RESUMO
OBJECTIVE: To understand the absolute and relative concentrations of proteins,polysaccharides and nucleic acids that are Selenium-binding in Selenium-enriched Salvia miltiorrhiza, and to determine the efficiency of biotransformation of inorganic Selenium compounds in Salvia miltiorrhiza. METHODS: Extract the Selenium-binding proteins, polysaccharides and nucleic acids in Selenium-enriched Salvia miltiorrhiza using different solvents. Determine the concentrations of proteins, polysaccharides and nucleic acids by spectrophotometry, the concentration of Selenium by Hydride generation atomic fluorescence spectrometry. RESULTS: Selenium-binding proteins took up 74.2% of the total amount of Selenium in the tested Salvia miltiorrhiza, while Selenium-binding polysaccharides took up 39.5% and Selenium-binding nucleic acids took up 2.3%. Selenium that was bound with the water-soluble proteins came out as the most con- centrated, taking up 46.0% of the total amount of Selenium, during the extraction of Selenium using water, NaCl, ethanol and NaOH solution, respectively. Being extracted by the weak acid and alkali phosphoric acid buffer solutions, Selenium-binding proteins were more concentrated in the alkali buffer solution, taking up 51.2% of the total amount. CONCLUSIONS: In Salvia miltiorrhiza, Selenium exists mainly in the forms of selenium-binding proteins and Selenium-binding polysaccharides. Cultivation of Selenium-enriched Salvia miltiorrhiza achieves the biotransformation of inorganic Selenium compounds into organic compounds efficiently.
