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An efficient urease-catalyzed approach for the synthesis of highly substituted 6-amino-4 H -pyran-3-carbonitriles based on the formation of three bonds in one step is developed. This unprecedented three-component reaction between one molecule of an aromatic aldehyde and two molecules of an aroylacetonitrile proceeds by employing commercially available urease from jack bean (Canavalia ensiformis) as the catalyst in water at 65 °C to deliver the desired 4 H -pyrans in yields of up to 92%. The transformation is proposed to occur via a domino Knoevenagel condensation/1,4-addition/ O -cyclization/tautomerization sequence, providing a practical and sustainable approach to 6-amino-4 H -pyran-3-carbonitriles from commercially available substrates. Full and unambiguous structural elucidation of all the products is achieved by means of NMR spectroscopy and X-ray crystal structure analysis. [ABSTRACT FROM AUTHOR]

Urease enzyme activity can be related to various issues, both in biological systems and in industrial processes. A significant breakthrough in addressing the challenge to maintain enzymatic activity involves the development of enzyme-polymer based bioconjugates. This entails the utilization of dual responsive polymer matrix involving pH-responsive polymer (2-acrylamido-2-methylpropane sulfonic acid (AMPS)), neutral polymer (N, N-dimethylacrylamide (DMA)), temperature-responsive polymer (N-isopropylacrylamide (NIPAM)), and urease derivative (UD) collectively known as [PAMPS-co-PDMA-co-PUD]-b-PNIPAM (ADUN) centered on the RAFT-Grafting through polymerization process. Kinetic assessments, including a comparative study between the free enzyme and urease linked in ADUN, were conducted using berthelot reagents at different pH and temperature levels. The Lineweaver–Burk plot was used to ascertain the Michaelis–Menten kinetic constant (Km) values, which unveiled strikingly similar Km values for the free enzyme and ADUN. This indicates that urease remains active for over a month when stored at room temperature and up to around 70 °C in the case of ADUN, while it becomes dormant in the case of free urease. The microenvironment of the bioconjugates remains intact for urease in acidic pH conditions and at temperatures ranging from mild to high, when the concentration exceeds the critical micelle concentration (CMC). In general, this approach highlights the prolonged durability and commercial adaptability of ADUN for wider uses. [ABSTRACT FROM AUTHOR]

This study investigated the impact of precursor supplementation and incubation time on the quality of palm stem pith silage (nutrient content, in vitro digestibility, and rumen fermentability). A factorial complete randomised design was applied, and the first factor included precursor supplements (D1 - empty bunch ash filtrate, D2 - chicken faeces + urea, D3 - effective microorganism + molasses + urea), while the second factor was incubation periods (B1 - 7 days, B2 - 14 days, B3 - 21 days). Each treatment was replicated 3 times, resulting in 27 experimental units. The results revealed significant main effects of precursor supplementation, incubation time and their interaction on various silage parameters. In particular, a clear interaction (P < 0.01) was observed between precursor supplementation and duration of incubation, indicating significant synergistic effects on nutrient content (dry matter, organic matter, crude protein, crude fibre, extract ether and nitrogen-free extract), digestibility (organic matter and dry matter) and rumen fermentability (NH3 concentration). Specifically, the combination of effective microorganism + molasses + urea supplementation, with a 14-day incubation period, emerged as the most effective strategy for enhancing silage quality. These findings highlight the crucial role of considering treatment interaction factors in optimising silage production processes. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the aqueous methanolic extract of the aerial parts of Dioscorea preussii, led to the isolation of a new chalcone preussiate (1) along with 10 other compounds including xanthomicrol (2), cholestan-3-one (3), arjunolic acid (4), tormentic acid (5), ursolic acid (6), betulin (7), lupeol (8), p-hydroxybenzoic acid (9), isovanillin (10) and vanillic acid (11), being reported for the first time from this plant. Their structures were established by spectroscopic techniques including 2D NMR spectroscopy. All the isolates were subjected to the biological screening but only showed antioxidant and urease inhibitory properties. The compounds 1,8 and 11 displayed the most potent urease inhibitory properties with IC50 values, 22.4, 33.3 and 35.7 µM, respectively, while 3 was moderately active. The compound 11 showed potent antioxidant activity among all the tested isolates with an IC50 value of 45.3 µM. [ABSTRACT FROM AUTHOR]

Chronic Kidney Disease (CKD) is a disorder that affects over 10% of the global population, and that would benefit from innovative methodologies that would provide early detection. Since it has been reported that there are high levels of urease in CKD patients' saliva, this sample is a promising non-invasive alternative to blood for CKD detection and monitoring. This work introduces a novel 3D µPAD for quantifying urease activity in saliva in a range of 0.041–0.750 U/mL, with limits of detection and quantification of 0.012 and 0.041 U/mL, respectively. The device uses the urease in the sample to convert urea into ammonia, causing a colorimetric change in the bromothymol blue. The accuracy of the developed device was evaluated by comparing the measurements of several saliva samples (#13) obtained with the μPAD and with a commercially available kit. Stability studies were also performed to assess its functionality as a point-of-care methodology, and the device was stable for 4 months when stored in a vacuum. After the sample placement, it could be scanned within 40 min without providing significantly different results. The developed device quantifies urease activity in saliva within 30 min, providing a simple, portable, lab-free alternative to existing methodologies. [ABSTRACT FROM AUTHOR]

