Leszek Tymczyna’s research while affiliated with University of Life Sciences in Lublin and other places

This study presents the process of obtaining of antimicrobial selenium nanoparticles in propolis extract and quercetin using natural deep eutectic solvents (NDES). The extraction using NDES as solvent makes it possible to obtain extracts with a higher content of active compounds compared to extraction with water, especially as it concerns compounds with limited solubility in water. Based on the results, the highest content of flavonoids, terpenes and antioxidant activity were found in the propolis extract with the applied NDES citric acid-propanediol-proline. The total phenolic content of propolis extracts ranged from about 30 to 200 mg/g dry weight, and the flavonoid content ranged from about 3 to 70 mg quercetin equivalents. Spherical selenium nanoparticles obtained from propolis extract had a particle size of 279 nm, while Se NPs obtained from quercetin dissolved in NDES had a particle size of about 96.0 nm. Se NPs obtained in the presence of both quercetin and propolis extract had high antioxidant activity. The activity of selenium nanoparticles synthesized using propolis was confirmed against E. coli, P. aeruginosa, S. aureus and C. albicans. The MBC of the microorganisms were 25, 100, 100 and 25 mg/l, respectively for E. coli, P. aeruginosa, S. aureus and C. albicans.

Agriculture contributes significantly to anthropogenic emissions of greenhouse gases (GHG). Livestock production, including pig production, is associated with several gaseous pollutants released into the atmosphere, including carbon dioxide (CO2), methane (CH4), ammonia (NH3) and nitrous oxide (N2O). Emissions of volatile organic compounds (VOCs), including alcohols, aldehydes, and aromatic and aliphatic hydrocarbons, as well as typically odorous pollutants, are an inseparable element of raising and breeding farm animals. These emissions can degrade local and regional air quality, contribute to surface water eutrophication and acid rain, and increase the greenhouse gas footprint of the production sector. The paper is organized as follows. First, the sources and factors influencing the level of emissions from pig houses are described. Next, the effects of dietary methods (optimization of animal diets), hygienic methods (including microclimate optimization) and technological methods (application of technological solutions) for mitigating emissions from pigs are discussed.

The aim of the study was to assess the impact of the duration of the use of a biofiltration bed on the efficiency of biofiltration of sulphur compounds and on the physicochemical and microbiological properties of the bed. The study was carried out at an animal waste treatment plant. Two biofiltration chambers (beds A and B) filled with different organic mixtures (compost soil, peat, coconut fibre and oak bark) were used in the biofilter. Chromatographic analysis showed a very high rate of effectiveness in the first study period, irrespective of the packaging material used. The best effects were obtained for inorganic sulphur compounds (above 99%). The duration of use of the bed material was shown to affect the efficiency of biofiltration. After 3 years of operation, thiol degradation efficiency fell below 50%. The biological decomposition of inorganic compounds (H2S + SO2) was 73% and 59.6% in beds A and B, respectively. Analysis of the biofiltration material indicated stabilization of its physicochemical parameters. Numbers of bacteria were not found to be depend on the duration of use or the type of filtering media.

Introduction Inflammatory bowel diseases (IBD) are a group of chronic gastrointestinal tract disorders with complex etiology, with intestinal dysbiosis as the most prominent factor. In this study, we assessed the anti-inflammatory and antibacterial actions of the human cathelicidin LL-37 and its shortest active fragment, KR-12 in the mouse models of colitis. Materials and methods Mouse models of colitis induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) and dextran sulfate sodium (DSS) were used in the study. The extent of inflammation was evaluated based on the macro- and microscopic scores, quantification of myeloperoxidase (MPO) activity and microbiological analysis of stool samples. Results A preliminary study with LL-37 and KR-12 (1 mg/kg, ip, twice daily) showed a decrease in macroscopic and ulcer scores in the acute TNBS-induced model of colitis. We observed that KR-12 (5 mg/kg, ip, twice daily) reduced microscopic and ulcer scores in the semi-chronic and chronic TNBS-induced models of colitis compared with inflamed mice. Furthermore, qualitative and quantitative changes in colonic microbiota were observed: KR-12 (5 mg/kg, ip, twice daily) decreased the overall number of bacteria, Escherichia coli and coli group bacteria. In the semi-chronic DSS-induced model, KR-12 attenuated intestinal inflammation as demonstrated by a reduction in macroscopic score and colon damage score and MPO activity. Conclusions We demonstrated that KR-12 alleviates inflammation in four different mouse models of colitis what suggests KR-12 and cathelicidins as a whole are worth being considered as a potential therapeutic option in the treatment of IBD.

A series of poly(vinyl alcohol) (PVA) based liquid compositions with addition of zinc oxide, silver and copper nanoparticles has been prepared. The compositions also contained other consistency-forming organic components. The physico-chemical properties of the products have been determined. Their pH and density have been assessed. Also, the size of nanoparticles has been defined with using a dynamic light scattering technique. The compositions were subjected to XRD, FT-IR and microscopic analysis as well. Thanks to the incorporation of both metal oxide and metallic nanoparticles, it was possible to enrich the products with antibacterial properties. Their inhibiting properties in the growth of microorganisms have been confirmed against both Gram-negative and Gram-positive strains such as E. coli, S. aureus and P. aeruginosa. Thanks to the ability for solidification, the compositions may be applied on a bacterially contaminated surface, and after destroying the microorganisms and its solidification, it may be peeled off along with the dead bacterial film.

