Single Bacterium Research Articles

Effect of the Thermophilic Bacterial Biculture Consortium from Mudiak Sapan Hot Springs on Biofuel Production

Biofuels are fuels derived from biomass and consist of biogas, biodiesel and bioethanol. Bioethanol is a biofuel whose main ingredients are from plants and generally use microorganisms in the fermentation process. One way is to use thermophilic bacteria with the advantage of low contamination levels and better product quality. Bacteria that exist in nature are not only in a single form but also exist in the form of a consortium in which there are beneficial or detrimental bacterial interactions. Favorable bacterial interactions indicate that the bacteria are compatible. Using a consortium with compatible bacteria gives better results than using a single bacteria. This study aims to determine the compatibility and effect of a consortium of thermophilic bacteria from Mudiak Sapan hot springs on biofuel yields. This research is a descriptive research. To test the cooperation between isolates, a compatibility test was carried out using the disk diffusion method. Then the biculture consortium isolates of thermophilic bacteria were fermented in liquid TMM medium (Thermophilic Minimum Media) and the bioethanol content was measured using a distillation apparatus. The results of this study showed that the six pairs of compatible consortium and MS 9-12 consortium produced the highest bioethanol, namely 1.0003%. Then the biculture consortium isolates of thermophilic bacteria were fermented in liquid TMM medium (Thermophilic Minimum Media) and the bioethanol content was measured using a distillation apparatus. The results of this study showed that the six pairs of compatible consortium and MS 9-12 consortium produced the highest bioethanol, namely 1.0003%. Then the biculture consortium isolates of thermophilic bacteria were fermented in liquid TMM medium (Thermophilic Minimum Media) and the bioethanol content was measured using a distillation apparatus. The results of this study showed that the six pairs of compatible consortium and MS 9-12 consortium produced the highest bioethanol, namely 1.0003%.

An innate granuloma eradicates an environmental pathogen using Gsdmd and Nos2

Granulomas often form around pathogens that cause chronic infections. Here, we discover an innate granuloma model in mice with an environmental bacterium called Chromobacterium violaceum. Granuloma formation not only successfully walls off, but also clears, the infection. The infected lesion can arise from a single bacterium that replicates despite the presence of a neutrophil swarm. Bacterial replication ceases when macrophages organize around the infection and form a granuloma. This granuloma response is accomplished independently of adaptive immunity that is typically required to organize granulomas. The C. violaceum-induced granuloma requires at least two separate defense pathways, gasdermin D and iNOS, to maintain the integrity of the granuloma architecture. This innate granuloma successfully eradicates C. violaceum infection. Therefore, this C. violaceum-induced granuloma model demonstrates that innate immune cells successfully organize a granuloma and thereby resolve infection by an environmental pathogen.

Mechanopathology of biofilm-like Mycobacterium tuberculosis cords

Mycobacterium tuberculosis (Mtb) cultured axenically without detergent forms biofilm-like cords, a clinical identifier of virulence. In lung-on-chip (LoC) and mouse models, cords in alveolar cells contribute to suppression of innate immune signaling via nuclear compression. Thereafter, extracellular cords cause contact-dependent phagocyte death but grow intercellularly between epithelial cells. The absence of these mechanopathological mechanisms explains the greater proportion of alveolar lesions with increased immune infiltration and dissemination defects in cording-deficient Mtb infections. Compression of Mtb lipid monolayers induces a phase transition that enables mechanical energy storage. Agent-based simulations demonstrate that the increased energy storage capacity is sufficient for the formation of cords that maintain structural integrity despite mechanical perturbation. Bacteria in cords remain translationally active despite antibiotic exposure and regrow rapidly upon cessation of treatment. This study provides a conceptual framework for the biophysics and function in tuberculosis infection and therapy of cord architectures independent of mechanisms ascribed to single bacteria.

Microwell-enhanced optical rapid antibiotic susceptibility testing of single bacteria

Bacteria that are resistant to antibiotics present an increasing burden on healthcare. To address this emerging crisis, novel rapid antibiotic susceptibility testing (AST) methods are eagerly needed. Here, we present an optical AST technique that can determine the bacterial viability within 1h down to a resolution of single bacteria. The method is based on measuring intensity fluctuations of a reflected laser focused on a bacterium in reflective microwells. Using numerical simulations, we show that both refraction and absorption of light by the bacterium contribute to the observed signal. By administering antibiotics that kill the bacteria, we show that the variance of the detected fluctuations vanishes within 1 h, indicating the potential of this technique for rapid sensing of bacterial antibiotic susceptibility. We envisage the use of this method for massively parallelizable AST tests and fast detection of drug-resistant pathogens.

