Aneta A. Ptaszynska

This in vitro study compared the antimicrobial and antibiofilm efficacy of four commercially available chlorhexidine (CHX)-based mouthwashes, with different nominal CHX concentrations, against clinically relevant postoperative oral pathogens, including Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida auris. Antimicrobial potency was evaluated using MIC and CEMIC indices, while biofilm thickness reduction was quantified using 3D digital microscopy and custom image analysis software. Among the tested formulations, the excipient-enriched formulation exhibited the lowest MIC values and the most significant reduction in biofilm thickness, particularly against Gram-negative bacteria and Candida species. All mouthwashes achieved CEMIC < 0.1, confirming high theoretical applicability margins; however, CEMIC reflects potential clinical usefulness rather than clinical superiority. The findings demonstrate that the antimicrobial and antibiofilm activity of CHX rinses is formulation-dependent and cannot be predicted solely by CHX concentration. The influence of excipients is discussed as a possible contributing factor, but related mechanisms remain speculative and require direct validation in future studies. This work supports a formulation-driven, evidence-based approach to antiseptic comparison in postoperative dentistry, without assessing clinical wound-healing outcomes.

The aim of this study was to investigate the changes in the level of oxidative stress and lysozyme-like and phenoloxidase (PO) activity under the influence of nosemosis. Honeybees were kept in natural (apiary) and artificial (laboratory) conditions. In this study, it was shown for the first time that honeybees kept in apiaries have higher levels and activity of the studied parameters than honeybees kept in the laboratory. The greatest difference was noted in the case of PO activity in 28-day-old infected honeybees in May, when the activity was 32.3 times higher in honeybees kept in the apiary than in the laboratory, suggesting that environmental conditions have a significant influence on the immune response of honeybees. Simultaneously, the apiary conditions resulted in higher level of oxidative stress, indicating lower effectiveness of antioxidative mechanisms. Additional nosemosis infection increased the level of oxidative stress as well as lysozyme and PO activities. In July, in 28-day-old infected honeybees kept in laboratory, the highest increase in PO activity (by 10.79 fold) was detected compared to healthy honeybees. This may indicate that infection causes a decrease in the effectiveness of primarily antioxidant mechanisms, whereas immune mechanisms are still activated during infection. Another interesting factor is the age of the honeybees. It was found that in the summer months (June, July) the lysozyme-like and PO activities increased with age, while in the case of oxidative stress the opposite trend was observed, suggesting better effectiveness of both immune and antioxidant mechanisms. Another important element is seasonality, which significantly affected only the lysozyme-like activity. It was found that in July in all the groups studied this activity was higher than in the other months. The results allow us to better understand the mechanisms of honeybee immunity, which are constantly being studied due to the complex social structure created by these insects. Our research emphasizes that honeybee immunity is dynamic and depends on a number of factors, such as environment, age, season or the presence of pathogens.

An ethanol extract of Lasius fuliginosus ant nests was found to be highly effective against nosemosis in apiary honey bees. Two concentrations of the extract (300 mg and 1500 mg/100 ml sugar syrup) were tested on honey bees infected by nosemosis, and both significantly reduced the number of Vairimorpha ceranae DNA copies. Administration of the extract also had a positive effect on the honey bees’ immune system, increasing the expression of genes encoding immune peptides (abaecin, defensin-1, hymenoptaecin). The extract was subjected to detailed biochemical analysis for the presence of total carbohydrates (22.1 µg/ml), proteins (26.7 µg/ml), and phenolic compounds (63.8 μM) and also to assess its reducing activity (69.2% for DPPH radicals and 94% for the ABTS method). FTIR analysis revealed a number of groups and types of organic compounds (including fatty acids, triglycerides, formic acid, and phenols), the presence of which may have a decisive influence on the preparation’s high level of biological activity.

