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1.
Sci Total Environ ; 954: 176385, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39304162

RESUMEN

Microbial communities as the most important and active component of soil play a crucial role in the geochemical cycling of toxic metal(loid)s in the Pb and Zn smelting site soils. However, the relationships between soil microbial communities and the fractions of toxic metal(loid)s and the succession of soil microbial community and functions after enrichment cultivation have rarely been analyzed. In this study, the diversity and composition of microbial communities in soils before and after enrichment cultivation were investigated by high-throughput sequencing. And the co-occurrence relationships between soil microbial community after enrichment cultivation and MRGs genes were also analyzed through the BacMet database. Results showed that the dominant genus in the soils was Lactobacillus and Stenotrophomonas. The soil microbial community exhibited a notable correlation with Cd, Pb, and As, among which Cd exerted the most profound impact. Alishewanella, Pseudomonas, Massilia and Roseibacillus were significantly correlated with the fraction of Cd. After enrichment cultivation, the number of genera decrease to 96. And the dominant genus changed to Acinetobacter, Bacillus, Comamonas, Lysobacter, and Pseudoxanthomonas. High abundance of metal resistance genes (MRGs) including zntA, fpvA, zipB, cadA, czcA, czcB, czcC, zntA, arsR, pstS and pstB was found in the microbial community after enrichment cultivation. The potential host genus for MRGs was Acinetobacter, Comamonas, Lysinibacillus, Azotobacter, Bacillus, Lysobacter, Cupriavidus, Pseudoxanthomonas, and Thermomonas. Additionally, these microbial community after enrichment cultivation possessing pathways of bacterial chemotaxis and two-component systems was enabled them to adapt to the polluted environment. These observations provided potential guidance for microbe isolation and the development of strategies for the bioremediation of toxic metal(loid)s polluted soils.

2.
Sci Total Environ ; 952: 175941, 2024 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-39218086

RESUMEN

When biological nitrogen removal (BNR) systems shifted from treating simulated wastewater to real wastewater, a microbial succession occurred, often resulting in a decline in efficacy. Notably, despite their high nitrogen removal efficiency for real wastewater, anammox coupled systems operating without or with minimal carbon sources also exhibited a certain degree of performance reduction. The underlying reasons and metabolic shifts within these systems remained elusive. In this study, the simultaneous autotrophic/heterotrophic anammox system demonstrated remarkable metabolic resilience upon exposure to real municipal wastewater, achieving a nitrogen removal efficiency (NRE) of 82.83 ± 2.29 %. This resilience was attributed to the successful microbial succession and the complementary metabolic functions of heterotrophic microorganisms, which fostered a resilient microbial community. The system's ability to harness multiple electron sources, including NADH oxidation, the TCA cycle, and organics metabolism, allowed it to establish a stable and efficient electron transfer chain, ensuring effective nitrogen removal. Despite the denitrification channel's nitrite supply capability, the analysis of the interspecies correlation network revealed that the synergistic metabolism between AOB and AnAOB was not fully restored, resulting in selective functional bacterial and genetic interactions and the system's PN/A performance declined. Additionally, the enhanced electron affinity of PD increased interconversion of NO3--N and NO2--N, limiting the efficient utilization of electrons and thereby constraining nitrogen removal performance. This study elucidated the metabolic mechanism of nitrogen removal limitations in anammox-based systems treating real municipal wastewater, enhancing our understanding of the metabolic functions and electron transfer within the symbiotic bacterial community.


Asunto(s)
Procesos Autotróficos , Reactores Biológicos , Nitrógeno , Eliminación de Residuos Líquidos , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Nitrógeno/metabolismo , Reactores Biológicos/microbiología , Procesos Heterotróficos , Desnitrificación , Anaerobiosis , Oxidación-Reducción
3.
Sci Total Environ ; 953: 176091, 2024 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-39244058

