Isolation Of Microorganisms Research Articles

Upcycling of the industrial waste as a sustainable source of axenic fungal strain (Aspergillus oryzae) for scale up enzymatic production with kinetic analysis and Box–Behnken design application

Abstract The utilization of industrial waste for valuable product synthesis is essential for mitigating the environmental impact of climate change and managing waste disposal challenges. Industrial waste is always a big challenge for global warming. In this study, a novel fungus strain was isolated, and identified as Aspergillus oryzae (AKMS), from the oily surface of industrial effluent from an oil industry. Submerged fermentation was exploited to achieve maximum lipases production. A sequence of batch experiments was performed, altering five primary components: sucrose (for carbon), molasses (constituting nutrient mix), yeast extract (as nitrogen supply), sunflower oil (used as an activating agent), and Tween-80 (functioning as an emulsifying agent). These elements are recognized for their substantial impact on the proliferation of microorganisms and, consequently, the synthesis of lipases. The maximum lipase activity for each ingredient was determined, with sucrose showing 2.4 ± 0.539 U/mL at 0.15 g/L, molasses at 1.499 ± 0.291 U/mL at 0.25 g/L, Tween 80 % at 3.33 ± 0.484 U/mL at 0.25 g/L, sunflower oil at 7.49 ± 0.282 U/mL at 1 % v/v, and yeast extract at 4.165 ± 0.841 U/mL at 0.075 % v/v. The optimization of the lipase production and activity was done by using RSM (Box–Behnken design) with the 41st run yielding the maximum activity of 9 U/mL, while the 25th run showed the minimum activity of 4 U/mL, enzyme estimation (U/mL and U/g), glucose (g/L), and dry cell mass estimation (g/L) were monitored up to 120 h of fermentation in a custom-made fermenter with a working volume of 7 L. The highest production of extracellular and intracellular lipases (27.4 ± 0.378 U/mL and 25.4 ± 0.208 U/g, respectively) was observed at the 40 h interval, with the highest value of dry cell mass at 20 g/L. Glucose concentration initially peaked and subsequently decreased over time. A. oryzae exhibited the capability to produce triacyl glycerol acyl hydrolases, demonstrating its potential significance in biotechnological applications. These novel findings shed light on the efficient utilization of oil industry waste soil for isolation of microorganism for sustainable lipase production and highlight the biotechnological promise of the novel isolated fungal strain, which was reported first time in this study.

Bioprospecting the potential of the microbial community associated to Antarctic marine sediments for hydrocarbon bioremediation.

Microorganisms that inhabit the cold Antarctic environment can produce ligninolytic enzymes potentially useful in bioremediation. Our study focused on characterizing Antarctic bacteria and fungi from marine sediment samples of King George and Deception Islands, maritime Antarctica, potentially affected by hydrocarbon influence, able to produce enzymes for use in bioremediation processes in environments impacted with petroleum derivatives. A total of 168 microorganism isolates were obtained: 56 from sediments of King George Island and 112 from Deception Island. Among them, five bacterial isolates were tolerant to cell growth in the presence of diesel oil and gasoline and seven fungal were able to discolor RBBR dye. In addition, 16 isolates (15 bacterial and one fungal) displayed enzymatic emulsifying activities. Two isolates were characterized taxonomically by showing better biotechnological results. Psychrobacter sp. BAD17 and Cladosporium sp. FAR18 showed pyrene tolerance (cell growth of 0.03gmL-1 and 0.2gmL-1) and laccase enzymatic activity (0.006 UL-1 and 0.10 UL-1), respectively. Our results indicate that bacteria and fungi living in sediments under potential effect of hydrocarbon pollution may represent a promising alternative to bioremediate cold environments contaminated with polluting compounds derived from petroleum such as polycyclic aromatic hydrocarbons and dyes.