Abstract\nHighlightsThe flowing-water remediation of contaminated soil was investigated. Urease combined with biochar (UCB) technology was used to handle the Pb2+-contaminated sand column. The results showed that with the continuous increase of pore volume, the concentration of Pb2+ in the leachate undergoes three stages: slow growth, rapid growth, and steady state. With increasing seepage velocity, the concentration of Pb2+ in leachate increased slightly. The residual amount of each section of the sand column gradually decreased with increasing migration distance. The comparative results indicated that the UCB technology had a good solidification effect on Pb2+. This was due to urease-induced CaCO3 precipitation, cementation, and adsorption of Pb2+. Biochar provided more nucleation sites for urease, and some Pb2+ was adsorbed on its surface or diffused into the pores of biochar, or ions exchanged with functional groups on the surface of biochar, which effectively stabilized the free Pb2+.Flowing-water remediation experiments of urease combined with biochar on Pb2+ was completed.Remediation steps of Pb2+-contaminated soil using UCB were proposed.Solidification principle of UCB was revealed by direct sampling detection.Flowing-water remediation experiments of urease combined with biochar on Pb2+ was completed.Remediation steps of Pb2+-contaminated soil using UCB were proposed.Solidification principle of UCB was revealed by direct sampling detection. [ABSTRACT FROM AUTHOR]

A series of bis-coumarin-perimidine hybrids were designed and synthesized, and their structures were characterized by FT-IR, 1H NMR, 13C NMR, and elemental analyses spectral data. All newly synthesized compounds were screened for their urease activity. All synthesized compounds were found to be effective in urease enzyme inhibition. With IC50 values ranging from 0.022 ± 0.50 to 0.098 ± 0.10 µM, the compounds exhibit more active inhibition than the standard thiourea (IC50 = 0.206 ± 0.25 µM). The compound N′,N′′-(2,2′-(2,2′-(2-oxo-1H-perimidine-1,3(2H)-diyl)bis(acetyl))bis(6-bromo-2-oxo-2H-chromene-3-carbohydrazide) has the best urease inhibition with IC50 = 0.022 ± 0.50 µM. [ABSTRACT FROM AUTHOR]

Background: Triphala, is a composite of three individual botanical drugs: Terminalia chebula , Terminalia bellirica , and Emblica officinalis. It exhibits properties such as heatclearing, anti-inflammatory, anti-fatigue, antioxidant, and antibacterial effects,making it extensively utilized in India and Tibet. It has been found to exhibitinhibitory effects on Helicobacter pylori (H. pylori); however, further comprehensive research is still needed to elucidate its specific antibacterial mechanism. The present study investigates the in vitro antibacterial activity and antibacterial mechanism of Triphala against H. pylori. Methods: Ours research investigates the in vitro inhibitory activity of Triphala on multiple standard and clinical strains using microdilution broth method, time-kill curve, time-bactericidal curve and scanning electron microscopy (SEM). Furthermore, the antibacterial mechanism of Triphala is further explored through experiments on urease activity, biofilm formation, anti-adhesion properties, virulence actor assays using RT-qPCR and Western Blotting techniques. Results: The research findings indicate that Triphala exhibits a minimum inhibitory concentration of 80–320 μg/mL against both standard and clinical strains of H. pylori. Triphala exerts its anti-H. pylori effect by perturbing the microstructure of H. pylori , downregulating adhesion-associated genes (alpA, alpB, babA), urease-related genes (ureA, ureB, ureE, ureF), and flagellar genes (flaA, flaB); inhibiting bacterial adhesion, biofilm formation, urease activity as well as CagA protein expression. Discussion: These findings suggest that Triphala exerts inhibitory effects on H. pylori activity through multiple mechanisms, underscoring its potential as a new drug for the prevention and treatment of H. pylori infection. [ABSTRACT FROM AUTHOR]

Urease-producing bacteria (UPB) provide inorganic nitrogen for primary producers by hydrolyzing urea, and play an important role in marine nitrogen cycle. However, there is still an incomplete understanding of UPB and their ecological functions in the cultivation environment of the red macroalgae Gracilariopsis lemaneiformis. This study comprehensively analyzed the diversity of culturable UPB and explored their effects on urea uptake by G. lemaneiformis. A total of 34 isolates belonging to four main bacterial phyla i.e. (Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria) were identified through 16S rRNA sequencing and were screened for UPB by urea agar chromogenic medium assay and ureC gene cloning. Our data revealed that only 8 strains contained urease. All of these UPB exhibited different urease activities, which were determined by the Berthelot reaction colorimetry assay. Additionally, the UPB strain (G13) isolated from G. lemaneiformis with higher urease activity was selected for co-culture with G. lemaneiformis to explore its role in promoting or inhibiting nitrogen uptake by macroalgae. The results showed a significant increase in urea consumption in the culture medium and the total cellular nitrogen in G. lemaneiformis in the UPB-co culture group compared to the sterile group. This suggests that the selected UPB strain positively influences nitrogen uptake by G. lemaneiformis. Similarly, isotopic assays revealed that the δ15N content of G. lemaneiformis was significantly higher in the UPB-co culture than in the control group, where δ15N-urea was the only nitrogen source in the culture medium. This indicates that the UPB helped G. lemaneiformis to absorb more nitrogen from urea. Moreover, the highest content of δ15N was found in G. lemaneiformis with epiphytic bacteria compared to sterilized (i.e. control), showing that epiphytic bacteria, along with UPB, have a compound effect in helping G. lemaneiformis absorb more nitrogen from urea. Taken together, these results provide unique insight into the ecological role of UPB and suggest that urease from macroalgae environment-associated bacteria might be an important player in marine nitrogen cycling. [ABSTRACT FROM AUTHOR]

