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Licensed Unlicensed Requires Authentication Published by De Gruyter July 19, 2014

l-Carnitine is a calcium chelator: a reason for its useful and toxic effects in biological systems

  • Saleem Ali Banihani EMAIL logo , Mekki Bayachou and Karem Alzoubi


Background: Investigation of the direct link between l-carnitine (LC), a quaternary ammonium compound that facilitates the passage of unsaturated fatty acids into the mitochondrial matrix, and free calcium (Ca2+) is needed to explain a number of varying results obtained from different in vitro and in vivo studies of LC as a supplement.

Methods: The chemical structure of LC, which contains oxygen ligand atoms, prompted to measure its activity as a Ca2+ chelator. The measurement was carried out spectrophotometrically by measuring the reduction in the formation of Ca2+-o-cresolphthalein complexone (Ca-CPC) in the presence of different doses of LC (0.075, 0.75, and 7.5 mM) compared to the control (0.0 mM LC).

Results: The effect of LC was measured as a free entity in solution and when added to human serum. Our results showed a significant decrease (p<0.05) in the average absorbance of Ca-CPC in the presence of LC compared to the control.

Conclusions: In conclusion, LC exhibits a significant Ca2+ chelating activity. As Ca2+ is vital in the biochemical and physiological processes of living cells, LC could be affecting the calcium-dependent biological systems by limiting the levels of free Ca2+. Examples include decelerating the blood clotting process, amplifying the effect of anticoagulants, reducing nitric oxide synthase activity, inhibiting platelet aggregation, and decreasing sperm motility.

Corresponding author: Saleem Ali Banihani, MSc, PhD, Department of Medical Laboratory Sciences, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan, Phone: +962-27201000 Ext. 23874, Fax: +962-2-7201087, E-mail:


This work is supported by both Jordan University of Science and Technology (grant number 20120135) and Cleveland State University.

Conflict of interest statement

Authors’ conflict of interest disclosure: The authors stated that there are no conflicts of interest regarding the publication of this article. Research funding played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

Research funding: None declared.

Employment or leadership: None declared.

Honorarium: None declared.


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Received: 2014-2-19
Accepted: 2014-5-5
Published Online: 2014-7-19
Published in Print: 2015-3-1

©2014 by De Gruyter

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