RESUMEN

Sediment or soil in wetlands is regarded as an important sink of antibiotic resistance genes (ARGs). However, there are no studies on the effects of sediment changes (which caused changes in soil texture) on soil ARGs in wetland. Here, we collected topsoil samples from 12 study sites that were deposited in early (prior to the 1970s) or recent years to reveal the responses of soil ARGs to the decrease in grain size of sediment discharged into Dongting Lake. The results indicated that it caused significant increases in clay content, soil organic matter (SOM), moisture, and bacterial abundance. The absolute abundance of 38 % ARG subtypes, 62 % ARG types, and the total ARG concentrations showed a significant increase. The composition of ARG profiles also showed significant changes. For mobile genetic elements (MGEs), the levels of plasmid, insertional, and transposase were significantly elevated. Notably, clay content, moisture, SOM, and bacterial abundance presented very strong positive correlation with most ARG and total ARG abundance. The contributions of physicochemical characteristics and bacterial abundance to ARG variations were ranked as follows: 16S rRNA > SOM > moisture > pH > soil texture (clay, sand and silt) > nitrate nitrogen > ammonium nitrogen. Bacterial abundance, SOM, moisture, and soil texture were the primary environmental parameters contributing to the soil ARG variations in this research. These changes of ARGs may pose risks to ecosystems and public health.


Asunto(s)
Farmacorresistencia Microbiana , Sedimentos Geológicos , Lagos , Microbiología del Suelo , Suelo , China , Farmacorresistencia Microbiana/genética , Sedimentos Geológicos/microbiología , Lagos/microbiología , Suelo/química , Monitoreo del Ambiente , Humedales , Genes Bacterianos
4.
Sci Total Environ ; 951: 175689, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39173749

RESUMEN

The lack of electron acceptors in anaerobic sediments leads to endogenous phosphorus release and low removal efficiency of organic pollutants. This study introduced electrodes and iron oxides into sediments to construct electron network transport chains to supplement electron acceptors. The sediment total organic carbon (TOC) removal efficiencies of closed-circuit (CC) and closed-circuit with Fe addition (CC-Fe) were estimated to be 1.4 and 1.7 times of the control. Unlike the fluctuation of phosphorus in the overlying water of the controls, the CC-Fe was stabled at 0.04-0.08 mg/L during the 84-d operation. The phosphorus in interstitial water of CC-Fe was 30 % less than in control, whereas in sediment, the redox sensitive phosphorus was increased by 14 %, indicating phosphorus was preferred to fix into sediments rather than interstitial water. This is important to reduce the risk of endogenous phosphorus returning to the overlying water. Microbial community analysis showed that the multiplication of Fonticella in CC-Fe (20 %) was 1.8-fold of control (11 %) which improved the TOC removal efficiency. While electroactive microorganisms accumulated near the electrode reduced the abundance of Fe-reducing bacteria, such as Desulfitobacterium (2.4 %), leading to better phosphorus fixation. These findings suggest a strategy for the efficient bioremediation of endogenous pollution in water, with broader implications for regulating electron transport paths and element cycles in aquatic environments.


Asunto(s)
Biodegradación Ambiental , Sedimentos Geológicos , Fósforo , Contaminantes Químicos del Agua , Fósforo/análisis , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Transporte de Electrón , Compuestos Férricos
5.
Sci Total Environ ; 943: 173674, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38823701

RESUMEN

This paper investigated the operational characteristics and self-regulation mechanism of the partial denitrification/anammox (PD/A) granular system under the stress of oxytetracycline (OTC), an emerging pollutant that accumulates in municipal wastewater treatment plants through various pathways, posing significant challenges for its future promotion in engineering applications. The results indicated that OTC concentrations below 100 mg/L intensified its short-term inhibition on the PD/A granular sludge system, decreasing functional bacterial activity, while between 150 and 300 mg/L, PD's NO3--N to NO2--N conversion ability diminished, and Anammox activity was significantly suppressed. Under long-term high OTC stress (20-30 mg/L), nitrogen removal suffered, and batch tests revealed significant inhibition of PD's NO3--N to NO2--N conversion, dropping from 73.77 % to 50.17 %. Anammox bacteria activity sharply declined from 1.81 to 0.39 mg N/gVSS/h under OTC stress. Extracellular polymeric substances (EPS) content rose from 185.39 to 210.86 mg/gVSS, indicating PD/A sludge's self-protection mechanism. However, EPS content fell due to cell lysis at high OTC (30 mg/L). The decreasing relative abundance of Candidatus_Brocadia (2.32 % to 0.93 %) and Thaure (12.63 % to 7.82 %) was a key factor in the gradual deterioration of denitrification performance. This study was expected to provide guidance for the PD/A process to cope with the interference of antibiotics and other emerging pollutants (short-term shock and long-term stress).


