An effective and rapidly degradable disinfectant from disinfection byproducts.

Chloroxylenol is a worldwide commonly used disinfectant. The massive consumption and relatively high chemical stability of chloroxylenol have caused eco-toxicological threats in receiving waters. We noticed that chloroxylenol has a chemical structure similar to numerous halo-phenolic disinfection byproducts. Solar detoxification of some halo-phenolic disinfection byproducts intrigued us to select a rapidly degradable chloroxylenol alternative from them. In investigating antimicrobial activities of disinfection byproducts, we found that 2,6-dichlorobenzoquinone was 9.0-22 times more efficient than chloroxylenol in inactivating the tested bacteria, fungi and viruses. Also, the developmental toxicity of 2,6-dichlorobenzoquinone to marine polychaete embryos decreased rapidly due to its rapid degradation via hydrolysis in receiving seawater, even without sunlight. Our work shows that 2,6-dichlorobenzoquinone is a promising disinfectant that well addresses human biosecurity and environmental sustainability. More importantly, our work may enlighten scientists to exploit the slightly alkaline nature of seawater and develop other industrial products that can degrade rapidly via hydrolysis in seawater.

Combat phytopathogenic bacteria employing Argirium-SUNCs: limits and perspectives.

Bacterial plant diseases are difficult to control as the durability of deployed control measures is thwarted by continuous and rapid changing of bacterial populations. Although application of copper compounds to plants is the most widespread and inexpensive control measure, it is often partially efficacious for the frequent appearance of copper-resistant bacterial strains and it is raising concerns for the harmful effects of copper on environment and human health. Consequently, European Community included copper compounds in the list of substances candidates for substitution. Nanotechnologies and the application of nanoparticles seem to respond to the need to find new very effective and durable measures. We believe that Argirium-SUNCs®, silver ultra nanoclusters with an average size of 1.79 nm and characterized by rare oxidative states (Ag2+/3+), represent a valid candidate as a nano-bactericide in the control of plant bacterial diseases. Respect to the many silver nanoparticles described in the literature, Argirium-SUNCs have many strengths due to the reproducibility of the synthesis method, the purity and the stability of the preparation, the very strong (less than 1 ppm) antimicrobial, and anti-biofilm activities. In this mini-review, we provide information on this nanomaterial and on the possible application in agriculture. KEY POINTS: • Argirium-SUNCs have strong antimicrobial activities against phytopathogenic bacteria. • Argirium-SUNCs are a possible plant protection product. • Argirium-SUNCs protect tomato plants against bacterial speck disease.

The unexpected effect of the compound microbial agent NP-M2 on microbial community dynamics in a nonylphenol-contaminated soil: the self-stability of soil ecosystem.