BD Chloraprep™ (“2 % chlorhexidine with 70 % isopropyl alcohol”) versus povidone iodine plus alcohol, for prevention of blood culture contamination at children: An investigator-initiated, open-label, single centre, randomized controlled trial

IntroductionOne of the important problems that lower the diagnostic value of blood culture is contamination with skin organisms. The povidone-iodine, alcohol, and chlorhexidine gluconate alcohol are used for disinfection prior to blood sampling for culture. MethodsThe investigator-initiated, open label, single centre, randomised trial compared blood culture contamination rates between two groups of patients in which using a povidone iodine skin-preparation process with the contamination rate for using “2 % chlorhexidine with 70 % isopropyl alcohol” skin-disinfection. The patients who required sampling for blood cultures were included in the study and study period was from 15 March 2023 to 15 July 2023. ResultsA total of 400 blood cultures were obtained during the study, including 133 in the study group and 267 in the control group. In the total blood cultures, 11.75 % (n = 47) had microorganism isolation. Among them 39 (9.75 %) were contaminants and 8 (2 %) of them were true pathogens. The contaminant microorganisms were as following; 34 coagulase-negative Staphylococci, 3 Micrococcus spp, and 2 Streptococci viridans. The blood culture contamination rate in the study group was 5.3 % (n = 7) and 12.0 % (n = 32) in the control group, and significantly lower in the study group (p = 0.033). There is no significant difference regarding skin related side effects between two groups. ConclusionsThis study, showed that 2 % chlorhexidine gluconate in 70 % isopropyl alcohol is more efficacious in children than 10 % povidone-iodine preparations for disinfecting the skin prior to blood specimen collection for prevention of blood culture contamination.

Isolation and Identification of Microorganisms and Antibiotic Resistance Microorganisms from Beehives Located in Palm, Corn and Longan Plantations, Thailand.

This study aims to determine the prevalence of microorganisms and antibiotic-resistant microorganisms in beehives located on different plantations in Thailand. Seventeen swabs immersed in transport media were utilized for samples from different zones within beehives. Traditional microbial culture-based methods, biochemical tests, MALDI-TOF MS (VITEK® MS, bioMerieux, Marcy-l'Étoile, France), and antibiotic drug susceptibility (disk-diffusion) tests were used to detect microorganism and antimicrobial resistance bacteria. The results from 16 beehive swabs found Gram-positive bacteria at 59.5%, Gram-negative bacteria at 35.1%, and fungi (yeast) at 5.4%. These organisms are classified as 11, 11, and 2 types of Gram-positive bacteria, Gram-negative bacteria, and fungi (yeast), respectively. Furthermore, no organism showed resistance to vancomycin or cefoxitin for antibiotic drug susceptibility testing. In contrast, all Acinetobacter spp. were susceptible to ciprofloxacin, levofloxacin, ceftazidime, cefotaxime, imipenem, and meropenem, except for Acinetobacter schindleri, which was resistant to ceftazidime and cefotaxime. For other organisms, due to the limitations of tests to identify some environmental microbial species, the antimicrobial susceptibility test results cannot be interpreted as resistant or susceptible to the drug for these organisms. The study's findings will support prevention, healthcare services, and public health systems.

Microbial Profile of Tourniquets Used in Phlebotomy at a Rural Tertiary Care Teaching Hospital.

Background Reusable phlebotomy tourniquets may become contaminated through repeated use on the skin surfaces of multiple patients, the hands of healthcare workers, or various surfaces. Noncompliance with the protocol guidelines for managing tourniquets can contribute to the cross-transmission of microorganisms among patients. This study was conducted to determine the microbial flora and antimicrobial sensitivity pattern of reusable phlebotomy tourniquets. Methodology Tourniquets were randomly sampled across the different areas of the hospital and were transported to the microbiology laboratory for isolation, identification, and antibiotic susceptibility testing of microorganisms using standard microbiological techniques. Results The overall bacterial colonization rate of the 50 tourniquets was 80%. The most prevalent isolate on tourniquets was Coagulase-negative Staphylococcus (9, 22.54%), followed by Micrococcus (6, 15%), Staphylococcus aureus (5, 12.5%), diphtheroid (5, 12.5%), Acinetobacter (4, 10%) Enterococcus (3, 7.5%), Pseudomonas (3, 7.5%), Bacillus (3, 7.5%), and Escherichia coli (2, 5%). Conclusions Regular surveillance and disinfection of reusable tourniquets in resource-poor settings are recommended to decrease healthcare infections and the transmission of multidrug-resistant (MDR) strains.

Biodegradation of Poly(ethylene terephthalate) by Bacillus safensis YX8.

