Luminescent derivatives of benzanthrone are becoming more useful based on their light-absorbing and fluorescent-emitting properties. Our previous studies showed that luminescent staining properties of the same benzanthrone dye differ for variable parasite samples. Therefore, two types of benzanthrone dyes were prepared. One has a strongly basic amidine group and a halogen atom, and the other has an amide moiety and a tertiary amine group. Trematoda Parafasciolopsis fasciolaemorpha is a liver fluke of a moose (Alces alces) and has a significant influence on the health and abundance of the moose population. Staining protocols for parasite P. fasciolaemorpha specific organ or organ systems imaging are mostly time-consuming and labor-intensive. The study aimed to compare the fixation technique and the staining protocol by synthesized benzanthrone luminescent dyes to determine detailed morphology, anatomical arrangement of the organ systems and gross organization of the muscle layers of P. fasciolaemorpha using confocal laser scanning microscopy. Luminophores were tested for samples fixed in different fixatives. Developed dyes and staining protocol resulting in imaging of all parts of trematode without additional sample preparation procedures, which usually are required for parasite examination. Obtained results confirmed that the most qualitative results could be reached using 3-N-(2-piperidinylacetamido)benzanthrone dye which has amide moiety and a tertiary amine group. Based on obtained results, 3-N-(2-piperidinylacetamido)benzanthrone gave more qualitative parasite visualization than 2-bromo-3-N-(N′,N′-dimethylformamidino)benzanthrone.

An increasing number of bacteria have been described as benefiting from interaction with free-living amoeba. The most common association between free-living amoeba and microorganisms is interaction of various non-pathogenic and pathogenic bacterial species with amoeba. Various pathogenic bacterial species have capacity to resist digestion by free-living amoeba, which has been observed by many researchers. Also, several of these pathogens are able to resist digestion by macrophages. In addition, free-living amoeba have been associated with several diseases in humans. Acanthamniioeba castella is an important predator of bacteria. It is a ubiquitous organism in water, soil, and air. Attention from a public health perspective is needed by investigation of interaction of foodborne pathogens and free-living amoeba. Bacteria can use free-living amoeba as reservoirs, mediators or vehicles, an infection route, “biological gym” and evolutionary crib or interaction may result in a close endosymbiotic relationship. The purpose of this review is to describe the interaction mechanisms between free-living amoeba and common bacteria species that survive in host cells.

In this research, we studied the synthesis and characterization of a novel amidine derivative of benzoperimidine derived from 1-aminoanthraquinone, focusing on its emission properties and potential applications in confocal laser scanning microscopy. The synthesized compound exhibited pronounced solvatochromic behavior in various solvents. Spectroscopic analysis, including ¹H-, ¹³C-, and mass spectrometry, confirmed the chemical structure. The structure of three compounds was also determined using X-ray diffraction analysis; this study revealed the structural features of these substances in the solid state. The compound’s antimicrobial activity was evaluated using the agar diffusion method with the bacterium Bacillus subtilis subsp. Spizizenii. Furthermore, the study introduces a dye designed for imaging of the parasitic flatworm Opisthorchis felineus, demonstrating its potential in visualizing biological specimens.

Fluorescence imaging has emerged as a transformative tool in parasitological research, providing high-contrast visualization of complex morphologies often obscured in traditional bright-field microscopy. This review article synthesizes recent advancements in the application of polycyclic aromatic fluorophores, specifically benzanthrone and anthraquinone derivatives, for helminth imaging. It evaluates the critical interplay between chemical fixation strategies, such as ethanol-based protein precipitation, and optical clearing agents like ethanol–xylene and lactic acid to optimize tissue transparency for confocal laser scanning microscopy. Recent practical applications are examined across diverse taxa, demonstrating that the rational design of N-substituted sensors—including aminoamides and aminophosphonates—enables high-resolution characterization of muscular–tegumental systems and reproductive organs in under one hour. Key breakthroughs highlighted include the rapid sex determination of Trichinella larvae and the detailed resolution of the tripartite muscle framework in trematodes like Prosotocus confusus. These developments establish anthrone-based sensors as a robust, efficient alternative to conventional commercial kits, offering superior photostability and spectral tunability.