Obesity is a complex disease that increases the risk of other pathologies. Its prevention and long-term weight loss maintenance are problematic. Gut microbiome is considered a potential obesity modulator. The objective of the present study was to summarize recent findings regarding the relationships between obesity, gut microbiota, and diet (vegetable/animal proteins, high-fat diets, restriction of carbohydrates), with an emphasis on dietary fiber and resistant starch. The composition of the human gut microbiome and the methods of its quantification are described. Products of the gut microbiome metabolism, such as short-chain fatty acids and secondary bile acids, and their effects on the gut microbiota, intestinal barrier function and immune homeostasis are discussed in the context of obesity. The importance of dietary fiber and resistant starch is emphasized as far as effects of the host diet on the composition and function of the gut microbiome are concerned. The complex relationships between human gut microbiome and obesity are finally summarized.

Obesity is a complex disease increasing risk of other pathologies. Its prevention or long-term weight loss maintenance is problematic. Gut microbiome is considered a potential obesity modulator. The objective of the present study was to summarize recent findings regarding relationships between obesity, gut microbiota and diet, with emphasis on dietary fiber and resistant starch. Composition of the human gut microbiome and methods of its quantification are described. Products of the gut microbiome metabolism, such as short-chain fatty acids and secondary bile acids including their effects on the gut microbiota, intestinal barrier function and immune homeostasis are discussed in the context of obesity. Importance of dietary fiber and resistant starch is emphasized as far as effects of the host diet on the composition and function of the gut microbiome are concerned. Complex relationships between human gut microbiome and obesity are finally summarized.

Ethanol extracts obtained from 13 poplar propolis samples originating from various European countries by traditional maceration were tested for total polyphenols, flavonoid content, and antioxidant activity. Moreover, the content of 18 polyphenolic compounds (from the group of phenolic acids and flavonoids) was determined using the HPLC method. The inhibitory effect of six selected extracts with the highest activity was assessed by well-diffusion method against five strains (Bifidobacterium spp., L. rhamnosus, L. acidophilus, E. coli, and Bacteroides spp.) of intestinal bacteria self-isolated from the faeces of obese probands with the use of selective media. It was found that the antioxidant activity of propolis varied depending on geographical origin and even among samples from the same region, which indicates that some other factors also influence propolis quality. The samples of different geographical origin varied mainly in the share of individual phenolic compounds, and it was not possible to find a characteristic marker of origin, excluding the galangin present in the Polish samples only. Assessing the inhibitory activity of propolis (in the range of 70 mg to 10 µg per mL) indicated that the concentration of 100 µg/mL was found as being safe for tested fecal bacteria (Bifidobacterium spp., L. rhamnosus, L. acidophilus, E. coli, and Bacteroides spp.). As no negative effect of low doses of propolis on the intestinal microflora was found, it can be suggested that its use in recommended doses brings only beneficial effects to the body.

The utilization of poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) with entrapped fish oil (FO) loaded in collagen-based scaffolds for cutaneous wound healing using a porcine model is unique for the present study. Full-depth cutaneous excisions (5 × 5 cm) on the pig dorsa were treated with pure collagen scaffold (control, C), empty PLGA NPs (NP), FO, mupirocin (MUP), PLGA NPs with entrapped FO (NP/FO) and PLGA NPs with entrapped MUP (NP/MUP). The following markers were evaluated on days 0, 3, 7, 14 and 21 post-excision: collagen, hydroxyproline (HP), angiogenesis and expressions of the COX2, EGF, COL1A1, COL1A3, TGFB1, VEGFA, CCL5 and CCR5 genes. The hypothesis that NP/FO treatment is superior to FO alone and that it is comparable to NP/MUP was tested. NP/FO treatment increased HP in comparison with both FO alone and NP/MUP (day 14) but decreased (p < 0.05) angiogenesis in comparison with FO alone (day 3). NP/FO increased (p < 0.05) the expression of the CCR5 gene (day 3) and tended (p > 0.05) to increase the expressions of the EGF (day 7, day 14), TGFB1 (day 21) and CCL5 (day 7, day 21) genes as compared with NP/MUP. NP/FO can be suggested as a suitable alternative to NP/MUP in cutaneous wound treatment.

With increasing popularity of food delivery services, the microbial safety of transported meals should be ensured. An effect of the type of a meal (cooked rice; mashed potatoes; mushroom sauce), inner primary packaging (sugarcane bagasse [SB] tray; polypropylene [PP] tray), secondary container (polyester/polyethylene foam/aluminum foil [PPA] bag; PP box) on the time interval of the internal hot ready-to-eat (RTE) meal temperature decrease to the value critical for Bacillus cereus growth (40 °C) was tested during a simulated delivery; in aliquot samples of the same meals, B. cereus growth was quantified presuming a natural contamination of the meals. Type of a meal had no effect on the tested time interval (p > 0.05). Packaging a meal in the PP tray as compared to the SB tray and inserting primary trays into the PP box instead of PPA bag delayed (p < 0.05) the internal meal temperature decrease by 50 and 15 min, respectively. Average B. cereus counts in the naturally contaminated meals after the four-hour culturing at 40 °C was 2.99 log CFU·g⁻¹. It was concluded that a hot RTE meal delivered up to four hours under the tested conditions is not likely to facilitate B. cereus growth above unacceptable levels.

With increasing popularity of food delivery services, the microbial safety of transported meals should be ensured. An effect of the type of a meal (cooked rice; mashed potatoes; mushroom sauce), inner primary packaging (sugarcane bagasse [SB] tray; polypropylene [PP] tray), secondary container (polyester/polyethylene foam/aluminum foil [PPA] bag; PP box) on the time interval of the internal hot ready-to-eat (RTE) meal temperature decrease to the value critical for Bacillus cereus growth (40 °C) was tested during a simulated delivery; in aliquot samples of the same meals, B. cereus growth was quantified presuming a natural contamination of the meals. Type of a meal had no effect on the tested time interval (p > 0.05). Packaging a meal in the PP tray as compared to the SB tray and inserting primary trays into the PP box instead of PPA bag delayed (p < 0.05) the internal meal temperature decrease by 50 and 15 minutes, respectively. Average B. cereus counts in the naturally contaminated meals after the four-hour culturing at 40 °C was 2.99 log CFU/g. It was concluded that a hot RTE meal delivered up to four hours under the tested conditions is not likely to facilitate B. cereus growth above unacceptable levels.