Urea, calcium and urease are the primary components of enzyme-induced calcium carbonate precipitation (EICP) method. The composition of these ingredients significantly affects the content and strength of the precipitate. The objective of this study is to investigate the optimum dosage of urea–calcium chloride (CaCl2) and urease enzyme from test-tube experiments, on the calcium carbonate (CaCO3) precipitate when used with sand. The results of samples prepared using two different methods are compared using direct shear tests to note the effect of biocementation on the strength of the cemented sand. Bench-scale conductivity tests show that large urea–calcium chloride concentrations in combination with adequate urease activity improve the precipitate efficiency. The method of treatment also affects the strength of the treated sand, with the injection method being more efficient in cementing the sand particles compared to the mix-and-compact approach. While both the sample preparation methods resulted in the increase in peak friction angle and cohesion intercept, concentration of urea–calcium chloride higher than 0.75 mol/l and urease activity more than 30 kU/l reduced the overall shear strength. Precipitate strength was governed by its morphology, which varied depending on chemical concentrations and urease activity. Stress–dilatancy relationships for EICP-treated sands appear to follow Taylor's work-hypothesis. [ABSTRACT FROM AUTHOR]

Purple soil, one very representative type of agricultural land, has been widely distributed in the Sichuan Basin and the Three Gorges Reservoir area, such as Chongqing. Among them, purple soil often exhibits a loose structure, low strength, poor corrosion resistance, and water stability. Therefore, it is prone to soil and water loss under the frequent alternating action of dry and wet conditions caused by heavy rainfall and hydraulic erosion. Enzyme Induced Carbonate Precipitation (EICP) technology can be expected to effectively enhance the pore structure, strength, stiffness, and corrosion resistance of the soil, thereby achieving soil solidification. In this study, self-extracted soybean urease was used to induce calcium carbonate precipitation, in order to solidify the purple soil. A series of tube tests were carried out to investigate the relationship between temperature and urease concentration. Furthermore, an orthogonal test was conducted to explore the optimal calcium yield combination (CR group), as well as the maximum calcium production combination (CP group) under the combined influence of soybean urease concentration (A), calcium chloride concentration (B), and urea concentration (C). Subsequently, curing tests, wetting-drying cycles tests, and unconfined compressive tests were performed on the purple soil samples to investigate the impact of different curing combinations and numbers of wetting-drying cycles on sample quality, appearance, unconfined compressive strength, and stiffness. The evolving nature of the curing process was characterized to analyze its mechanism by using scanning electron microscopy (SEM), X-ray energy dispersive analysis (EDS), and low-field nuclear magnetic resonance imaging (NMR). The results showed that: 1) The yield of calcium and the productivity of calcium carbonate are dependent on the concentrations of urease, calcium chloride, and urea. The optimal combination of calcium yield (CR group) was a urease concentration of 100 g/L, a calcium chloride concentration of 1.0 mol/L, and a urea concentration of 1.5 mol/L. The maximum combination of calcium production (CP group) was a urease concentration of 150 g/L, a calcium chloride concentration of 2.0 mol/L, and a urea concentration of 2.0 mol/L. 2) EICP treatment significantly enhanced the unconfined compressive strength and stiffness of purple soil (elastic secant modulus E50). Compared with the Control group (CW group), the unconfined compressive strength increased by 104.47% in the CR group and by 60.03% in the CP group; while E50 increased by 86.36% in the CR group and by 36.56% in the CP group. The cured sample shared excellent durability after seven wetting-drying cycles. Among them, the unconfined compressive strength remained at 440.65 kPa for the CR group samples and at 507.92 kPa for the CP group samples; E50 reached 24.02 MPa for the CR group and 27.57 MPa for the CP group. 3) SEM and NMR tests were carried out to quantitatively characterize the pore structure of soil. Microscopic analysis showed that EICP was used to solidify the purple soil with generated calcium carbonate particles sized between 0.1-2.0 μm. In small pores, calcium carbonate was used to fill and cement them. While in large and medium pores, the generated calcium carbonate was provided cementation and film coating, resulting in the transformation of large pores into medium-sized ones. Thus, the proportion of small and large pores decreased greatly, while the proportion of medium pores increased. As such, a more uniform pore structure was obtained in the purple soil, in order to effectively improve its integrity and compactness. Nuclear magnetic imaging analysis also intuitively proved that the EICP technology shared a better curing effect on the purple soil. This finding can provide the scientific basis and recommendations for engineering applications, such as foundation construction, slope reinforcement, and soil erosion protection in the area of purple land. [ABSTRACT FROM AUTHOR]