Background: Nonylphenol (NP) is widely recognized as a crucial environmental endocrine-disrupting chemical and persistent toxic substance. The remediation of NP-contaminated sites primarily relies on biological degradation. Compound microbial products, as opposed to pure strains, possess a greater variety of metabolic pathways and can thrive in a wider range of environmental conditions. This characteristic is believed to facilitate the synergistic degradation of pollutants. Limited research has been conducted to thoroughly examine the potential compatibility of compound microbial agents with indigenous microflora, their ability to function effectively in practical environments, their capacity to enhance the dissipation of NP, and their potential to improve soil physicochemical and biological characteristics. Methods: In order to efficiently eliminate NP in contaminated soil in an eco-friendly manner, a simulation study was conducted to investigate the impact of bioaugmentation using the functional compound microbial agent NP-M2 at varying concentrations (50 and 200 mg/L) on the dynamics of the soil microbial community. The treatments were set as follows: sterilized soil with 50 mg/kg NP (CK50) or 200 mg/kg NP (CK200); non-sterilized soil with 50 mg/kg NP (TU50) or 200 mg/kg NP (TU200); non-sterilized soil with the compound microbial agent NP-M2 at 50 mg/kg NP (J50) or 200 mg/kg NP (J200). Full-length 16S rRNA analysis was performed using the PacBio Sequel II platform. Results: Both the indigenous microbes (TU50 and TU200 treatments) and the application of NP-M2 (J50 and J200 treatments) exhibited rapid NP removal, with removal rates ranging from 93% to 99%. The application of NP-M2 further accelerated the degradation rate of NP for a subtle lag period. Although the different treatments had minimal impacts on the soil bacterial α-diversity, they significantly altered the ß-diversity and composition of the bacterial community. The dominant phyla were Proteobacteria (35.54%-44.14%), Acidobacteria (13.55%-17.07%), Planctomycetes (10.78%-11.42%), Bacteroidetes (5.60%-10.74%), and Actinobacteria (6.44%-8.68%). The core species were Luteitalea_pratensis, Pyrinomonas_methylaliphatogenes, Fimbriiglobus_ruber, Longimicrobium_terrae, and Massilia_sp003590855. The bacterial community structure and taxon distribution in polluted soils were significantly influenced by the activities of soil catalase, sucrase, and polyphenol oxidase, which were identified as the major environmental factors. Notably, the concentration of NP and, to a lesser extent, the compound microbial agent NP-M2 were found to cause major shifts in the bacterial community. This study highlights the importance of conducting bioremediation experiments in conjunction with microbiome assessment to better understand the impact of bioaugmentation/biostimulation on the potential functions of complex microbial communities present in contaminated soils, which is essential for bioremediation success.

Bacterial Aggregation in Cerebral Spinal Fluid: The Extent it Occurs and the Clinical Ramifications.

Bacteria can form aggregates in synovial fluid that are resistant to antibiotics, but the ability to form aggregates in cerebral spinal fluid (CSF) is poorly defined. Consequently, the aims of this study were to assess the propensity of four bacterial species to form aggregates in CSF under various conditions. To achieve these aims, bacteria were added to CSF in microwell plates and small flasks at static and different dynamic conditions with the aid of an incubating shaker. The aggregates that formed were assessed for antibiotic resistance and the ability of tissue plasminogen activator (TPA) to disrupt these aggregates and reduce the number of bacteria present when used with antibiotics. The results of this study show that under dynamic conditions all four bacteria species formed aggregates that were resistant to high concentrations of antibiotics. Yet with static conditions, no bacteria formed aggregates and when the CSF volume was increased, only Staphylococcus aureus formed aggregates. Interestingly, the aggregates that formed were easily dispersed by TPA and significant (p < 0.005) decreases in colony-forming units were seen when a combination of TPA and antibiotics were compared to antibiotics alone. These findings have clinical significance in that they show bacterial aggregation does not habitually occur in central nervous system infections, but rather occurs under specific conditions. Furthermore, the use of TPA combined with antibiotics may be advantageous in recalcitrant central nervous system infections and this provides a pathophysiological explanation for an unusual finding in the CLEAR III clinical trial.

Characterization of the intestinal microbiota in MSM with HIV infection.

