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The subject of the study is to indicate the situation of students and graduates on the Polish labour market, taking into account data on the number of students and graduates, as well as employment and unemployment statistics in selected years.

In order to meet the growing needs of the world economy for biotechnology, culture collections must transform the way they operate from passive storage of microbial resources to active microbial resource centers whose services should go beyond the provision of microbes. The protection and conscious use of microorganisms aims to co-create a strategy for responsible and sustainable development, based on expert knowledge. This article deals with the subject of the recently developed panel of biobank-specific standards and the requirements that must be met by culture collections to transform into modern microbial biobanks.

Modern research in food science and nutrition is transferring from classical methodologies to advanced molecular strategies in which next-generation sequencing (NGS) technology plays a crucial role. In this context, Foodomics has been recently defined as a new and global field using advanced “omics” technologies in food analysis. In recent years, “food-omics” technologies are widely applicated in food microbiology to identify, quantify and to track food microbial consortia in the food chain, as well as in the food safety and quality assessment. Metagenomics, referred to as community genomics is a sequence-based analysis of the collective genomes of microorganisms present in a given environment. This rapidly developing technique has provided new knowledge about taxonomic diversity and the dynamics of microbial communities at the genus, species and even strain level. An comprehensive metagenomic approach has proven to be a powerful tool in profiling the microbial ecology of complex ecosystems such as fermented foods. Currently, research focuses on understanding and controlling the fermentation process to ensure the consistent sensory properties of food products, increase safety and reduce food spoilage. The goal of this review is to provide an overview of the latest achievements of the “food-omics” technologies applied to biodiversity and functionality of food microflora, food safety and quality control. Furthermore, we discuss current challenges and future applications of “food-omics” technologies in the food industry.

Alicyclobacillus acidoterrestrisis a spore-forming bacterium, causing spoilage of juices. The spores of these bacteria have the ability to survive in the typical conditions used for thermal pasteurization. Therefore, the use of other techniques such as high hydrostatic pressure is considered for their inactivation. The effect of hydrostatic pressure of 200–500 MPa, at temperatures 4–50 °C for 15 min, on the dynamics of germination ofA. acidoterrestrisspores in apple juice and pH 4 buffer was studied. To estimate the share of germinated spores, the method of determining the optical density at a wavelength of 660 nm (OD660) was used. Parameters of hydrostatic pressure treatment used in this work affected the dynamics of germination ofA. acidoterrestrisspores in apple juice, and the temperature had the greatest effect. The results indicate that nutrients present in apple juice can promote the germination ofA. acidoterrestrisspores. [ABSTRACT FROM PUBLISHER]

Alicyclobacillus acidoterrestris, a thermoacidophilic and spore-forming bacterium, survives the typical pasteurization process and can cause the spoilage of juices, producing compounds associated with disinfectant-like odour (guaiacol, 2,6 – dibromophenol, 2,6 – dichlorophenol). Therefore, the use of other more effective techniques such as high hydrostatic pressure (HHP) is considered for preserving juices. The aim of this study was to search for factors affecting the resistance ofA. acidoterrestrisspores to HHP. The baroprotective effect of increased solute concentration in apple juice onA. acidoterrestrisspores during high pressure processing was observed. During the 45 min pressurization (200 MPa, 50°C) of the spores in concentrated apple juice (71.1°Bx), no significant changes were observed in their number. However, in the juices with a soluble solids content of 35.7, 23.6 and 11.2°Bx, the reduction in spores was 1.3–2.4 log, 2.6–3.3 log and 2.8–4.0 log, respectively. No clear effect of age of spores on the survival under high pressure conditions was found. Spores surviving pressurization and subjected to subsequent HHP treatment showed increased resistance to pressure, by even as much as 2.0 log. [ABSTRACT FROM AUTHOR]