Due to the extensive utilization of poly (ethylene terephthalate) (PET), a significant amount of PET waste has been discharged into the environment, endangering both human health and the ecology. As an eco-friendly approach to PET waste treatment, biodegradation is dependent on efficient strains and enzymes. In this study, a screening method was first established using polycaprolactone (PCL) and PET nanoparticles as substrates. A PET-degrading strain YX8 was isolated from the surface of PET waste. Based on the phylogenetic analysis of 16S rRNA and gyrA genes, this strain was identified as Bacillus safensis. Strain YX8 demonstrated the capability to degrade PET nanoparticles, resulting in the production of terephthalic acid (TPA), mono (2-hydroxyethyl) terephthalic acid (MHET), and bis (2-hydroxyethyl) terephthalic acid (BHET). Erosion spots on the PET film were observed after incubation with strain YX8. Furthermore, the extracellular enzymes produced by strain YX8 exhibited the ability to form a clear zone on the PCL plate and to hydrolyze PET nanoparticles to generate TPA, MHET, and BHET. This work developed a method for the isolation of PET-degrading microorganisms and provides new strain resources for PET degradation and for the mining of functional enzymes.

Isolation and Identification of Microorganisms associated with high-quality and low-quality cosmetics from different brands in Mecca region -Saudi Arabia

Cosmetic products contain several components that are ideal for microbial growth, they exposed to contamination by pathogenic bacteria and fungi, and this may cause health risks such as skin and eye infections. In this investigation, 50 samples were obtained from various shops in Mecca region, Saudi Arabia. Collected samples include high-quality and low-quality brands of makeup. Results show that most cosmetics are contaminated with microorganisms. Bacterial and fungal isolates were identified by morphological and microscopic techniques, and confirmed by molecular methods: (16s rRNA) for bacterial isolates and (18s rRNA) for fungal isolates associated with cosmetics. In low-quality cosmetics, frequency of microbial growth is higher and more diverse than high-quality cosmetics. It has been observed the most contaminated product was in lip gloss and it follows by the lipstick. The most predominant species of bacteria are Staphylococcus aureus (27 %), E. coli (27 %), which follows by Streptococcus pneumonia (18 %), Staphylococcus epidermis (17 %), Bacilli subtilis (12 %), and Pseudomonas aeruginosa (5 %). Aspergillus sp is the most predominant fungi (57 %), which is followed by Penicillium sp. (29 %) and Rhizopus sp. (14 %). In high quality brands, the frequency of microbial growth was the highest in mascara, lip-gloss. The most predominant species of bacteria is Staphylococcus aureus (41 %), which follows by Bacilli subtilis and Pseudomonas aeruginosa and E. coli (17 %). Streptococcus pneumonia is the less dominant (5 %). There is no growth on media of fungi. Due to the large number of cosmetics brands in Mecca region and for consumer safety, this study is prepared.

Circulation of Antibiotic-Resistant Escherichia coli in Wild and Domestic Waterfowl in Ukraine.