Asunto(s)
Desnitrificación , Oxitetraciclina , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Antibacterianos , Reactores Biológicos , Aguas Residuales/química
6.
Water Res ; 256: 121624, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38669903

RESUMEN

The algal-bacterial wastewater treatment process has been proven to be highly efficient in removing nutrients and recovering nitrogen (N). However, the recovery of the valuable N-rich biopolymer, cyanophycin, remains limited. This research explored the synthesis mechanism and recovery potential of cyanophycin within two algal-bacterial symbiotic reactors. The findings reveal that the synergy between algae and bacteria enhances the removal of N and phosphorus. The crude contents of cyanophycin in the algal-bacterial consortia reached 115 and 124 mg/g of mixed liquor suspended solids (MLSS), respectively, showing an increase of 11.7 %-20.4 % (p < 0.001) compared with conventional activated sludge. Among the 170 metagenome-assembled genomes (MAGs) analyzed, 50 were capable of synthesizing cyanophycin, indicating that cyanophycin producers are common in algal-bacterial systems. The compositions of cyanophycin producers in the two algal-bacterial reactors were affected by different lighting initiation time. The study identified two intracellular synthesis pathways for cyanophycin. Approximately 36 MAGs can synthesize cyanophycin de novo using ammonium and glucose, while the remaining 14 MAGs require exogenous arginine for production. Notably, several MAGs with high abundance are capable of assimilating both nitrate and ammonium into cyanophycin, demonstrating a robust N utilization capability. This research also marks the first identification of potential horizontal gene transfer of the cyanophycin synthase encoding gene (cphA) within the wastewater microbial community. This suggests that the spread of cphA could expand the population of cyanophycin producers. The study offers new insights into recycling the high-value N-rich biopolymer cyanophycin, contributing to the advancement of wastewater resource utilization.


Asunto(s)
Microalgas , Nitrógeno , Nitrógeno/metabolismo , Microalgas/metabolismo , Bacterias/metabolismo , Reactores Biológicos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales , Proteínas Bacterianas
7.
J Hazard Mater ; 471: 134314, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640668

RESUMEN

Inorganic coagulants could effectively precipitate algae cells but might increase the potential risks of cell damage and coagulant residue. This study was conducted to critically investigate the suitability of polyaluminum (PAC), FeCl3 and TiCl4 for algae-laden water treatment in terms of the trade-off between algal substance removal, cell viability, and coagulant residue. The results showed that an appropriate increase in coagulant dosage contributed to better coagulation performance but severe cell damage and a higher risk of intracellular organic matter (IOM) release. TiCl4 was the most destructive, resulting in 60.85% of the algal cells presenting membrane damage after coagulation. Intense hydrolysis reaction of Ti salts was favorable for the formation of larger and more elongated, dendritic structured flocs than Al and Fe coagulants. TiCl4 exhibited the lowest residue level and remained in the effluents mainly in colloidal form. The study also identified charge neutralization, chemisorption, enmeshment, and complexation as the dominant mechanisms for algae water coagulation by metal coagulants. Overall, this study provides the trade-off analyses between maximizing algae substance removal and minimizing potential damage to cell integrity and is practically valuable to develop the most suitable and feasible technique for algae-laden water treatment.


