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Scientific Reports May 2024In the present study, ten (10) selected bacteria isolated from chasmophytic wild Chenopodium were evaluated for alleviation of drought stress in chickpea. All the...
In the present study, ten (10) selected bacteria isolated from chasmophytic wild Chenopodium were evaluated for alleviation of drought stress in chickpea. All the bacterial cultures were potential P, K and Zn solubilizer. About 50% of the bacteria could produce Indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase. The bacteria showed wide range of tolerance towards pH, salinity, temperature and osmotic stress. Bacillus paralicheniformis L38, Pseudomonas sp. LN75, Enterobacter hormachei subsp. xiangfengensis LJ89, B. paramycoides L17 and Micrococcus luteus LA9 significantly improved growth and nutrient (N, P, K, Fe and Zn) content in chickpea under water stress during a green house experiment conducted following a completely randomized design (CRD). Application of Microbacterium imperiale LJ10, B. stercoris LN74, Pseudomonas sp. LN75, B. paralicheniformis L38 and E. hormachei subsp. xiangfengensis LJ89 reduced the antioxidant enzymes under water stress. During field experiments conducted following randomized block design (RBD), all the bacterial inoculations improved chickpea yield under water stress. Highest yield (1363 kg ha) was obtained in plants inoculated with Pseudomonas sp. LN75. Pseudomonas sp. LN75, B. paralicheniformis L38 and E. hormachei subsp. xiangfengensis LJ89 have potential as microbial stimulants to alleviate the water stress in chickpea. To the best of our knowledge this is the first report of using chasmophyte associated bacteria for alleviation of water stress in a crop plant.
Topics: Cicer; Droughts; Stress, Physiological; Bacteria; Indoleacetic Acids; Nutrients; Carbon-Carbon Lyases; Enterobacter; Pseudomonas; Antioxidants
PubMed: 38806526
DOI: 10.1038/s41598-024-58695-3 -
Microorganisms May 2024Spontaneous Bacterial Peritonitis (SBP) is a serious complication and a common cause of death in patients with liver cirrhosis. Between January 2017 and March 2024, a...
Spontaneous Bacterial Peritonitis (SBP) is a serious complication and a common cause of death in patients with liver cirrhosis. Between January 2017 and March 2024, a retrospective study was conducted involving 302 patients (>18 years old) with ascites treated at a tertiary referral center in south-eastern Poland. Microbiological analysis of the ascitic fluids was performed in all patients. The presence of microorganisms was found in samples from 17 patients, and 21 pathogens were isolated, including 15 Gram-positive bacteria and 6 Gram-negative bacteria. , MRCNS (methicillin-resistant coagulase-negative staphylococci, resistant to all beta-lactam antibiotics: penicillins, penicillins with beta-lactamase inhibitor, cephalosporins and carbapenems) was the main pathogen detected (19.05%, 4/21), followed by (9.52%, 2/21), (9.52%, 2/21), , MRCNS (4.76%, 1/21), (9.52%, 2/21), (9.52%, 2/21), (4.76%, 1/21) and spp. (4.76%, 1/21). The following Gram-negative bacteria were also found in the specimens examined: , ESBL (extended-spectrum β-lactamase producing ) (4.76%, 1/21), (4.76%, 1/21), (4.76%, 1/21), (9.52%, 2/21) and (4.76%, 1/21). Gram-positive bacteria caused nosocomial infections in nine patients with SBP, Gram-negative bacteria caused nosocomial infections in two patients. In six patients with SBP, community-acquired infections caused by Gram-negative bacteria were found in three cases, Gram-positive bacteria in two cases, and in one case, community-acquired infection was caused by mixed Gram-positive and Gram-negative. Bacteria isolated from patients with hospital-acquired SBP showed higher drug resistance than those found in patients with non-hospital SBP. Bacterial infections in cirrhotic patients with complications may be responsible for their deteriorating health. Prompt intervention is critical to reducing mortality.
PubMed: 38792837
DOI: 10.3390/microorganisms12051008 -
Molecules (Basel, Switzerland) May 2024Prediction of the antibacterial activity of new chemical compounds is an important task, due to the growing problem of bacterial drug resistance. Generalized linear...
