Selective Media Research Articles

Bacterial Pathogens in Processed Frozen Fish Samples from Pune City

Amongst non-vegetarian foods, fish foods include various alive and preserved fishes. The preserved fish and their products include loose and packaged salted, dried and frozen. The frozen fishes and their products are mainly export grade and in very little quantity they are used in local markets. Many times such processed frozen fishes are rejected due to presence of undesirable microorganisms and pathogens. In the present study processed frozen fish samples from local market of Pune city were collected and used for detection and isolation of bacterial pathogens. The fish samples collected were L-Sardine (Sardinella longiceps), Mackerel (Rastrelliger kanagurta), Croaker (Johnius spp.), Ribbon fish (Lepturacanthus savali), Lizard fish (Nodus indicus), Itoyori (Nemipterus peroni) and L-Jacket (Oligoplites saurus). The enrichment and selective media were used to detect and isolate the pathogens in the processed frozen fish samples collected. The bacterial pathogens found in these fish samples were E. coli, Salmonella paratyphi-B, Staphylococcus aureus, Bacillus cereus and Vibrio parahaemolyticus. The attention is needed to control and remove such pathogens from food as it is alarming at safety point of view of consumers.

In vitro effect of 1-methyltryptophan isomers on epithelial-mesenchymal transition transcription factors in tubular epithelial cells after ischemia-reperfusion injury.

The compound 1-methyltryptophan (1-MT) has been shown to act protectively in renal ischemia-reperfusion injury. Toll-like receptor 4 signaling is also a regular process of epithelial-mesenchymal transition (EMT) that can after ischemia-reperfusion injury (IRI) result in an increase in renal fibrosis. EMT is associated with specific transcription factors: Snai1, Snai2, Zeb1, and Twist. 1-MT could regulate EMT and act as an antifibrotic agent. This study aimed to investigate the effect of 1-MT on EMT transcription factors in tubular epithelial cells that underwent 30 min. Renal tubular epithelial cells (TECs) were isolated from Lewis rats using a standard protocol with Fe2O3 magnetic separation and selective media as previously mentioned. Cells were cultivated and divided into 4 groups, namely C-TECs: control cells, IRI-TECs: IRI-induced TECs, D-IRI-TECs: IRI-induced TECs treated with 1-methyl-D-tryptophan, and L-IRI-TECs: IRI-induced TECs treated with 1-methyl-L-tryptophan. IRI was induced in all groups for 30 min by mineral oil (except for C-TECs) followed by 48-hour reperfusion. RNA and proteins were isolated from harvested cells. Using a semi-quantitative polymerase chain reaction, we assessed the relative mRNA expression of EMT transcription factors Snai1, Snai2, Zeb1, and Twist. Hereby, we showed that the treatment of ischemia-induced TECs with both 1-MT isomers lowered the expression of EMT transcription factors Snai1 and Zeb1 which were increased by ischemia and reperfusion of TECs. This could act favorably in renal IRI decreasing EMT and renal fibrosis, therefore showing the potential of 1-MT as a part of therapy in renal transplantation aimed at renal ischemia-reperfusion injury.

Assessing performance of simplified bioassays for soil-borne pathogens in smallholder systems of western Kenya.