BACKGROUND: HIV-infected persons demonstrate notable disturbances in their intestinal microbiota; however, the impact of intestinal microbiota on HIV susceptibility in men who have sex with men (MSM), as well as the effects of HIV and antiretroviral therapy (ART) on their gut microbiota, remains under active study. Thus, our research focuses on clarifying the distinctions in intestinal microbiota composition among uninfected MSM and non-MSM healthy controls, investigating the alterations in early-stage intestinal microbial communities following HIV infection, and assessing how ART affects the intestinal microbiota. METHODS: This study enrolled four participant groups: uninfected MSM, Recent HIV-1 infection (RHI) MSM, MSM on ART, and non-MSM healthy controls, with 30 individuals in each group. We utilized 16S ribosomal DNA (16S rDNA) amplicon sequencing to analyze fecal microbiota and employed Luminex multiplex assays to measure plasma markers for microbial translocation (LBP, sCD14) and the inflammatory marker CRP. FINDINGS: Comparing uninfected MSM to non-MSM healthy controls, no substantial variances were observed in α and ß diversity. Uninfected MSM had higher average relative abundances of Bacteroidetes, Prevotella, and Alloprevotella, while Bacteroides, Firmicutes, and Faecalibacterium had lower average relative abundances. MSM on ART had lower intestinal microbiota diversity than RHI MSM and uninfected MSM. In MSM on ART, Megasphaera and Fusobacterium increased, while Faecalibacterium and Roseburia decreased at genus level. Additionally, treatment with a non-nucleoside reverse transcriptase inhibitor (NNRTI) led to significant alterations in intestinal microbiota diversity and composition compared to RHI MSM. The random forest model showed that HIV infection biomarkers effectively distinguished between newly diagnosed HIV-infected MSM and HIV-negative MSM, with an ROC AUC of 76.24% (95% CI: 61.17-91.31%). CONCLUSIONS: MSM showed early intestinal microbiota imbalances after new HIV infection. MSM on ART experienced worsened dysbiosis, indicating a combined effect of HIV and ART. NNRTI-based treatment notably changed intestinal microbiota, suggesting a potential direct impact of NNRTI drugs on intestinal microbiota.

Chitosan/Alginate-Based Nanoparticles for Antibacterial Agents Delivery.

Nanoparticle systems integrating alginate and chitosan emerge as a promising avenue to tackle challenges in leveraging the potency of pharmacological active agents. Owing to their intrinsic properties as polysaccharides, alginate and chitosan, exhibit remarkable biocompatibility, rendering them conducive to bodily integration. By downsizing drug particles to the nano-scale, the system enhances drug solubility in aqueous environments by augmenting surface area. Additionally, the system orchestrates extended drug release kinetics, aligning well with the exigencies of chronic drug release requisite for antibacterial therapeutics. A thorough scrutiny of existing literature underscores a wealth of evidence supporting the utilization of the alginate-chitosan nanoparticle system for antibacterial agent delivery. Literature reviews present abundant evidence of the utilization of nanoparticle systems based on a combination of alginate and chitosan for antibacterial agent delivery. Various experiments demonstrate enhanced antibacterial efficacy, including an increase in the inhibitory zone diameter, improvement in the minimum inhibitory concentration, and an enhancement in the bacterial reduction rate. This enhancement in efficacy occurs due to mechanisms involving increased solubility resulting from particle size reduction, prolonged release effects, and enhanced selectivity towards bacterial cell walls, stemming from ionic interactions between positively charged particles and teichoic acid on bacterial cell walls. However, clinical studies remain limited, and there are currently no marketed antibacterial drugs utilizing this system. Hence, expediting clinical efficacy validation is crucial to maximize its benefits promptly.

Chemical compositions of Eucalyptus sp. Essential oils and the evaluation of their combinations as a promising treatment against ear bacterial infections.

BACKGROUND: The chemical composition and biological activities of Eucalyptus essential oils (EOs) have been documented in numerous studies against multiple infectious diseases. The antibacterial activity of individual Eucalyptus EOs against strains that cause ear infections was investigated in our previous study. The study's antibacterial activity was promising, which prompted us to explore this activity further with EO blends. METHODS: We tested 15 combinations (9 binary combinations and 6 combinations of binary combinations) of Eucalyptus EOs extracted by hydrodistillation from eight Tunisian Eucalyptus species dried leaves against six bacterial strains responsible for ear infections: three bacterial isolates (Haemophilus influenzae, Haemophilus parainfluenzae, and Klebsiella pneumoniae) and three reference bacteria strains (Pseudomonas aeruginosa, ATTC 9027; Staphylococcus aureus, ATCC 6538; and Escherichia coli, ATCC 8739). The EOs were analyzed using GC/FID and GC/MS. The major compounds, as well as all values obtained from the bacterial growth inhibition assay, were utilized for statistical analysis. RESULTS: The antibacterial activity of the EO blends exhibited significant variation within Eucalyptus species, bacterial strains, and the applied methods. Principal component analysis (PCA) and hierarchical cluster analysis (HCA), based on the diameters of the inhibition zone, facilitated the identification of two major groups and ten subgroups based on the level of antibacterial activity. The highest antibacterial activity was observed for the mixture of EOs extracted from E. panctata, E. accedens, and E. cladoclayx (paac) as well as E. panctata, E. wandoo, E. accedens, and E. cladoclayx (pwac) using the disc diffusion method. Additionally, significant activity was noted with EOs extracted from E. panctata, E. wandoo (pw) and E. panctata, E. accedens (pa) using the broth microdilution method. CONCLUSION: Our findings suggest that certain EO combinations (paac, pwac, pw, and pa) could be considered as potential alternative treatment for ear infections due to their demonstrated highly promising antibacterial activities.