The inactivation ofSaccharomyces cerevisiaeNCFB 3191 using high hydrostatic pressure of 300 MPa at 20°C with a holding time of 0, 1, 5 and 10 min was investigated with model suspensions in phosphate-buffered saline and in beetroot juice. The reduction inS. cerevisiaeNCFB 3191 in model suspensions was about 5 log after 10 min of pressurization, irrespective of the initial level of cell concentration in the samples (5.4–8.7 log cfu/mL). The baroprotective effect of beetroot juice on yeast cells during pressurization was observed; the reduction was lower and was only 3.5 log (the inoculum was 5.4 log cfu/mL). No sublethal injury among the surviving cells of the studied yeast strain was found. [ABSTRACT FROM AUTHOR]

Alicyclobacillus acidoterrestris, a thermoacidophilic and spore-forming bacterium is one of the important target micro-organisms in the quality control of acidic canned foods. High pressure pasteurization (HPP) at 50°C was used for the inactivation of A. acidoterrestris spores in apple juice. Pressure applied both in a continuous and oscillatory mode gave the best results when 200 MPa was used. Increasing the pressure to 500 MPa, as well as lowering its value to 100 MPa, had an adverse effect on the effectiveness of the process. The best results were achieved with the use of a combined treatment, involving oscillatory pressurization at 200 MPa, followed by holding the sample for 60 min at atmospheric pressure and subsequent pressurization at 500 MPa, resulting in a reduction in the spore count of 6.15 log. Nisin significantly enhanced the effect of HPP at 300 MPa. Using pressure of 200 MPa for 45 min with a nisin concentration of 250 IU/mL enabled total spore inactivation (over 6 log). No significant effect of lysozyme at a concentration of 0.05 and 0.1 mg/L at 300 MPa was observed. [ABSTRACT FROM PUBLISHER]

The superior thoracic aperture is a place particularly vulnerable to the occurrence of tissue conflict and the development of a number of neurovascular changes carrying a risk of upper limb dysfunction. The triggering factor in this case is the pressure on the nerve vascular elements brought about by too large muscles of the chest and neck, clavicle fracture and dislocation of the upper ribs, anomalies in the form of ribs, in the neck, or by apex of the lung tumors. Each anatomical anomaly may be a cause of a number of lesions and lead to the development of the disease. Due to the nature of the oppressed structures, there are two basic groups: neurogenic and vascular. The most common variant giving clinical symptoms is neurogenic thoracic outlet syndrome. In this, the compression ratio, the brachial plexus, and for this reason, the vascular surface of the upper limb dysfunction is often overlooked. However, the vascular variant, and especially arterial sub-variant, is very dangerous because it can give complications even in the form of aneurysms, and even upper limb ischemia. The aim of the study is to present the most common changes in the thoracic outlet causing functional disorders of the upper limb.

Abstract Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH). Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery.

The article focuses on the ongoing challenge of eliminating vegetative and spore-forming bacteria from food products that exhibit resistance to the traditional preservation methods. In response to this need, the authors highlight an innovative approach based on the synergistic utilization of high-hydrostatic-pressure (HHP) and lytic bacteriophages. The article reviews the current research on the use of HHP and lytic bacteriophages to combat bacteria in food products. The scope includes a comprehensive review of the existing literature on bacterial cell damage following HHP application, aiming to elucidate the synergistic effects of these technologies. Through this in-depth analysis, the article aims to contribute to a deeper understanding of how these innovative techniques can improve food safety and quality. There is no available research on the use of HHP and bacteriophages in the elimination of spore-forming bacteria; however, an important role of the synergistic effect of HHP and lytic bacteriophages with the appropriate adjustment of the parameters has been demonstrated in the more effective elimination of non-spore-forming bacteria from food products. This suggests that, when using this approach in the case of spore-forming bacteria, there is a high chance of the effective inactivation of this biological threat., Competing Interests: The authors declare no conflicts of interest.

