The purpose of the present study was to purify and characterize the catechol 1,2-dioxygenase (EC 1.13.11.1; catechol-oxygen 1,2-oxidoreductase; C12O) enzyme from the local isolate of Pseudomonas putida. This enzyme catalyzes the initial reaction in the ortho-pathway for phenol degradation in various gram-negative bacteria, including the genus of Pseudomonas. Pseudomonads are commonly used in the biodegradation of xenobiotics due to their versatility in degrading a wide range of chemical compounds. Eighty-nine soil samples were taken from the contaminated soil of the Midland Refineries Company (MRC) of Al-Daura refinery area at Baghdad from April to August 2021. The samples were grown in a mineral salt medium containing 250 mg per L of phenol to test their ability to biodegrade phenol. The pH was adjusted to 8.0 at 30 °C using a shaking incubator for 24-48 h. A number of 62 (69.6%) isolates of the total number were able to degrade phenol efficiently. The findings of the VITEK system and the housekeeping gene 16S rDNA confirmed that out of the positive isolates for phenol degradation, 36 from 62 (58.06%) were identified as Pseudomonas spp. isolates. Those isolates were distributed as P. aeruginosa 30 (83.3%) and P. putida 6 (16.6%). The enzyme production capabilities of the isolates were evaluated, and the highest activity was 2.39 U per mg for the isolate No. 15 which it was identified as P. putida. The previous isolate was selected for enzyme production, purification, and characterization. The enzyme was purified using ion exchange and gel filtration chromatography, with a combined yield of 36.12% and purification fold of 15.42 folds. Using a gel filtration column, the enzyme's molar mass was calculated to be 69 kDa after purification. The purified enzyme was stable at 35 °C and a pH of 6.0.
- MeSH
- bakteriální proteiny metabolismus genetika chemie izolace a purifikace MeSH
- biodegradace * MeSH
- fenol * metabolismus MeSH
- fylogeneze MeSH
- katechol-1,2-dioxygenasa * metabolismus genetika MeSH
- koncentrace vodíkových iontů MeSH
- Pseudomonas putida * enzymologie genetika metabolismus MeSH
- půdní mikrobiologie * MeSH
- RNA ribozomální 16S genetika MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
Flavonoids are associated with positive cardiovascular effects. However, due to their low bioavailability, metabolites are likely responsible for these properties. Recently, one of these metabolites, 4-methylcatechol, was described to be a very potent antiplatelet compound. This study aimed to compare its activity with its 22 close derivatives both of natural or synthetic origin in order to elucidate a potential structure-antiplatelet activity relationship. Blood from human volunteers was induced to aggregate by arachidonic acid (AA), collagen or thrombin, and plasma coagulation was also studied. Potential toxicity was tested on human erythrocytes as well as on a cancer cell line. Our results indicated that 17 out of the 22 compounds were very active at a concentration of 40 μM and, importantly, seven of them had an IC50 on AA-triggered aggregation below 3 μM. The effects of the most active compounds were confirmed on collagen-triggered aggregation too. None of the tested compounds was toxic toward erythrocytes at 50 μM and four compounds partly inhibited proliferation of breast cancer cell line at 100 μM but not at 10 μM. Additionally, none of the compounds had a significant effect on blood coagulation or thrombin-triggered aggregation. This study hence reports four phenol derivatives (4-ethylcatechol, 4-fluorocatechol, 2-methoxy-4-ethylphenol and 3-methylcatechol) suitable for future in vivo testing.
- MeSH
- agregace trombocytů * MeSH
- fenol * MeSH
- fenoly farmakologie MeSH
- inhibitory agregace trombocytů farmakologie MeSH
- lidé MeSH
- trombin farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This study describes the discovery of novel prodrugs bearing tyrosine derivatives instead of the phenol moiety present in FDA-approved tenofovir alafenamide fumarate (TAF). The synthesis was optimized to afford diastereomeric mixtures of novel prodrugs in one pot (yields up to 86%), and the epimers were resolved using a chiral HPLC column into fast-eluting and slow-eluting epimers. In human lymphocytes, the most efficient tyrosine-based prodrug reached a single-digit picomolar EC50 value against HIV-1 and nearly 300-fold higher selectivity index (SI) compared to TAF. In human hepatocytes, the most efficient prodrugs exhibited subnanomolar EC50 values for HBV and up to 26-fold higher SI compared to TAF. Metabolic studies demonstrated markedly higher cellular uptake of the prodrugs and substantially higher levels of released tenofovir inside the cells compared to TAF. These promising results provide a strong foundation for further evaluation of the reported prodrugs and their potential utility in the development of highly potent antivirals.
