This review presents the comprehensive knowledge about the bidirectional relationship between polyphenols and the gut microbiome. The first part is related to polyphenols’ impacts on various microorganisms, especially bacteria, and their influence on intestinal pathogens. The research data on the mechanisms of polyphenol action were collected together and organized. The impact of various polyphenols groups on intestinal bacteria both on the whole “microbiota” and on particular species, including probiotics, are presented. Moreover, the impact of polyphenols present in food (bound to the matrix) was compared with the purified polyphenols (such as in dietary supplements) as well as polyphenols in the form of derivatives (such as glycosides) with those in the form of aglycones. The second part of the paper discusses in detail the mechanisms (pathways) and the role of bacterial biotransformation of the most important groups of polyphenols, including the production of bioactive metabolites with a significant impact on the human organism (both positive and negative).

The aim of this study was to evaluate the possibility of using insect flour for sponge cake supplementation. Consumer acceptance, chemical composition, textural properties, and microbiological characteristics were determined. The addition of mealworm flour significantly increased the content of...

Magnesium, zinc and calcium are the elements that are involved in the regulation of metabolic activity of yeast and/or other processes such as flocculation and cell division. The requirements for specific ions may be subject to changes in successive fermentations performed by the same biomass. The aim of this work was to analyze the changes in calcium, magnesium and zinc concentration in malt broth (9°P) and in the yeast over four successive fermentations. For all ionic species analysed, the qualitative uptake and release patterns observed during subsequent fermentations were similar. In the lag phase of the fermentation, yeast cells accumulated the metal ions under investigation, in order to liberate them later to an extent that depended on the specific metal and fermentation number. Some differences were noted when qualitative comparison of these processes was performed. During the first fermentation with the yeast culture, the maximum content of each ion in the yeast biomass was two-to threefold higher than in the subsequent fermentations. Calcium, magnesium and zinc levels in the biomass did not exceed 1, 6 and 0.6 mg/g yeast dry weight respectively.

The aim of this work was characterisation of functional properties of honey enriched with propolis and beebread. In first step of experiment, soft propolis extract (SPEx) was obtained by extraction of propolis with ethanol. SPEx (0.25 to 1.0% w/w) as well as beebread (5 to 15% w/w) were implemented into natural honey. Fortified honeys were investigated in terms of total phenolic content, radical scavenging activity and ferric reducing antioxidant power, also their effects on the micro-organisms growth was examined. It was found that beebread had the most significant influence on antioxidant properties. On the other hand, all tested honeys showed antibacterial activity against Escherichia coli but not against Micrococcus luteus. Honeys with 1% of propolis addition were the most effective in this case. Research has indicated that for antioxidant and antimicrobial properties of honey, it is beneficial to enrich it in both beebread and propolis.