Does selenium fortification of kale and kohlrabi sprouts change significantly their biochemical and cytotoxic properties?

• Published in: Journal of trace elements in medicine and biology 2020-05, Vol.59, p.126466, Article 126466
• Main Authors: Zagrodzki, Paweł, Paśko, Paweł, Galanty, Agnieszka, Tyszka-Czochara, Małgorzata, Wietecha-Posłuszny, Renata, Rubió, Pol Salvans, Bartoń, Henryk, Prochownik, Ewelina, Muszyńska, Bożena, Sułkowska-Ziaja, Katarzyna, Bierła, Katarzyna, Łobiński, Ryszard, Szpunar, Joanna, Gorinstein, Shela
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Antioxidants - analysis; Antioxidants - pharmacology; Biphenyl Compounds - antagonists & inhibitors; Brassica - chemistry; Cell Survival - drug effects; Chemical Sciences; Cytotoxic activity; Cytotoxins - analysis; Cytotoxins - pharmacology; Dose-Response Relationship, Drug; Food and Nutrition; Food engineering; Functional Food - analysis; Humans; Life Sciences; Phenolic acids; Picrates - antagonists & inhibitors; Plant Extracts - analysis; Plant Extracts - pharmacology; Seeds - chemistry; Selenium; Selenium - analysis; Selenium - pharmacology; Speciation analysis; Spectrometry, Fluorescence; Sprouts; Structure-Activity Relationship; Tumor Cells, Cultured
• ISSN: 0946-672X; 1878-3252
• DOI: 10.1016/j.jtemb.2020.126466

•Biochemical and cytotoxic properties of Brassica Se-fortified sprouts were examined.•About 10 % of selenium was incorporated into the sprouts as selenomethionine.•Selenium differently stimulated the production of phenolic acids in the sprouts.•Cytotoxic potency of sprouts regardless the Se fortification was observed.•Se-enriched sprouts are attractive candidates for functional food. The sprouts of Brassica vegetables are known from their nutritional and chemopreventive values. Moreover, sprouts fortification with some trace elements, like selenium, may increase their importance in human diet. Thus, the aim of our study was to examine if selenium enrichment of kale and kohlrabi sprouts may influence their biochemical properties (phenolic acids and L-tryptophan content, antioxidant potential) or cytotoxic activity. Additional aim of the study was to evaluate the profile of selenium compounds and to describe the multidimensional interactions between the mentioned parameters. Selenium content in the sprouts was evaluated by double-channel atomic fluorescence spectrometer AFS-230 with the flow hydride-generation system. Separation of selenium species in water soluble fraction was performed by size-exclusion LC-ICP-MS. The identification and quantification of phenolic acids and L-tryptophan was performed by HPLC. For antioxidant activity DPPH and FRAP methods were used. Cytotoxic activity of the sprouts extracts on a panel of human metastatic carcinoma cells was evaluated by MTT test. Selenium content in the fortified sprouts was several orders of magnitude higher than in the unfortified ones. Only small percentage of supplemented selenium (ca. 10 %) was incorporated into the sprouts as seleno-L-methionine, while the other detected selenium species remained unidentified. Selenium fortification differently stimulated the production of phenolic acids (sinapic, chlorogenic, isochlorogenic and caffeic acid) in the tested sprouts, depending on the particular species, selenium dose and the investigated compound. PCA analysis revealed strong correlation between antioxidant parameters and phenolic acids and L-tryptophan, while Se correlated only with caffeic acid. The sprouts extracts (≥1 mg/mL) showed cytotoxic potency to all the studied cancer cell lines (SW480, SW620, HepG2, SiHa), regardless the selenium supplementation. Se-fortified kale and kohlrabi sprouts are good candidates for functional food ingredients. Moreover, these results indicate that the sprouts enri