Prediction of the antibacterial activity of new chemical compounds is an important task, due to the growing problem of bacterial drug resistance. Generalized linear models (GLMs) were created using 85 amidrazone derivatives based on the results of antimicrobial activity tests, determined as the minimum inhibitory concentration (MIC) against Gram-positive bacteria: , , , , and . For the analysis of compounds characterized by experimentally measured MIC values, we included physicochemical properties (e.g., molecular weight, number of hydrogen donors and acceptors, topological polar surface area, compound percentages of carbon, nitrogen, and oxygen, melting points, and lipophilicity) as potential predictors. The presence of R1 and R2 substituents, as well as interactions between melting temperature and R1 or R2 substituents, were also considered. The set of potential predictors also included possible biological effects (e.g., antibacterial, antituberculotic) of tested compounds calculated with the PASS (Prediction of Activity Spectra for Substances) program. Using GLMs with least absolute shrinkage and selection (LASSO), least-angle regression, and stepwise selection, statistically significant models with the optimal value of the adjusted determination coefficient and of seven fit criteria were chosen, e.g., Akaike's information criterion. The most often selected variables were as follows: molecular weight, PASS_antieczematic, PASS_anti-inflam, squared melting temperature, PASS_antitumor, and experimental lipophilicity. Additionally, relevant to the bacterial strain, the interactions between melting temperature and R1 or R2 substituents were selected, indicating that the relationship between MIC and melting temperature depends on the type of R1 or R2 substituent.
Topics: Anti-Bacterial Agents; Microbial Sensitivity Tests; Gram-Positive Bacteria; Structure-Activity Relationship; Molecular Structure
PubMed: 38792231
DOI: 10.3390/molecules29102369 -
Data in Brief Jun 2024A Gram-positive bacterium designated as strain ORF15-23 was isolated from a soil sample collected from rainfed organic paddy fields in Roi Et province, Thailand. This...
A Gram-positive bacterium designated as strain ORF15-23 was isolated from a soil sample collected from rainfed organic paddy fields in Roi Et province, Thailand. This strain is previously reported to produce indole-3-acetic acid and 2-acetyl-1-pyrroline (2AP) compound, solubilize potassium feldspar and promote growth of rice seedlings. The genome sequencing was carried out using Illumina MiSeq platform. The draft genome of strain ORF15-23 was 2,562,005 bp in length with 1677 protein coding sequences and an average G + C content of 72.97 mol.%. Phylogenomic tree supports the assignment of strain ORF15-23 as member of the genus . A comparison of average nucleotide identity (ANIb) values revealed that strain ORF15-23 shared 96.95 % identity with the genome of DSM 21948. The draft genome sequence of ORF15-23 has been deposited in the DDBJ/EMBL/GenBank databases under the accession number JAZDRZ000000000. This genome sequence data provides insightful information for the taxonomic characterization and further biotechnological exploitation of ORF15-23.
PubMed: 38774239
DOI: 10.1016/j.dib.2024.110466 -
Cureus Apr 2024Preserving sterility and safety in hospital operation theaters (OTs) is vital. We have implemented a comprehensive microbiological surveillance program for OTs,...
INTRODUCTION
Preserving sterility and safety in hospital operation theaters (OTs) is vital. We have implemented a comprehensive microbiological surveillance program for OTs, encompassing both commencement and ongoing monitoring. This study assesses the prevalence of microorganisms, identifies their types, and detects contamination on surfaces and in the air.
METHODS
Commencement and monitoring samples were collected from October 2021 to July 2023, from nine OTs. OTs were cleaned with soap and water, disinfected, and fogged with quaternary ammonium compounds. After sealing the OTs overnight, samples were collected aseptically. Air was sampled using the settle plate method, and surfaces were swabbed. Six surfaces, namely, the floor, wall, table, light, anesthesia workstation, and door handle, were swabbed. Samples were transported immediately to the institution's microbiology laboratory.
RESULTS
During OT commencement, 247 swabs from nine OTs yielded 19 (7.29%) positives for bacterial growth. These microorganisms were primarily non-pathogenic, including aerobic spore-forming bacilli and Micrococcus, with an average bioload of 9.5 colony-forming units (CFU)/m of air. During OT monitoring, swab positivity was 10.79% (23/213). The General Surgery OT and Obstetrics and Gynecology OT showed the highest bacterial growth (5/23). Surface sampling revealed prevalent methicillin-resistant coagulase-negative staphylococci (MRCoNS) (9/23), followed by methicillin-sensitive (MSSA) (4/23) and methicillin-sensitive coagulase-negative staphylococci (MSCoNS) and aerobic spore-forming bacilli (ASB) (3/10). The General Surgery, Obstetrics and Gynecology, and ENT OTs displayed elevated air bioloads of 53, 49, and 47 CFU/m, respectively.
CONCLUSION
In newly constructed non-operational OTs, non-pathogenic organisms prevailed. However, as the OTs became functional, pathogenic organisms became more prevalent. Sampling emphasized contamination in areas with high patient loads, such as General Surgery, Obstetrics and Gynecology, and ENT OTs. Notably, OT tables and OT walls exhibited higher pathogenic microorganism presence. By combining both initial commencement and ongoing monitoring, the institution has effectively managed the microbial environment within its OTs.