Soil-borne pathogens cause considerable crop losses and food insecurity in smallholder systems of sub-Saharan Africa. Soil and crop testing is critical for estimating pathogen inoculum levels and potential for disease development, understanding pathogen interactions with soil nutrient and water limitations, as well as for developing informed soil health and disease management decisions. However, formal laboratory analyses and diagnostic services for pathogens are often out of reach for smallholder farmers due to the high cost of testing and a lack of local laboratories. To address this challenge, we assessed the performance of a suite of simplified soil bioassays to screen for plant parasitic nematodes (e.g., Meloidogyne, Pratylenchus) and other key soil-borne pathogens (Pythium and Fusarium). We sampled soils from on-farm trials in western Kenya examining the impact of distinct nutrient inputs (organic vs. synthetic) on bean production. Key soil health parameters and common soil-borne pathogens were evaluated using both simple bioassays and formal laboratory methods across eleven farms, each with three nutrient input treatments (66 samples in total). The soil bioassays, which involved counting galls on lettuce roots and lesions on soybean were well correlated with the abundance of gall forming (Meloidogyne) and root lesion nematodes (e.g., Pratylenchus) recovered in standard laboratory-based extractions. Effectiveness of a Fusarium bioassay, involving the counting of lesions on buried bean stems, was verified via sequencing and a pathogenicity test of cultured Fusarium strains. Finally, a Pythium soil bioassay using selective media clearly distinguished pathogen infestation of soils and infected seeds. When examining management impact on nematode communities, soils amended with manure had fewer plant parasites and considerably more bacterivore and fungivore nematodes compared to soils amended with synthetic N and P. Similarly, Pythium presence was 35% lower in soils amended with manure, while the Fusarium assays indicated 23% higher Fusarium infection in plots with amended manure. Our findings suggest that relatively simple bioassays can be used to help farmers assess soil-borne pathogens in a timely manner, with minimal costs, thus enabling them to make informed decisions on soil health and pathogen management.

Clinico-bacteriological Study and Molecular Detection of Campylobacter in Childhood Diarrhoea: A Cross-sectional Study

Introduction: Campylobacter infections cause diarrhoeal diseases as frequently as Salmonella and Shigella infections. The prevalence of Campylobacter infection among children with acute diarrhoea in developing countries ranges from 5-35%. Diagnosing Campylobacter infections is challenging as the organism is difficult to isolate, grow, and identify. Currently, no best-practice clinical or public health laboratory guidelines exist for laboratory diagnosis of Campylobacter infections. Aim: To explore the clinical and bacterial aspects of childhood diarrhoea, emphasising the prevalence and molecular detection of Campylobacter. Materials and Methods: A hospital-based cross-sectional descriptive study was conducted with 55 stool samples of children under five with diarrhoea or dysentery at the Department of Microbiology, JSS Medical College, Mysuru, Karnataka, India, from October 2016 to September 2017. All stool samples were inoculated onto Campylobacter selective and non selective media with filtration and incubated in microaerophilic conditions. The culture isolates were identified by standard phenotypic tests. Molecular characterisation of Campylobacter was performed targeting the Campylobacter adhesion to fibronectin F (cadF) gene. The presence of a phylogenetically conserved 16S ribosomal Ribonucleic Acid (16SrRNA) domain was studied, followed by specific detection of pathogenic Campylobacter species. The Statistical Package for Social Sciences (SPSS) version 22.0 was used for statistical analysis. Descriptive statistics like percentage, mean, and Standard Deviation (SD) were applied. Results: Campylobacter was isolated by culture in one out of 55 stool samples. The isolate was confirmed to be Campylobacter jejuni by phenotypic tests. Campylobacter genus-level Polymerase Chain Reaction (PCR) was positive for 6 samples (10.9%). Six positive samples were subjected to species-level PCR; all were positive for C. jejuni. Out of 55 stool samples, two diarrheagenic Escherichia coli, two Shigella sonnei, one Shigella dysenteriae, and one Salmonella enterica serovar Typhi were also identified. Conclusion: Culture is insufficiently sensitive for diagnosing Campylobacter infection compared with nucleic acid-based diagnostics. Nucleic acid-based diagnostics offer increased sensitivity, can determine both the presence and burden of infection, and can distinguish between Campylobacter infections at the species level. Therefore, PCR is recommended, if feasible, as the preferred diagnostic modality for detecting Campylobacter infection.

MICROBIOLOGICAL ASSESSMENT OF AIR BLOWN FROM ELECTRONIC HAND DRYERS IN PUBLIC RESTROOMS

The study was conducted locally to quantify and identify the microbial load in hand dryers installed in restrooms of eateries and malls. All the local malls and eateries were surveyed and petri plates containing nutrient and selective media were exposed to the air blown by the hand dryers installed in these places. Plates were incubated at 37 o C for 48 hours and colonies were counted. Air of the restrooms before switching on the dryers was used as control. It has been observed that most of the hand dryers are heavily contaminated with bacterial and fungal populations. Based on the colony characteristics, cultural characteristics and microscopic observations, most of the organisms have been identified to be potential intestinal pathogens.