Heavy metal pollution, particularly cadmium, poses severe environmental and health risks due to its high toxicity and mobility, necessitating effective remediation strategies. While both microbially induced carbonate precipitation (MICP) and humic acid adsorption are promising methods for heavy metal mitigation, their combined effects, particularly the influence of humic acid on the MICP process, have not been thoroughly investigated. This study explores the interaction between humic acid and MICP, revealing that humic acid significantly inhibits the MICP process by reducing urease activity, with the 10% humic acid treatment resulting in a 23.8% reduction in urease activity compared to the control. Additionally, while higher concentrations of humic acid did not significantly reduce cadmium ion concentrations, they did result in a slight increase in organically bound cadmium, indicating an interaction that could alter metal speciation in the soil. These findings provide important insights into the mechanisms by which humic acid affects MICP, offering a foundation for optimizing combined remediation approaches. Future research should aim to fine‐tune the balance between MICP and humic acid to enhance the overall efficiency of cadmium remediation strategies. This study contributes to the development of more effective and sustainable methods for addressing cadmium contamination. [ABSTRACT FROM AUTHOR]

Enzymatic degradation of the carcinogen ethyl carbamate (EC) and its precursor urea is a promising method for controlling EC levels in alcoholic beverages. However, limited enzymes with EC-hydrolyzing activity and low ethanol or acid tolerance hinder their practical application. Here, a new urease with urea- and EC-hydrolyzing activities from Providencia sp. LBBE was characterized. The enzyme displayed considerable ethanol tolerance, retaining 42.4% activity after 1 h of incubation with 30% (v/v) ethanol at 37 °C. It exhibited broad pH tolerance (pH 3.0–8.0), with optimal pH 7.0 for EC and 7.5 for urea. After treatment at pH 4.5 and 5.0, it retained 41.3% and 59.4% activity, respectively. The Km and Vmax for EC and urea at pH 4.5 were 515.6 mM, 33.9 µmol/(min⸱mg) and 32.0 mM, 263.6 µmol/(min⸱mg), respectively. Using 6000 U/L purified enzyme at 30 °C for 9 h, 49.8% and 81.6% of urea was removed from rice wine (pH 4.5 and 7.0), respectively. No appreciable reduction in EC was observed under identical conditions, which may be ascribed to the minimal EC affinity. This study contributes to the future realization of the effective control of EC content in alcoholic beverages. [ABSTRACT FROM AUTHOR]

The aim of the work was to evaluate the effect of soil moisture, texture and organic matter content on the edaphic microbiological, dehydrogenase, urease and acid phosphatase activity of the Mapire floodplain, State of Anzoátegui, Venezuela, which is located in an igapó. The wetland in question was segmented into three sectors according to the flood condition of each one, namely zone of maximum, medium and minimum flooding. The results suggest that dehydrogenase activity increases with waterlogging time and soil humidity, that the absence of oxygen promotes acid phosphatase activity when samples come from the zone of maximum flooding, that the zones of medium and maximum flooding could constitute suitable environments for the proliferation of anaerobic microbial life, and that acetate consumption reaches the highest values in this last area, which would be linked to methanogenic bacterial activity. Urease and acid phosphatase activity seem to have a positive relationship with organic matter content in the period of low soil humidity. Microbial activity, estimated by fluorescein diacetate hydrolysis, is maximum in the medium flood zone during edaphic low humidity season. [ABSTRACT FROM AUTHOR]

Urea is the primary source of nitrogen (N) used in agriculture. However, it has a high N loss potential through volatilization. Various mechanisms can be employed to reduce N volatilization losses by inhibiting urease. When added to urea, iodine (I) has high potential for this purpose. Thus, this study aimed to determine whether adding I to urea reduces volatilization losses and increases N uptake in maize plants. Maize plants were cultivated in greenhouse conditions for 36 days. Urea treatments were applied at 15 days of testing, including iodine-enriched urea, conventional urea, and no urea application. Additionally, a study concerning N volatilization from urea was conducted using the same treatments under the same environmental conditions. Iodine was incorporated and adhered to urea, at an I concentration of 0.2%, using potassium iodate (KIO3). Under controlled conditions and over a short period of time, it was observed that the application of iodine-enriched urea increased the chlorophyll b content, root N accumulation, and total N accumulation in maize plants compared with conventional urea. Moreover, iodine-enriched urea reduced N losses from volatilization by 11% compared with conventional urea. The reduction in N volatilization correlated positively with the increased chlorophyll b, total chlorophyll, root N accumulation, and total N accumulation favored by the iodine-enriched urea treatment. Our findings demonstrated that adding I to urea is an efficient and promising strategy to reduce N losses and increase N uptake in plants. [ABSTRACT FROM AUTHOR]