Introduction: Ankylosing spondylitis is chronic progressive disease, which decrease functions of musculoskeletal system including chest area. Those changes influences respiratory mechanics, worsen conditions of proper ventilation of lungs., Objectives: Rating of functional and respiratory parameters and dependence between them at patients with ankylosing spondylitis., Materials & Methods: The study included 45 patients with diagnosed ankylosing spondylitis. Chest and upper limbs mobility, resting spinal curvature alignment were assessed, and respiratory parameters were measured in a plethysmographic chamber JAGGER MasterScreen Body., Results: Ankylosing spondylitis patients had lower respiratory parameters especially sReff, and FRC. Restriction of chest and upper limbs mobility was also demonstrated. Forward head extension was observed based on the occipital wall test. Correlations between functional parameters and correlations between functional and respiratory parameters were shown, in particular MIP, MEP, sReff, Rtot, TLC, ERV., Conclusions: The study confirmed a decrease in functional and respiratory parameters in the examined patients with ankylosing spondylitis compared to the applicable standards. A significant relationship was found between functional parameters in the upper body and respiratory parameters, which worsen with increasing thoracic dysfunction. The obtained results indicate the directions of therapy that should be taken into account to improve respiratory parameters and reduce respiratory dysfunction in these patients. Chest-focused physiotherapy appears to be an important element in improving function in patients with ankylosing spondylitis., (© 2024. The Author(s).)

The study investigates the antibiotic resistance (AR) profiles and genetic determinants in three strains of guaiacol-producing Alicyclobacillus spp. isolated from orchard soil and pears. Their phenotypic characteristics, such as spore formation; resistance to different factors, including drugs or disinfectants; or production of off-flavor compounds, can affect the taste and aroma of spoiled products. Food and beverages are potential vectors for the transfer of antibiotic resistance genes, which is a growing health concern; thus, microorganisms in food and beverages should not be a potential source of drug resistance to consumers. Whole-genome sequencing (WGS) was utilized to identify antibiotic resistance genes, metabolic pathways, and elements associated with guaiacol and halophenol production. Minimum inhibitory concentration (MIC) testing revealed that all strains were susceptible to eight out of nine tested antibiotics (ampicillin, gentamycin, kanamycin, streptomycin, clindamycin, tetracycline, chloramphenicol, and vancomycin) but exhibited high resistance to erythromycin. Analysis indicated that the erythromycin resistance gene, ribosomal RNA small subunit methyltransferase A ( RsmA ), was intrinsic and likely acquired through horizontal gene transfer (HGT). The comprehensive genomic analysis provides insights into the molecular mechanisms of antibiotic resistance in Alicyclobacillus spp., highlighting the potential risk of these bacteria as vectors for antibiotic resistance genes in the food chain. This study expands the understanding of the genetic makeup of these spoilage bacteria and their role in antimicrobial resistance dissemination.

Ostrich meat is an interesting alternative to poultry or beef due to its nutritional value. The addition of three plant species (hot peppers, acerola, Schisandra chinesis ) was suggested as a method to improve the quality, safety, and consumer acceptance of sausages prepared from ostrich meat. A series of microbiological and chemical analyses (including, inter alia, content of biogenic amines, heavy metals, and bioactive compounds) of the products as well as their sensory evaluation was performed to verify this claim. The microflora of all sausages was dominated by lactic acid bacteria. The biggest threat to consumers' health could be connected to the presence of biogenic amines formed through the enzymatic activity of lactic acid bacteria. The sausages with plant additives had better antioxidative and anti-inflammatory properties and lower fat oxidation-these features were correlated with the presence of vitamin C. Sausages with plant additives had a higher acceptability in terms of taste and smell.

