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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.

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.


relating to alkaloids
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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Adj.1.alkaloidal - pertaining to or consisting of alkaloids
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References in periodicals archive ?
In the present study, plant material was defatted with petroleum ether and then its alkaloidal contents were further reduced by extracting the residue with chloroform, in which alkaloids were soluble.
In the present study, we aimed to investigate the alkaloidal composition of G gracilis collected from a different localisation considering the possible differences depending on climatic and geographical factors.
The alkaloidal fraction include indazole-type alkaloids, such as nigellidine and nigelanoid (13,14), and dolabellane-type diterpene alkaloids, such as nigellamines (15,16), and various triterpene glycosides (17), such as [alpha]-hederin (18), and steroidal glucoside (19), have also been isolated from the seeds.
Siddiqui, A reinvestigation of the alkaloidal constituents of Peganumharmala,Pak.
Piperine (1-piperoyl piperidine), an alkaloidal component of both Piper nigrum Linn.
Koumine (PubChem CID: 91895267), one of the main alkaloidal constituents of Gelsemium elegans Benth., has attracted an increasing amount of attention from researchers owing to its novel hexacyclic cage structure and multiple biological effects [14].
No significant differences in relative percentages of alkaloidal peaks were detected between the different extraction methods (Table 1).
Following extraction and isolation of the alkaloidal extract of the plant material, the team performed fractionation by thin-layer chromatography on an acid alumina column to yield five fractions.
Futrell et al., "Cerebrovascular complications of the use of the 'crack' form of alkaloidal cocaine," The New England Journal of Medicine, vol.