Paddy residues burning is a common practice in the sub-continent to manage paddy waste, which results in deterioration of air quality in the surrounding areas and causes smog issue. In situ decomposition could be a viable option to manage this problem. About thirteen (13) cellulose degrading bacterial strains were selected and further screened based on various enzymatic activities. Finally, two strains (GW7 and HA 121) wi th highest enzymatic potential were selected for optimization of factors to enhance cellulase production. The selected bacterial strain GW7 was found positive for urease, protease, catalase, phosphates and cellulase activity. While HA121 strain was positive for urease, protease, phosphatase and cellulase enzymes. The strains GW7 and HA121 exhibited maximum cellulose activity of 23 U mL-1 and 19 U mL-1, respectively, at optimized conditions. The optimal conditions for GW7 were temperature 35°C, pH 8, 1.5% glucose and 0.5% urea concentration. However, for HA121 the highest cellulase activity was attained when 1% glucose and 0.5% urea as co-inducers were used at a temperature of 35 °C and pH 8 where cellulase enzyme production was found to be 19 U mL-1. The optimization of cellulolytic bacterial cultures for enhanced cellulase production has established its potential utilization for field application. [ABSTRACT FROM AUTHOR]

The purpose of the work was to study the concentration of various forms of mineral nitrogen and nitrogen cycle enzymes in farmland soils. The objectives of the research included studying the content of ammonium and nitrate forms of nitrogen, as well as the activity of urease and nitrate reductase in soils of farmland on the territory of the Donetsk People's Republic (DPR). To study the soils of agricultural lands, model sites located in the southern part of the Shakhtersky district of the DPR were selected and represented by moderately washed-out chernozems with low, low and medium humus. The control was an area with steppe vegetation (ordinary chernozem, thick, with medium humus content). The results of the researches allow us to draw conclusions about the development of degradation processes in a number of model sites and their impact on the content of ammonium and nitrate nitrogen in agricultural soils. Growing crops removing substantial amount of mineral nutrients, the slope of the sites surface, and the duration of cultivation of grain crops in the same sites lead to a significant decrease in the concentration of ammonium and nitrate nitrogen. Thus, the most significant decrease in the concentration of nitrogen of ammonium compounds (by 77–82%) was recorded in model slope areas under maize and sunflower. Analysis of the data showed that exchange ammonium is confined to the underlying genetic horizons. The minimum concentration of nitrates in the arable horizon was recorded under the joint influence of such unfavorable factors as: unreasonable layout of fields along the relief elements; violation of crop rotation conditions; use of precursor crops with a significant level of removal of nutrients (wheat, maize). When studying the activity of urease, it was found that a low number of soil microorganisms associated with the cultivation of maize and sunflower, as well as with the development of degradation processes of various genesis, led to the suppression of the functioning of the urease of soils in model areas. The maximum urease activity was observed in areas under winter wheat and amounted to 68–72% in relation to the control indicators. As a result of studies of nitrate reductase activity, a decrease in its values was also found in areas used to grow crops that form a large phytomass (maize and sunflower).

Urea is the primary source of nitrogen (N) used in agriculture. However, it has a high N loss potential through volatilization. Various mechanisms can be employed to reduce N volatilization losses by inhibiting urease. When added to urea, iodine (I) has high potential for this purpose. Thus, this study aimed to determine whether adding I to urea reduces volatilization losses and increases N uptake in maize plants. Maize plants were cultivated in greenhouse conditions for 36 days. Urea treatments were applied at 15 days of testing, including iodine-enriched urea, conventional urea, and no urea application. Additionally, a study concerning N volatilization from urea was conducted using the same treatments under the same environmental conditions. Iodine was incorporated and adhered to urea, at an I concentration of 0.2%, using potassium iodate (KIO3). Under controlled conditions and over a short period of time, it was observed that the application of iodine-enriched urea increased the chlorophyll b content, root N accumulation, and total N accumulation in maize plants compared with conventional urea. Moreover, iodine-enriched urea reduced N losses from volatilization by 11% compared with conventional urea. The reduction in N volatilization correlated positively with the increased chlorophyll b, total chlorophyll, root N accumulation, and total N accumulation favored by the iodine-enriched urea treatment. Our findings demonstrated that adding I to urea is an efficient and promising strategy to reduce N losses and increase N uptake in plants.

A zeolite pot experiment was conducted at the Agricultural Research Council Infruitec-Nietvoorbij in Stellenbosch, South Africa, under greenhouse conditions. The experiment aimed to investigate the impact of zeolite application on soil enzyme activities in sandy soils cultivated with Swiss chard (Beta vulgaris Var. cicla) and cabbage (Brassica oleracea Var. capitata L.) over two years (2018-2019). Different zeolite-to-soil ratios (0:1, 1:9, 2:8, and 3:7 w/w) were used, with each pot containing 12 kg of soil. The experiment involved 72 pots for each vegetable, arranged in a randomized complete block design (RCBD). Soil enzyme activities, including acid phosphatase, β-glucosidase, and urease, as well as soil chemical properties (pH, total plant-available nitrogen, organic carbon, and phosphorus), were analyzed. Key findings indicate that the effect of zeolite application on enzyme activities varied between the vegetable species. Zeolite application significantly increased (P