Due to the high microbiological contamination of raw food materials and the increase in the incidence of multidrug-resistant bacteria, new methods of ensuring microbiological food safety are being sought. One solution may be to use bacteriophages (so-called phages) as natural bacterial enemies. Therefore, the aim of this study was the biological and genomic characterization of three newly isolated Serratia - and Enterobacter -specific virulent bacteriophages as potential candidates for food biocontrol. Serratia phage KKP_3708 (vB_Sli-IAFB_3708), Serratia phage KKP_3709 (vB_Sma-IAFB_3709), and Enterobacter phage KKP_3711 (vB_Ecl-IAFB_3711) were isolated from municipal sewage against Serratia liquefaciens strain KKP 3654, Serratia marcescens strain KKP 3687, and Enterobacter cloacae strain KKP 3684, respectively. The effect of phage addition at different multiplicity of infection (MOI) rates on the growth kinetics of the bacterial hosts was determined using a Bioscreen C Pro growth analyzer. The phages retained high activity in a wide temperature range (from -20 °C to 60 °C) and active acidity values (pH from 3 to 12). Based on transmission electron microscopy (TEM) imaging and whole-genome sequencing (WGS), the isolated bacteriophages belong to the tailed bacteriophages from the Caudoviricetes class. Genomic analysis revealed that the phages have linear double-stranded DNA of size 40,461 bp (Serratia phage KKP_3708), 67,890 bp (Serratia phage KKP_3709), and 113,711 bp (Enterobacter phage KKP_3711). No virulence, toxins, or antibiotic resistance genes were detected in the phage genomes. The lack of lysogenic markers indicates that all three bacteriophages may be potential candidates for food biocontrol.

Introduction: Novel technologies based on virtual reality (VR) are creating attractive virtual environments with high ecological value, used both in basic/clinical neuroscience and modern medical practice. The study aimed to evaluate the effects of VR-based training in an elderly population., Materials and Methods: The study included 36 women over the age of 60, who were randomly divided into two groups subjected to balance-strength and balance-cognitive training. The research applied both conventional clinical tests, such as (a) the Timed Up and Go test, (b) the five-times sit-to-stand test, and (c) the posturographic exam with the Romberg test with eyes open and closed. Training in both groups was conducted for 10 sessions and embraced exercises on a bicycle ergometer and exercises using non-immersive VR created by the ActivLife platform. Machine learning methods with a k -nearest neighbors classifier, which are very effective and popular, were proposed to statistically evaluate the differences in training effects in the two groups., Results and Conclusion: The study showed that training using VR brought beneficial improvement in clinical tests and changes in the pattern of posturographic trajectories were observed. An important finding of the research was a statistically significant reduction in the risk of falls in the study population. The use of virtual environments in exercise/training has great potential in promoting healthy aging and preventing balance loss and falls among seniors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Sokołowska, Świderski, Smolis-Bąk, Sokołowska and Sadura-Sieklucka.)

Background: Dynamic technological development and its enormous impact on modern societies are posing new challenges for 21st-century neuroscience. A special place is occupied by technologies based on virtual reality (VR). VR tools have already played a significant role in both basic and clinical neuroscience due to their high accuracy, sensitivity and specificity and, above all, high ecological value., Objective: Being in a digital world affects the functioning of the body as a whole and its individual systems. The data obtained so far, both from experimental and modeling studies, as well as (clinical) observations, indicate their great and promising potential, but apart from the benefits, there are also losses and negative consequences for users., Methods: This review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) framework across electronic databases (such as Web of Science Core Collection; PubMed; and Scopus, Taylor & Francis Online and Wiley Online Library) to identify beneficial effects and applications, as well as adverse impacts, especially on brain health in human neuroscience., Results: More than half of these articles were published within the last five years and represent state-of-the-art approaches and results (e.g., 54.7% in Web of Sciences and 63.4% in PubMed), with review papers accounting for approximately 16%. The results show that in addition to proposed novel devices and systems, various methods or procedures for testing, validation and standardization are presented (about 1% of articles). Also included are virtual developers and experts, (bio)(neuro)informatics specialists, neuroscientists and medical professionals., Conclusions: VR environments allow for expanding the field of research on perception and cognitive and motor imagery, both in healthy and patient populations. In this context, research on neuroplasticity phenomena, including mirror neuron networks and the effects of applied virtual (mirror) tasks and training, is of interest in virtual prevention and neurogeriatrics, especially in neurotherapy and neurorehabilitation in basic/clinical and digital neuroscience.