Asunto(s)
Hidróxido de Aluminio , Supervivencia Celular , Compuestos Férricos , Floculación , Titanio , Purificación del Agua , Purificación del Agua/métodos , Hidróxido de Aluminio/química , Supervivencia Celular/efectos de los fármacos , Floculación/efectos de los fármacos , Compuestos Férricos/química , Titanio/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Cloruros/química
8.
Environ Res ; 252(Pt 2): 118835, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38582423

RESUMEN

Quorum sensing (QS) is prevalent in activated sludge processes; however, its essential role in the treatment of heavy metal wastewater has rarely been studied. Therefore, in this study, acyl homoserine lactone (AHL)-mediated QS was used to regulate the removal performance, enzyme activity, and microbial community of Cd- and Pb-containing wastewater in a sequencing batch reactor (SBR) over 30 cycles. The results showed that exogenous AHL strengthened the removal of Cd(II) and Pb(II) in their coexistence wastewater during the entire period. The removal of NH4+-N, total phosphorus, and chemical oxygen demand (COD) was also enhanced by the addition of AHL despite the coexistence of Cd(II) and Pb(II). Meanwhile, the protein content of extracellular polymeric substances was elevated and the microbial metabolism and antioxidative response were stimulated by the addition of AHL, which was beneficial for resistance to heavy metal stress and promoted pollutant removal by activated sludge. Microbial sequencing indicated that AHL optimized the microbial community structure, with the abundance of dominant taxa Proteobacteria and Unclassified_f_Enterobacteriaceae increasing by 73.9% and 59.2% maximally, respectively. This study offers valuable insights into the mechanisms underlying Cd(II) and Pb(II) removal as well as microbial community succession under AHL availability in industrial wastewater.


Asunto(s)
Cadmio , Plomo , Percepción de Quorum , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua , Cadmio/análisis , Percepción de Quorum/efectos de los fármacos , Plomo/análisis , Aguas del Alcantarillado/microbiología , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Aguas Residuales/química , Aguas Residuales/microbiología , Reactores Biológicos/microbiología , Acil-Butirolactonas/metabolismo , Microbiota/efectos de los fármacos , Bacterias/genética , Bacterias/efectos de los fármacos
9.
Environ Res ; 247: 118357, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38325782

RESUMEN

The widespread occurrence of organic antibiotic pollution in the environment and the associated harmful effects necessitate effective treatment method. Heterogeneous electro-Fenton (hetero-EF) has been regarded as one of the most promising techniques towards organic pollutant removal. However, the preparation of efficient cathode still remains challenging. Herein, a novel metal-organic framework (MOF)-derived Fe/Ni@C marigold-like nanosheets were fabricated successfully for the degradation of oxytetracycline (OTC) by serving as the hetero-EF cathode. The FeNi3@C (Fe/Ni molar ratio of 1:3) based hetero-EF system exhibited 8.2 times faster OTC removal rate than that of anodic oxidation and possessed many advantages such as excellent OTC degradation efficiency (95.4% within 90 min), broad environmental adaptability (satisfactory treatment performance for multiple antibiotics under various actual water matrixes), good stability and reusability, and significant toxicity reduction. The superior hetero-EF catalytic performance was mainly attributed to: 1) porous carbon and Ni existence were both conducive to the in-situ generation of H2O2 from dissolved O2; 2) the synergistic effects of bimetals together with electron transfer from the cathode promoted the regeneration of ≡ FeII/NiII, thereby accelerating the production of reactive oxygen species; 3) the unique nanosheet structure derived from the precursor two-dimensional Fe-Ni MOFs enhanced the accessibility of active sites. This work presented a promising hetero-EF cathode for the electrocatalytic treatment of antibiotic-containing wastewaters.


Asunto(s)
Estructuras Metalorgánicas , Oxitetraciclina , Contaminantes Químicos del Agua , Antibacterianos , Peróxido de Hidrógeno/química , Oxidación-Reducción , Electrodos , Contaminantes Químicos del Agua/análisis
10.
Environ Res ; 247: 118285, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266896

