Selenium speciation analysis for the investigation of selenium uptake for the hydroponically cultivated garlic samples

Selenium is a significant nutrient source for humans and plants. Currently, inorganic selenium, including selenate and selenite, is used to cultivate selenium-rich crops to manage people's selenium deficiency problems. Garlic, being a major accumulative plant in the Allium genus, can absorb selenium concentrations beyond 1000 mg/kg when grown in soils rich in selenium. In this study, garlic samples were germinated in a soilless medium and transfered to hydroponic cultivation medium containing three different levels of sodium selenite (Na2SeO3). The total amount of selenium in the roots and leaves of lyophilized 150 mu M garlic extracts was 43.8 +/- 33.2 and 62.7 +/- 16.4 mg/kg (n = 4), while the total amount of selenium in the enzyme-extracted leaves and roots was 10.3 +/- 2.0 and 10.6 +/- 5.9 mg/kg (n = 4). Furthermore, selenium speciation analysis revealed that MeSeCys and SeMet as the main organoselenium compounds in garlic. Additionally, unknown selenium species were detected, indicating the need for further research to identify them.