Mucoromycota is a phylum of early diverging fungal (EDF) lineages, of mostly plant-associated terrestrial fungi. Some strains have been selected as promising biotechnological organisms due to their ability to produce polyunsaturated fatty acids and efficient conversion of nutrients into lipids. Others get their lipids from the host plant and are unable to produce even the essential ones on their own. Following the advancement in EDF genome sequencing, we carried out a systematic survey of lipid metabolism protein families across different EDF lineages. This enabled us to explore the genomic basis of the previously documented ability to produce several types of lipids within the fungal tree of life. The core lipid metabolism genes showed no significant diversity in distribution, however specialized lipid metabolic pathways differed in this regard among different fungal lineages. In total 165 out of 202 genes involved in lipid metabolism were present in all tested fungal lineages, while remaining 37 genes were found to be absent in some of fungal lineages. Duplications were observed for 69 genes. For the first time we demonstrate that ergosterol is not being produced by several independent groups of plant-associated fungi due to the losses of different ERG genes. Instead, they possess an ancestral pathway leading to the synthesis of cholesterol, which is absent in other fungal lineages. The lack of diacylglycerol kinase in both Mortierellomycotina and Blastocladiomycota opens the question on sterol equilibrium regulation in these organisms. Early diverging fungi retained most of beta oxidation components common with animals including Nudt7, Nudt12 and Nudt19 pointing at peroxisome divergence in Dikarya. Finally, Glomeromycotina and Mortierellomycotina representatives have a similar set of desaturases and elongases related to the synthesis of complex, polyunsaturated fatty acids pointing at an ancient expansion of fatty acid metabolism currently being explored by biotechnological studies., (© 2023. The Author(s).)

Among the beer-spoiling microorganisms, the dominant ones belong to the genera Lactobacillus , Leuconostoc , Oenococcus , and Pediococcus . It is assumed that resistance to hop bitters correlates with resistance to other factors and can significantly impact the brewing industry. Beer preservation with high hydrostatic pressure eliminates the spoiling microorganisms while preserving all desired properties of the beer. Here, we present comprehensive in vitro and genomic analysis of the beer-spoiling Lactiplantibacillus plantarum KKP 3573 capacity to resist hop and high hydrostatic pressure. Lp. plantarum KKP 3573 is a strain isolated from spoiled beer. Our finding suggests that the growth rate of the strain depends on the medium variant, where a small concentration of beer (5 IBU) stimulates the growth, suggesting that the limited concentration has a positive effect on cell growth. At the same time, increased concentrations of 20 IBU, 30 IBU, and pure beer 43.6 IBU decreased the growth rate of the KKP 3573 strain. We observed that higher extract content in the pressurized beer increased microbial survivability. The wort and Vienna Lager beer can stimulate the baroprotective effect. The taxonomy of the novel strain was confirmed after whole genome sequencing (WGS) and comparative genomic analysis. More specifically, it contains a chromosome of 3.3 Mb with a GC content of 44.4%, indicative of the Lp. plantarum species. Accordingly, it possesses high genomic similarity (>98%) with other species members. Annotation algorithms revealed that the strain carries several genes involved in resistance to stress, including extreme temperature, hop bitters and high pressure, and adaptation to the brewing environment. Lastly, the strain does not code for toxins and virulence proteins and cannot produce biogenic amines.