Correlating Antibiotic-Induced Dysbiosis to Clostridioides difficile Spore Germination and Host Susceptibility to Infection Using an Ex Vivo Assay.

Antibiotic-induced microbiota disruption and its persistence create conditions for dysbiosis and colonization by opportunistic pathogens, such as those causing Clostridioides difficile (C. difficile) infection (CDI), which is the most severe hospital-acquired intestinal infection. Given the wide differences in microbiota across hosts and in their recovery after antibiotic treatments, there is a need for assays to assess the influence of dysbiosis and its recovery dynamics on the susceptibility of the host to CDI. Germination of C. difficile spores is a key virulence trait for the onset of CDI, which is influenced by the level of primary vs secondary bile acids in the intestinal milieu that is regulated by the microbiota composition. Herein, the germination of C. difficile spores in fecal supernatant from mice that are subject to varying degrees of antibiotic treatment is utilized as an ex vivo assay to predict intestinal dysbiosis in the host based on their susceptibility to CDI, as determined by in vivo CDI metrics in the same mouse model. Quantification of spore germination down to lower detection limits than the colony-forming assay is achieved by using impedance cytometry to count single vegetative bacteria that are identified based on their characteristic electrical physiology for distinction vs aggregated spores and cell debris in the media. As a result, germination can be quantified at earlier time points and with fewer spores for correlation to CDI outcomes. This sets the groundwork for a point-of-care tool to gauge the susceptibility of human microbiota to CDI after antibiotic treatments.

Synergistic principle of catalytic infrared and intense pulsed light for bacteriostasis on green sichuan pepper (Zanthoxylum schinifolium)

A combined method of catalytic infrared (CIR) and intense pulsed light (PL) was investigated to settle a dispute of bacteriostasis on green Sichuan pepper (GSP), and the synergistic principle was elucidated from several aspects. The synergistic bacteriostasis was confirmed first on GSP by the plate counting method. On bacterial cells, leakage of cytoplasmic contents, intracellular protein and DNA breakages were investigated, and the difference between CIR and PL indicated the possibility of synergism. On a single bacterium, the expected synergy was not achieved on the plate but was obtained on GSP, and the bacterial cells treated by the combined method were mainly broken under SEM, indicating that the alliance technology could increase the damage of PL to bacterial cells on the rough surface of GSP. On multiple bacteria, synergy was obtained similarly, and the bacterial community on GSP was investigated with high-throughput sequencing. The community composition on GSP could be changed by the treatments. In conclusion, synergistic bacteriostasis on GSP was achieved by a combined method of CIR and PL, originating from a complementary effect on the microbiome and a promotion of bacteriostatic capacity on rough surfaces. These findings are expected to solve the bacteriostatic difficulty of spices with rough surfaces and have important implications for the development of effective bacteriostatic strategies in food preservation.

Воздействие бовгиалуронидазы азоксимера на бактериальные биопленки в эякуляте пациентов с хроническим простатитом.

Introduction. The use of molecular biological methods in the analysis of bacterial diversity (metataxonomics) of prostate secretion and ejaculate to assess the male microbiota made it possible to identify the bacterial diversity of the microbiota in chronic prostatitis. At the same time, many strains of uropathogens identified in chronic prostatitis show the ability to form biofilms, while there are no generally accepted methods for treating infections caused by bacterial biofilms. Purpose of the study. To study the effect of bovhyaluronidase azoximer in chronic prostatitis, which may be due to the enzymatic action of hyaluronidase on the matrix of bacterial biofilms, which increases the bioavailability of antibiotics, leading to the transition of bacteria into a planktonic state. Material and methods. An electron microscopic study of the ejaculate of 42 patients with chronic prostatitis was performed, of which 32 randomly selected patients received combined antibiotic treatment (4-6 weeks) together with bovhyaluronidase azoxymer (12 weeks) (group I), 10 patients received only antibiotic therapy according to clinical guidelines (group II). On ultrathin sections, the number of bacterial microcolonies and neutrophilic leukocytes per 100 spermatozoa was counted. Results. In the semen of 30 patients, bacterial biofilms with a characteristic morphology were detected: the presence of heterogeneous microorganisms in one microcolony and the presence of a fibrous matrix in which bacteria are immersed. After therapy, in group I, a decrease in the number of bacterial microcolonies, the disappearance of the extracellular matrix, and isolated single bacteria (planktonic state) were detected, in some cases, damage to the bacterial cell wall was detected. In group II quantitative changes in the content of microcolonies and neutrophilic leukocytes were also revealed, however, the morphology of microcolonies in group II did not change. Conclusions. electron microscopy in the study of the ejaculate of patients with chronic prostatitis allows us to reveal the features of the structure of bacterial biofilms. In combined antibiotic therapy together with bovhyaluronidase azoxymer, the biofilm matrix changes and the bacteria transform into a planktonic form.