Background: Antibiotic resistance is becoming an increasingly urgent problem for human and animal health due to the widespread use of antibiotics in medicine, veterinary medicine, and agriculture. At the same time, the natural reservoirs of antibiotic-resistant pathogens remain unclear. Wild birds may play a role in this due to their biology. Escherichia coli is a representative indicator pathogen for antibiotic resistance studies. Materials and Methods: In 2020-2021, sampling of feces and cloacal swabs from six species of wild waterfowl (Eurasian wigeon Anas penelope, Eurasian teal Anas crecca, white-fronted goose Anser albifrons, red-breasted goose Rufibrenta ruficollis, graylag goose Anser anser, shelduck Tadorna tadorna) and from two species of domestic waterfowl (ducks and geese) was conducted in the Kherson, Zaporizhzhia, Odesa, Kharkiv, and Cherkasy regions of Ukraine. Biological material was collected, stored, and transported in cryotubes with transport medium (brain heart infusion broth [BHIB] with the addition of 15% glycerol) in liquid nitrogen. Bacteriological studies were carried out according to standard methods for the isolation and identification of microorganisms. Drug resistance of E. coli was carried out by a standard disk diffusion method. Results: Bacteria representing six families (Enterobacteriaceae, Yersiniaceae, Morganellaceae, Bacillaceae, Pseudomonadaceae, Staphylococcaceae) were isolated from clinically healthy wild birds (wigeon, Eurasian teal, white-fronted goose, red-breasted goose, mallard, graylag goose, shelduck) in the southern regions of Ukraine with isolation rates ranging from 26.7% to 100%. A total of 19 E. coli isolates were cultured from 111 samples from wild birds, and 30 isolates of E. coli were cultured from 32 poultry samples. E. coli was isolated from birds of all species. The prevalence of E. coli ranged from 5.0% to 33.3% in wild waterfowl and from 90.9% to 100% in domestic waterfowl. The prevalence of multidrug-resistant (MDR) E. coli ranged from 10.0% to 31.8% in wild and domestic waterfowl: 3 of 15 (20%) specimens from wild mallard were MDR in the Kherson region, as well as 7 of 22 domestic ducks (31.8%) and 1 of 10 geese (10%) in the Kharkiv and Cherkasy regions. Isolates from wild birds were the most resistant to ampicillin (AMP), amoxiclav (AMC), amoxicillin (AMX), doxycycline (DO), and chloramphenicol (C). Isolates from poultry were resistant to ampicillin, amoxiclav, doxycycline, amoxicillin, chloramphenicol, and enrofloxacin (EX). Most of the other E. coli isolates from wild waterfowl were classified as non-multidrug-resistant (non-MDR) forms. Analysis of antibiotic sensitivity phenotypes showed that only four antibiotic-resistant phenotypes were detected among non-MDR bacteria, whereas among the MDR bacteria, two antibiotic-resistant phenotypes were detected in mallards and six in domestic waterfowl. Conclusion: The results of this study showed that wild waterfowl in Ukraine, which live in natural conditions and do not receive any antimicrobial drugs, are carriers of E. coli that are resistant to a number of antibiotics that are actively used in industrial poultry.

Carbapenemase-producing organisms under the covid 19 pandemic

Abstract Background Antibiotic resistance is a widely recognised public health problem. Probably the factor most clearly associated with the emergence of carbapenemase-producing organisms (CPOs) is the use of antimicrobials. During the covid-19 pandemic, most patients with covid-19 received antibiotics. In addition, it is possible that the extra burden of work affected antimicrobial stewardship and infection prevention and control (IPC). The aim of the present study was to investigate the association between the frequency of carbapenemase-producing organisms (CPO) isolates and the excess of workload experienced during the covid-19 pandemic in a regional hospital in south-eastern Spain. Methods Descriptive study. Isolates producing one or more carbapenemases were collected from January 2015 to March 2022. Isolates of the same microorganism were grouped by individual, assuming that they correspond to the same episode of infection or colonisation. To estimate the workload, the rate of admissions of covid-19 cases in intensive care (ICU) and the total number of beds in covid-19 ICU each month were collected. Results The frequency of episodes shows an upward trend since 2018. From the 4th quarter of 2020 there is a clear acceleration until the 2nd quarter of 2021 (20 episodes per month), when a decrease to less than pre-pandemic frequencies is observed (10 episodes per month). The increase in episodes is parallel to the beginning of c ovid-19 admissions observed from the 4th quarter onwards. The decrease of episodes coincides with the increase of bed capacity, even with a maintained rate of admissions. CPO with two carbapenamases occur regularly from the 2nd quarter of 2020. Conclusions The occurrence of CPO may be related to the burden of work in healthcare systems. Disruption of antimicrobial stewardship and IPC could mediate this relationship. The decrease of episodes with a maintained rate of admissions may indicate that antibiotic use is not directly associated with CPO emergence. Key messages • Maintaining healthcare capacities related to antimicrobial stewardship and IPC may be critical in limiting the emergence of CPO. • Antibiotic use may not be directly related to the increase of CPO.

Optimizing Eco-Friendly Degradation of Polyvinyl Chloride (PVC) Plastic Using Environmental Strains of Malassezia Species and Aspergillus fumigatus.

