title: Further aspects of ochratoxin A-cation interactions: complex formation with zinc ions and a novel analytical application of ochratoxin A-magnesium interaction in the HPLC-FLD system.
abstract: Ochratoxin A (OTA) is a mycotoxin produced by different Aspergillus and Penicillium species. Since its mechanism of action is not fully understood yet, it is important to gain further insight into different interactions of OTA at the molecular level. OTA is found worldwide in many foods and drinks. Moreover, it can also be detected in human and animal tissues and body fluids, as well. Therefore, the development of highly sensitive quantitative methods for the determination of OTA is of utmost importance. OTA most likely forms complexes with divalent cations, both in cells and body fluids. In the present study, the OTA-zinc interaction was investigated and compared to OTA-magnesium complex formation using fluorescence spectroscopy and molecular modeling. Our results show that zinc(II) ion forms a two-fold higher stable complex with OTA than magnesium(II) ion. In addition, based on the enhanced fluorescence emission of OTA in its magnesium-bound form, a novel RP-HPLC-fluorescence detector (FLD) method was also established. Our results highlight that the application of magnesium chloride in alkaline eluents results in an approximately two-fold increase in sensitivity using the HPLC-FLD technique.
authors.affiliation: Institute of Laboratory Medicine, University of Pécs, Pécs H-7624, Hungary. poor.miklos@pte.hu.
authors.forename: Miklós
authors.initials: M
authors.lastname: Poór
authors.affiliation: Department of Pharmaceutical Chemistry, University of Pécs, Pécs H-7624, Hungary. monika.kuzma@aok.pte.hu.
authors.forename: Mónika
authors.initials: M
authors.lastname: Kuzma
authors.affiliation: Department of General and Physical Chemistry, University of Pécs, Pécs H-7624, Hungary. gmatisz@gamma.ttk.pte.hu.
authors.forename: Gergely
authors.initials: G
authors.lastname: Matisz
authors.affiliation: Department of General and Physical Chemistry, University of Pécs, Pécs H-7624, Hungary. liyincumt@gmail.com.
authors.forename: Yin
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical Chemistry, University of Pécs, Pécs H-7624, Hungary. pal.perjesi@aok.pte.hu.
authors.forename: Pál
authors.initials: P
authors.lastname: Perjési
authors.affiliation: Department of General and Physical Chemistry, University of Pécs, Pécs H-7624, Hungary. kunsagi@gamma.ttk.pte.hu.
authors.forename: Sándor
authors.initials: S
authors.lastname: Kunsági-Máté
authors.affiliation: Institute of Laboratory Medicine, University of Pécs, Pécs H-7624, Hungary. koszegit@freemail.hu.
authors.forename: Tamás
authors.initials: T
authors.lastname: Kőszegi
mesh_terms: D001665:Binding Sites; D002712:Chlorides / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D006863:Hydrogen-Ion Concentration; D015636:Magnesium Chloride / Q000737:chemistry*; D008958:Models, Molecular; D009793:Ochratoxins / Q000032:analysis / Q000737:chemistry*; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence; D013816:Thermodynamics; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D002712:Chlorides; D009793:Ochratoxins; D017967:Zinc Compounds; D015636:Magnesium Chloride; C025589:ochratoxin A; C016837:zinc chloride
references.citation: J Res Med Sci. 2013 Feb;18(2):144-57
references.pmid: 23914218
references.citation: Biochem Pharmacol. 1988 Dec 1;37(23):4469-77
references.pmid: 3202889
references.citation: J Chem Theory Comput. 2009 Oct 13;5(10):2619-28
references.pmid: 26631777
references.citation: Anal Chim Acta. 2009 Jan 26;632(2):168-80
references.pmid: 19110091
references.citation: J Chromatogr A. 1998 Jul 31;815(1):75-92
references.pmid: 9718709
references.citation: Proc Nutr Soc. 2000 Nov;59(4):541-52
references.pmid: 11115789
references.citation: Eur J Epidemiol. 1995 Apr;11(2):235-8
references.pmid: 7672083
references.citation: J Chromatogr A. 2004 Jan 23;1024(1-2):275-9
references.pmid: 14753729
references.citation: J Trace Elem Med Biol. 2012 Jun;26(2-3):66-9
references.pmid: 22664333
references.citation: Arch Toxicol. 2000 Nov;74(9):499-510
references.pmid: 11131029
references.citation: J Chem Soc Perkin 1. 1965 Dec;:7083-8
references.pmid: 5892024
references.citation: Adv Exp Med Biol. 2002;504:117-34
references.pmid: 11922081
references.citation: J Chromatogr B Analyt Technol Biomed Life Sci. 2007 Aug 15;855(2):242-8
references.pmid: 17560179
references.citation: Biochem Pharmacol. 1990 Sep 15;40(6):1183-91
references.pmid: 2119584
references.citation: J Chem Phys. 2010 May 21;132(19):194502
references.pmid: 20499974
references.citation: Int J Biol Macromol. 2012 Oct;51(3):279-83
references.pmid: 22634515
references.citation: Biochim Biophys Acta. 2006 Jul;1763(7):711-22
references.pmid: 16675045
references.citation: Environ Health Perspect. 1998 Nov;106(11):689-700
references.pmid: 9799184
references.citation: Toxicol Appl Pharmacol. 2013 Apr 15;268(2):123-31
references.pmid: 23391613
references.citation: Toxins (Basel). 2012 Apr;4(4):244-66
references.pmid: 22606375
references.citation: Am J Clin Nutr. 1990 Feb;51(2):225-7
references.pmid: 2407097
references.citation: Chem Biol Interact. 2006 Jan 5;159(1):18-46
references.pmid: 16293235
references.citation: Luminescence. 2013 Sep-Oct;28(5):726-33
references.pmid: 22987806
references.citation: J Chem Phys. 2010 Apr 21;132(15):154104
references.pmid: 20423165
references.citation: J Agric Food Chem. 2002 Jan 16;50(2):243-7
references.pmid: 11782189
references.citation: J Comput Chem. 2011 May;32(7):1456-65
references.pmid: 21370243
references.citation: Toxicol In Vitro. 2009 Dec;23(8):1516-21
references.pmid: 19720134
references.citation: Adv Nutr. 2012 Nov 01;3(6):772-82
references.pmid: 23153731
references.citation: J Appl Toxicol. 1989 Apr;9(2):91-6
references.pmid: 2715571
references.citation: J Phys Chem A. 2009 Oct 29;113(43):11856-65
references.pmid: 19639948
references.citation: J Chem Inf Model. 2007 May-Jun;47(3):1045-52
references.pmid: 17428029
references.citation: J Photochem Photobiol B. 2013 Jul 5;124:20-6
references.pmid: 23648796
references.citation: Cancer Sci. 2008 Aug;99(8):1515-22
references.pmid: 18754861