Measuring prion propagation in single bacteria elucidates a mechanism of loss

Prions are self-propagating protein aggregates formed by specific proteins that can adopt alternative folds. Prions were discovered as the cause of the fatal transmissible spongiform encephalopathies in mammals, but prions can also constitute nontoxic protein-based elements of inheritance in fungi and other species. Prion propagation has recently been shown to occur in bacteria for more than a hundred cell divisions, yet a fraction of cells in these lineages lost the prion through an unknown mechanism. Here, we investigate prion propagation in single bacterial cells as they divide using microfluidics and fluorescence microscopy. We show that the propagation occurs in two distinct modes. In a fraction of the population, cells had multiple small visible aggregates and lost the prion through random partitioning of aggregates to one of the two daughter cells at division. In the other subpopulation, cells had a stable large aggregate localized to the pole; upon division the mother cell retained this polar aggregate and a daughter cell was generated that contained small aggregates. Extending our findings to prion domains from two orthologous proteins, we observe similar propagation and loss properties. Our findings also provide support for the suggestion that bacterial prions can form more than one self-propagating state. We implement a stochastic version of the molecular model of prion propagation from yeast and mammals that recapitulates all the observed single-cell properties. This model highlights challenges for prion propagation that are unique to prokaryotes and illustrates the conservation of fundamental characteristics of prion propagation.

State-of-the-art strategies to prioritize Mycobacterium tuberculosis drug targets for drug discovery using a subtractive genomics approach

Tuberculosis remains one of the causes of death from a single infectious bacterium. The inappropriate use of antibiotics and patients’ non-compliance among other factors drive the emergence of drug-resistant tuberculosis. Multidrug-resistant and extensively drug-resistant strains of tuberculosis pose significant challenges to current treatment regimens, as their reduced efficacy against these strains limits successful patient outcomes. Furthermore, the limited effectiveness and associated toxicity of second-line drugs further compound the issue. Moreover, the scarcity of novel pharmacological targets and the subsequent decline in the number of anti-TB compounds in the drug development pipeline has further hindered the emergence of new therapies. As a result, researchers need to develop innovative approaches to identify potential new anti-TB drugs. The evolution of technology and the breakthrough in omics data allow the use of computational biology approaches, for example, metabolomic analysis to uncover pharmacological targets for structured-based drug design. The role of metabolism in pathogen development, growth, survival, and infection has been established. Therefore, this review focuses on the M. tb metabolic network as a hub for novel target identification and highlights a step-by-step subtractive genomics approach for target prioritization.

Toward Single Bacterium Proteomics.

Bacteria are orders of magnitude smaller than mammalian cells, and while single cell proteomics (SCP) currently detects and quantifies several thousands of proteins per mammalian cell, it is not clear whether conventional SCP methods will be suitable for bacteria. Here we report on the first successful attempt to detect proteins from individual Escherichia coli bacteria, with validation of our findings by comparison with two bacteria samples and bulk proteomics data. Data are available via ProteomeXchange with the identifier PXD043473.

Single bacteria identification with second-harmonic generation in MoS2

Transition-metal dichalcogenides exhibit extraordinary optical nonlinearities, making them promising candidates for advanced photonic applications. Here, we present the microbial control over second-harmonic generation (SHG) in monolayer MoS2 and the identification of single-cell bacteria. Bacteria deposited on monolayer MoS2 induce a change in the SHG signal, in the form of anisotropic polarization responses that depend on the relative orientation of the bacteria with respect to the MoS2 crystallographic direction. The anisotropic enhancement is consistent with the presence of a tensile stress along the lateral direction of bacteria axis; SHG imaging is highly effective in monitoring biomaterial strain as low as 0.1%. We also investigate the ultraviolet-induced removal of single bacteria, through the SHG imaging of MoS2. By monitoring the transient SHG signals, we determine the rupture times for bacteria, which varies noticeably for each species. This allows us to distinguish specific bacteria that share habitats; SHG imaging is useful for label free identification of pathogens at the single cell levels such as E. coli and L. casei. This label-free detection and identification of pathogens at the single-cell level can have a profound impact on the development of diagnostic tools for various applications.

