Major ergot alkaloids in naturally contaminated cool-season barley grain grown under a cold climate condition in western Canada, explored with near-infrared (NIR) and fourier transform mid-infrared (ATR-FT/MIR) spectroscopy

Abstract

Globally, mycotoxins in food and feed are serious threats to the health of human and animals. Ergot alkaloids (EAs) are frequently detected in barley as well as other cereals. The purpose of this study was to examine the potential of applying NIR and ATR-FT/MIR spectroscopy for the determination of major EAs in cool-season barley samples grown under cold climate condition in western Canada. Sixty-seven cool-season barley samples were collected from Western Canada and analyzed for six major EAs by LC-MS/MS technique. Forty-nine barley samples were positive for EAs. The mean concentrations of ergocornine, ergocristine, ergocryptine, ergometrine, ergosine, ergotamine, and the sum-total EAs in positive barley samples were 120.9, 554.8, 235.6, 411.0, 127.4, 351.2, and 1150.5 μg/kg, respectively. The NIR (680–2500 nm) and MIR (4000-700 cm−1) spectra of cool-season barley samples were collected and calibrated with EAs reference values using PLS regression technique based on different spectral preprocessing methods and selected wavelengths. Results showed that most of the constructed models obtained weak calibration and cross-validation parameters and none of the models was able to accurately predict external samples. The relatively low levels of EAs in the contaminated barley samples might be lower than the detection limit of the conventional NIR and ATR-FT/MIR spectroscopy. More efforts are needed to study the determination limit of molecular spectroscopic techniques in detecting EAs in cereal grain grown under the cold climate condition.