Characterizations of multi-kingdom gut microbiota in immune checkpoint inhibitor-treated hepatocellular carcinoma.

BACKGROUND: The association between gut bacteria and the response to immune checkpoint inhibitors (ICI) in hepatocellular carcinoma (HCC) has been studied; however, multi-kingdom gut microbiome alterations and interactions in ICI-treated HCC cohorts are not fully understood. METHODS: From November 2018 to April 2022, patients receiving ICI treatment for advanced HCC were prospectively enrolled. Herein, we investigated the multi-kingdom microbiota characterization of the gut microbiome, mycobiome, and metabolome using metagenomic, ITS2, and metabolomic data sets of 80 patients with ICI-treated HCC. RESULTS: Our findings demonstrated that bacteria and metabolites differed significantly between the durable clinical benefit (DCB) and non-durable clinical benefit (NDB) groups, whereas the differences were smaller for fungi. The overall diversity of bacteria and fungi before treatment was higher in the DCB group than in the NDB group, and the difference in diversity began to change with the use of immunotherapy after 6-8 weeks. We also explored the alterations of gut microbes in the DCB and NDB groups, established 18 bacterial species models as predictive biomarkers for predicting whether immunotherapy is of sustained benefit (area under the curve=75.63%), and screened two species of bacteria (Actinomyces_sp_ICM47, and Senegalimassilia_anaerobia) and one metabolite (galanthaminone) as prognostic biomarkers for predicting survival in patients with HCC treated with ICI. CONCLUSIONS: In this study, the status and characterization of the multi-kingdom microbiota, including gut bacteria, fungi, and their metabolites, were described by multiomics sequencing for the first time in patients with HCC treated with ICI. Our findings demonstrate the potential of bacterial taxa as predictive biomarkers of ICI clinical efficacy, and bacteria and their metabolites as prognostic biomarkers.

Antibacterial Potential of Non-Tailed Icosahedral Phages Alone and in Combination with Antibiotics.

Non-tailed icosahedral phages belonging to families Fiersviridae (phages MS2 and Qbeta), Tectiviridae (PRD1) and Microviridae (phiX174) have not been considered in detail so far as potential antibacterial agents. The aim of the study was to examine various aspects of the applicability of these phages as antibacterial agents. Antibacterial potential of four phages was investigated via bacterial growth and biofilm formation inhibition, lytic spectra determination, and phage safety examination. The phage phiX174 was combined with different classes of antibiotics to evaluate potential synergistic interactions. In addition, the incidence of phiX174-insensitive mutants was analyzed. The results showed that only phiX174 out of four phages tested against their corresponding hosts inhibited bacterial growth for > 90% at different multiplicity of infection and that only this phage considerably prevented biofilm formation. Although all phages show the absence of potentially undesirable genes, they also have extremely narrow lytic spectra. The synergism was determined between phage phiX174 and ceftazidime, ceftriaxone, ciprofloxacin, macrolides, and chloramphenicol. It was shown that the simultaneous application of agents is more effective than successive treatment, where one agent is applied first. The analysis of the appearance of phiX174 bacteriophage-insensitive mutants showed that mutations occur with a frequency of 10-3. The examined non-tailed phages have a limited potential for use as antibacterial agents, primarily due to a very narrow lytic spectrum and the high frequency of resistant mutants appearance, but Microviridae can be considered in the future as biocontrol agents against susceptible strains of E. coli in combinations with conventional antimicrobial agents.