Livestock buildings are often contaminated with bacterial and fungal microflora. Animals living in the buildings, especially their excreta and secretions and their feed, can be a source of microorganisms, including pathogens. Significant microbial contamination occurs in pig houses, poultry houses and cowsheds. The microbes most frequently isolated from the air of these buildings are bacteria of the genera Streptococcus , Staphylococcus , Bacillus , and Clostridium and of the family Enterobacteriaceae . Among fungi, the most common are Aspergillus , Trichoderma , Penicillium , Cladosporium and Alternaria . Microbes present in livestock buildings often pose a hazard to workers, in whom they can cause infectious and allergic diseases, especially respiratory disease. Bacterial endotoxins may also pose a threat to humans and animals. For this reason it is important to carry out microbiological monitoring and preventive measures on livestock farms and to maintain appropriate environmental conditions. This will reduce microbiological contamination of livestock buildings and improve both workers’ health and animal welfare.

Introduction: At present, infections induced by staphylococci, especially methicillin-resistant Staphylococcus aureus (MRSA) are one of key therapeutic and epidemiological problems. Aim: The assessment of Staphylococcus aureus carrier state occurrence among a healthy adult population as well as determination of phenotypic and genotypic properties of the isolated strains. Material and methods: The study included 100 healthy individuals. Material for bacteriological evaluation was collected from the posterior pharyngeal wall and tonsils, nasal vestibule and the skin of anterior nares using a sterile swab. The isolates identified as Staphylococcus aureus were analysed further, towards slime-forming capacity and the presence of genes mecA and nuc. Results: The analysis included 300 samples obtained from the posterior vault of the pharynx and tonsils, nasal vestibule and the skin of nares. Pharyngeal and vestibular S. aureus carriage was determined in 20% of the examined adults, whereas in 11 people with recognized positive throat colonization, the concurrent presence of golden staph was detected in the vestibule of the nose and on the skin, in the nose region. Identification process indicated the occurrence of strains defective in clumping factor synthesis (5% of isolates) and lack of the coa gene (11% of examined isolates). The PCR technique used to screen for the presence of the mec gene, did not confirm it in any of the strains under study. All the isolates had the gene encoding the thermostable nuclease nuc. Conclusions: S. aureus is a pervasive pathogen in community settings with constantly changing trends.

The aim of the study was to assess the gut microbiota and selected haematological and biochemical blood parameters of weaned piglets following dietary supplementation with a probiotic and vitamin C. The piglets were divided into a control group (group C) and an experimental group (group E), with 30 piglets in each group. All animals received the same feed ad libitum . The animals in the control group (group C) received feed with no added probiotic and vitamin C. The piglets in the experimental group (group E) were given a supplement containing a probiotic ( Bacillus cereus 1×10 ⁹ CFU/kg) in the amount of 1.5 g/piglet/day and vitamin C in the amount of 300 mg/piglet/day. The supplement was administered for 28 days. The total numbers of bacteria of the family Enterobacteriaceae and of the genus Lactobacillus were determined in faeces. The erythrocyte count, haemoglobin level, haematocrit, leukocyte count, and percentages of neutrophils and lymphocytes were determined in the blood. The biochemical analysis concerned the concentration of triacylglycerols, total cholesterol, and LDL and HDL cholesterol. In group E a significant decrease (p<0.01) in the total number of Enterobacteriaceae bacteria was observed in the faeces of the piglets, accompanied by an increase in the number of lactobacilli relative to group C. E. coli was found to predominate over other microorganisms. Salmonella Choleraesuis bacteria were present in the faeces of both groups before administration of the supplement, but were not found after its use. The supplement with probiotic and vitamin C caused a significant increase in the erythrocyte, haemoglobin and haematocrit levels in the blood of the piglets and a significant decrease in the concentration of triacylglycerols, total cholesterol and LDL cholesterol.

Objective: The aim of the study was to assess the impact of a fattening season on the level of airborne chemical and microbial pollutants in the pig fattening house. Material and methods: Evaluation of the air composition as well as the microbiological air quality were made during 2 series, i.e. in the summer and winter period of fattening. Airborne gaseous pollutants were analyzed by gas (organic compounds) and liquid (inorganic compounds) chromatography methods. Air microbial contamination was determined in compliance with the Polish Standard PN-EN 13098:2007. Results: The air/gas composition in the pig unit showed that irrespective of the fattening season, the level of determined pollutants - especially ammonia, volatile organic compounds (VOCs), including methanethiol and total dust - could have an adverse effect on the health of swine facility workers. The investigated pig building was found to be a source of chemical pollutants as well as biological agents. The total bacterial count in 1 m3 of air was 3.6×106 and 4.6×106 cfu, during the winter and summer periods of fattening, respectively. Gram-positive cocci predominated in both seasons. In the winter, fungi of the Trichoderma genus were represented equally often. In the summer period, up to 90% of the isolated fungus was Aspergillus spp. Conclusions: Workers engaged in swine rearing and production are occupationally exposed not only to a high concentration of microbial contamination, but also to irritating and odorogenous volatile compounds. Thus, activities directed at the promotion of health prevention strategies, as well as effective guidelines for safe and hygienic animal housing, should be implemented.