Objectives: This study aimed to characterize a tigecycline-resistant hypervirulent Klebsiella pneumoniae (HvKP) strain, identified as KLZT, which carries the tigecycline resistance gene cluster tmexC2-tmexD2-toprJ2 belonging to ST29 and serotype K212. Methods: Antimicrobial susceptibility and virulence phenotypes were assessed, followed by whole-genome sequencing (WGS) using PacBio II and MiSeq sequencers. Genome annotation was carried out using the RAST server and bioinformatics analysis revealed the genetic characteristics of this strain. Results: Antimicrobial and virulence phenotype testing indicated that K. pneumoniae strain KLZT could be considered as a multidrug-resistant HvKP. WGS analysis showed that KLZT has a single 5,536,506-bp chromosome containing three plasmids 290,963 bp (pKLZT-1), 199,302 bp (pKLZT-2), and 4820 bp (pKLZT-3) in size, and also includes the ST29 and K212 serotypes. Four (blaSHV-187, oqxA, oqxB, and fosA6) and six resistance genes (tmexC2-tmxeD2-toprJ2, blaOXA-1, aac(6′)-Ib-cr, catB3, arr-3, and blaLEN27) were identified from chromosomal and plasmid pKLZT-1, respectively. Gene-based analysis of the resistance genes of plasmid pKLZT-1 showed that the tigecycline resistance gene cluster-carrying region was flanked by umuC and umuD (umuD-hps-IS5-tmexC2-tmexD2-toprJ2-umuC), as well as other resistance genes and virulence factors (ureB, ureC, and ureG), which were carried by IS5075-Tn3-intI1 -aac(6′)-Ib-cr-blaOXA-1-catB3-arr-3-blaLEN27-Tn3-ISkpn26-ureBCG-IS5075. Conclusions: WGS has revealed that a multidrug-resistant strain, HvKP KLZT, belonging to ST29 with capsular serotype K212, contains a multidrug-resistance plasmid.

Background: Treatment of Helicobacter pylori (H. pylori) infections is challenged by antibiotic resistance. The urease enzyme contributes to H. pylori colonization in the gastric acidic environment by producing a neutral microenvironment. We hypothesized that urease inhibition could affect H. pylori viability. This work aimed to assess the effects of acetohydroxamic acid (AHA), ebselen and baicalin on urease activity, bacterial viability and urease genes expression in H. pylori isolates. Methods: Forty-nine H. pylori clinical isolates were collected. Urease activity was assessed using the phenol red method. The urease inhibition assay assessed inhibitors' effects on urease activity. Flow cytometry assessed the effect of inhibitors on bacterial viability. Real time PCR was used to compare urease genes expression levels following urease inhibition. Results: Urease activity levels differed between isolates. Acetohydroxamic acid inhibited urease activity at a concentration of 2.5 mM. Although baicalin inhibited urease activity at lower concentrations, major effects were seen at 8 mM. Ebselen's major inhibition was demonstrated at 0.06 mM. Baicalin (8 mM) significantly reduced ATP production compared to untreated isolates. Baicalin, ebselen and acetohydroxamic acid significantly reduced H. pylori viability. Increased urease genes expression was detected after exposure to all urease inhibitors. Discussion: In conclusion, higher concentrations of baicalin were needed to inhibit urease activity, compared to acetohydroxamic acid and ebselen. Baicalin, ebselen and acetohydroxamic acid reduced H. pylori viability. Therefore, these inhibitors should be further investigated as alternative treatments for H. pylori infection. [ABSTRACT FROM AUTHOR]

Introduction: Paracoccus yeei is the first species in the genus Paracoccus to be implicated in opportunistic infections in humans. As a result, P. yeei strains provide a valuable model for exploring how bacteria shift from a saprophytic to a pathogenic lifestyle, as well as for investigating the role of horizontally transferred DNA in this transition. In order to gain deeper insights into the unique characteristics of this bacterium and the molecular mechanisms underlying its opportunistic behavior, a comparative physiological and genomic analysis of P. yeei strains was performed. Results: Complete genomic sequences of 7 P. yeei isolates (both clinical and environmental) were obtained and analyzed. All genomes have a multipartite structure comprising numerous extrachromosomal replicons (59 different ECRs in total), including large chromids of the DnaA-like and RepB families. Within the mobile part of the P. yeei genomes (ECRs and transposable elements, TEs), a novel non-autonomous MITE-type element was identified. Detailed genus-wide comparative genomic analysis permitted the identification of P. yeei -specific genes, including several putative virulence determinants. One of these, the URE gene cluster, determines the ureolytic activity of P. yeei strains—a unique feature among Paracoccus spp. This activity is induced by the inclusion of urea in the growth medium and is dependent on the presence of an intact nikR regulatory gene, which presumably regulates expression of nickel (urease cofactor) transporter genes. Discussion: This in-depth comparative analysis provides a detailed insight into the structure, composition and properties of P. yeei genomes. Several predicted virulence determinants (including URE gene clusters) were identified within ECRs, indicating an important role for the flexible genome in determining the opportunistic properties of this bacterium. [ABSTRACT FROM AUTHOR]

