyrrolizidine alkaloids in herbal medicines--re-emergence of an old threat?

Interestingly, the TOF mass analyzer enabled us to detect the molecule ions ([M.sup.+]) of each alkaloid in itself and generate their molecular formulae with errors lower than 10 ppm (Table 1 and Table S1).

Alkaloids Profiling of Fumaria capreolata by Analytical Platforms Based on the Hyphenation of Gas Chromatography and Liquid Chromatography with Quadrupole-Time-of-Flight Mass Spectrometry

Previously, crude alkaloid extract from Mitragyna speciosa (MS) Korth was found to produce antidepressant activities.

Effects of an alkaloid-rich extract from Mitragyna speciosa leaves and fluoxetine on sleep profiles, EEG spectral frequency and ethanol withdrawal symptoms in rats

Alkaloid achieved positive financial results from January to March 2018, according to its latest unaudited financial statements.

ALKALOID INCREASES EXPORT, PROFIT, NUMBER OF EMPLOYEES

The alkaloid data were compared for interand intra-species differences and for interspecies differences between years using analysis of variance (ANOVA).

A survey of Senecio spp. affecting livestock in Uruguay and their associated pyrrolizidine alkaloid content/Senecio spp. Afetando a pecuaria no Uruguai e sua associacao com alcaloides pirrolizidinicos

Inhibition of diaphorase activity of PfFNR was measured in the reaction of Scheme 1 as described above, by the additions of each alkaloid at 100 ppm, NADPH at 100 uM, and 5 nM FNR.

Inhibitory Activity and Docking Analysis of Antimalarial Agents from Stemona sp. toward Ferredoxin-NADP+ Reductase from Malaria Parasites

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