Effect of household pipe materials on formation and chlorine resistance of the early-stage biofilm: various interspecific interactions exhibited by the same microbial biofilm in different pipe materials.

Microbial community biofilm exists in the household drinking water system and would pose threat to water quality. This paper explored biofilm formation and chlorination resistance of ten dual-species biofilms in three typical household pipes (stainless steel (SS), polypropylene random (PPR), and copper), and investigated the role of interspecific interaction. Biofilm biomass was lowest in copper pipes and highest in PPR pipes. A synergistic or neutralistic relationship between bacteria was evident in most biofilms formed in SS pipes, whereas four groups displayed a competitive relationship in biofilms formed in copper pipe. Chlorine resistance of biofilms was better in SS pipes and worse in copper pipes. It may be helped by interspecific relationships, but was more dependent on bacteria and resistance mechanisms such as more stable extracellular polymeric substance. The corrosion sites may also protect bacteria from chlorination. The findings provide useful insights for microbial control strategies in household drinking water systems.

Grape seed extract prevents oestrogen deficiency-induced bone loss by modulating the gut microbiota and metabolites.

Proanthocyanidin-rich grape seed extract (GSE) has been shown to have the potential to protect bones, although the underlying mechanism remains unknown. The current study aims to explore GSE's preventive and therapeutic impact on bone loss induced by oestrogen deficiency and the underlying mechanism through the gut microbiota (GM) and metabolomic responses. In oestrogen-deficient ovariectomized (OVX) mice, GSE ameliorated bone loss by inhibiting the expansion of bone marrow adipose tissue (BMAT), restoring BMAT lipolysis and promoting bone formation. GSE regulated OVX-induced GM dysbiosis by reducing the abundance of opportunistic pathogenic bacteria, such as Alistipes, Turicibacter and Romboutsia, while elevating the abundance of beneficial bacteria, such as Bifidobacterium. The modified GM primarily impacted lipid and amino acid metabolism. Furthermore, the serum metabolites of GSE exhibited a significant enrichment in lipid metabolism. In summary, GSE shows potential as a functional food for preventing oestrogen deficiency-induced bone loss by modulating GM and metabolite-mediated lipid metabolism.

The effect of daily usage of Listerine Cool Mint mouthwash on the oropharyngeal microbiome: a substudy of the PReGo trial.

Introduction. ListerineÒ is a bactericidal mouthwash widely used to prevent oral health problems such as dental plaque and gingivitis. However, whether it promotes or undermines a healthy oral microbiome is unclear.Hypothesis/Gap Statement. We hypothesized that the daily use of Listerine Cool Mint would have a significant impact on the oropharyngeal microbiome.Aim. We aimed to assess if daily usage of Listerine Cool Mint influenced the composition of the pharyngeal microbiome.Methodology. The current microbiome substudy is part of the Preventing Resistance in Gonorrhoea trial. This was a double-blind single-centre, crossover, randomized controlled trial of antibacterial versus placebo mouthwash to reduce the incidence of gonorrhoea/chlamydia/syphilis in men who have sex with men (MSM) taking HIV pre-exposure prophylaxis (PrEP). Fifty-nine MSM taking HIV PrEP were enrolled. In this crossover trial, participants received 3 months of daily Listerine followed by 3 months of placebo mouthwash or vice versa. Oropharyngeal swabs were taken at baseline and after 3 months use of each mouthwash. DNA was extracted for shotgun metagenomic sequencing (Illumina Inc.). Non-host reads were taxonomically classified with MiniKraken and Bracken. The alpha and beta diversity indices were compared between baseline and after each mouthwash use. Differentially abundant bacterial taxa were identified using ANOVA-like differential expression analysis.Results. Streptococcus was the most abundant genus in most samples (n = 103, 61.7 %) with a median relative abundance of 31.5% (IQR 20.6-44.8), followed by Prevotella [13.5% (IQR 4.8-22.6)] and Veillonella [10.0% (IQR 4.0-16.8)]. Compared to baseline, the composition of the oral microbiome at the genus level (beta diversity) was significantly different after 3 months of Listerine (P = 0.006, pseudo-F = 2.29) or placebo (P = 0.003, pseudo-F = 2.49, permutational multivariate analysis of variance) use. Fusobacterium nucleatum and Streptococcus anginosus were significantly more abundant after Listerine use compared to baseline.Conclusion. Listerine use was associated with an increased abundance of common oral opportunistic bacteria previously reported to be enriched in periodontal diseases, oesophageal and colorectal cancer, and systemic diseases. These findings suggest that the regular use of Listerine mouthwash should be carefully considered.