RESUMEN

Traditional microbial electrochemical sensors encounter challenges due to their inherent complexity. In response to these challenges, the microbial potentiometric sensor (MPS) technology was introduced, featuring a straightforward high-impedance measurement circuit tailored for environmental monitoring. Nonetheless, the practical implementation of conventional MPS is constrained by issues such as the exposure of the reference electrode to the monitored water and the absence of methodologies to stimulate microbial metabolism. In this study, our objective was to enhance MPS performance by imbuing it with unique cathodic catalytic properties, specifically tailored for distinct application scenarios. Notably, the anodic region served as the sensing element, with both the cathodic region and reference electrode physically isolated from the analyzed water sample. In the realm of organic monitoring, the sensor without Pt/C coated in the cathodic region exhibited a faster response time (1 h) and lower detection limits (1 mg L-1 BOD, 1 mM acetic acid). Conversely, when monitoring toxic substances, the sensor with Pt/C showcased a lower detection limit (0.004% formaldehyde), while the Pt/C-free sensor demonstrated superior reusability. The sensor with Pt/C displayed a heightened anode biofilm thickness and coverage, predominantly composed of Rhodococcus. In conclusion, this study introduces simple, cost-effective, and tailorable biosensors holding substantial promise for water quality monitoring.


Asunto(s)
Técnicas Biosensibles , Monitoreo del Ambiente , Electrodos , Monitoreo del Ambiente/métodos , Técnicas Biosensibles/métodos , Calidad del Agua
11.
Environ Res ; 243: 117838, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38056609

RESUMEN

The utilization of municipal sludge as a seed sludge for initiating the autotrophic nitrogen removal (ANR) process presents a challenge due to the negligible abundance of anaerobic ammonia-oxidizing bacteria (AnAOB). Here, a computational fluid dynamics model was used to simulate sludge volume fraction and sludge particle velocity. A high-height-to-diameter-ratio airlift inner-circulation partition bioreactor (HHAIPBR) was operated for 175 d to enrich AnAOB from municipal sludge, and the performance of the ANR process was investigated. The start-up period of HHAIPBR inoculated with municipal sludge required approximately 69 d. A high nitrogen removal performance, with a mean total nitrogen removal efficiency of 82.1%, was obtained for 1 month. The simulation results validated the presence of sludge circulation and revealed the distribution characteristics of dissolved oxygen inside the reactor, further supporting the promotion of sludge granulation via the high height-to-diameter ratio. Nitrosomonas (3.31%) of Proteobacteria and Candidatus Brocadia (6.56%) of Planctomycetota were dominant in the HHAIPBR. This study presents a viable approach for the industrial cultivation of anammox sludge and the rapid start-up of the partial nitritation-anammox system.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Reactores Biológicos/microbiología , Nitrógeno , Oxidación-Reducción
12.
Bioresour Technol ; 393: 130113, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38013039

RESUMEN

This article investigates the buffering capacity and recovery-enhancing ability of granular activated carbon (GAC) in a starved (influent total nitrogen: 20 mg/L) anaerobic ammonium oxidation (anammox) reactor. The findings revealed that anammox aggregated and sustained basal metabolism with shorter performance recovery lag (6 days) and better nitrogen removal efficiency (84.9 %) due to weak electron-repulsion and abundance redox-active groups on GAC's surface. GAC-supported enhanced extracellular polymeric substance secretion aided anammox in resisting starvation. GAC also facilitated anammox bacterial proliferation and expedited the restoration of anammox microbial community from a starved state to its initial-level. Metabolic function analyses unveiled that GAC improved the expression of genes involved in amino acid metabolism and sugar-nucleotide biosynthesis while promoted microbial cross-feeding, ultimately indicating the superior potential of GAC in stimulating more diverse metabolic networks in nutrient-depleted anammox consortia. This research sheds light on the microbial and metabolic mechanisms underlying GAC-mediated anammox system in low-substrate habitats.


Asunto(s)
Compuestos de Amonio , Microbiota , Carbón Orgánico , Aguas del Alcantarillado/microbiología , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Oxidación Anaeróbica del Amoníaco , Oxidación-Reducción , Anaerobiosis , Nitrógeno/metabolismo , Reactores Biológicos/microbiología , Compuestos de Amonio/metabolismo , Desnitrificación
13.
Bioresour Technol ; 390: 129891, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37863336