PubMed: 38774178
DOI: 10.7759/cureus.58690 -
PeerJ 2024Nanotechnology and nanoparticles have gained massive attention in the scientific community in recent years due to their valuable properties. Among various AgNPs...
Nanotechnology and nanoparticles have gained massive attention in the scientific community in recent years due to their valuable properties. Among various AgNPs synthesis methods, microbial approaches offer distinct advantages in terms of cost-effectiveness, biocompatibility, and eco-friendliness. In the present research work, investigators have synthesized three different types of silver nanoparticles (AgNPs), namely AgNPs-K, AgNPs-M, and AgNPs-E, by using (MBC34), (MBC23), and (MBX6), respectively. The morphological, chemical, and elemental features of the synthesized AgNPs were analyzed by using UV-Vis spectroscopy (UV-Vis), Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and energy-dispersive spectroscopy (EDX). UV-Vis absorbance peaks were obtained at 475, 428, and 503 nm for AgNPs-K, AgNPs-M, and AgNPs-E, respectively. The XRD analysis confirmed the crystalline nature of the synthesized AgNPs, having peaks at 26.2°, 32.1°, and 47.2°. At the same time, the FTIR showed bands at 599, 963, 1,693, 2,299, 2,891, and 3,780 cm for all the types of AgNPs indicating the presence of bacterial biomolecules with the developed AgNPs. The size and morphology of the AgNPs varied from 10 nm to several microns and exhibited spherical to porous sheets-like structures. The percentage of Ag varied from 37.8% (wt.%) to 61.6%, ., highest in AgNPs-K and lowest in AgNPs-M. Furthermore, the synthesized AgNPs exhibited potential for environmental remediation, with AgNPs-M exhibiting the highest removal efficiency (19.24% at 120 min) for methyl orange dye in simulated wastewater. Further, all three types of AgNPs were evaluated for the removal of methyl orange dye from the simulated wastewater, where the highest dye removal percentage was 19.24% at 120 min by AgNPs-M. Antibacterial potential of the synthesized AgNPs assessment against both Gram-positive (GPB) (MBC23), (MBC24), and Gram-negative bacteria (MBP13) revealed promising results, with AgNPs-M, exhibiting the largest zone of inhibition (12 mm) against GPB . Such investigation exhibits the potential of the bacteria for the synthesis of AgNPs with diverse morphology and potential applications in environmental remediation and antibacterial therapy-based synthesis of AgNPs.
Topics: Silver; Metal Nanoparticles; Azo Compounds; Micrococcus luteus; Spectroscopy, Fourier Transform Infrared; Anti-Infective Agents; Klebsiella pneumoniae; Microbial Sensitivity Tests; Anti-Bacterial Agents; Enterobacter aerogenes; X-Ray Diffraction; Water Pollutants, Chemical; Coloring Agents
PubMed: 38770094
DOI: 10.7717/peerj.17328 -
Chemosphere May 2024The aerodynamic sizes of bioaerosols may significantly affect their behaviors, respiratory deposition and biodiversity. The respirable bacterial size, biodiversity, and...
The aerodynamic sizes of bioaerosols may significantly affect their behaviors, respiratory deposition and biodiversity. The respirable bacterial size, biodiversity, and human-associated bacteria (HAB) related bioaerosols were evaluated at three kindergartens in Taiwan. Kindergartens A, B, and C were in urban, semi-urban, and rural areas, respectively. A six-stage viable Andersen cascade impactor was used to collect bioaerosols and to determine their size distributions. The geometric mean diameter (GMD), geometric standard deviation (GSD), heat maps, and uniformity were used to evaluate the association of bacteria characteristics. A BD Phoenix-100 automated interpretation system was used to identify the airborne bacteria species. The results revealed that 1425 colonies of the sampled airborne bacteria contained 63 species in 29 genera, and overall, 63.0% were HABs. The most abundant phylum was Actinobacteria (56.6 ± 22.2%) and Firmicutes (31.6 ± 22.3%), and from the taxonomic analysis, both airborne Micrococcus and the Staphylococcus aureus are the dominant genus. All the bacteria aerodynamic particle size distributions were polydisperse distributions. The heat map and uniformity analysis had revealed most of the sampled bioaerosols distributed between 1.1-3.3 μm, and most of the polydisperse airborne Streptococcus spp. had a size in the respirable range, due to urbanization, they have potentially contributed to respiratory risk in the kindergartens. The Shannon diversity index (H) and inverse Simpson diversity index (D) of the bioaerosols in urban kindergarten were negatively correlated with GMD and GSD. The Pearson correlations revealed that the kindergarten in the rural area, with a higher temperature, a lower relative humidity, and a lower CO concentration than the others, tended to have the largest H and D values (P < 0.05). Multiple and stepwise regression revealed that bioaerosol aerodynamic size was statistically significantly correlated with H (P = 0.001) and D values (P = 0.002). This study sheds light on the characteristics of bioaerosols and their associations with microbiome.
