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Frontiers in Public Health 2021Disinfection is a key element in controlling infections. Fogging, also known as fumigation, is one of the most effective chemical disinfection methods. Peracetic acid...
Disinfection is a key element in controlling infections. Fogging, also known as fumigation, is one of the most effective chemical disinfection methods. Peracetic acid (PAA) is a powerful oxidant with bactericidal and fungicidal properties. The aim of this study is to determine the type of bacteria and fungi present in educational institutions and whether disinfection by PAA fumigation in these institutions is also effective and useful, as demonstrated previously in healthcare centers. This study was carried out in five kindergartens and five primary schools in Bialystok, Poland. Three rooms have been selected in each of these educational institutions, and the disinfection was carried out in 30 rooms in total. Fogging with PAA was performed in selected rooms. Before and after disinfection, samples were collected from four surfaces: walls, tables, doors, and chair backs. Most frequently detected microorganisms in schools and kindergartens were ssp. . In addition, ssp. were the most prevalent in kindergartens, whereas was the most prevalent in schools. Comparison of the bacterial flora of schools and kindergartens showed statistically significant differences in the prevalence of bacteria on different surfaces. A significant decrease in the number of colonies after disinfection was observed on all surfaces ( < 0.05). In addition, the calculated effectiveness of disinfection was 99.7% in kindergartens and 99.3% in schools. The results indicate that fogging of PAA is a highly effective method of surface disinfection in kindergartens and schools.
Topics: Acinetobacter; Actinobacteria; Micrococcaceae; Paracoccus; Peracetic Acid; Schools; Staphylococcus
PubMed: 34604154
DOI: 10.3389/fpubh.2021.697917 -
3 Biotech Jul 2021In this study, hydrolytic and oxidative activities of enzymes isolated from halophilic microbes were characterized and applied for biomass utilization. First, lipase...
In this study, hydrolytic and oxidative activities of enzymes isolated from halophilic microbes were characterized and applied for biomass utilization. First, lipase from , and peroxidase and laccase from and were selected and their catalytic activities were determined, respectively. The lipase encoding gene was synthesized after codon-optimization and could be successfully expressed in with the assist of the Tif chaperone protein. The purified enzyme showed 119.13 ± 7.18 and 34.42 ± 5.91 U/mL of lipase and esterase activities, respectively. Moreover, the lipase was applied for hydrolysis of the triglycerides mixture, which resulted in 182.9 ± 11.1 mg/L/h of glycerol productivity. Next, peroxidase and laccase activities of and were determined, and extracellular enzymes of was applied for lignocellulosic biomass degradation, which resulted in 91.9 μg glucose/mg lignocellulose of production yields. Finally, the hydrolytic and oxidative activities of the enzymes from halophilic microbes could be further utilized for biomass treatment and biochemical production.
PubMed: 34295605
DOI: 10.1007/s13205-021-02902-9 -
Molecules (Basel, Switzerland) Jul 2023A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from...
A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from 4-(3-chlorophenyl)-5-(3-fluorophenyl)-2,4-dihydro-3-1,2,4-triazole-3-thione and different piperazine derivatives. The structures of the products were confirmed by H and C NMR and elemental analysis. The activity of piperazine derivatives against bacteria (Gram-positive: , , , , and ; Gram-negative: , , , and ) and yeasts (, , and ) was determined by the minimum inhibitory concentration and minimum bactericidal concentration values. Significant activity was observed against Gram-positive bacteria, mainly staphylococci (-) and bacteria of the genes of and (), as well as selected strains of Gram-negative bacteria, including bacteria of the family (), while all tested compounds showed high fungistatic activity against spp. yeasts, especially , with MICs ranging from 0.49 µg/mL () to 0.98 µg/mL () and 62.5 µg/mL (). In conclusion, the results obtained confirm the multidirectional antimicrobial activity of the newly synthesized piperazine derivatives. Furthermore, in silico studies suggest that the tested compounds are likely to have good oral bioavailability. The results obtained will provide valuable data for further research into this interesting group of compounds. The library of compounds obtained is still the subject of pharmacological research aimed at finding new interesting biologically active compounds.
