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1.
Huan Jing Ke Xue ; 42(7): 3385-3391, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212664

RESUMO

A SMBBR was established to treat medium ammonium under room temperature. Results showed that TN load can reach 0.16 kg·(m3·d)-1, and the average TN removal efficiency was (51.58±6.80)% in the SMBBR with an influent ammonia concentration of 100 mg·L-1 and DO of 0.4-0.7 mg·L-1. AOB, ANAMMOX, and NOB activity reached (2253.21±502.10) mg·(m2·d)-1, (4847.46±332.89) mg·(m2·d)-1, and (1455.17±473.83) mg·(m2·d)-1, and ANAMMOX and AOB bacteria were found to develop a good collaborative relationship. Quantitative PCR results showed that the relative abundance of ANAMMOX, AOB and NOB were 11.57%, 1.01% and 0.94%, respectively. The stable operation of single stage partial nitritation-ANAMMOX process provide an alternative technology for medium ammonia wastewater.


Assuntos
Compostos de Amônio , Águas Residuárias , Reatores Biológicos , Nitrogênio , Oxirredução
2.
Huan Jing Ke Xue ; 42(7): 3422-3429, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212669

RESUMO

Cold acclimation is an effective approach for improving the nitrogen removal performance and operational stability of partial nitritation/ANAMMOX (PN/A) combined processes at low temperatures. To explore the specific effects of cold acclimation on the characteristics of sludge, differentiations in temperature sensitivity, granular morphology, composition of extracellular polymer substance (EPS), and bacterial community structure between PN/A granular sludges cultivated at medium-high temperature (30℃) and acclimated to low temperature (15℃) were investigated in this study. The results of reaction thermodynamics showed that the nitrogen removal performance of the granules acclimated to low temperature (GL) was significantly higher than that of those cultivated at medium-high temperature (GH) under the low temperature (10-20℃), and the apparent activation energy (Ea) of total inorganic nitrogen removal for the former was decreased by 28.4%. Compared with GH, GL had a smaller average particle size of 25.8% and higher EPS contents of 16.6%, resulting in a significant lower settling property. Based on the high-throughput sequencing results, GL exhibited a higher diversity of bacterial community, and a lower relative abundance ratio (0.04) of aerobic ammonium-oxidizing bacteria (Nitrosomonas) and anaerobic ammonium-oxidizing bacteria (Candidatus_Kuenenia) than 0.34 for GH. It indicated that the PN/A granules held a strong ability to retain slow-growing autotrophic bacteria in the system, even under low temperatures. These findings could provide meaningful references for analyzing the self-adaption mechanisms of PN/A sludge to low temperature conditions and promote the industrial application of combined processes.


Assuntos
Nitrogênio , Esgotos , Aclimatação , Reatores Biológicos , Desnitrificação , Nitrogênio/análise , Oxirredução
3.
Talanta ; 233: 122564, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215060

RESUMO

Photoelectrochemical (PEC) immunoassay is a burgeoning and promising bioanalytical method. However, the practical application of PEC still exist some challenges such as the inevitable damage of biomolecules caused by the PEC system and the unsatisfactory sensitivity for biomarkers with low abundance in real sample. To solve the problems, we integrated the cosensitized structure of Ag2S/ZnO nanocomposities as photoelectrode with photogenerated hole-induced chemical redox cycling amplification (CRCA) strategy to develop a split-type PEC immunosensor for cardiac troponin I (cTnI) with high sensitivity. Initially, the immunoreaction was carried out on the 96-well plates in which alkaline phosphatase (ALP) could catalyze ascorbic acid 2-phosphate (AAP) to generate the signal-reporting species ascorbic acid (AA). Subsequently, the AA participated and the tris (2-carboxyethyl) phosphine (TCEP) mediated chemical redox cycling reaction took place on the photoelectrode, thus leading to signal amplification. Under the optimized conditions, the immunosensor demonstrated a detection limit (LOD) of 3.0 × 10-15 g mL-1 with a detection range of 1.0 × 10-14 g mL-1 to 1.0 × 10-9 g mL-1 for cTnI. Impressively, the proposed method could determine the cTnI in human serum samples with high sensitivity and satisfactory accuracy. Considering the virtues of the photoelectrode and the chemical redox cycling strategy, the method would hold great potential for highly sensitive biosensing and bioanalysis.


Assuntos
Técnicas Biossensoriais , Troponina I , Fosfatase Alcalina/metabolismo , Técnicas Eletroquímicas , Humanos , Imunoensaio , Limite de Detecção , Oxirredução
4.
Talanta ; 233: 122500, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215117

RESUMO

As a biomarker of several diseases, the activity of acid phosphatase (ACP) is generally used to assistantly diagnose these diseases. Thus, developing reliable ACP activity analytical methods becomes quite significant. Herein, we recommend a one-step sampling filtration-free electrochemical method for ACP activity determination based on the target-induced synergetic modulation of tag concentration and surface passivation. Mn3O4 microspheres with favorable oxidase-mimicking activity are synthesized to catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to its product TMBox, resulting in a remarkable re-reduction signal of TMBox to TMB recorded by an integrated electrochemical system consisting of screen-printed electrode (SPE) and 3D-printed holder. When hexametaphosphate ions (HMPi) with rich negative charges are employed to interact positively charged TMBox, the formed flocculent precipitate TMBox-HMPi automatically sedimentates onto SPE surface, and both the decreased concentration of free TMBox in solution and the increased electrode surface passivation triggered by TMBox-HMPi sedimentation synergistically reduce the re-reduction signal of TMBox. When ACP is present, it hydrolyzes the HMPi substrate, greatly relieving the formation of the TMBox-HMPi precipitate and its sedimentation onto SPE surface. As a result, the electrochemical re-reduction signal of TMBox becomes remarkable again. With the strategy of using one stimulus to generate two-fold signal change, highly sensitive ACP activity detection was realized, with a wide linear range from 0.05 to 50 U/L and a limit of detection down to 0.024 U/L. Reliable monitoring of ACP activity in clinical serum was also demonstrated.