Despite the fact that there are many studies related to the adaptogenic and pro-healthy activities of plant-based compounds, there are some adaptogenic plants whose activities are not fully known, especially those coming from the wild regions of Asia, Africa, and South America. The aim of these studies was to examine the contents of non-nutritional compounds, such as polyphenols, flavonoids, and phenolic acids in ten adaptogenic species (Astragalus membranaceus (AM), Uncaria rhynchophylla (UR), Polygonum multiflorum (PM), Angelica sinensis (AS), Andrographis paniculatea (AP), Tinospora cordifolia (TC), Uncaria tomentosa (UT), Pfaffia paniculate (PP), Sutherlandia frutescens (SF), and Rhaponticum carthamoides (RC)). Considering biological activity, their antioxidant (DPPH, ABTS, FRAP, and ferrous-ion-chelating ability assays), anti-acetylcholinesterase, anti-hyaluronidase, and anti-tyrosinase activities were evaluated. The richest in polyphenols, flavonoids, and phenolic acids was UR (327.78 mg GAE/g, 230.13 mg QE/g, and 81.03 mg CA/g, respectively). The highest inhibitions of acetylcholinesterase, hyaluronidase, and tyrosinase were observed for TC, UR, and PM, respectively. In the case of antioxidant properties, extract from PM appeared to most strongly reduce DPPH, extract from UR inhibited ABTS, and extract from SF showed the best chelating properties. It should be noted that a particularly interesting plant was Ulcaria rhynchophylla. The results mean that there were compounds in UR with broad biological activities, and this species should be explored in more detail. Additionally, our results justify the traditional use of these species in the nutripharmacological or ethnopharmacological care systems of different regions.

Background: Microsporidia from the Nosema (Vairimorpha) genus are pathogenic fungi that complete their life cycle in the honeybee intestine. Therefore, the aim of this study was to determine the impact of the course of infection on the viability of honeybee intestine cells. Methods and Results: Intestines isolated from healthy and N. ceranae-infected honeybees were stained using two dyes, SYTO 9 and propidium iodide, and analyzed under an Axiovert 200M fluorescence microscope immediately after the isolation of the intestines. The ImageJ program was used for the quantitative analysis of the cell structure parameters. Our study demonstrated for the first time that healthy bees have a higher number of live cells in their intestines than infected bees, and that the intestines of N. ceranae-infected honeybees contain dead cells concentrated in spots. The results obtained for these two cases differed significantly, and were confirmed by statistical tests. Conclusions: The intestines of infected honeybees contain dead cells concentrated in red/dead spots, which can lead to necrotic changes, the interruption of the host’s intestinal continuity, intestinal leaking and the increased mortality of the host.

Due to a widespread occurrence of multidrug-resistant pathogenic strains of bacteria, there is an urgent need to look for antimicrobial substances, and honey with its antimicrobial properties is a very promising substance. In this study, we examined for the first time antimicrobial properties of novel varietal honeys, i.e., plum, rapeseed, Lime, Phacelia, honeydew, sunflower, willow, and multifloral-P (Prunus spinosa L.), multifloral-AP (Acer negundo L., Prunus spinosa L.), multifloral-Sa (Salix sp.), multifloral-Br (Brassica napus L.). Their antimicrobial activity was tested against bacteria (such as Escherichia coli, Bacillus circulans, Staphylococcus aureus, Pseudomonas aeruginosa), yeasts (such as Saccharomyces cerevisiae and Candida albicans) and mold fungi (such as Aspergillus niger). In tested honeys, phenolic acids constituted one of the most important groups of compounds with antimicrobial properties. Our study found phenolic acids to occur in greatest amount in honeydew honey (808.05 µg GAE/g), with the highest antifungal activity aiming at A. niger. It was caffeic acid that was discovered in the greatest amount (in comparison with all phenolic acids tested). It was found in the highest amount in such honeys as phacelia—356.72 µg/g, multifloral (MSa) and multifloral (MBr)—318.9 µg/g. The highest bactericidal activity against S. aureus was found in multifloral honeys MSa and MBr. Additionally, the highest amount of syringic acid and cinnamic acid was identified in rapeseed honey. Multifloral honey (MAP) showed the highest bactericidal activity against E. coli, and multifloral honey (MSa) against S. aureus. Additionally, multifloral honey (MBr) was effective against E. coli and S. aureus. Compounds in honeys, such as lysozyme-like and phenolic acids, i.e., coumaric, caffeic, cinnamic and syringic acids, played key roles in the health-benefit properties of honeys tested in our study.

The aim of this study was to detect and identify the volatile compounds in coffee that was obtained in defect roast processes versus standard roasting and to determine the type and strength of the correlations between the roast defects and the volatile compound profile in roasted coffee beans. In order to achieve this goal, the process of coffee bean roasting was set to produce an underdeveloped coffee defect, an overdeveloped coffee defect, and defectless coffee. The “Typica” variety of Arabica coffee beans was used in this study. The study material originated from a plantation that is located at an altitude of 1400–2000 m a.s.l. in Huehuetenango Department, Guatemala. The analyses were carried out with the use of gas chromatography/mass spectrometry (GC–MS) and an electronic nose. This study revealed a correlation between the identified groups of volatile compounds and the following coffee roasting parameters: the time to the first crack, the drying time, and the mean temperatures of the coffee beans and the heating air. The electronic nose helped to identify the roast defects.