RESUMEN

Nitrous oxide (N2O) production is associated with ammonia-oxidizing bacteria (amoA-AOB) and denitrifying fungi (nirK-fungi) during the incorporation of biochar and biogas residue composting. This research examined the relative contribution of alterations in the abundance, diversity and structure of amoA-AOB and nirK-fungi communities on N2O emission by real-time PCR and sequence processing. Results showed that N2O emissions showed an extreme relation with the abundance of amoA-AOB (rs = 0.584) while giving credit to nirK-fungi (rs = 0.500). Nitrosomonas and Nitrosospira emerged as the dominant genera driving ammoxidation process. Biogas residue changed the community structure of AOB by altering Nitrosomonadaceae proportion and physiological capacity. The denitrification process, primarily governed by nirK-fungi, served as a crucial pathway for N2O production, unveiling the pivotal mechanism of biochar to suppress N2O emissions. C/N and NH4+-N were identified as significant parameters influencing the distribution of nirK-fungi, especially Micromonospora, Halomonas and Mesorhizobium.


Asunto(s)
Betaproteobacteria , Compostaje , Oryza , Desnitrificación , Oryza/metabolismo , Amoníaco/metabolismo , Biocombustibles , Suelo/química , Microbiología del Suelo , Óxido Nitroso/análisis , Betaproteobacteria/metabolismo , Oxidación-Reducción , Nitrificación
14.
J Infect Public Health ; 16(12): 2031-2037, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37890227

RESUMEN

BACKGROUND: Antimicrobial peptides are promising alternatives to antibiotics to treat bacterial and fungal infections, especially drug-resistant clinical pathogens. METHODS: Antimicrobial peptides (AMPs) were synthesized and antimicrobial activity was assayed. The antibacterial mechanism, ATP production, ROS generation and molecular mechanism were determined. Biofilm inhibition assay was performed in planktonic bacterial cells and biofilm degradation assay was performed using mature biofilm. The synthesized AMP2 was subjected to in vitro and in vivo analysis to analyze the safety. RESULTS: The synthesized peptides AMP1, AMP2, AMP3 and AMP4 exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria. The MIC values ranged from 1.5 ± 0.25-12.5 ± 1.25 µM and the MFC values range from 2.25 ± 0.12-25 ± 1.25 µM. F. solani showed fewer MFC values than other fungal strains. Time kill assay was performed and the AMP2 killed about 70 % of Acinetobacter baumannii at 1 × MIC concentration within 10 min incubation and killed 97 % of bacteria at 1 × MBC concentration within 15 min. The antimicrobial peptide AMP2 was highly effective against planktonic A. baumannii and L. monocytogenes. The tested AMP2 showed less toxicity to cell lines and Zebrafish. CONCLUSIONS: Antimicrobial peptides have potential antimicrobial properties against Gram-positive and Gram-negative bacteria. The in silico studies of these antimicrobial peptides are useful for eradicating drug-resistant bacteria.


Asunto(s)
Antibacterianos , Antiinfecciosos , Animales , Antibacterianos/farmacología , Antibacterianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Pez Cebra , Bacterias Gramnegativas , Bacterias Grampositivas , Antiinfecciosos/farmacología , Bacterias , Péptidos Antimicrobianos , Pruebas de Sensibilidad Microbiana , Biopelículas
15.
Front Chem ; 11: 1200469, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37408562

RESUMEN

Selective electrochemical hydrogenation (ECH) of biomass-derived unsaturated organic molecules has enormous potential for sustainable chemical production. However, an efficient catalyst is essential to perform an ECH reaction consisting of superior product selectivity and a higher conversion rate. Here, we examined the ECH performance of reduced metal nanostructures, i.e., reduced Ag (rAg) and reduced copper (rCu) prepared via electrochemical or thermal oxidation and electrochemical reduction process, respectively. Surface morphological analysis suggests the formation of nanocoral and entangled nanowire structure formation for rAg and rCu catalysts. rCu exhibits a slight enhancement in ECH reaction performance in comparison to the pristine Cu. However, the rAg exhibits more than two times higher ECH performance without compromising the selectivity for 5-(HydroxyMethyl) Furfural (HMF) to 2,5-bis(HydroxyMethyl)-Furan (BHMF) formation in comparison to the Ag film. Moreover, a similar ECH current density was recorded at a reduced working potential of 220 mV for rAg. This high performance of rAg is attributed to the formation of new catalytically active sites during the Ag oxidation and reduction processes. This study demonstrates that rAg can potentially be used for the ECH process with minimum energy consumption and a higher production rate.