PubMed: 38759806
DOI: 10.1016/j.chemosphere.2024.142333 -
Chemosphere May 2024This work comprehensively demonstrates the ability of heterotrophic bacteria, isolated from a chloraminated system, to decay chloramine. This study non-selectively...
This work comprehensively demonstrates the ability of heterotrophic bacteria, isolated from a chloraminated system, to decay chloramine. This study non-selectively isolated 62 cultures of heterotrophic bacteria from a water sample (0.002 mg-N/L nitrite and 1.42 mg/L total chlorine) collected from a laboratory-scale reactor system; most of the isolates (93.3%) were Mycobacterium sp. Three species of Mycobacterium and one species of Micrococcus were inoculated to a basal inorganic medium with initial concentrations of acetate (from 0 to 24 mg-C/L) and 1.5 mg/L chloramine. Bacterial growth coincided with declines in the concentrations of chloramine, acetate, and ammonium. Detailed experiments with one of the Mycobacterium sp. isolates suggest that the common mechanism of chloramine loss is auto-decomposition likely mediated by chloramine-decaying proteins. The ability of the isolates to grow and decay chloramine underscores the important role of heterotrophic bacteria in the stability of chloramine in water-distribution systems. Existing strategies based on controlling nitrification should be augmented to include minimizing heterotrophic bacteria.
PubMed: 38754485
DOI: 10.1016/j.chemosphere.2024.142341 -
Frontiers in Microbiology 2024The concentration of antimicrobial agents in environments like water and food has increased rapidly, which led to a rapid increase in antimicrobial resistance levels in...
Practice of standardization of CLSI M45 A3 antimicrobial susceptibility testing of Infrequently Isolated or Fastidious Bacteria strains isolated from blood specimens in Guangdong Province 2017-2021.
The concentration of antimicrobial agents in environments like water and food has increased rapidly, which led to a rapid increase in antimicrobial resistance levels in the environment. Monitoring of bacterial resistance levels is considered as a necessary means to control the bacterial resistance. Reference standards are critical for antimicrobial susceptibility testing. CLSI M45 A3 standard defines pathogenic microorganisms that cause infections less frequently than those covered by CLSI M02, M07, and M100 as Infrequently Isolated or Fastidious Bacteria and specifies antimicrobial susceptibility testing methods. Our study investigated the epidemiology and antimicrobial susceptibility testing data of Infrequently Isolated or Fastidious Bacteria strains isolated from blood specimens in 70 hospitals in Guangdong Province between 2017 and 2021. We defined testing methods other than those specified in CLSI M45 A3 as "Non-Standardized." The proportion of standardized antimicrobial susceptibility testing for penicillin increased significantly ( spp. 17.4% vs. 50.0% < 0.05; spp. 50.0% vs. 77.8% < 0.05; spp. and spp. 21.4% vs. 90.9% < 0.001), while for cefotaxime ( spp. 0.0% vs. 45.2% < 0.05; spp. and spp. 0.0% vs. 14.3% = 0.515) and vancomycin increased finitely. Non-standardized methods were used for all other antimicrobials. Due to limitations in the economic and medical environment, some clinical laboratories are unable to fully comply with CLSI M45 A3 standard. We recommend that CLSI should add breakpoints for disk diffusion method to improve the standardization of antimicrobial susceptibility testing.
PubMed: 38741731
DOI: 10.3389/fmicb.2024.1335169 -
Scientific Reports May 2024The storage process has a significant impact on tea quality. Few is known about effect of storage on quality of oolong tea. This study aimed to assess the effect of...
The storage process has a significant impact on tea quality. Few is known about effect of storage on quality of oolong tea. This study aimed to assess the effect of different storage times on the key chemical components of oolong tea by measuring changes in catechin, free amino acid, and alkaloid content. Variation in the main substances was determined by principal component analysis and heat map analysis. The results revealed notable effects of the storage process on the levels of theanine, epigallocatechin gallate (EGCG), and glutamine. These findings suggest that these compounds could serve as indicators for monitoring changes in oolong tea quality during storage. Additionally, the study observed an increase in the antibacterial ability of tea over time. Correlation analysis indicated that the antibacterial ability against Micrococcus tetragenus and Escherichia coli was influenced by metabolites such as aspartic acid, threonine, serine, gamma-aminobutyric acid, ornithine, alanine, arginine, and EGCG. Overall, this study presents an approach for identifying key metabolites to monitor tea quality effectively with relatively limited data.
Topics: Catechin; Tea; Amino Acids; Anti-Bacterial Agents; Alkaloids; Food Storage; Escherichia coli; Camellia sinensis
PubMed: 38710752
DOI: 10.1038/s41598-024-60951-5