Wonorejo mangrove indigenous bacteria: An insight into their potential as plastic-degrading agents

The use of bioplastic, such as polycaprolactone, to substitute conventional plastic remains a problem to solve. The bioplastic degradation time is still relatively low when compared to the rate of plastic consumption by the public. Therefore, exploration of indigenous bacteria with plastic-degrading potential is needed. This study aims to reveal the potential of indigenous bacteria isolated from Wonorejo Mangrove as plastic-degrading bacteria based on their growth in selective media and biofilm formation. Bacterial isolates obtained from water bodies and sediments of Wonorejo’s mangrove were inoculated on minimum salt media with the addition of 0.25% polycaprolactone as the sole carbon source and then incubated for four weeks to determine the bacterial growth based on its total number. The total number of bacteria was calculated by the direct counting method using a hemocytometer. The results indicated a slight decrease in the number of cells for each isolate. Isolate T1A.1 obtained from mangrove water samples encountered a decrease in the total number of bacteria by 2 times the initial number. Meanwhile, isolate T2.1, which was isolated from mangrove sediments, was decreased by 1.4 times from the initial number. However, the enumeration did not cover the cells that formed the biofilm, which was observed in this study. Based on the ability of the isolates to live in the minimum media and the biofilm formation indicated their potential as plastic-degrading agents, specifically for polycaprolactone. Identification and further studies of both isolates are needed to get a better insight into their potential as polycaprolactone-degrading agents.

First Report of Phytophthora citrophthora Causing Leaf Necrosis and Terminal Shoot Dieback on Asimina triloba (Pawpaw) in a Virginia Floodplain Forest

Asimina triloba (pawpaw) is a shade-tolerant, understory, deciduous tree in the family Annonaceae that is native to 26 states in the Eastern United States, with a range from the Florida panhandle to New York, west to Iowa and Nebraska, and south to Texas. On 12 June 2022, in a floodplain forest along the James River near Richmond, Virginia, a group of three A. triloba saplings about 1.0 to 1.5 m tall were observed with leaf necrosis, terminal shoot dieback, and leaf drop. Symptomatic tissue was cultured on selective media, and isolate DB22-4 was identified as Phytophthora citrophthora using morphological and molecular methods. Segments of the ITS and COX1 loci were deposited in the GenBank database under accession numbers OQ703042 and OQ834750, respectively. Koch's postulates were fulfilled in an unwounded, attached-leaf assay by inoculating 20 leaves on five healthy saplings. To the authors’ knowledge, this is the first report of P. citrophthora causing terminal necrosis and leaf drop on A. triloba in a nursery or a natural ecosystem. Additional studies are needed to understand which Phytophthora spp. cause disease on A. triloba, as well as the environmental and physiological factors that favor infection in the forest under natural conditions.

Obtaining stable strains of microorganisms with increased production of hydrolytic enzymes by methods of induced mutagenesis and their characteristics

In order to increase the level of production of hydrolytic enzymes of natural producers and select highly productive microorganisms, a study was carried out on the effectiveness of various approaches to induced mutagenesis, as well as a comparative study of the ability of exoenzymes biosynthesis by original and mutant strains. New mutant strains of B. subtilis and T. harzianum with some morphological deviations were obtained using multi-stage non-directional mutagenesis in a fractional mode followed by selection on selective media. These bacteria were superior to the parent strains of B. subtilis MB085-148-72 and T. harzianum MF091-07-305 in the number of hydrolytic enzymes produced. The stability of the characteristics of the new producers was confirmed by three successive subcultures on nutrient media containing the appropriate substrates of hydrolytic enzymes. Considering the high level of production of hydrolases of new strains of microorganisms, they can be recommended as components of feed additives, biopreservatives for silage and haylage, as well as effective producers of enzymes.