16.
ACS Omega ; 8(21): 18543-18553, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37273629

RESUMEN

One of the most common diseases in women is breast cancer, which has the highest death globally. Surgery, chemotherapy, hormone treatments, and radiation are the current treatment options for breast cancer. However, these options have several adverse side effects. Recently, peptide-based drugs have gained attention as anticancer therapy. Studies report that peptides from biological toxins such as venom and virulent pathogenic molecules have potential therapeutic effects against multiple diseases, including cancers. This study reports on the in vitro anticancer effect of a short peptide, PS9, derived from a virulent protein, glycosyl hydrolase, of an aquatic fungus, Aphanomyces invadans. This peptide arrests MCF-7 proliferation by regulating intercellular reactive oxygen species (ROS) and apoptotic pathways. Based on the potential for the anticancer effect of PS9, from the in silico analysis, in vitro analyses using MCF-7 cells were executed. PS9 showed a dose-dependent activity; its IC50 value was 25.27-43.28 µM at 24 h. The acridine orange/ethidium bromide (AO/EtBr) staining, to establish the status of apoptosis in MCF-7 cells, showed morphologies for early and late apoptosis and necrotic cell death. The 2,7-dichlorodihydrofluorescein diacetate (DCFDA) staining and biochemical analyses showed a significant increase in reactive oxygen species (ROS). Besides, PS9 has been shown to regulate the caspase-mediated apoptotic pathway. PS9 is nontoxic, in vitro, and in vivo zebrafish larvae. Together, PS9 may have an anticancer effect in vitro.

17.
Aquat Toxicol ; 260: 106578, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37244123

RESUMEN

The emergence of antibiotic resistance is the most challenging factor for developing a proper drug to treat S. aureus infection. These bacterial pathogens can survive in fresh water and spread to various environments. Plant sources, especially pure compounds, are the material of interest amongst researchers for developing drugs of therapeutic value. Here, we report the bacterial clearance and anti-inflammatory potential of the plant compound Withaferin A, using the zebrafish infection model. The minimum inhibitory concentration of the Withaferin A was calculated as 80 µM against S. aureus. The DAPI/PI staining and scanning electron microscopy analysis showed the pore-forming mechanism of Withaferin A on the bacterial membrane. Along with the antibacterial activity, the results from the tube adherence test reveal the antibiofilm property of Withaferin A. In vivo studies were demonstrated to determine the effect of Withaferin A on survival, inflammatory response and behavioural changes during S. aureus infection. Staining zebrafish larvae with neutral red and Sudan black indicates a substantial decrease in the number of localized macrophages and neutrophils. The gene expression analysis showed the downregulation of inflammatory marker genes. Additionally, we observed the improvement in locomotory behaviour among Withaferin A treatment adult zebrafish. In conclusion, S. aureus can infect zebrafish and induces toxicological effect. In comparison, the results from in vitro and in vivo experiments suggest that Withaferin A can be used for synergistic antibacterial, antibiofilm and anti-inflammatory activity to treat infections due S. aureus.


Asunto(s)
Infecciones Estafilocócicas , Contaminantes Químicos del Agua , Animales , Humanos , Staphylococcus aureus , Pez Cebra , Contaminantes Químicos del Agua/toxicidad , Antibacterianos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Bacterias , Pruebas de Sensibilidad Microbiana , Biopelículas
18.
J Basic Microbiol ; 63(7): 801-813, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37057999