The spoilage of juices by Alicyclobacillus spp. remains a serious problem in industry and leads to economic losses. Compounds such as guaiacol and halophenols, which are produced by Alicyclobacillus , create undesirable flavors and odors and, thus, decrease the quality of juices. The inactivation of Alicyclobacillus spp. constitutes a challenge because it is resistant to environmental factors, such as high temperatures, and active acidity. However, the use of bacteriophages seems to be a promising approach. In this study, we aimed to isolate and comprehensively characterize a novel bacteriophage targeting Alicyclobacillus spp. The Alicyclobacillus phage strain KKP 3916 was isolated from orchard soil against the Alicyclobacillus acidoterrestris strain KKP 3133. The bacterial host's range and the effect of phage addition at different rates of multiplicity of infections (MOIs) on the host's growth kinetics were determined using a Bioscreen C Pro growth analyzer. The Alicyclobacillus phage strain KKP 3916, retained its activity in a wide range of temperatures (from 4 °C to 30 °C) and active acidity values (pH from 3 to 11). At 70 °C, the activity of the phage decreased by 99.9%. In turn, at 80 °C, no activity against the bacterial host was observed. Thirty minutes of exposure to UV reduced the activity of the phages by almost 99.99%. Based on transmission-electron microscopy (TEM) and whole-genome sequencing (WGS) analyses, the Alicyclobacillus phage strain KKP 3916 was classified as a tailed bacteriophage. The genomic sequencing revealed that the newly isolated phage had linear double-stranded DNA (dsDNA) with sizes of 120 bp and 131 bp and 40.3% G+C content. Of the 204 predicted proteins, 134 were of unknown function, while the remainder were annotated as structural, replication, and lysis proteins. No genes associated with antibiotic resistance were found in the genome of the newly isolated phage. However, several regions, including four associated with integration into the bacterial host genome and excisionase, were identified, which indicates the temperate (lysogenic) life cycle of the bacteriophage. Due to the risk of its potential involvement in horizontal gene transfer, this phage is not an appropriate candidate for further research on its use in food biocontrol. To the best of our knowledge, this is the first article on the isolation and whole-genome analysis of the Alicyclobacillus -specific phage.

Due to irrational antibiotic stewardship, an increase in the incidence of multidrug resistance of bacteria has been observed recently. Therefore, the search for new therapeutic methods for pathogen infection treatment seems to be necessary. One of the possibilities is the utilization of bacteriophages (phages)-the natural enemies of bacteria. Thus, this study is aimed at the genomic and functional characterization of two newly isolated phages targeting MDR Salmonella enterica strains and their efficacy in salmonellosis biocontrol in raw carrot-apple juice. The Salmonella phage vB_Sen-IAFB3829 ( Salmonella phage strain KKP 3829) and Salmonella phage vB_Sen-IAFB3830 ( Salmonella phage strain KKP 3830) were isolated against S . I (6,8:l,-:1,7) strain KKP 1762 and S . Typhimurium strain KKP 3080 host strains, respectively. Based on the transmission electron microscopy (TEM) and whole-genome sequencing (WGS) analyses, the viruses were identified as members of tailed bacteriophages from the Caudoviricetes class. Genome sequencing revealed that these phages have linear double-stranded DNA and sizes of 58,992 bp (vB_Sen-IAFB3829) and 50,514 bp (vB_Sen-IAFB3830). Phages retained their activity in a wide range of temperatures (from -20 °C to 60 °C) and active acidity values (pH from 3 to 11). The exposure of phages to UV radiation significantly decreased their activity in proportion to the exposure time. The application of phages to the food matrices significantly reduced the level of Salmonella contamination compared to the control. Genome analysis showed that both phages do not encode virulence or toxin genes and can be classified as virulent bacteriophages. Virulent characteristics and no possible pathogen factors make examined phages feasible to be potential candidates for food biocontrol.

Innovative technologies of the 21st century have an extremely significant impact on all activities of modern humans. Among them, virtual reality (VR) offers great opportunities for scientific research and public health. The results of research to date both demonstrate the beneficial effects of using virtual worlds, and indicate undesirable effects on bodily functions. This review presents interesting recent findings related to training/exercise in virtual environments and its impact on cognitive and motor functions. It also highlights the importance of VR as an effective tool for assessing and diagnosing these functions both in research and modern medical practice. The findings point to the enormous future potential of these rapidly developing innovative technologies. Of particular importance are applications of virtual reality in basic and clinical neuroscience.

