Chromatographic speciation of anionic and neutral selenium compounds in Se-accumulating Brassica juncea (Indian mustard) and in selenized yeast

Abstract

Selenium-accumulating plants such as Brassica juncea (Indian mustard) concentrate the element in plant shoots and roots. Such behavior may provide a cost-effective technology to clean up contaminated soils and waters that pose major environmental and human health problems (phytoremediation). Such ability to transform selenium into bioactive compounds has important implications for human nutrition and health. Element selective characterization of B. juncea grown in the presence of inorganic selenium under hydroponic conditions provides valuable information to better understand selenium metabolism in plants. The present work determines both previously observed organoselenium species such as selenomethionine and Se-methylselenocysteine and for the first time detects the newly characterized S-(methylseleno)cysteine in plant shoots and roots when grown in the presence of selenate or selenite as the only selenium source. A key feature of this study is the complementary role of selenium and sulfur specific chromatographic detection by HPLC with interfaced inductively coupled plasma mass spectrometry (ICP-MS) detection and by derivatization GC with interfaced atomic spectral emission. HPLC-ICP-MS limits of detection for such species were in the range 5-50 ng Se mL −1 in the injected extracts. Speciation profiles are compared with those of selenium-enriched yeast by both HPLC-ICP-MS and GC-AED.

Selenium induced lower respiratory potential in Glycine max (L.) Merr

“…They are called accumulators. Actively growing tissues usually contain the largest amounts of Se (Kahakachchi et al, 2004). Astragalus bisulcatus is reported to be the best Se accumulator.…”

“…Deficiency of Se can cause a heart disease, hypothyroidism and a weakened immune system (Ellis and Salt, 2003). Kahakachchi et al (2004) reported that Se has a cancer chemopreventive properties for humans. The daily intake of Se depends on its concentration level in food and on the amount of food consumed.…”

Se(IV), Se(VI), Cu and Zn phytotoxicity in correlation to their accumulation in <i>Sinapis alba</i> L. seedlings

“…Their reduced form (selenite) is built in amino acids and enzymes (Arvy 1993, Li et al 2008, Mazej et al 2008. Selenium lower toxicity in seedlings shoots can be explained by transformation of inorganic selenium to organic compounds that are transported from the roots to the shoots , Kahakachchi et al 2004). Many authors (de Souza et al 1998, Kahakachchi et al 2004, Zayed et al 1998 www.plantroot.org 18 2009) introduced very weak selenite translocation from the roots to the shoots and this statement also confirmed here introduced results (Table 3).…”

“…Selenium lower toxicity in seedlings shoots can be explained by transformation of inorganic selenium to organic compounds that are transported from the roots to the shoots , Kahakachchi et al 2004). Many authors (de Souza et al 1998, Kahakachchi et al 2004, Zayed et al 1998 www.plantroot.org 18 2009) introduced very weak selenite translocation from the roots to the shoots and this statement also confirmed here introduced results (Table 3). By this low translocation and Se storage in the roots can also explain many times higher IC 50 values for shoots than those for roots growth reduction.…”

Capillary electrophoretic determination of selenocyanate and selenium and tellurium oxyanions in bacterial cultures

“…Various instrumental techniques including capillary electrophoresis (CE), high performance liquid chromatography -inductively coupled plasma -mass spectrometry (HPLC-ICP-MS), and ion chromatography -inductively coupled plasma -mass spectrometry (IC-ICP-MS) have been used by others for the speciation of selenium/tellurium-containing compounds (Casiot et al, 2002;Vogt and Werner, 1994;Schlegel et al, 1996;Albert et al, 1995;Gilon and Potin-Gautier, 1996;Kannamkumarath et al, 2002;Kahakachchi et al, 2004;Caruso and B'Hymer, 2006).…”