Worldwide, huge amounts of plastics are being introduced into the ecosystem, causing environmental pollution. Generally, plastic biodegradation in the ecosystem takes hundreds of years. Hence, the isolation of plastic-biodegrading microorganisms and finding optimum conditions for their action is crucial. The aim of the current study is to isolate plastic-biodegrading fungi and explore optimum conditions for their action. Soil samples were gathered from landfill sites; 18 isolates were able to grow on SDA. Only 10 isolates were able to the degrade polyvinyl chloride (PVC) polymer. Four isolates displayed promising depolymerase activity. Molecular identification revealed that three isolates belong to genus Aspergillus, and one isolate was Malassezia sp. Three isolates showed superior PVC-biodegrading activity (Aspergillus-2, Aspergillus-3 and Malassezia) using weight reduction analysis and SEM. Two Aspergillus strains and Malassezia showed optimum growth at 40 °C, while the last strain grew better at 30 °C. Two Aspergillus isolates grew better at pH 8-9, and the other two isolates grow better at pH 4. Maximal depolymerase activity was monitored at 50 °C, and at slightly acidic pH in most isolates, FeCl3 significantly enhanced depolymerase activity in two Aspergillus isolates. In conclusion, the isolated fungi have promising potential to degrade PVC and can contribute to the reduction of environmental pollution in eco-friendly way.

Expanding success in the isolation of abundant marine bacteria after reduction in grazing and viral pressure and increase in nutrient availability.

Isolation of microorganisms is a useful approach to gathering knowledge about their genomic properties, physiology, and ecology, in addition to allowing the characterization of novel taxa. We performed an extensive isolation effort on samples from seawater manipulation experiments that were carried out during the four astronomical seasons in a coastal site of the northwest Mediterranean to evaluate the impact of grazing, viral mortality, resource competition reduction, and light presence/absence on bacterioplankton growth. Isolates were retrieved using two growth media, and their full 16S rRNA gene was sequenced to assess their identity and calculate their culturability across seasons and experimental conditions. A total of 1,643 isolates were obtained, mainly affiliated to the classes Gammaproteobacteria (44%), Alphaproteobacteria (26%), and Bacteroidia (17%). Isolates pertaining to class Gammaproteobacteria were the most abundant in all experiments, while Bacteroidia were preferentially enriched in the treatments with reduced grazing. Sixty-one isolates had a similarity below 97% to cultured taxa and are thus putatively novel. Comparison of isolate sequences with 16S rRNA gene amplicon sequences from the same samples showed that the percentage of reads corresponding to isolates was 21.4% within the whole data set, with dramatic increases in the summer virus-reduced (71%) and diluted (47%) treatments. In fact, we were able to isolate the top 10 abundant taxa in several experiments and from the whole data set. We also show that top-down and bottom-up controls differentially affect taxa in terms of culturability. Our results indicate that culturing marine bacteria using agar plates can be successful in certain ecological situations. IMPORTANCE Bottom-up and top-down controls greatly influence marine microbial community composition and dynamics, which in turn have effects on their culturability. We isolated a high amount of heterotrophic bacterial strains from experiments where seawater environmental conditions had been manipulated and found that decreasing grazing and viral pressure as well as rising nutrient availability are key factors increasing the success in culturing marine bacteria. Our data hint at factors influencing culturability and underpin bacterial cultures as a powerful way to discover new taxa.

A comparative study on the removal and recovery of hexavalent chromium from tannery wastewater using an isolated strain Aspergillus proliferans LA and a known strain Aspergillus terreus

Isolation of a potent microorganism from the soil near tanneries and a comparative analysis of the removal and recovery of different concentrations of hexavalent chromium using known strain Aspergillus terreus and isolated strain Aspergillis proliferansLA are done. The isolated fungal species from the chromium contaminated soil sites located in the industrial area of Kanpur, U.P. were tested for its potential for the removal of hexavalent chromium from wastewater streams. The experiments were conducted comparing the biosorption efficiency of the isolated species Aspergillus proliferansLA and Aspergillus terreus by varying the initial Cr (VI) concentration and media constituents. The highest removal efficiency of 99.19% was shown by the isolated species Aspergillus proliferansLA for an initial Cr (VI) concentration of 10ppm followed by increasing the concentration to 50ppm whereas Aspergillus terreus showed 78.43% removal of hexavalent chromium. This was then followed by desorption using 0.8M NaOH and 75.12% hexavalent chromium was desorbed from the cells. The isolated strain Aspergillus proliferansLA was seen to show better removal and recovery results than the known strain Aspergillus terreus.

