Flaxseeds are typically consumed either as whole flaxseed, ground flaxseed, flaxseed oil, partially defatted flaxseed meal, or as a milk alternative. They are considered a rich source of vitamins, minerals, proteins and peptides, lipids, carbohydrates, lignans, and dietary fiber, which have shown hypolipidemic, antiatherogenic, anticholesterolemic, and anti-inflammatory property activity. Here, an in vitro batch culture model was used to investigate the influence of whole milled flaxseed and partially defatted milled flaxseed press cake on the gut microbiota and the liberation of flaxseed bioactives. Microbial communities were profiled using 16S rRNA gene-based high-throughput sequencing with targeted mass spectrometry measuring lignan, cyclolinopeptide, and bile acid content and HPLC for short-chain fatty acid profiles. Flaxseed supplementation decreased gut microbiota richness with Firmicutes, Proteobacteria, and Bacteroidetes becoming the predominant phyla. Secoisolariciresinol, enterodiol, and enterolactone were rapidly produced with acetic acid, butyric acid, and propionic acid being the predominant acids after 24 h of fermentation. The flaxseed press cake and whole flaxseed were equivalent in microbiota changes and functionality. However, press cake may be superior as a functional additive in a variety of foods in terms of consumer acceptance as it would be more resistant to oxidative changes.

on the content of phenolic compounds depends on two opposite outcomes: decomposition of heat-labile compounds and disruption of the cell wall followed by a release of covalently bound phenolic compounds [Wang et al., 2014]. Stating about a potential health effect of food components should be preceded by bioaccessibility assessments confirming that after the digestion process the compound of interest is still present and available for absorption. Bioaccessibility is defined as the amount of a compound that is released from the food matrix and is considered to be available for absorption through the gut wall [Fernández-García et al., 2009]. Bioaccessibility depends on processing and interactions with components of the food matrix, such as proteins for example. It may be determined by analysing the digesta after an in vitro gastro-intestinal digestion using enzymes under controlled conditions such as pH, temperature, ionic strength, and digestion time. Conducting human trials being costly and ethically disputable, simulated in vitro digestions have the advantage to be more rapid and less expensive [Minekus et al., 2014]. Gou Qi Zi, Lycii Fructus, wolfberry or goji berry are the names given to fruit of Lycium barbarum, a plant from the Solanaceae family, growing in the temperate and subtropical zones of the world [Levin et al., 2011]. In the traditional Chinese medicine, goji berries are recommended for their capacity to strengthen muscles, protect liver functions, regenerate the vital essence, and improve visual acuity [Huang, 1998]. Due to their potential benefits for human health