Se improves indole glucosinolate hydrolysis products content, Se-methylselenocysteine content, antioxidant capacity and potential anti-inflammatory properties of sauerkraut

Selenium (Se) has a well-known role in prevention of chronic diseases associated with oxidative stress and inflammation. The objective was to produce Se-enriched sauerkraut and to study the effect of selenite addition on indole glucosinolate hydrolysis products, vitamin C, Se biotransformation and microbial quality. The antioxidant activity of sauerkraut and its ability to inhibit NO production in LPS-induced macrophages were also examined. White cabbage was naturally fermented with 0.3 mg of Na2SeO3/kg fresh cabbage (NFSe) or without Se addition (NF). Total Se content reached up to 1.29 μg/g d.m. (0.11 μg/g f.m.). Selenomethylselenocysteine was the major Se form found in NFSe cabbage. Se addition caused a slight reduction of ascorbigen (6%) and vitamin C (5%) contents in sauerkraut (P ⩽ 0.05); however, lactic acid bacteria increased (3%), and the formations of indole-3-carbinol and indole-3-acetonitrile were markedly enhanced (74% and 13%, respectively). NFSe cabbage extracts showed higher (P ⩽ 0.05) antioxidant activity (163 μmol trolox/g d.m.) and inhibition of NO production in LPS-induced macrophages (IC50 = 44.0 μg/ml) than did NF cabbage extracts. Consequently, Se-enriched sauerkraut can be considered as a health-promoting food.