Comparative Evaluation of Antibacterial Activity of Three Different Universal Bonding Agents Against Streptococcus mutans and Enterococcus faecalis: An In Vitro Study

Abstract Aims: The purpose of this work is to assess the antibacterial activity of three distinct bonding systems, Single Bond Universal, Tetric N-Bond Universal, and One Coat 7.0 on Streptococcus mutans and Enterococcus faecalis. Materials and Methods: The antibacterial efficacy of dentin bonding systems against S. mutans and E. faecalis was investigated in this study. Standardized inoculums and selective media were used in this investigation, and the components that were analyzed were immediately used on the cultures. Dentin bonding system (4 mm × 4 mm) discs were created, cured, cleaned, and incubated with bacterial inoculums for 48 h. A colony counter was used to measure the colony-forming unit count. The dentin bonding agents evaluated in this study revealed different inhibitory effects. Statistical Analysis Used: Submitted to the analysis of variance. Results: Given the constraints of the current in vitro investigation, it was determined that the One Coat 7.0 Universal (Coltene) bonding agent showed the highest antibacterial activity against both S. mutans and E. faecalis. Conclusion: The dentin bonding agents taken in this study revealed different inhibitory effects on bacterial growth, in which One Coat 7.0 Universal (Coltene) bonding agent performed the highest antibacterial effect against both the bacteria taken in the study, that is S. mutans and E. faecalis. among all the three bonding agents taken.

Efficiency of chitosan-based edible films loaded with nano-emulsion essential oils against coagulase positive Staphylococcus aureus isolated from chicken meat

To decrease the incidence of coagulase positive Staphylococcus aureus (CPSA) in chicken meat, chitosan-based films incorporated with carvacrol nano-emulsion (Ch-CNE) and rosemary nano-emulsion (Ch-RNE) were used as an ideal solution to build effective antibacterial food packaging. CPSA was isolated from fresh and frozen chicken meat by using selective media. The prepared nano-emulsions were characterised using a zeta-sizer, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and investigated for anti-CPSA activity by the agar diffusion method. The filmogenic mixture was prepared at 0.78% and 1.56% concentrations and then cast, dried, and assessed for physical and mechanical properties. CPSA was isolated from fresh and frozen chicken meat in percentages of 40% and 12%, respectively. The droplet sizes of the CNE and RNE were 54.56 and 44.98 nm, respectively, whereas those by TEM were spherically shaped with average sizes of 40.33 and 48.78 nm and polydispersity indices (PDI) of 0.32 and 0.21, respectively. The minimum inhibitory concentrations of both nano-emulsions against CPSA were 0.78% and 1.56%. Incorporated nano-emulsions with chitosan-based films did not cause a great change in the film appearance and transparency except for Ch-CNE films at 1.56%, which was significantly different in comparison with the control, and enhanced the light barrier property. Additionally, it caused significantly improved changes to the film including physical (water resistance and water vapour permeabi­lity) and mechanical (tensile strength and elongation at break) properties and significantly eradicated the CPSA inoculated in chicken meat (6 log10 CFU/cm2) on the 4th day of refrigerated storage (4±1 °C) with good organoleptic properties for 12 days. The Ch-CNE at concentration 1.56% could be considered a promising antimicrobial food packaging material with considerable beneficial packaging properties, substantial inhibition of foodborne pathogen growth, and extension of food shelf life

Partial purification of linoleic acid isomerase enzyme from Lactobacillus paracasei bacteria isolated from milk.

Conjugated Linoleic Acid (CLA) has attracted the attention of many researchers, especially that of microbial origin due to its biological importance to the consumer. The current study aims to extract LA Isomerase enzyme from Lactobacillus paracasei bacteria from milk and to use the enzyme in the production of CLA. Selective media, including MRS and MRS-Dagatose, were used in isolating local strains. The selected bacterial isolates were tested for their ability to produce LA-Isomerase enzyme. The isolate with high enzymatic activity was selected. After extraction and partial purification of the enzyme, the optimal conditions for the production of conjugated fatty acid were studied, and the reaction products were diagnosed using GC-MS technology. It was found that 11 isolates have the ability to produce CLA at different concentrations, H1 isolate showed the highest production of conjugated fatty acid at a concentration of 120.45 g.ml-1, this isolate was selected as the source for enzyme extraction. The enzymatic activity of the crude extract and partially purified with ammonium sulfate was estimated using color methods at wavelength of 233 nm. The effect of the optimum conditions (pH, temperature, linoleic acid concentration and enzyme concentration) on the CLA product was studied using the partially purified LA Isomerase enzyme, the optimum conditions for production were 6.5, 45 °C, 100 μg.ml-1 and 0.7 ml, respectively. The GC-MS technique showed the presence of a number of reaction products that are isomers of conjugated linoleic acid (C9T11, T9T12, T10C12) with different concentrations.