Multiple use of preservative-free single dose unit dexamethasone 0.1% eye drops is safe within 24 hours.

BACKGROUND: Unpreserved single-dose unit (SDU) eye drops are commonly used to avoid benzalkonium chloride-related toxicity. Although intended for single use, many patients report off-label repeated use of SDUs over a prolonged period. We investigated whether repeated use of dexamethasone 0.1% SDUs in the same patient increases the bacterial contamination rate. METHODS: We prospectively enrolled patients scheduled for inpatient corneal and glaucoma surgery receiving dexamethasone 0.1% SDU four times per day from the same vial. To assess contamination rates, one drop from the vial was cultured immediately after opening the SDU (t0), 10 hours later after four drop applications (t10) and 24 hours after opening without further drop applications (t24). Conjunctival swabs were taken before and after drop application. Contamination rate was assessed with a standard clinical culturing protocol without introducing a positive control. RESULTS: 110 eyes of 109 patients were evaluated. Drops collected immediately after opening the SDU (t0) were contaminated in 9/110 cultures (8.1%). At t10, 13/110 cultures were contaminated (11.8%; p=0.267) and 11/110 at t24 (10.0%; t24 vs t0; p=1.00). In 5 of 21 cases of contaminated drops at t10 and/or t24, the same isolates were cultured from the initial conjunctival swab and the SDU. In three cases, the same bacterial species was found in consecutive samples. CONCLUSION: The contamination rate of the SDU did not increase after multiple use within 24 hours. Contamination from fingertip flora was more likely than from ocular surface flora. Reuse of dexamethasone 0.1% SDU in the same patient within 24 hours appears to be safe.

Gut resistome linked to sexual preference and HIV infection.

BACKGROUND: People living with HIV (PLWH) are at increased risk of acquisition of multidrug resistant organisms due to higher rates of predisposing factors. The gut microbiome is the main reservoir of the collection of antimicrobial resistance determinants known as the gut resistome. In PLWH, changes in gut microbiome have been linked to immune activation and HIV-1 associated complications. Specifically, gut dysbiosis defined by low microbial gene richness has been linked to low Nadir CD4 + T-cell counts. Additionally, sexual preference has been shown to strongly influence gut microbiome composition in PLWH resulting in different Prevotella or Bacteroides enriched enterotypes, in MSM (men-who-have-sex-with-men) or no-MSM, respectively. To date, little is known about gut resistome composition in PLWH due to the scarcity of studies using shotgun metagenomics. The present study aimed to detect associations between different microbiome features linked to HIV-1 infection and gut resistome composition. RESULTS: Using shotgun metagenomics we characterized the gut resistome composition of 129 HIV-1 infected subjects showing different HIV clinical profiles and 27 HIV-1 negative controls from a cross-sectional observational study conducted in Barcelona, Spain. Most no-MSM showed a Bacteroides-enriched enterotype and low microbial gene richness microbiomes. We did not identify differences in resistome diversity and composition according to HIV-1 infection or immune status. However, gut resistome was more diverse in MSM group, Prevotella-enriched enterotype and gut micorbiomes with high microbial gene richness compared to no-MSM group, Bacteroides-enriched enterotype and gut microbiomes with low microbial gene richness. Additionally, gut resistome beta-diversity was different according to the defined groups and we identified a set of differentially abundant antimicrobial resistance determinants based on the established categories. CONCLUSIONS: Our findings reveal a significant correlation between gut resistome composition and various host variables commonly associated with gut microbiome, including microbiome enterotype, microbial gene richness, and sexual preference. These host variables have been previously linked to immune activation and lower Nadir CD4 + T-Cell counts, which are prognostic factors of HIV-related comorbidities. This study provides new insights into the relationship between antibiotic resistance and clinical characteristics of PLWH.