Metal ion‐based inhibition of urease activity is a promising strategy for treating Helicobacter pylori (H. pylori) infections. However, the challenges of safe delivery and reducing cytotoxicity persist. In this study, an innovative nanocarrier capable of acid‐responsive release of Ag+ and antibiotics is developed, with complete degradation after treatment. Mesoporous organosilica nanoparticle (MON) is encapsulated with hyaluronic acid (HA) to prevent drug leakage and further coated with bacterial outer membrane vesicle (OMV) from Escherichia coli Nissle 1917, creating a nanocarrier with cell‐protective capabilities. Ag+ and antibiotic clarithromycin (CLR) are incorporated into the nanocarrier to form CLR‐Ag+@MON@HA@OMV (CAMO), designed for the targeted treatment of gastric H. pylori infection. The HA encapsulation ensures acid‐responsive release of CLR and Ag+ in the stomach, preventing premature release at non‐inflammatory sites. There is a potential for Ag⁺ in CAMO to replace Ni2⁺ at the active site of urease, enhancing the bactericidal effect of CLR through urease inhibition. Furthermore, the OMV provides additional cytoprotection, mitigating cell damage and inflammation response induced by the H. pylori infection. This study introduces a safe and effective nanocarrier that eradicates H. pylori and alleviates gastric inflammation. [ABSTRACT FROM AUTHOR]

Safflower (Carthamus tinctorius L.) is a multipurpose crop and can be grown successfully under moisture-deficit environments. This study assessed the physiological attributes and yield-related traits of two safflower varieties (Dinçer and Balcı) under rainfed and irrigated environments during 2019-2020 and 2020-2021. Data relating to physiological and yield-related traits, and soil enzymes were collected. Soil attributes, nutrient acquisition, and yield-related traits were significantly altered by the interactive effect of varieties and growing environments. Higher nitrate (NO3-) accumulation (279.92 and 300 mg N g DW) was recorded in Balcı variety than Dinçer under rainfed conditions. Higher grain yield was recorded under irrigated conditions compared to rainfed environments. Balcı variety produced 2724 and 2464 kg/ha grain yield, whereas Dinçer resulted in 2664 and 2565 kg/ha under irrigated conditions during 1st and 2nd year, respectively. Nevertheless, Balcı produced a higher yield than Dinçer under rainfed conditions. The results indicate that irrigation is crucial for safflower in arid and semi-arid regions. Similarly, Dinçer variety is advantageous under rainfed conditions, whereas the Balcı variety may be more beneficial in irrigated areas. [ABSTRACT FROM AUTHOR]

Affınity based hybrid nanopolymeric membranes were developed in this work as a support material to immobilize urease. The hybrid membrane exhibits the desired characteristics and has potential applications in biotechnological and biomedical processes, particularly in artificial kidney devices that remove urea from blood. In this study, it was aimed to embed p(GMA) (glycidylmethacrylate) nanoparticles into HEMA(2‐hydroxyethylmethacrylate) membranes and use them in urease enzyme immobilization. First, p(GMA) nanoparticles were synthesized with surfactant‐free emulsion polymerization method. Then, a hybrid affinity system was developed by embedding p(GMA) nanoparticles in the p(HEMA) polymeric membranes synthesized by the free radical photopolymerization method. Following the characterization studies with dry mass analysis, scanning electron microscopy (SEM) analysis, Fourier‐transform infrared spectroscopy (FTIR) analysis, Brunauer–Emmett–Teller (BET) analysis, surface area calculations, and swelling tests of the hybrid membranes, and conditions (pH, temperature, and concentration) were optimized for urease immobilization. Urease was immobilized onto p(GMA) nanoparticles embedded in p(HEMA) hybrid membranes via adsorption. The maximum urease immobilization capacity of the p(GMA) nanoparticles embedded in p(HEMA) hybrid membranes was 31.85 µg/g. The hybrid membrane exhibits the desired characteristics and has potential applications in biotechnological and biomedical processes, particularly in artificial kidney devices that remove urea from blood. [ABSTRACT FROM AUTHOR]

Different cropping systems and nutrient management techniques impact the microbiological characteristics of soil and nutrient availability for plants. This study assessed four cropping systems—rice–wheat, cotton–wheat, pearl millet–wheat, and pearl millet–mustard in Hisar district, Haryana, using 80 soil samples (20 from each system) collected in April 2022 after the Rabi crop harvest. The cotton–wheat system had the highest accessible nitrogen (N) at 155.9 kg ha−1, while both the cotton–wheat (59.3 kg ha−1) and rice–wheat (54.0 kg ha−1) systems had higher available sulfur (S) levels compared to pearl millet–wheat (41.2 kg ha−1). Pearl millet–wheat also showed 12.4% higher potassium (K) levels than rice–wheat. The rice–wheat system exhibited the highest phosphorus (P) concentration at 54.3 kg ha−1 and greater DTPA-extractable micronutrients. Soils from the rice–wheat system had higher DTPA-extractable micronutrients (Zn, Fe, Mn, Cu) and superior microbial biomass nitrogen (MBN, 54.7 mg kg−1), urease (37.9 µg NH4+-N g−1 h−1), and alkaline phosphatase activity (APA, 269.7 µg PNP g−1 h−1) compared to other systems. Canonical discriminant functions explained 88.1% of the variability among cropping systems, while principal component analysis identified available P, DTPA-extractable Zn, and Cu as key soil quality indicators, accounting for 66.9% of the variance. These insights can inform policymakers on promoting effective cropping systems and sustainable soil health in northwestern India. [ABSTRACT FROM AUTHOR]