RESUMEN

Plant growth-promoting rhizosphere of associated fungi is often used to improve productivity and crop health. Some biocontrol fungi showed less disease protection efficiency due to environmental factors. Hence, the analysis of biocontrol fungi strains in the field is valuable to analyze their performance in the natural environment. The main objective of this study is to isolate the growth-promoting, rot disease-protecting activities of Trichoderma gamsii RH4 obtained from the rhizosphere of black gram (Vigna mungo). In this study, we evaluated the protective role of 13 fungal strains, including T. gamsii against Fusarium oxysporum in the laboratory experiment (antagonistic assay), greenhouse. The growth-promoting activity of the isolated 13 fungal strains was initially screened and the lytic property was assayed. The T. gamsii showed excellent growth-promoting and lytic properties. Lytic enzyme assays revealed a significant difference in the enzyme yield than other isolates (p < 0.05). The influence of selected plant-growth-promoting fungal strains on the suppression of F. oxysporum rot and wilt black gram was analyzed. Results revealed that these fungal isolates improved black gram growth in greenhouse and significantly reduced wilt and rot disease. The improved growth and yield registered in this study proved growth-promoting and biocontrol properties. The potent T. gamsii was applied in the open field and its effect on green gram was observed. The field trial experiment revealed several growth-promoting effects such as the weight and length of the root and shoot system. The isolated native T. gamsii has the potential to improve the biocontrol properties against rot disease.


Asunto(s)
Fusarium , Hypocreales , Trichoderma , Suelo , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología
19.
Antibiotics (Basel) ; 12(3)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36978410

RESUMEN

The Asteraceae family is one of the largest families in the plant kingdom with many of them extensively used for significant traditional and medicinal values. Being a rich source of various phytochemicals, they have found numerous applications in various biological fields and have been extensively used for therapeutic purposes. Owing to its potential phytochemicals present and biological activity, these plants have found their way into pharmaceutical industry as well as in various aspects of nanotechnology such as green synthesis of metal oxide nanoparticles. The nanoparticles developed from the plants of Asteraceae family are highly stable, less expensive, non-toxic, and eco-friendly. Synthesized Asteraceae-mediated nanoparticles have extensive applications in antibacterial, antifungal, antioxidant, anticancer, antidiabetic, and photocatalytic degradation activities. This current review provides an opportunity to understand the recent trend to design and develop strategies for advanced nanoparticles through green synthesis. Here, the review discussed about the plant parts, extraction methods, synthesis, solvents utilized, phytochemicals involved optimization conditions, characterization techniques, and toxicity of nanoparticles using species of Asteraceae and their potential applications for human welfare. Constraints and future prospects for green synthesis of nanoparticles from members of the Asteraceae family are summarized.

20.
J Infect Public Health ; 16(5): 784-791, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36958173

RESUMEN

BACKGROUND: Monkeypox virus (mpox) disease is caused by a double-stranded DNA virus from the Poxviridae family. The mpox virus showed structural similarity with smallpox virus disease. The recent outbreak of mpox infection in the rest of African countries causes public health issues of increased pandemic potential. Mpox virus is involved in the viral replication cycle through the biocatalytic reaction of precursor polyproteins cleavage. OBJECTIVES: The main objective of the study was to analyze the molecular interactions between mpox and FDA-approved drugs. METHODS: The primary and secondary structure of the protein was retrieved and FDA approved drug was screened using AutoDock. The best hit was analyzed and the molecular interactions were studied. Model validation analyzes the peptide, energy of hydrogen bonds, steric conflicts and bond planarity. Z-score was calculated using ProSA-web tool and the score tested the native fold from other alternative folds. RESULTS: The confidence level of the submitted amino acids was> 80 % and the maximum confidence score for a single template was 98.2 %. The generated proteinase model was subjected to analyze the distribution of atoms and the using ERRAT server. The overall quality score was 88.535 and this value represents the amino acid percentage with anticipated error value and the value falling below the rejection limit. The Z-score of this study result was within the Z-score range (-4.17) validated for native enzymes. The binding pockets of the enzyme were determined in this study and two binding pockets were predicted using the automatic online tool using the web server. The selected FDA-approved drugs were ordered based on their minimum binding energy to the proteinase. CONCLUSIONS: Molecular docking studies revealed the involvement of various hydrophobic interactions between FDA-approved drugs and amino acid residues of monkeypox virus proteinase.


Asunto(s)
Mpox , Péptido Hidrolasas , Humanos , Monkeypox virus , Simulación del Acoplamiento Molecular , Aminoácidos
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