- MeSH
- amidy chemie MeSH
- antivirové látky chemie farmakologie MeSH
- fenol chemie MeSH
- hepatocyty virologie MeSH
- HIV-1 účinky léků MeSH
- kyseliny fosforečné chemie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- objevování léků * MeSH
- prekurzory léčiv chemie farmakologie MeSH
- stereoizomerie MeSH
- tenofovir chemie farmakologie MeSH
- tyrosin chemie MeSH
- virus hepatitidy B účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The potential of the culturable bacterial community from an Alpine coniferous forest site for the degradation of organic polymers and pollutants at low (5 °C) and moderate (20 °C) temperatures was evaluated. The majority of the 68 strains belonged to the phylum Proteobacteria (77%). Other strains were related to Bacteroidetes (12%), Alphaproteobacteria (4%), Actinobacteria (3%), and Firmicutes (3%). The strains were grouped into 42 different OTUs. The highest bacterial diversity was found within the phylum Bacteroidetes. All strains, except one, could grow at temperatures from 5 to 25 °C. The production of enzyme activities involved in the degradation of organic polymers present in plant litter (carboxymethyl cellulose, microgranular cellulose, xylan, polygalacturonic acid) was almost comparable at 5 °C (68%) and 20 °C (63%). Utilizers of lignin compounds (lignosulfonic acid, lignin alkali) as sole carbon source were found to a higher extent at 20 °C (57%) than at 5 °C (24%), but the relative fractions among positively tested strains utilizing these compounds were almost identical at the two temperatures. Similar results were noted for utilizers of organic pollutants (n-hexadecane, diesel oil, phenol, glyphosate) as sole carbon source. More than two-thirds showed constitutively expressed catechol-1,2-dioxygenase activity both at 5 °C (74%) and 20 °C (66%). Complete phenol (2.5 mmol/L) degradation by strain Paraburkholderia aromaticivorans AR20-38 was demonstrated at 0-30 °C, amounts up to 7.5 mmol/L phenol were fully degraded at 10-30 °C. These results are useful to better understand the effect of changing temperatures on microorganisms involved in litter degradation and nutrient turnover in Alpine forest soils.
- MeSH
- Bacteria klasifikace genetika izolace a purifikace metabolismus MeSH
- bakteriální proteiny metabolismus MeSH
- biodegradace MeSH
- biodiverzita MeSH
- biopolymery metabolismus MeSH
- cévnaté rostliny mikrobiologie MeSH
- fenol metabolismus MeSH
- fylogeneze MeSH
- látky znečišťující životní prostředí metabolismus MeSH
- lesy * MeSH
- lignin metabolismus MeSH
- půdní mikrobiologie MeSH
- RNA ribozomální 16S genetika MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
The new screening method for rapid evaluation of major phenolic compounds in apples has been developed. Suitability of coupling HPLC/UHPLC separation with the diode-array detection and universal charged aerosol detection with respect to the presence of interfering substances was tested. Characteristics of both detection techniques were compared and method linearity, limits of detection and quantitation, and selectivity of them determined. Student t-test based on slopes of calibration plots was applied for the detailed comparison. The diode-array detection provided the best results regarding sensitivity and selectivity of the developed method in terms of evaluation of phenolics profiles. The response of the charged aerosol detector was negatively affected by co-eluting substances during rapid-screening analyses. Coulometric detection was used for advanced characterization of extracts in terms of antioxidant content and strength to obtain more complex information concerning sample composition. This detection also allowed evaluation of unidentified compounds with antioxidant activity. HPLC/UHPLC separation using a combination of diode-array and coulometric detectors thus represented the best approach enabling quick, yet complex characterization of bioactive compounds in apples.
- MeSH
- aerosoly chemie MeSH
- antioxidancia chemie MeSH
- chromatografie metody MeSH
- elektrochemie metody MeSH
- fenol chemie MeSH
- fenoly analýza MeSH
- kalibrace MeSH
- limita detekce MeSH
- Malus metabolismus MeSH
- potravinářská technologie MeSH
- reprodukovatelnost výsledků MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
Cost-effective pretreatment of the highly concentrated and biorefractory coking wastewater to improve biodegradability is of significant importance, while green electrochemical technologies without external chemicals addition are charming but still challenging due to its high energy consumption. In this work, a novel multi-stages flow through peroxi-coagulation (PC) was for the first time developed with graphite felt cathode modified by graphene, showing an excellent performance in removal of 71.5% COD, 72.3% phenol and 59.4% NH3-N and significant biodegradability enhancement with a low energy consumption as 1.2 kWh/m3. Compared with conventional flow PC, this process was more cost-effective due to more intensive .OH production and higher utilization of generated active species. Through UV spectrophotometry and GC-MS analysis, the improvement of biodegradability was attributed to the reduction of both low and high molecular weight compounds content in the coking wastewater. Comparing to the electro-Fenton, electrocoagulation and ozonation process, the proposed PC process was highly cost-effective, providing a promising and new alternative for pretreatment of coking wastewater.