We construct a compartmentalized nanoarchitecture to regulate bioenergy level. Glucose dehydrogenase, urease and nicotinamide adenine dinucleotide are encapsulated inside through liquid‐liquid phase separation. ATPase and glucose transporter embedded in hybrid liposomes are attached at the surface. Glucose is transported and converted to gluconic acid catalyzed by glucose dehydrogenase, resulting in an outward proton gradient to drive ATPase for ATP synthesis. In parallel, urease catalyzes hydrolysis of urea to generate ammonia, which leads to an inward proton gradient to drive ATPase for ATP hydrolysis. These processes lead to a change of the direction of proton gradient, thus achieving artificial ATP oscillation. Importantly, the frequency and the amplitude of the oscillation can be programmed. The work explores nanoarchitectonics integrating multiple components to realize artificial and precise oscillation of bioenergy level. [ABSTRACT FROM AUTHOR]

Investigations into the use of urease inhibitors for reducing ammonia emission in dairy farming have been published in several papers. The aim of this study is to expand the existing knowledge on the use of urease inhibitors for reducing ammonia emissions in fattening pig houses. In this respect, in addition to the proven standard application approach using a backpack sprayer, the investigation was extended to include different application techniques. Urease inhibitor was applied on two farms over six experimental periods throughout the year using three different application techniques: a backpack sprayer, and a semi-automatic system that applies the inhibitor both on-floor and under-floor. Two identical compartments, alternated between treatment and control, were used on each farm. A linear mixed model with repeated measurements was used to quantify the reduction effect of the urease inhibitor. The use of the backpack sprayer led to a reduction in ammonia emissions of 22.9% (standard error, SE: 4.9%). The on-floor application system reduced the emissions by 16.6% (SE: 4.9%), and the under-floor application system resulted in no significant reduction. The development of the semi-automatic application system can be considered beneficial for reducing emissions. However, further development and improvement of this application system is necessary for its widespread practical use, especially regarding the distribution accuracy of the application liquid, contamination issues, and the manual workload. In addition, the effects of the presence of the animals during the application process need to be investigated in more detail. • Investigation of different urease inhibitor application techniques in pig houses. • A 22,9% reduction in ammonia emissions was achieved with a backpack sprayer. • On-floor application system shows a comparable reduction in ammonia emissions. • Under-floor application system showed no significant ammonia emission reduction. [ABSTRACT FROM AUTHOR]

Enzyme-induced calcite precipitation (EICP) is one of the emerging soil improvement methods. However, when plant-based enzyme is used, the urease enzyme harvested from plants cannot be stored long. This affects large-scale applications of this method. This paper presents a new method that not only enables urease enzyme to be stored for a long duration, but also improves significantly the effectiveness and efficiency of EICP for soil improvement. In this method, the storage duration of soybean derived urease enzyme is prolonged by storing it at negative 20 degrees. The experimental results indicated that the frozen-stored urease enzyme had an activity of 326% higher than that of fresh enzyme. The shear strength of a fine sand treated using the frozen-stored enzyme is 238.8% higher than that using a normal EICP method. Thus, the frozen method not only overcomes the enzyme storage problem, but also offers a much-improved EICP method. The reasons for the higher urease activity and improved strength enhancement are also explained in this paper. [ABSTRACT FROM AUTHOR]

Enzymatically induced carbonate precipitation (EICP) is widely studied as a promising technique for soil stabilization and cementation. The solidification inhomogeneity resulted from higher urease activities always hampers the wide application of EICP. To date, several methods have been developed to effectively improve the solidification homogeneity at temperatures below 60 °C; however, several practical application fields have a higher environmental temperature over 60, even reaching 75 °C. The higher urease activity and quick decay at these temperatures easily result in solidification inhomogeneity and eventually lower strengths. In this study, the combined addition of garlic extract (GE) and dithiothreitol (DTT) was proposed to solve the problem. The influence of the proposed method on urease activities and production rates for calcium carbonate (CaCO3) was investigated and the sand solidification test was conducted to further study the influence of the method on treatment effects. Results showed that the urease activity significantly decreased with the GE addition, while the urease activity increased after the DTT addition, regardless of temperatures. With a higher content of DTT, both the increasing ranges of urease activities and production rates for CaCO3 were larger. In the sand solidification test, the GE addition decreased the precipitation rate of CaCO3 at high temperatures, which was beneficial to obtain smaller differences in sonic time values and CaCO3 contents at different parts of sand columns. Subsequently, the DTT would recover urease activity to ensure a sufficient produced amount of CaCO3 and to achieve higher strength. The optimum contents of GE and DTT were different for the samples solidified at different temperatures. The proposed method had significant application potential in the fields of geotechnical and materials engineering. [ABSTRACT FROM AUTHOR]