Monoamine oxidase A (MAO-A) is a major enzyme responsible for the deamination of neurotransmitters such as serotonin (5-HT) in the central nervous system. The decrease in 5-HT levels is accompanied by disorders at the affective and somatic levels, leading to depression and disorders of the satiety center. The aim of this study was to evaluate the degree of MAO-A inhibition by chlorogenic acids, as well as green, light-, and dark-roasted coffee extracts and bioactive compounds from beans of the species Coffea canephora and Coffea arabica. Data for analysis was obtained using isothermal titration calorimetry and molecular docking. The results showed that caffeine and ferulic acid, as well as green Robusta coffee, demonstrated the greatest inhibition of MAO-A activity, which may increase the bioavailability of serotonin. We believe that green coffee shows potential antidepressant activity by inhibiting MAO-A, and may be used for treating depression and potentially, type 2 diabetes.

The paper presents the results of an evaluation of the quality of eggs from laying hens kept in caged and free range systems using traditional methods and ultra-weak luminescence (USL). It was found that the tested eggs were fresh and were characterized by the required quality, as demonstrated by analysis of the egg white and egg yolk. Eggs from free-range laying hens were characterized by an eight-fold higher emission of photons compared to eggs from caged hens, and they had over three times higher content of natural antioxidants in the form of carotenoids. Most probably, the higher number of photons emitted is associated with a higher content of biologically active substances in the material under study. Photon emission also varies in different ways depending on the specific hen breeding system. Differences in time in the identified maximum values of photon emission result from the composition of individual parts of the egg. Different times in which the emission peaks occurred for free-range eggs and for caged eggs were observed. The application of the USL method in order to confirm its usefulness in the assessment of food quality requires further research.

The aim of this study was to investigate the possibility of using Aronia melanocarpa, Chaenomeles superba, and Cornus mas leaf extracts as natural preservatives for pork meat products. Pork sausages were stored in modified atmosphere packaging (MAP) (80% N₂ and 20% CO₂) at 4 °C for 29 days. The total psychrotrophic counts (TPC) were determined during the storage period, along with the numbers of Enterobacteriaceae and lactic acid bacteria (LAB). The extracts improved the microbial quality of the meat products but to a lesser extent than sodium nitrate (III). They reduced the amounts of Enterobacteriaceae and LAB. The A.melanocarpa leaf extract showed the strongest preservative effect. The bacterial biodiversity of the meat products was investigated based on high-throughput sequencing of the 16S rRNA gene. Two predominant bacteria phyla were identified, Proteobacteria and Firmucutes, mostly consisting of genera Photobacterium, Brochothrix, and Carnobacterium. The extracts also influenced microbial community in sausages decreasing or increasing bacterial relative abundance. The extracts significantly inhibited lipid oxidation and improved the water-holding capacity of the meat, with C. superba extract showing the strongest influence. In addition, A. melanocarpa and C. superba improved the redness (a*) of the sausages. The results of this study show that A. melanocarpa, C. superba, and C. mas leaf extracts can extend the shelf life of meat products stored in MAP at 4 °C.