A Dual-Pathogen Mitral Valve Endocarditis Caused by Coxiella burnetii and Streptococcus gordonii-Which Came First?

Infective endocarditis (IE) is still a life-threatening disease with high morbidity and mortality. While usually caused by a single bacterium, poly-microbial infective endocarditis (IE) is rare. Here, we report a (blood-culture-negative) dual pathogen mitral valve IE caused by Coxiella burnetii and Streptococcus gordonii: A 53-year-old woman was presented to an internal medicine department with abdominal pain for further evaluation. Within the diagnostic work up, transthoracic echocardiography (TTE) revealed an irregularly shaped echogenic mass (5 × 13 mm) adherent to the edge of the posterior mitral valve leaflet and protruding into the left atrium. As infected endocarditis was suspected, blood cultures were initially obtained, but they remained negative. Chronic Q fever infection was diagnosed using serologic testing. After the occurrence of cerebral thromboembolic events, the patient was admitted for mitral valve surgery. Intraoperatively, a massively destructed mitral valve with adhering vegetations was noted. Examination of the mitral valve by broad-range bacterial polymerase chain reaction (PCR) and amplicon sequencing confirmed Coxiella burnetii infection and yielded Streptococcus gordonii as the second pathogen. Based on the detailed diagnosis, appropriate antibiotic therapy of both pathogens was initiated, and the patient could be discharged uneventfully on the 11th postoperative day after a successful minimal-invasive mitral valve replacement.

Performance Evaluation of Bacterial Consortia from Low-Permeability Reservoir in Ordos Basin

The combination of strains of different species and genera may enhance the effects of single bacteria, surpass the tolerance upper limit, and optimize the viscosity reduction and degradation. In this study, six strains were isolated in low permeability layers of the Ordos Basin and were combined to verify the effect of the consortium strains. The selected single strains have good emulsifying and viscosity-reducing effects, but their degradation components are different. SC4561 (Bacillus cereus), SC4551 (Bacillus sp.), and H-1 (Brevibacillus sp.) form consortium A, and SC4534 (2) (Bacillus sp.), SC4542 (Bacillus licheniformis), and A-3 (Bacillus licheniformis) form consortium B. The performance of the mixed strains was evaluated by the analysis of change in emulsification rate, crude oil composition, viscosity, and the tolerance (temperature, salinity, and pH) through GC-MS, rotational rheometer, and other methods. The results showed that the temperature tolerance of the consortium strains was improved by 5-7°C. Consortium B had higher emulsibility ( E 24 was higher than 40% in average) and viscosity degradation (above 35%), and the crude oil in consortium B has almost no wall adhesion. The components of crude oil that consortia use were still diverse, including both long- and short-chain hydrocarbons. However, the proportion of long-chain n-alkanes is further reduced compared with that of single bacteria, and the highest ratio was reduced by 23.81% (B-ALL). At the same time, they also had effects on aromatic hydrocarbons with complex structures (phenanthrene and phenanthrene). This research confirms the enhanced effect of consortium bacteria on single bacteria, facilitating the implementation of microbial enhanced oil recovery technology in the future.

Evaluation of dietary single probiotic isolates and probiotic multistrain consortia in growth performance, gut histology, gut microbiota, immune regulation, and infection resistance of Nile tilapia, Oreochromis niloticus, shows superior monostrain performance.

The probiotic potential of a designed bacterial consortia isolated from a competitive exclusion culture originally obtained from the intestinal contents of tilapia juveniles were evaluated on Nile tilapia alevins. The growth performance, intestinal histology, microbiota effects, resistance to Streptococcus agalactiae challenge, and immune response were assessed. In addition, the following treatments were included in a commercial feed: A12+M4+M10 (Lactococcus lactis A12, Priestia megaterium M4, and Priestia sp. M10), M4+M10 (P. megaterium M4, and Priestia sp. M10) and the single bacteria as controls; A12 (L. lactis A12), M4 (P. megaterium M4), M10 (Priestia sp. M10), also a commercial feed without any probiotic addition was included as a control. The results showed that all probiotic treatments improved the growth performance, intestinal histology, and resistance during experimental infection with S. agalactiae in comparison to the control fish. Also, the administration of probiotics resulted in the modulation of genes associated with the innate and adaptive immune systems that were non-dependent on microbial colonization. Surprisingly, L. lactis A12 alone induced benefits in fish compared to the microbial consortia, showing the highest increase in growth rate, survival during experimental infection with S. agalactiae, increased intestinal fold length, and the number of differentially expressed genes. Lastly, we conclude that a competitive exclusion culture is a reliable source of probiotics, and monostrain L. lactis A12 has comparable or even greater probiotic potential than the bacterial consortia.