Isolation and Characterization Morphology of Nitrogen-Fixing Bacteria from Mangrove Sediment

Mangrove ecosystems are coastal areas with ecological and socioeconomic functions. This area has a function as a nutrient provider for aquatic biota. The mangrove ecosystem also plays important role in nutrient cycling in coastal areas. The process of converting nitrogen into nutrients needed by plants (ammonium (NH4+) or nitrate (NO3+)) is called nitrogen fixation. The agents that play a role in this process are bacteria. The mangrove sediment has an abundant microbial communities which responsibility to this process. Sampling was carried out in the mangrove area of Tirang Beach, Semarang using the purposive sampling method. There are three sampling points, such as in the estuary, residential areas, and ponds. The isolation process was carried out using the spread plate method on solid NFB (Nitrogen Free Bromthymol) selective media, and purification using the quadrant streak plate method on the media. There are the most bacterial colonies in mangrove locations next to settlements, range from 2-11 bacterial colonies, and the least in mangrove locations near water bodies is 6 bacterial colonies. After purification, eight pure bacterial colonies have been identified and have similar morphological characteristics, white color, circular shape, entire margin, and flat elevation.

Isolation and Identification of Growth-Promoting Bacteria from Plants Growing Under Abiotic Stresses.

Identification and isolation of plant growth-promoting bacteria (PGPB) are critical steps toward understanding the role of these bacteria in stress tolerance in plants. This procedure also provides essential knowledge about the microbes needed to formulate effective biofertilizers. This chapter describes culture-dependent and culture-independent strategies to identify and isolate PGPB. The culture-dependent strategy commonly involves growing PGPB on general and selective media. However, the culture-independent strategy involves next-generation sequencing technologies. A combination of both strategies would identify the structure of the bacterial communities and isolate bacteria from their environments. Therefore, this chapter describes a comprehensive strategy where the methods are sequentially applied to identify and isolate epiphytic and endophytic PGPB from a particular environmental sample. However, a single procedure can also be employed to identify and isolate a specific type of PGPB.

Prospecção de Lactobacillus plantarum e Enterococcus faecium com potencial uso probiótico espécie-específico na aquicultura ornamental de Betta splendens Regan, 1910

ABSTRACT The research evaluated the isolation, identification, and prospection of species-specific beneficial bacteria in fish farming of ornamental fish Betta splendens. For this, the microbiological material was obtained from the intestinal tract of healthy specimens, with bacterial growth in selective culture medium Man Rogosa Sharped (MRS). Sixteen strains were isolated based on the response of in vitro tests of catalase, Gram, nilin blue, hemolytic activity and antibiogram to pathogens Aeromonas hydrophila, Pseudomonas aeroginosa, Enterococcus durans and Escherichia coli. Of the isolated strains C1BS and C5BS, they showed the best responses, which were later identified by the Maldi-TOF method as Lactobacillus plantarum and Enterococcus faecium. Due to the performance of lactic acid strains in in vitro tests and the bibliographic record of their performance as probiotics, the species have great potential for species-specific use in the ornamental production of Betta splendens.

Unraveling the complexity of Stenotrophomonas maltophilia – a comprehensive review of current knowledge

Abstract Stenotrophomonas maltophilia is a Gram-negative (G−) opportunistic pathogen, prevalent and concerning for susceptible patients. It primarily causes nosocomial and some community-acquired respiratory and bloodstream infections. Reservoirs include water, plant rhizospheres, food, and animals. Virulence factors include motility, biofilm formation, and quorum sensing, with ongoing research on these mechanisms. A major concern is its multidrug resistance to antimicrobial agents like trimethoprim-sulfamethoxazole (TMP-SMX), β-lactams, macrolides, fluoroquinolones, aminoglycosides, chloramphenicol, tetracyclines, and polymyxins. Effective treatments include TMP-SMX, quinolones, penicillins, and penicillins with β-lactamase inhibitors. Rapid diagnosis is crucial for successful treatment, leading to the development of new detection methods such as selective steno medium agar (SMA) and molecular techniques for nucleic acid detection. Patients with S. maltophilia are prone to co-infections with other G− bacteria. A study by Safdar et al. on cancer patients from 1986 to 2002 showed an increase in S. maltophilia infections from 2% to 7%, making it the 5th most commonly isolated G-bacterium in this group. It commonly infects ICU patients and individuals with SARS-CoV-2, with pneumonia being the most frequent clinical manifestation. The COVID-19 pandemic increased intensive care unit admissions and mechanical ventilation use, leading to higher infection rates of S. maltophilia.