Biocontrol Potential of Serratia Marcescens (B8) and Bacillus sp. (B13) Isolated from Urban Mangroves in Raposa, Brazil.

This study analyzed the antifungal potential of 16 bacterial strains isolated from mangrove sediment. Bacterial selection was conducted in a solid medium. This was followed by the production and extraction of metabolites using ethyl acetate to evaluate chitinase production, antifungal activity, and toxicity toward Allium cepa and Tenebrio molitor. Bacterial strains B8, B11, and B13 produced the largest inhibition halos (>30 mm) toward Fusarium solani, Fusarium oxysporum, and Rhizoctonia solani fungi. Strains B1, B3, B6, B8, B11, B13, B14, and B16 produced chitinases. In assays using liquid media, B8 and B13 produced the largest inhibition halos. Exposing the fungal inocula to metabolic extracts of strains B6, B8, B11, B13, B14, B15, and B16 caused micromorphological alterations in the inocula, culminating in the inhibition of R. solani sporulation and spore germination. Toxicity tests using Allium cepa and Tenebrio molitor revealed that the metabolites showed low toxicity. Six of the bacterial strains were molecularly identified to species levels, and a further two to genus level. These included Serratia marcescens (B8), which exhibited activity in all tests. Mangroves provide a useful resource for the isolation of microorganisms for biocontrol. Among the isolates, Serratia marcescens and Bacillus spp. showed the greatest potential to produce metabolites for use as biocontrol agents in agriculture.

Prevalence of Colonization with Multidrug-Resistant Bacteria: Results of a 5-Year Active Surveillance in Patients Attending a Teaching Hospital.

Combating antimicrobial resistance (AMR) requires comprehensive efforts, such as screening to identify patients colonized by multidrug-resistant microorganisms (MDROs). The primary purpose of this study was to estimate the AMR pattern of methicillin-resistant Staphylococcus aureus (MRSA) isolated from nasal surveillance swabs and MDROs isolated from pharyngeal and rectal surveillance swabs in patients attending a teaching hospital. Data were sought retrospectively, from 1 January 2017 to 31 December 2021, from the records produced by the hospital microbiology laboratory. Duplicate isolates, defined as additional isolates of the same microorganism with identical antibiograms, were excluded. Among Staphylococcus aureus isolates from nasal swabs, 18.2% were oxacillin-resistant. Among Gram-negative bacteria, 39.8% of Klebsiella pneumoniae and 83.5% of Acinetobacter baumannii isolates were carbapenem-resistant. Resistance to three antibiotic categories was high among Acinetobacter baumannii (85.8%) and Klebsiella pneumoniae (42.4%). The present data highlight a high prevalence of MDRO colonization among patients admitted to the hospital and suggest that screening for MDROs could be an important tool for infection control purposes, especially in geographical areas where limiting the spread of MDROs is crucial. The results also underline the importance of active surveillance, especially for carbapenem-resistant, Gram-negative bacteria in reducing their transmission, especially in high-risk units.