Intracellular Dynamics-Resolved Label-Free Scattering Reveals Real-Time Metabolism of Single Bacteria.

Nanoscopic investigation of bacterial cells is essential to reveal their physiological status, impacting all cellular functions. Currently, this requires labeled probes or targeted staining procedures. Herein, we report a new bacterial feature, intracellular dynamics-resolved Rayleigh scattering (IDRS), that visualizes spatiotemporal cytoplasmic transitions in unlabeled bacteria and characterizes their real-time physiological status in 10 s. From single-bacterium IDRS signals, we discovered unique spatial patterns and their multiple transitions in Gram-negative and Gram-positive bacteria. The magnitude of IDRS signal variation highly correlated with the metabolic status of bacteria, differentiating persistent subpopulations. This is also the first report demonstrating distinct real-time metabolic conditions of unlabeled drug-resistant bacteria that are exposed to different doses of antibiotics. Our strategy opens up a way to simultaneously trace in situ metabolic and antibiotic resistance statuses, which can be applied in single-cell level control of bacterial metabolism and efficacy with a heterogeneous nature.

Uropathogens and their Culture Sensitivity Pattern in Children with Urinary Tract Infection.

Objective: To determine the frequency of bacteria causing Urinary Tract infections and their susceptibility to antibiotics in children of Sialkot.
 Study Design: Cross-sectional study.
 Place and Duration of Study: Department of Pediatrics Islam Teaching Hospital, Children Complex Hospital, and Islam Central Hospital, Sialkot Pakistan, from Jan to Dec 2020.
 Methodology: All patients presenting with Urinary Tract infections, aged one month to 15 years were included in the study. Inclusion criteria were clinical suspicion of Urinary Tract infections and positive urine culture of a single bacterium. Antibiotic susceptibility was performed on all culture-positive samples. 
 Results: A total of 300 children were included, but 248 fulfilled the criteria of culture-positive Urinary Tract infections. Fiftytwo children were excluded as they had non-pathogen growths, multi-organisms or were already on antibiotics. Gramnegative bacilli were most frequently isolated, accounting for 236(95.2%), whereas Gram-positive cocci comprised only 12 (4.8%) of cases. E. coli was the most frequent isolate among gram-negative rods, followed by Klebsiella, Proteus and Pseudomonas. All gram-negative rods were sensitive to Imipenem, whereas most were resistant to Ampicillin and TMP-SMX. Gram-positive cocci were sensitive to Vancomycin, Linezolid, Meropenem and Tazobactam.
 Conclusion: Increasing resistance of uropathogens to commonly prescribed antibiotics is highly alarming. Therefore, the strategy of empirical treatment of Urinary Tract infections in children should be reevaluated based on regional studies.

Live-cell imaging reveals single-cell and population-level infection strategies of Listeria monocytogenes in macrophages.

Pathogens have developed intricate strategies to overcome the host's innate immune responses. In this paper we use live-cell microscopy with a single bacterium resolution to follow in real time interactions between the food-borne pathogen L. monocytogenes and host macrophages, a key event controlling the infection in vivo. We demonstrate that infection results in heterogeneous outcomes, with only a subset of bacteria able to establish a replicative invasion of macrophages. The fate of individual bacteria in the same host cell was independent from the host cell and non-cooperative, being independent from co-infecting bacteria. A higher multiplicity of infection resulted in a reduced probability of replication of the overall bacterial population. By use of internalisation assays and conditional probabilities to mathematically describe the two-stage invasion process, we demonstrate that the higher MOI compromises the ability of macrophages to phagocytose bacteria. We found that the rate of phagocytosis is mediated via the secreted Listeriolysin toxin (LLO), while the probability of replication of intracellular bacteria remained constant. Using strains expressing fluorescent reporters to follow transcription of either the LLO-encoding hly or actA genes, we show that replicative bacteria exhibited higher PrfA regulon expression in comparison to those bacteria that did not replicate, however elevated PrfA expression per se was not sufficient to increase the probability of replication. Overall, this demonstrates a new role for the population-level, but not single cell, PrfA-mediated activity to regulate outcomes of host pathogen interactions.