Droplet microfluidic system for high throughput and passive selection of bacteria producing biosurfactants.

Traditional methods for the enrichment of microorganisms rely on growth in a selective liquid medium or on an agar plate, followed by tedious characterization. Droplet microfluidic techniques have been recently used to cultivate microorganisms and preserve enriched bacterial taxonomic diversity. However, new methods are needed to select droplets comprising not only growing microorganisms but also those exhibiting specific properties, such as the production of value-added compounds. We describe here a droplet microfluidic screening technique for the functional selection of biosurfactant-producing microorganisms, which are of great interest in the bioremediation and biotechnology industries. Single bacterial cells are first encapsulated into picoliter droplets for clonal cultivation and then passively sorted at high throughput based on changes in interfacial tension in individual droplets. Our method expands droplet-based microbial enrichment with a novel approach that reduces the time and resources needed for the selection of surfactant-producing bacteria.

A sustainable green solution to domestic sewage pollution: Optimizing floating wetland treatment with different plant combinations and growth media

Water quality degradation poses a global threat, with surface water resources bearing the brunt of pollution from various sources, including inadequately treated wastewater discharged from industrial and commercial processes. This discharge introduces a wide range of pollutants, compromising surface water quality and potentially contaminating groundwater. Floating Wetland Treatment (FWT) systems, particularly utilizing affordable and easy-to-construct bamboo rafts, emerge as a promising eco-technology offering a sustainable solution for rehabilitating water bodies polluted with inadequately treated domestic sewage. Research exploring the combined remediation potential of different plant combinations remains limited, although several studies demonstrate the efficacy of individual plant species in FWT systems. This study addresses this gap by evaluating the effectiveness of three terrestrial plant combinations (Canna indica, Chrysopogon zizanioides, and Hibiscus rosa-sinensis) supported by bamboo rafts in treating domestic wastewater. Among FWT methods, systems utilizing bamboo as floating rafts stand out due to their affordability, ease of construction, and adaptability to diverse plant species. FWT systems were meticulously designed with three plant combinations, utilizing soil and coco peat as growth media. Different FWT systems exhibited variations in their ability to remove several key water quality indicators. These variations were influenced by operational conditions, system design, plant selection, and growth media. Notably, the peat-based FWT system (FWT-BPCV) combining Canna indica and Chrysopogon zizanioides consistently demonstrated outstanding performance in reducing various pollutants, including total nitrogen (78.9 %), ammonia (90.2 %), total phosphorus (86.9 %), COD (92.8 %), BOD5 (94.8 %), TDS (70.7 %), TSS (93.6 %), turbidity (93.3 %), phosphate (73.2 %), electrical conductivity (62.5 %), and E. coli (78 %). This research suggests that FWT-BPCV is an eco-friendly wastewater treatment solution and an effective option for domestic wastewater treatment practices.

Foodborne Bacterial Pathogens in Animal, Food, and Environmental Samples Collected From the Physical Exposure of Children With Diarrhea in Ethiopia: A One Health Approach.