The microbial fuel cells (MFCs) are recognized to be highly effective for the biodegradation of phenol. For isolating the phenol-degrading bacteria, the sample containing 500 mg/L phenol was collected from the MFCs. The strain (WL027) was identified basing on the 16S rRNA gene analysis and phylogenetic analysis as Bacillus cereus. The effects of pH, temperature, concentrations of phenol, heavy metal ions, and salt on the growth of strain as well as the degradation of phenol have been carefully studied. The WL027-strain exhibited favorable tolerance for the metal cations including Cr2+, Co2+, Pb2+, and Cu2+ with the concentration of 0.2 mg/L and NaCl solution with a high concentration of 30 g/L. In 41 h, 86.44% of 500 mg/L phenol has been degraded at the initial pH at 6 and the temperature of 30 °C. The strain was highly active electrogenesis bacteria and the coulombic efficiency reached 64.25%, which showed significant advantage on the efficient energy conversion. Therefore, due to the highly efficient degradation of phenol, WL027-strain could be used in the treatment of phenol-containing wastewater.
- MeSH
- Bacteria klasifikace genetika izolace a purifikace metabolismus MeSH
- biodegradace MeSH
- fenol metabolismus MeSH
- fylogeneze MeSH
- koncentrace vodíkových iontů MeSH
- teplota MeSH
- těžké kovy analýza metabolismus MeSH
- zdroje bioelektrické energie mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
A 32-year-old pregnant woman in the 25th week of pregnancy underwent oral glucose tolerance screening at the diabetologist's. Later that day, she was found dead in her apartment possibly poisoned with Chlumsky disinfectant solution (solutio phenoli camphorata). An autopsy revealed chemical burns in the digestive system. The lungs and the brain showed signs of severe edema. The blood of the woman and fetus was analyzed using gas chromatography with mass spectrometry and revealed phenol, its metabolites (phenyl glucuronide and phenyl sulfate) and camphor. No ethanol was found in the blood samples. Both phenol and camphor are contained in Chlumsky disinfectant solution, which is used for disinfecting surgical equipment in healthcare facilities. Further investigation revealed that the deceased woman had been accidentally administered a disinfectant instead of a glucose solution by the nurse, which resulted in acute intoxication followed by the death of the pregnant woman and the fetus.
- MeSH
- chybná zdravotní péče * MeSH
- dezinficiencia otrava MeSH
- dospělí MeSH
- fenol krev MeSH
- glukózový toleranční test MeSH
- lidé MeSH
- plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
- těhotenství MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
The aim of this study was to design an effective method for the bioremediation of coking wastewaters, specifically for the concurrent elimination of their highly toxic components - cyanide and phenols. Almost full degradation of free cyanide (0.32-20 mM; 8.3-520 mg L(-1)) in the model and the real coking wastewaters was achieved by using a recombinant cyanide hydratase in the first step. The removal of cyanide, a strong inhibitor of tyrosinase, enabled an effective degradation of phenols by this enzyme in the second step. Phenol (16.5 mM, 1,552 mg L(-1)) was completely removed from a real coking wastewater within 20 h and cresols (5.0 mM, 540 mg L(-1)) were removed by 66% under the same conditions. The integration of cyanide hydratase and tyrosinase open up new possibilities for the bioremediation of wastewaters with complex pollution.
- MeSH
- fenol metabolismus MeSH
- fenoly metabolismus MeSH
- koks MeSH
- kyanidy metabolismus MeSH
- odpadní voda * MeSH
- tyrosinasa MeSH
- Publikační typ
- časopisecké články MeSH
Phenol and its derivatives (alkylphenols, halogenated phenols, nitrophenols) are natural or man-made aromatic compounds that are ubiquitous in nature and in human-polluted environments. Many of these substances are toxic and/or suspected of mutagenic, carcinogenic, and teratogenic effects. Bioremediation of the polluted soil and water using various bacteria has proved to be a promising option for the removal of these compounds. In this review, we describe a number of peripheral pathways of aerobic and anaerobic catabolism of various natural and xenobiotic phenolic compounds, which funnel these substances into a smaller number of central catabolic pathways. Finally, the metabolites are used as carbon and energy sources in the citric acid cycle. We provide here the characteristics of the enzymes that convert the phenolic compounds and their catabolites, show their genes, and describe regulatory features. The genes, which encode these enzymes, are organized on chromosomes and plasmids of the natural bacterial degraders in various patterns. The accumulated data on similarities and the differences of the genes, their varied organization, and particularly, an astonishingly broad range of intricate regulatory mechanism may be read as an exciting adventurous book on divergent evolutionary processes and horizontal gene transfer events inscribed in the bacterial genomes. In the end, the use of this wealth of bacterial biodegradation potential and the manipulation of its genetic basis for purposes of bioremediation is exemplified. It is envisioned that the integrated high-throughput techniques and genome-level approaches will enable us to manipulate systems rather than separated genes, which will give birth to systems biotechnology.