Environmental microbiome diversity and stability is a barrier to antimicrobial resistance gene accumulation.

When antimicrobial resistant bacteria (ARB) and genes (ARGs) reach novel habitats, they can become part of the habitat's microbiome in the long term if they are able to overcome the habitat's biotic resilience towards immigration. This process should become more difficult with increasing biodiversity, as exploitable niches in a given habitat are reduced for immigrants when more diverse competitors are present. Consequently, microbial diversity could provide a natural barrier towards antimicrobial resistance by reducing the persistence time of immigrating ARB and ARG. To test this hypothesis, a pan-European sampling campaign was performed for structured forest soil and dynamic riverbed environments of low anthropogenic impact. In soils, higher diversity, evenness and richness were significantly negatively correlated with relative abundance of >85% of ARGs. Furthermore, the number of detected ARGs per sample were inversely correlated with diversity. However, no such effects were present in the more dynamic riverbeds. Hence, microbiome diversity can serve as a barrier towards antimicrobial resistance dissemination in stationary, structured environments, where long-term, diversity-based resilience against immigration can evolve.

Short-term culture for rapid identification by mass spectrometry and automated antimicrobial susceptibility testing from positive bottles.

BACKGROUND: Early and appropriate antibiotic treatment improves the clinical outcome of patients with sepsis. There is an urgent need for rapid identification (ID) and antimicrobial susceptibility testing (AST) of bacteria that cause bloodstream infection (BSI). Rapid ID and AST can be achieved by short-term incubation on solid medium of positive blood cultures using MALDI-TOF mass spectrometry (MS) and the BD M50 system. The purpose of this study is to evaluate the performance of rapid method compared to traditional method. METHODS: A total of 124 mono-microbial samples were collected. Positive blood culture samples were short-term incubated on blood agar plates and chocolate agar plates for 5 ∼ 7 h, and the rapid ID and AST were achieved through Zybio EXS2000 MS and BD M50 System, respectively. RESULTS: Compared with the traditional 24 h culture for ID, this rapid method can shorten the cultivation time to 5 ∼ 7 h. Accurate organism ID was achieved in 90.6% of Gram-positive bacteria (GP), 98.5% of Gram-negative bacteria (GN), and 100% of fungi. The AST resulted in the 98.5% essential agreement (EA) and 97.1% category agreements (CA) in NMIC-413, 99.4% EA and 98.9% CA in PMIC-92, 100% both EA and CA in SMIC-2. Besides, this method can be used for 67.2% (264/393) of culture bottles during routine work. The mean turn-around time (TAT) for obtaining final results by conventional method is approximately 72.6 ± 10.5 h, which is nearly 24 h longer than the rapid method. CONCLUSIONS: The newly described method is expected to provide faster and reliable ID and AST results, making it an important tool for rapid management of blood cultures (BCs). In addition, this rapid method can be used to process most positive blood cultures, enabling patients to receive rapid and effective treatment.

Detection of Vancomycin Resistant Genes in Intrinsically Antibiotic Resistant Bacteria from the Gut Microbiota of Indonesian Individuals.

