Enterolignans enterolactone and enterodiol formation from their precursors by the action of intestinal microflora and their relationship with non-starch polysaccharides in various berries and vegetables

The aim of this work was to investigate the production of enterolactone (ENL) and enterodiol (END) both enterolignans, from their precursors by the action of intestinal microflora and their relationship with non-starch polysaccharides (NSP) in common plant foods such as berries and vegetables. For the investigation of the bioconversion of plant lignans the technique of in vitro fermentation was used and the quantitative analysis of their metabolites ENL and END was performed by HPLC with coulometric electrode array detection. The enterolignan production from various berries ranged from 7.8 to 382.8 nmol/g as well as from vegetables – from 10.5 till 91.2 nmol/g. By comparing different kind of berries, the cloudberry, raspberry, and strawberry were the best enterolignan producers. Considering vegetables, potatoes produced the highest quantity of total enterolignans. Garlic, zucchini and broccoli were the other good producers of enterolignans in this product group. The quantitative relationship between NSP components and their associated lignan metabolites were determined. The results showed that there is a correlation between the particularities of fermented food matrices and the production of enterolignans. For berries, an intermediate correlation was found between the total NSP and ENL values. For vegetables, higher correlations between NSP and END were found.