Enhancing food waste reduction efficiency and high-value biomass production in Hermetia illucens rearing through bioaugmentation with gut bacterial agent

The black soldier fly (BSF) rearing technology has been a promising bioconversion method for food waste (FW) disposal. However, when used independently, it currently only achieves low efficiency and biomass transformation rates (BTR). This study screened and identified two strains of gut beneficial bacteria, Bacillus cereus and Bacterium YC-LK-LKJ45. The efficiency of a complex culture formulated by these strains was investigated, focusing on enhancing FW reduction and high-value biomass production during the rearing of BSF larvae. The coculture agent group (G1–10%, with two strains in 1:1 volume ratio at a 10 % dosage) exhibited higher larval yield (627.67 g·kg−1), BTR (47.90 %), FW reduction efficiency (80.67 %), and total protein and fat yield (261.99 g·kg−1and 46.24 g·kg−1) compared to the control and the monoculture agent group (which added a single gut beneficial bacteria agent, either Bacillus cereus or Bacterium YC-LK-LKJ45). The bacterial agent altered the richness and diversity of the gut microbial community of BSF, increasing the relative abundance of beneficial bacteria such as Bacillus, Oceano bacillus, and Akkermansia, while decreasing pathogenic bacteria, such as Acinetobacter and Escherichia-Shigella. Structural equation model quantification revealed that α-diversity (λ = 0.897, p < 0.001) and BTR (λ = 0.747, p < 0.001) are crucial drivers for enhancing high-value biomass during bioaugmentation rearing. This investigation provides a theoretical framework for the effective management of food waste using BSF, enhancing its decomposition and transformation into higher-value biomass.

Application of Nanopore Sequencing in the Diagnosis and Treatment of Pulmonary Infections.

This review provides an in-depth discussion of the development, principlesand utility of nanopore sequencing technology and its diverse applications in the identification of various pulmonary pathogens. We examined the emergence and advancements of nanopore sequencing as a significant player in this field. We illustrate the challenges faced in diagnosing mixed infections and further scrutinize the use of nanopore sequencing in the identification of single pathogens, including viruses (with a focus on its use in epidemiology, outbreak investigation, and viral resistance), bacteria (emphasizing 16S targeted sequencing, rare bacterial lung infections, and antimicrobial resistance studies), fungi (employing internal transcribed spacer sequencing), tuberculosis, and atypical pathogens. Furthermore, we discuss the role of nanopore sequencing in metagenomics and its potential for unbiased detection of all pathogens in a clinical setting, emphasizing its advantages in sequencing genome repeat areas and structural variant regions. We discuss the limitations in dealing with host DNA removal, the inherent high error rate of nanopore sequencing technology, along with the complexity of operation and processing,while acknowledging the possibilities provided by recent technological improvements. We compared nanopore sequencing with the BioFire system, a rapid molecular diagnostic system based on polymerase chain reaction. Although the BioFire system serves well for the rapid screening of known and common pathogens, it falls short in the identification of unknown or rare pathogens and in providing comprehensive genome analysis. As technological advancements continue, it is anticipated that the role of nanopore sequencing technology in diagnosing and treating lung infections will become increasingly significant.

Antimicrobial Activity of the Nanoparticle Form of Greens (Lemon, Black Seeds or Flax) with Silver on Drug-resistant Human Pathogens.

Synthesizing a green source that has antimicrobial activity in nanoparticles is a novel and exciting approach to pharmaceutical science with promising results. Green-silver nanoparticles (G-AgNPs) were evaluated for their antimicrobial action on drugresistant pathogens. Lemon, black seeds, and flax were selected as green sources to synthesize nanoparticles formed with silver. Physical and chemical characteristics of these preparations were identified. The antimicrobial activities of the prepared compounds against drug-resistant clinical isolates of seven bacteria and five fungi were identified by disk diffusion and dilution methods. The nanoparticle characteristics were confirmed by physical and chemical measurements. Lemon extract with silver nanoparticles (L-AgNP) showed more antimicrobial action, particularly on Gram-positive bacteria and Candida albicans. Silver nanoparticles with black seeds (B-AgNP) and flax (F-AgNP) had only antibacterial effects on a single bacterium (Enterobacter cloacae). Escherichia coli, Staphylococcus aureus, and two fungi, Candida glabrata and Candida utilis, showed resistance to all nanoparticles from plants. Lemon with silver nanoparticle is an effective plant product for use against various drugresistant species of human pathogens. Further pharmaceutical studies are required to verify the suitability of this form of the drug for human use. Another plant is recommended for testing against the most resistant strains of pathogens.