Background: Antibiotic resistance is a global public health concern that has been exacerbated by the overuse and misuse of antibiotics, leading to the emergence of resistant bacteria. The gut microbiota, often influenced by antibiotic usage, plays a crucial role in overall health. Therefore, this study aimed to investigate the prevalence of antibiotic resistant genes in the gut microbiota of Indonesian coastal and highland populations, as well as to identify vancomycin-resistant bacteria and their resistant genes. Methods: Stool samples were collected from 22 individuals residing in Pacet, Mojokerto, and Kenjeran, Surabaya Indonesia in 2022. The read count of antibiotic resistant genes was analyzed in the collected samples, and the bacterium concentration was counted by plating on the antibiotic-containing agar plate. Vancomycin-resistant strains were further isolated, and the presence of vancomycin-resistant genes was detected using a multiplex polymerase chain reaction (PCR). Results: The antibiotic resistant genes for tetracycline, aminoglycosides, macrolides, beta-lactams, and vancomycin were found in high frequency in all stool samples (100%) of the gut microbiota. Meanwhile, those meant for chloramphenicol and sulfonamides were found in 86% and 16% of the samples, respectively. Notably, vancomycin-resistant genes were found in 16 intrinsically resistant Gram-negative bacterial strains. Among the detected vancomycin-resistant genes, vanG was the most prevalent (27.3%), while vanA was the least prevalent (4.5%). Conclusion: The presence of multiple vancomycin resistance genes in intrinsically resistant Gram-negative bacterial strains demonstrated the importance of the gut microbiota as a reservoir and hub for the horizontal transfer of antibiotic resistant genes.

Use of cerrado plants as an alternative in the control of bacterial contamination in the alcoholic fermentation process.

Bacterial contamination causes irreparable losses in the performance of alcoholic fermentation. Antibiotics are used to control these microorganisms, but they generate residues and cause microbial resistance. Today the only commercial product used by the mills is hops, but it is very expensive. As an alternative, the objective of this work was to evaluate the feasibility of using extracts from plants grown in the Cerrado for antimicrobial control during an alcoholic fermentation to replace antibiotics. Hydraethanolic extracts of leaves and essential oil of the following species were tested: Schinus terebinthifolius Raddi, Serjania erecta, Serjania marginata, Campomanesia adamantium and Syzygium cumini. Only the extract of Serjania marginata did not show any activity against the bacterium Bacillus sp. Both the essential oils as well as the hydroalcoholic extracts of S. terebinthifolius and C. adamantium and the extract of S. erecta showed antibacterial activity without harming the yeast, with potential to replace the hops.

Intracellular Protective Functions and Therapeutical Potential of Trehalose.

Trehalose is a naturally occurring, non-reducing saccharide widely distributed in nature. Over the years, research on trehalose has revealed that this initially thought simple storage molecule is a multifunctional and multitasking compound protecting cells against various stress factors. This review presents data on the role of trehalose in maintaining cellular homeostasis under stress conditions and in the virulence of bacteria and fungi. Numerous studies have demonstrated that trehalose acts in the cell as an osmoprotectant, chemical chaperone, free radical scavenger, carbon source, virulence factor, and metabolic regulator. The increasingly researched medical and therapeutic applications of trehalose are also discussed.

Synthesis, Electronic, and Antibacterial Properties of 3,7-Di(hetero)aryl-substituted Phenothiazinyl N-Propyl Trimethylammonium Salts.

In this study, a library of 3,7-di(hetero)aryl-substituted 10-(3-trimethylammoniumpropyl)10H-phenothiazine salts is prepared. These title compounds and their precursors are reversible redox systems with tunable potentials. The Hammett correlation gives a very good correlation of the first oxidation potentials with σp parameters. Furthermore, the title compounds and their precursors are blue to green-blue emissive. Screening of the salts reveals for some derivatives a distinct inhibition of several pathogenic bacterial strains (Mycobacterium tuberculosis, Staphylococcus aureus, Escherichia coli, Aconetobacter baumannii, and Klebsiella pneumoniae) in the lower micromolar range.