Mycotoxins in herbal teas marketed in Latvia and dietary exposure assessment

The occurrence of 12 mycotoxins has been analysed by liquid chromatography - time of flight mass spectrometry in the batch of 60 herbal teas purchased from drugstores in Latvia. Among the dry tea samples, 90% were positive for one to eight mycotoxins. Enniatin B and deoxynivalenol (DON) were the most frequently detected mycotoxins in 55% and 45% of the samples, respectively. DON reached the highest level, from 129 µg kg-1 in herbal blend to 5,463 µg kg-1 in wormwood tea. Ochratoxin A (OTA) and aflatoxin B1 (AFB1) were found in 10% and 20% of the samples at the concentrations ranged between 2.99-30.3 µg kg-1 and 3.40-23.7 µg kg-1. Studies of the tea infusion process indicated that 32-100% of…

Recent applications of carbonaceous nanosorbents for the analysis of mycotoxins in food by liquid chromatography: a short review

Carbonaceous nanomaterials (multi-walled carbon nanotubes (MWCNTs), graphene, and graphene oxide (GO)) have attracted attention over the last decade as adsorbents suitable for the analysis of organic and inorganic pollutants. In the present paper we review methods of mycotoxin analysis that involve sample extraction with carbonaceous nanosorbents, reported from 2011 onwards. Recent studies have highlighted the advantages of magnetically modified MWCNTs and GO in mycotoxin analysis, which may enable sample isolation through magnetic separation, reduce the interaction of nanoparticles, and enhance the recovery of analytes. The papers covered in this review point to promising applications of …

Divdimensionālās šķidruma hromatogrāfijas augstas izšķirtspējas masspektrometrijas metodes izstrāde mikotoksīnu noteikšanai Puer tējās

Maģistra darba ietvaros tika izstrādāta inovatīva divdimensionālās šķidruma hromatogrāfijas metode tandēmā ar augstas izšķirtspējas nolidojuma laika masspektrometriju (2D-LC-TOF-HRMS) 70 “jauno” un reglamentēto mikotoksīnu noteikšanai Puer tēju matricā. Šis uzdevums tika izvirzīts ar mērķi palielināt nosakāmo mikotoksīnu skaitu, uzlabot metodes selektivitāti un novērst traucējošo matricas komponentu efektu, pielietojot savienojumu atdalīšanu ar 2D-LC sistēmas palīdzību. Metode tika validēta saskaņā ar Eiropas Savienības analīzes metodes vadlīnijām. Izstrādātā online-heart-cutting-2D-HPLC-HRMS metode tika pielietota 20 Latvijā komerciāli pieejamajiem Puer tēju paraugiem, veicot analizēto mik…

Occurrence and risk assessment of mycotoxins, acrylamide, and furan in Latvian beer.

This work reports data on the occurrence of nine mycotoxins and two food processing contaminants - acrylamide and furan - in a total of 100 beers produced in Latvia. Mycotoxins were detected by high-performance liquid chromatography (HPLC) coupled with time-of-flight mass spectrometry, acrylamide by HPLC coupled with quadrupole-Orbitrap mass spectrometry, and furan by headspace gas chromatography-mass spectrometry. The most frequently occurring mycotoxins were HT-2 and deoxynivalenol (DON), which were detected in 52% and 51% of the analysed samples. The highest content was observed for DON, reaching the maximum of 248 µg kg-1. Furan was ubiquitous, and 74% of the samples contained acrylamid…

Two-dimensional liquid chromatography - high resolution mass spectrometry method for simultaneous monitoring of 70 regulated and emerging mycotoxins in Pu-erh tea

2-hlor-4-nitrobenzoskābes un tās izomēru solvātu un polimorfo formu iegūšana un raksturošana

2-hlor-4-nitrobenzoskābes un tās izomēru solvātu un polimorfu iegūšana unraksturošana. Bogdanova E., darba vadītājs Dr. Chem. Bērziņš A. Bakalaura darbs. 74 lappuses,40 attēli, 9 tabulas, 5 pielikumi, 48 literatūras avoti. Latviešu valodā. Bakalaura darba ietvaros ir apkopota informācija par 2-hlor-4-nitrobenzoskābi, tāsizomēriem, polimorfisma parādību, solvātiem, kā arī par rentgendifraktometriju,termogravimetriju, diferenciālo skenējošo kalorimetriju, diferenciāli termisko analīzi un kodolmagnētisko rezonansi, kā par metodēm, kas tika izmantotas pētījumos. Eksperimentālajā daļā ir veikta CNBA jeb hlornitrobenzoskābes izomēru pārkristalizēšana no 27 dažādiem šķīdinātājiem un tā rezultātā –…

A rapid and sensitive method for the control of selected regulated and emerging mycotoxins in beer

A fast method using automated online solid-phase extraction (SPE) coupled to liquid-chromatography/high resolution mass spectrometric (LC-HRMS) detection for the determination of 12 mycotoxins in beer was developed and fully validated according to the performance criteria set in the European Union (EU) guidelines. Mycotoxin detection was achieved by full-scan HRMS with electrospray ionisation in positive ion mode within 13 min. No significant matrix interferences were observed. The lowest limits of detection (LODs) were achieved for emerging mycotoxins (beauvericin and enniatins) and ochratoxin A at levels between 0.01 and 0.02 μg/l, while the overall LODs were in the range of 0.01-0.30 μg…

Determination of Fungi and Multi-Class Mycotoxins in Camelia sinensis and Herbal Teas and Dietary Exposure Assessment

In this paper, a study of fungal and multi-mycotoxin contamination in 140 Camellia sinensis and 26 herbal teas marketed in Latvia is discussed. The analysis was performed using two-dimensional liquid chromatography with time-of-flight mass spectrometry (2D-LC-TOF-MS) and MALDI-TOF-MS. In total, 87% of the tea samples tested positive for 32 fungal species belonging to 17 genera, with the total enumeration of moulds ranging between 1.00 &times

The expedient application of microbial fermentation after whole-wheat milling and fractionation to mitigate mycotoxins in wheat-based products

Abstract The effect of whole milling and fractionation of wheat grains from the 2017 and 2018 harvests on the mycotoxin transfer into milling products and the influence of microbial fermentation of such products on mycotoxin levels were analysed. Additionally, the identification and occurrence of fungal contamination in grains with different mycotoxin contamination levels was evaluated. The mycotoxin contents were determined by chromatography (HPLC-TOF-HRMS). The distribution of mycotoxins in wheat wholemeal fractions depended on wheat kernel contamination level. The flour fractions contained zearalenone (ZEN) from 59 to 92%, and deoxynivalenol (DON) and deoxynivalenol-3-glucoside (D3G) at …