Topics: Piperazine; Mannich Bases; Bacteria; Gram-Positive Bacteria; Microbial Sensitivity Tests; Gram-Negative Bacteria; Candida; Anti-Infective Agents; Anti-Bacterial Agents
PubMed: 37513434
DOI: 10.3390/molecules28145562 -
PloS One 2022The higher airborne microbial concentration in indoor areas might be responsible for the adverse indoor air quality, which relates well with poor respiratory and general...
The higher airborne microbial concentration in indoor areas might be responsible for the adverse indoor air quality, which relates well with poor respiratory and general health effects in the form of Sick building syndromes. The current study aimed to isolate and characterize the seasonal (winter and spring) levels of culturable bio-aerosols from indoor air, implicating human health by using an epidemiological health survey. Microorganisms were identified by standard macro and microbiological methods, followed by biochemical testing and molecular techniques. Sampling results revealed the bacterial and fungal aerosol concentrations ranging between (300-3650 CFU/m3) and (300-4150 CFU/m3) respectively, in different microenvironments during the winter season (December-February). However, in spring (March-May), bacterial and fungal aerosol concentrations were monitored, ranging between (450-5150 CFU/m3) and (350-5070 CFU/m3) respectively. Interestingly, Aspergillus and Cladosporium were the majorly recorded fungi whereas, Staphylococcus, Streptobacillus, and Micrococcus found predominant bacterial genera among all the sites. Taken together, the elevated levels of bioaerosols are the foremost risk factor that can lead to various respiratory and general health issues in additional analysis, the questionnaire survey indicated the headache (28%) and allergy (20%) were significant indoor health concerns. This type of approach will serve as a foundation for assisting residents in taking preventative measures to avoid exposure to dangerous bioaerosols.
Topics: Air Microbiology; Air Pollution, Indoor; Aspergillus; Bacteria; Cladosporium; Environmental Monitoring; Humans; Seasons; Sick Building Syndrome
PubMed: 35213573
DOI: 10.1371/journal.pone.0264226 -
Frontiers in Microbiology 2018A substantial majority of global population owns cellular phones independently to demographic factors like age, economic status, and educational attainment. In this...
A substantial majority of global population owns cellular phones independently to demographic factors like age, economic status, and educational attainment. In this study, we investigated the diversity of microorganisms associated with cellular phones of 27 individuals using cultivation-based methods. Cellular phones were sampled using cotton swabs and a total of 554 isolates representing different morphotypes were obtained on four growth media. Matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry could generate protein profiles for 527 isolates and species-level identification was obtained for 415 isolates. A dendrogram was constructed based on the protein profiles of the remaining isolates, to group 112 isolates under 39 different proteotypes. The representative strains of each group were selected for 16S rRNA gene and ITS region sequencing based identification. , , , and were the most frequently encountered bacteria, and , , , and were in case of fungi. At species-level the prevalence of , , , , , and was observed, most of these species are commensal microorganisms of human skin. UPGMA dendrogram and PCoA biplot generated based on the microbial communities associated with all cellular phones exhibited build-up of specific communities on cellular phones and the prevalence of objectionable microorganisms in some of the cellular phones can be attributed to the poor hygiene and sanitary practices. The study also revealed the impact of MALDI-TOF MS spectral quality on the identification results. Overall MALDI-TOF appears a powerful tool for routine microbial identification and de-replication of microorganisms. Quality filtering of MALDI-TOF MS spectrum, development of better sample processing methods and enriching the spectral database will improve the role of MALDI-TOF MS in microbial identifications.
PubMed: 29930546
DOI: 10.3389/fmicb.2018.01229 -
Scientific Reports Oct 2021In recent years' synthesis of metal nanoparticle using plants has been extensively studied and recognized as a non-toxic and efficient method applicable in biomedical...