Foodborne pathogens (FBPs) are transmitted principally through the consumption of contaminated food or drinking water and pose a remarkable public health risk, particularly in low-income countries. A cross-sectional study was conducted between November 2021 and January 2023 to estimate the prevalence, co-occurrence, and monthly patterns of FBPs in the physical exposures of children with diarrhea in Harar town and Kersa district, Ethiopia. Animal, food, and environmental samples were collected from direct or indirect contact sites of children with diarrhea. The isolation and identification of FBPs, including nontyphoidal Salmonella (NTS), diarrheagenic E. coli (DEC), and Shigella, was performed using selective and deferential culture media and a series of biochemical tests. Among the 438 analyzed samples, the overall prevalence of these pathogens was 18.3%, with 3.9% co-occurrence and 14.4% single pathogen occurrence rates. The highest prevalence was observed in wastewater (40.9%; AOR = 3.3; 95% CI: 1.1-10.1). The pathogen detection rate in food was 17.9% (AOR = 1.2; 95% CI: 0.4-3.6), with no significant difference between animal-sourced and other food categories. The occurrence rates of NTS, DEC, and Shigella in the meat samples were 13.9%, 5.4%, and 6.5%, respectively. Interestingly, DEC and Shigella were detected in cooked food. Moreover, Shigella was detected in drinking water (5%) and other water sources (10%). A significantly higher prevalence of FBPs was detected in poultry than in cattle and camel feces. This study revealed fluctuations in the monthly occurrence patterns of FBPs, with a peak of 37.1% during the dry season. In conclusion, the study revealed a high prevalence of FBPs, with no significant differences between rural and urban areas or food and water sources, highlighting the need for food safety measures in both settings. Further studies with larger sample sizes and advanced diagnostics are recommended to determine the relative contribution of each source.

Солтүстік Қазақстан аймағының әртүрлі топырақ типтеріндегіазот бекітуші микроағзалардың таралуы

The use of biopreparations based on soil microorganisms to improve soil fertility, crop productivity and reduce the spread of fungal diseases of grain crops is one of the promising and environmentally friendly directions. This, in turn, requires comprehensive work on the creation, evaluation and introduction of highly effective Kazakhstani biological preparations. The article presents data on the distribution of nitrogen-fixing bacteria and actinomycetes on different types of soils in Northern Kazakhstan, identified by sowing soil suspensions by serial dilutions. More than 100 new strains of nitrogen-fixing bacteria and actinomycetes were isolated on solid selective nutrient media. In order to create a biofertiliser, the pathogenicity and growth intensity of new nitrogen-fixing bacteria and actinomycetes were studied, and their cultural and morphological characteristics were described. The 30 most active strains such as №21S, №19S, №31S, №91S, №3S, №56S, №51S, №62S, №55S, №70S, №53S, №20S, №2S, №81S, №7S, №54S, №57S, №35S, №84S, №22S, №9S, №12S, №8S, №10S, №69S, №52S, №49S, №11S, №6S, №59S, which will be used to make biologics. In the future, these strains will be studied for their growth-stimulating, fungicidal properties, etc., and will also be used in the development of microbiological technology for the production of biological preparations based on nitrogen-fixing and actinomycetes capable of increasing productivity.

Carbapenem-resistant Klebsiella oxytoca transmission linked to preoperative shaving in emergency neurosurgery, tracked by rapid detection via chromogenic medium and whole genome sequencing.

This study describes the detection and tracking of emergency neurosurgical cross-transmission infections with carbapenem-resistant Klebsiella oxytoca (CRKO). We conducted an epidemiological investigation and a rapid screening of 66 surveillance samples using the chromogenic selective medium. Two CRKO isolates from infected patients and three from the preoperative shaving razors had similar resistance profiles identified by the clinical laboratory. The whole genome sequencing (WGS) results identified all isolates as Klebsiella michiganensis (a species in the K. oxytoca complex) with sequence type 29 (ST29) and carrying resistance genes bla KPC-2 and bla OXY-5, as well as IncF plasmids. The pairwise average nucleotide identity values of 5 isolates ranged from 99.993% to 99.999%. Moreover, these isolates displayed a maximum genetic difference of 3 among 5,229 targets in the core genome multilocus sequence typing scheme, and the razors were confirmed as the contamination source. After the implementation of controls and standardized shaving procedures, no new CRKO infections occurred. Contaminated razors can be sources of neurosurgical site infections with CRKO, and standard shaving procedures need to be established. Chromogenic selective medium can help rapidly identify targeted pathogens, and WGS technologies are effective mean in tracking the transmission source in an epidemic or outbreak investigation. Our findings increase the understanding of microbial transmission in surgery to improve patient care quality.