TY  - JOUR
A1  - Kroepfl, Nina
A1  - Francesconi, Kevin A.
A1  - Schwerdtle, Tanja
A1  - Kuehnelt, Doris
T1  - Selenoneine and ergothioneine in human blood cells determined simultaneously by HPLC/ICP-QQQ-MS
JF  - Journal of Analytical Atomic Spectrometry
N2  - The possible relevance to human health of selenoneine and its sulfur-analogue ergothioneine has generated interest in their quantitative determination in biological samples. To gain more insight into the similarities and differences of these two species, a method for their simultaneous quantitative determination in human blood cells using reversed-phase high performance liquid chromatography (RP-HPLC) coupled to inductively coupled plasma triple quadrupole mass spectrometry (ICP-QQQ-MS) is presented. Spectral interferences hampering the determination of sulfur and selenium by ICPMS are overcome by introducing oxygen to the reaction cell. To access selenoneine and ergothioneine in the complex blood matrix, lysis of the cells with cold water followed by cut-off filtration (3000 Da) is performed. Recoveries based on blood cells spiked with selenoneine and ergothioneine were between 80% and 85%. The standard deviation of the method was around 0.10 mg S per L for ergothioneine (corresponding to relative standard deviations (RSD) between 10-1% for ergothioneine concentrations of 1-10 mg S per L) and 0.25 g Se per L for selenoneine (RSDs of 25-2% for concentrations of 1-10 g Se per L). The method was applied to blood cell samples from three volunteers which showed selenoneine and ergothioneine concentrations in the range of 3.25 to 7.35 g Se per L and 0.86 to 6.44 mg S per L, respectively. The method is expected to be of wide use in future studies investigating the dietary uptake of selenoneine and ergothioneine and their relevance in human health.
Y1  - 2018
U6  - https://doi.org/10.1039/c8ja00276b
SN  - 0267-9477
SN  - 1364-5544
VL  - 34
IS  - 1
SP  - 127
EP  - 134
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Turrini, Nikolaus G.
A1  - Kroepfl, Nina
A1  - Jensen, Kenneth Bendix
A1  - Reiter, Tamara C.
A1  - Francesconi, Kevin A.
A1  - Schwerdtle, Tanja
A1  - Kroutil, Wolfgang
A1  - Kuehnelt, Doris
T1  - Biosynthesis and isolation of selenoneine from genetically modified fission yeast
JF  - Metallomics : integrated biometal science
N2  - Selenoneine, a naturally occurring form of selenium, is the selenium analogue of ergothioneine, a sulfur species with health relevance not only as a purported antioxidant but likely also beyond. Selenoneine has been speculated to exhibit similar effects. To study selenoneine's health properties as well as its metabolic transformation, the pure compound is required. Chemical synthesis of selenoneine, however, is challenging and biosynthetic approaches have been sought. We herein report the biosynthesis and isolation of selenoneine from genetically modified fission yeast Schizosaccharomyces pombe grown in a medium containing sodium selenate. After cell lysis and extraction with methanol, selenoneine was purified by three consecutive preparative reversed-phase HPLC steps. The product obtained at the mg level was characterised by high resolution mass spectrometry, NMR and HPLC/ICPMS. Biosynthesis was found to be a promising alternative to chemical synthesis, and should be suitable for upscaling to produce higher amounts of this important selenium species in the future.
Y1  - 2018
U6  - https://doi.org/10.1039/c8mt00200b
SN  - 1756-5901
SN  - 1756-591X
VL  - 10
IS  - 10
SP  - 1532
EP  - 1538
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  -