In recent years' synthesis of metal nanoparticle using plants has been extensively studied and recognized as a non-toxic and efficient method applicable in biomedical field. The aim of this study is to investigate the role of different parts of medical plant Carduus crispus on synthesizing silver nanoparticles and characterize the produced nanoparticle. Our study showed that silver nanoparticles (AgNP) synthesized via whole plant extract exhibited a blue shift in absorption spectra with increased optical density, which correlates to a high yield and small size. Also, the results of zeta potential, X-ray diffraction, photon cross-correlation spectroscopy analysis showed the surface charge of - 54.29 ± 4.96 mV (AgNP-S), - 42.64 ± 3.762 mV (AgNP-F), - 46.02 ± 4.17 mV (AgNP-W), the crystallite size of 36 nm (AgNP-S), 13 nm (AgNP-F), 14 nm (AgNP-W) with face-centered cubic structure and average grain sizes of 145.1 nm, 22.5 nm and 99.6 nm. Another important characteristic, such as elemental composition and constituent capping agent has been determined by energy-dispersive X-ray spectroscopy and Fourier transform infrared. The silver nanoparticles were composed of ~ 80% Ag, ~ 15% K, and ~ 7.5% Ca (or ~ 2.8% P) elements. Moreover, the results of the FTIR measurement suggested that the distinct functional groups present in both AgNP-S and AgNP-F were found in AgNP-W. The atomic force microscopy analysis revealed that AgNP-S, AgNP-F and AgNP-W had sizes of 131 nm, 33 nm and 70 nm respectively. In addition, the biosynthesized silver nanoparticles were evaluated for their cytotoxicity and antibacterial activity. At 17 µg/ml concentration, AgNP-S, AgNP-F and AgNP-W showed very low toxicity on HepG2 cell line but also high antibacterial activity. The silver nanoparticles showed antibacterial activity on both gram-negative bacterium Escherichia coli (5.5 ± 0.2 mm to 6.5 ± 0.3 mm) and gram-positive bacterium Micrococcus luteus (7 ± 0.4 mm to 7.7 ± 0.5 mm). Our study is meaningful as a first observation indicating the possibility of using special plant organs to control the characteristics of nanoparticles.
Topics: Anti-Bacterial Agents; Carduus; Escherichia coli; Hep G2 Cells; Humans; Metal Nanoparticles; Micrococcus luteus; Silver
PubMed: 34702916
DOI: 10.1038/s41598-021-00520-2 -
Microbes and Environments 2022Phosphorus (P) is an essential macronutrient for plant growth and is mainly present in agricultural soil in unavailable forms. Phosphate-solubilizing microorganisms...
Phosphorus (P) is an essential macronutrient for plant growth and is mainly present in agricultural soil in unavailable forms. Phosphate-solubilizing microorganisms (PSMs) increase soil P availability. The objective of the present study was to assess the population and type of PSMs and their relationships with soil characteristics in the agricultural soil of Manokwari. Twenty-one composite soil samples (0-20 cm) were collected at the rhizospheres of plants in the Prafi and Masni Districts. A dilution technique and plate count method on Pikovskayas agar medium were used to examine the PSM population, phosphate-solubilizing index (PSI), and various soil properties. The results obtained showed that the total population of phosphate-solubilizing bacteria ranged between 25×10 and 550×10 CFU g of soil, while that of phosphate-solubilizing fungi was between 2.0×10 and 5.0×10 CFU g of soil at all locations. The PSI of the isolates ranged between 1.1 to 3.6 mm, with the most efficient and highest PSI being obtained for Bacillus sp. (strain 8) and the lowest for Pseudomonas sp. (strain 15). Six isolates found at all locations were identified at the genus level: Chromobacterium sp., Pseudomonas sp., Bacillus sp., Micrococcus sp., Caulobacter sp., and Aspergillus sp. A correlation was observed between the number of PSMs and the level of soil P availability and moisture content, indicating an increase in soil P availability with a greater abundance of PSMs in soil.
Topics: Agriculture; Demography; Phosphates; Soil; Soil Microbiology
PubMed: 35342122
DOI: 10.1264/jsme2.ME21041 -
Occupational Medicine (Oxford, England) Sep 2018Dental care professionals are exposed to aerosols from the oral cavity of patients containing several pathogenic microorganisms. Bioaerosols generated during dental...