Some aspects of nasopharyngeal microflora in children with psoriasis

Objective — to study the state of nasopharyngeal microflora in children with psoriasis depending on the clinical features of dermatosis and determine antibiotic susceptibility of isolated microorganisms. Materials and methods. The isolation of nasopharyngeal microorganisms and determination of their antibiotic susceptibility were performed in 57 children with psoriasis aged 4 to 17 using the bacteriological method (culture). Microbial growth was assessed according to four degrees of growth. Susceptibility to antibacterial drugs was evaluated based on the following criteria: sensitive, moderately resistant, and resistant. Study materials were statistically processed using the StatTech v. 3.1 software. Results and discussion. Most often, Staphylococcus aureus (S. aureus) associations were cultured from the nasopharynx (56.15 %) of children with psoriasis — in 12.28 % of cases, Enterococcus faecium (Ent. faecium) — in 21.05 %. Statistically significant differences in children with psoriasis were found between the colony growth rates of Ent. faecium and S. aureus (p < 0.001): massive microbial growth of Ent. faecium prevailed (64.91 %), and S. aureus was not isolated at all in the majority of children (29.82 %). Ent. faecium growth rates were statistically significantly different (p = 0.016) depending on psoriasis severity according to PASI: massive growth of microorganisms at PASI > 10 was found in 87.5 % of cases, and at PASI ≤ 10 — in 54.2 % of cases. The proportion of Ent. faecium resistant to antimicrobial drugs (43.18 ± 7.47) % was found to be more than two times higher than that of S. aureus (20.00 ± 6.32) %. The susceptibility testing for each microorganism individually showed that enterococci were 28 to 100 % susceptible to antibacterial drugs, while staphylococci had 42 to 100 % susceptibility. Statistically significant differences were found between the percentage of sensitivity of Ent. faecium to antibacterial drugs between the group of children with the first diagnosis of psoriasis and the group of children with its recurrences (p = 0.005), as well as by the duration of the disease (p < 0.001). Conclusions. The results of the study of children with psoriasis showed that there were bacterial associations isolated from the nasopharynx in the most significant number of cases with the predominance of Ent. faecium, which had massive growth in almost 65 % of cases and affected psoriasis severity according to PASI (OR 5.923; 95 % CI 1.387—25.300). The proportion of Ent. faecium resistant to antibiotics was higher than of S. aureus (p < 0.05), but with increasing duration of psoriasis, Ent. faecium susceptibility to antimicrobials increased (r = 0.439; p = 0.004). In general, S. aureus isolated from the nasopharynx of children with psoriasis had more pronounced antibiotic susceptibility than Ent. faecium.

Закваски спонтанного (естественного) брожения: особенности технологии и роль в современном хлебопекарном производстве

Sourdough bakery products have a wide range of tastes and aromas, an extended shelf-life, and other benefits that are important for food producers and consumers. Recent years have seen a growing research interest in the microbiome of bakery sourdoughs. The research objective was to generalize, systematize, and analyze modern data on spontaneous fermentation starters, their production methods, and their role in the technological process at modern bakeries.
 The study featured domestic and foreign monographs, research articles, and patents related to various aspects of the production and commercial use of spontaneously fermented baking starters. The search covered publications indexed in PubMed and eLIBRARY.RU in 2000–2022. The sources were selected based on such indicators as completeness, consistency, reliability, and relevance. The obtained data were analyzed and systematized in line with the method of apperception and holography.
 The analysis focused on the factors that affect the microbiome of baking starter cultures, in particular, spontaneous fermentation. Another aspect included the effect of the raw materials used at the stage of breeding spontaneous fermentation starter cultures on their quality indicators. The transformation of bioactive compounds in the process of sourdough fermentation proved to be an increasingly relevant research matter. Food producers are looking for more effective tools to develop bakery products with specific nutritional properties, e.g., lower glycemic index, increased content of bioactive nutrients, reduced acrylamide content, low gliadin allergenicity, etc. 
 The isolation and profiling of microorganisms included in the microbiome of spontaneous fermentation sourdough cultures is of practical interest because new strains might produce starter cultures intended for various target audiences.

Антагонистическая активность экстремофильных микроорганизмов в отношении фитопатогенов сельскохозяйственных культур

Wheat is a vital agricultural crop whose phytopathogens include fungi of the genera Fusarium and Alternaria. Synthetic pesticides, which are used to combat them, have a negative impact on the environment. Therefore, there is a need for developing safe and effective biopesticides. We aimed to create a consortium of extremophilic microorganisms isolated from natural sources to protect wheat from the diseases caused by Alternaria and Fusarium fungi.
 Ten isolates of extremophilic microorganisms were tested for their antimicrobial activity against Escherichia coli and their antagonistic activity against phytopathogens. Based on the results, we developed microbial consortia and evaluated their effectiveness in protecting wheat from phytopathogens.
 Five of the strains under study showed the highest activity, three of which were biocompatible, namely Leclercia sp., Sphingomonas paucimobilis, and Lactobacillus plantarum. Four consortia were created from these microorganisms, of which consortium B (with a 2:1:1 ratio of the strains, respectively) proved the most effective. In particular, it increased the area free from the phytopathogen by 4.2% compared to the average values of its individual microorganisms. Also, the consortium had a phytostimulating effect on wheat seedlings (germination of 73.2–99.6%) and protected the seeds infected with phytopathogens from morphometric changes.
 The resulting consortium can be used as a biopesticide since it is highly effective in protecting wheat from Alternaria and Fusarium pathogens.