This article investigated the structure, and the spectroscopic and antimicrobial properties of mandelic acid and its alkali metal salts. The electron charge distribution and aromaticity in the analyzed molecules were investigated using molecular spectroscopy methods (FT-IR, FT-Raman, 1 H NMR, and 13 C NMR) and theoretical calculations (structure, NBO, HOMO, LUMO, energy descriptors, and theoretical IR and NMR spectra). The B3LYP/6-311++G(d,p) method was used in the calculations. The antimicrobial activities of mandelic acid and its salt were tested against six bacteria: Gram-positive Listeria monocytogenes ATCC 13932, Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, and Loigolactobacillus backii KKP 3566; Gram-negative Escherichia coli ATCC 25922 and Salmonella Typhimurium ATCC 14028, as well as two yeast species, Rhodotorulla mucilaginosa KKP 3560 and Candida albicans ATCC 10231.

Loigolactobacillus backii is an important beer-spoiling species, exhibiting high hop tolerance. Here, we present the annotated whole genome sequence of two recently isolated strains, Lg. backii KKP 3565 and KKP 3566. Firstly, to study the genetic basis of the persistence of the two isolates in beer, a comprehensive bioinformatic analysis ensued. Their chromosome map was constructed, using whole-genome sequencing and assembly, revealing that the two strains carry genomes with a length of 2.79 Mb with a GC content of 40.68%. An average nucleotide identity (ANI) analysis demonstrated that the novel strains possess unique genomic sequences, also confirming their classification into the Lg. backii species. Their genome harbors numerous insertion sequences and plasmids, originating from other beer-spoiling species. Regarding their adaptation in brewery environment, homologous genes that confer resistance to hop were spotted, while the impact of hop bitters and pure beer on bacterial growth was investigated, in vitro. In brief, low hop concentrations were found to induce the proliferation of strains, while a higher concentration negatively affected their growth. Nonetheless, their ability to survive in pure beer indicated their tolerance to high hop concentrations. These results offer insight into the capacity of Lg. backii KKP 3566 and Lg. backii KKP 3566 to tolerate the extreme conditions prevalent in the brewery environment.

This study aimed to evaluate the effectiveness of the phage cocktail to improve the microbiological quality of five different mixed-leaf salads: rucola, mixed-leaf salad with carrot, mixed-leaf salad with beetroot, washed and unwashed spinach, during storage in refrigerated conditions. Enterobacterales rods constituted a significant group of bacteria in the tested products. Selected bacteria were tested for antibiotic resistance profiles and then used to search for specific bacteriophages. Forty-three phages targeting bacteria dominant in mixed-leaf salads were isolated from sewage. Their titer was determined, and lytic activity was assessed using the Bioscreen C Pro automated growth analyzer. Two methods of phage cocktail application including spraying, and an absorption pad were effective for rucola, mixed leaf salad with carrot, and mixed leaf salad with beetroot. The maximum reduction level after 48 h of incubation reached 99.9% compared to the control sample. In washed and unwashed spinach, attempts to reduce the number of microorganisms did not bring the desired effect. The decrease in bacteria count in the lettuce mixes depended on the composition of the autochthonous saprophytic bacteria species. Both phage cocktail application methods effectively improved the microbiological quality of minimally processed products. Whole-spectral phage cocktail application may constitute an alternative food microbiological quality improvement method without affecting food properties.

The aim of this study was to isolate phage enzymes and apply them in vitro for eradication of the dominant saprophytic bacteria isolated from minimally processed food. Four bacteriophages-two Enterobacter -specific and two Serratia -specific, which produce lytic enzymes-were used in this research. Two methods of phage enzyme isolation were tested, namely precipitation with acetone and ultracentrifugation. It was found that the number of virions could be increased almost 100 times due to the extension of the cultivation time (72 h). The amplification of phage particles and lytic proteins was dependent on the time of cultivation. Considering the influence of isolated enzymes on the growth kinetics of bacterial hosts, proteins isolated with acetone after 72-hour phage propagation exhibited the highest inhibitory effect. The reduction of bacteria count was dependent on the concentration of enzymes in the lysates. The obtained results indicate that phages and their lytic enzymes could be used in further research aiming at the improvement of microbiological quality and safety of minimally processed food products., Competing Interests: The authors declare no conflicts of interest.