BACKGROUND
Dental care professionals are exposed to aerosols from the oral cavity of patients containing several pathogenic microorganisms. Bioaerosols generated during dental treatment are a potential hazard to dental staff, and there have been growing concerns about their role in transmission of various airborne infections and about reducing the risk of contamination.
AIMS
To investigate qualitatively and quantitatively the bacterial and fungal aerosols before and during clinical sessions in two dental offices compared with controls.
METHODS
An extra-oral evacuator system was used to measure bacterial and fungal aerosols. Macroscopic and microscopic analysis of bacterial species and fungal strains was performed and strains of bacteria and fungi were identified based on their metabolic properties using biochemical tests.
RESULTS
Thirty-three bioaerosol samples were obtained. Quantitative and qualitative evaluation showed that during treatment, there is a significant increase in airborne concentration of bacteria and fungi. The microflora included mainly gram-positive organisms (Staphylococcus epidermidis and Micrococcus spp.), gram-positive rod-shaped bacteria and those creating endospores as well as non-porous bacteria and mould fungi (Cladosporium and Penicillium).
CONCLUSIONS
Exposure to the microorganisms identified is not a significant occupational hazard for dental care professionals; however, evidence-based prevention measures are recommended.
Topics: Aerosols; Cladosporium; Dental Assistants; Dentists; Gastrointestinal Microbiome; Humans; Occupational Exposure; Penicillium; Staphylococcus epidermidis
PubMed: 29931138
DOI: 10.1093/occmed/kqy095 -
Biology Aug 2022Bacterial pigments (e.g., melanin and carotenoids) are considered to be among the most important secondary metabolites due to their various pharmacological activities...
Bacterial pigments (e.g., melanin and carotenoids) are considered to be among the most important secondary metabolites due to their various pharmacological activities against cancer and microbial resistance. Different pigmented bacterial strains were isolated from soil samples from El Mahmoudiyah governance and screened for their antimicrobial activity. The most promising pigment producer was identified as MW407006; furthermore, the produced pigment was identified as echinenone (β-carotene pigment). The pigment production was optimized through a central composite statistical design to maximize the biomass production, pigment concentration, and the antimicrobial activity. It was revealed that the most significant fermentation parameters were the glucose (as a carbon source) and asparagine (as a nitrogen source) concentrations. Nano-echinenone was synthesized using the ball milling technique, characterized, and finally assessed for potential antimicrobial, antioxidant, and antitumor activities. The data revealed that the synthesized nano-echinenone had higher antimicrobial activity than the crude pigment. The cytotoxic potency of echinenone and nano-echinenone was investigated in different cell lines (normal and cancer cells). The inhibition of cell proliferation and induction of cell death was observed in Caco-2 and Hep-G2 cells. The data proved that nano-echinenone is a suitable candidate for use as a safe antimicrobial and anti-hepatocellular-carcinoma agent.
PubMed: 36009797
DOI: 10.3390/biology11081171 -
Ozone disinfection efficiency against airborne microorganisms in hospital environment: a case study.Arhiv Za Higijenu Rada I Toksikologiju Dec 2022Even though ozone has shown its potential for air disinfection in hospital environment, its more frequent use has earned attention only with the COVID-19 pandemic due to...
Even though ozone has shown its potential for air disinfection in hospital environment, its more frequent use has earned attention only with the COVID-19 pandemic due to its proven antimicrobial effect and low cost of production. The aim of this study was to determine its antimicrobial efficiency against the most common bacterial species in a real-life setting, that is, in the air of one postoperative room of the General Hospital Dr Ivo Pedišić (Sisak, Croatia). Air was sampled for aiborne bacteria before and after treatment with the ozone concentration of 15.71 mg/m for one hour. The most dominant Gram-positive bacteria of the genera , and were reduced by 33 %, 58 %, and 61 %, respectively. The genus proved to be the most resistant. Considering our findings, we recommend longer air treatment with higher ozone concentrations in combination with mechanical cleaning and frequent ventilation.
Topics: Humans; Ozone; Disinfection; Pandemics; Air Microbiology; COVID-19; Bacteria; Hospitals
PubMed: 36607720
DOI: 10.2478/aiht-2022-73-3651