Exploration of the Benefits of Biofertilizers for Attaining Food Security in Egypt’s Agriculture

Biofertilizers and biocontrol agents have been improved for several decades as microbiological tools that can provide beneficial outcomes in the growth and health of plants. Two field experiments were performed in the Scientific Farm of the Horticulture Department, Faculty of Agriculture, Minia University, Egypt during the winter of 2022/2023 using clay loam soil. Control plots were treated with the recommended rates of mineral fertilizer of NPK (100%) without inoculation, while other plots were inoculated with Egyptian isolates of effective microorganisms (EMs) (a mixture of Azotobacter chroococcum and Azospirillium brasilense) and strains of Bacillus spp.; the biofertilizers were applied to the soil through mixing with irrigation water. For mycorrhizae, Glomus mosseae and Glamus fasiculatum isolation stock cultures were combined to create the mycorrhizal inoculum. The results showed that biofertilizers with 75% NPK were the best. Biofertilizers changed the properties of soil, increased its content of beneficial microorganisms, increased the total good quality production of onion and potato and decreased the stress of chemical pesticides and mineral fertilizers on crop growth and productivity.

Analysis of etiologic structure and antibiotic resistance of the main pathogens of infectious complications in patients with acute leukemia

Objective. Analyze the etiological structure of infectious complications in patients with acute leukemia and determine the sensitivity to antibacterial drugs of the main pathogens.Materials and methods. The results of bacteriological cultures and antibiograms of 177 patients with acute leukemia and infectious complications for the period 2019–2021 were retrospectively studied.Results. In 2019, the frequency of isolation of Gr+ flora was 45.28% and Gr- was 54.72%; in 2020 the percentage of Gr+ bacteria was 34.62%, Gr− was characterized by 65.38%; in 2021 it was 41.3% and 58.7% respectively, (x2=0.20, p=0.66). In 2019, one of the main pathogens was Klebsiella pneumoniae (21%), which retained its positions by 2021 (13%; x2=0.05, p=0.82). The causative agent showed polyresistance to many antibiotics, except for imipenem (100%) and fosfоmycin (100%). In the period 2020–2021 Klebsiella pneumoniae began to compete with Stenotrophomonas maltophilia, which showed an increase in the detection rate from 11% to 17% (x2=29.46, p=0.0001). Having polyresistance, the pathogen showed 100% sensitivity only to ticarcillin/clavulanate and co-trimoxazole.Conclusion. In the absence of changes between the frequency of isolation of Gram-positive and Gram-negative microorganisms, the increase in the number of strains of Gram− microorganisms (K. pneumoniae and S. maltophilia) with multiple antibiotic resistance among the causative agents of infectious complications in patients with acute leukemia necessitates continuous microbiological monitoring to improve the tactics of antibacterial drugs.

Isolation and in vitro screening of the probiotic potential of microorganisms from fermented food products

IntroductionSeveral human health benefits have been ascribed to probiotics, while traditional fermented foods have been acknowledged as rather important sources of these microorganisms. The objective of this study was the isolation of microorganisms from fermented food products of both animal and plant origin and the evaluation of their probiotic potential.MethodsMicrobial isolation was performed from milk kefir and table olives, while an olive mill waste sample also was analyzed given its anticipated association with the autochthonous microbiota of olive drupes. Among the 16 macroscopically distinct recovered microorganisms, 14 microbial isolates were identified as presumptive lactic acid bacteria (LAB), whereas two isolates corresponded to yeasts. The microbial isolates exhibiting a reproducibly robust growth profile in appropriate culture broth media (11 out of the 16 isolates) were assessed for their probiotic potential based on a set of in vitro assays: resistance to low pH; autoaggregation; biofilm formation; antioxidant activity; and safety assessment through evaluation of hemolytic activity.Results and discussionBased on the collective evaluation of the results of the abovementioned assays, five presumptive LAB as well as the two yeast isolates were identified as exhibiting desirable in vitro probiotic traits. Hence, these microbial isolates could be regarded as good candidates for inclusion in further studies aiming, ultimately, at their potential utilization in novel functional food products.