Assuntos
Técnicas Biossensoriais , Colorimetria , Fosfatase Ácida , Catálise , Técnicas Eletroquímicas , Eletrodos , Limite de Detecção , Oxirredução
5.
Anticancer Res ; 41(7): 3261-3270, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230120

RESUMO

BACKGROUND/AIM: Chronic inflammation generates large quantities of reactive oxygen and nitrogen species that damage DNA. DNA repair is important for cellular viability and genome integrity. MATERIALS AND METHODS: Expression levels of the DNA repair proteins OGG1, XPA, MLH1, PARP1, and XRCC6, which function in base excision repair, nucleotide excision repair, mismatch repair, single-strand break repair and double-strand break repair, respectively, were assessed using immunohistochemistry in ulcerative colitis and sporadic colorectal cancer biopsies. Levels of oxidative/ nitrosative stress biomarkers were also assessed. RESULTS: Ulcerative colitis and colorectal cancer lesions expressed significantly higher levels of all DNA repair proteins and oxidative/ nitrosative stress biomarkers compared to normal colonic mucosa. Ulcerative colitis had the highest XPA and XRCC6 expression. CONCLUSION: Oxidative/nitrosative stress is prevalent in the colon of both diseases. Nucleotide excision repair and non-homologous end-joining double-strand break repair may be compromised in colorectal cancer, but not in ulcerative colitis.


Assuntos
Colite Ulcerativa/genética , Neoplasias Colorretais/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , DNA/genética , Estresse Nitrosativo/genética , Estresse Oxidativo/genética , Biomarcadores Tumorais/genética , Colite Ulcerativa/patologia , Colo/patologia , Neoplasias Colorretais/patologia , Dano ao DNA/genética , Humanos , Mucosa Intestinal/patologia , Oxirredução
6.
Molecules ; 26(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207639

RESUMO

The guanyl radical or neutral guanine radical G(-H)• results from the loss of a hydrogen atom (H•) or an electron/proton (e-/H+) couple from the guanine structures (G). The guanyl radical exists in two tautomeric forms. As the modes of formation of the two tautomers, their relationship and reactivity at the nucleoside level are subjects of intense research and are discussed in a holistic manner, including time-resolved spectroscopies, product studies, and relevant theoretical calculations. Particular attention is given to the one-electron oxidation of the GC pair and the complex mechanism of the deprotonation vs. hydration step of GC•+ pair. The role of the two G(-H)• tautomers in single- and double-stranded oligonucleotides and the G-quadruplex, the supramolecular arrangement that attracts interest for its biological consequences, are considered. The importance of biomarkers of guanine DNA damage is also addressed.


Assuntos
Dano ao DNA , DNA/química , Radicais Livres/química , Quadruplex G , Guanina/química , Animais , DNA/genética , DNA/metabolismo , Elétrons , Humanos , Oxirredução , Prótons , Estereoisomerismo
7.
Bioresour Technol ; 337: 125416, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34320732

RESUMO

A novel process that combines partial nitrification, fermentation and Anammox-partial denitrification (NFAD) was proposed to co-treat ammonia rich sludge supernatant (NH4+-N = 1194.1 mg/L), external WAS (MLSS = 22092.6 mg/L) and WWTP secondary effluent (NO3--N = 58.6 mg/L). Three separated reactors were used for partial nitrification (PN-SBR), integrated fermentation and denitrification (IFD-SBR) and combined Anammox-partial denitrification (AD-UASB), respectively. The process resulted in excellent nitrogen removal efficiency (NRE) of 98.7%, external sludge reduction efficiency (SRE) of 44.6% and external sludge reduction rate of 4.1 kg/m3 after 200 days of continuous operation. IFD-SBR and AD-UASB contributed towards 89.4% and 9.2% nitrogen removal, respectively. In AD-UASB, cooperation between Anammox bacteria (4.1% Candidatus Brocadia) and partial denitrifying bacteria (3.2% Thauera) resulted in significant stability of Anammox pathway, which contributed up to 84.1% nitrogen removal in the combined Anammox-partial denitrification process. NFAD saved up to 100% organic resource demand and 25% of aeration consumption compared with the traditional nitrification-denitrification process.


Assuntos
Esgotos , Purificação da Água , Reatores Biológicos , Desnitrificação , Nitrificação , Nitrogênio , Oxirredução , Desenvolvimento Sustentável , Águas Residuárias
8.
Bioresour Technol ; 337: 125434, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34320733

RESUMO

A modified two-stage partial nitrification/anammox (PN/A) process with short aerobic HRT of 5.7 h was established and realized advanced nitrogen removal from domestic wastewater. The first process was partial nitrification in the PN-SBR, the initiation and stable maintenance of partial nitrification was achieved by pre-anaerobic treatment without inoculation or addition of inhibitor, nitrite accumulation rate was over 90% and maintained over 200 days, meanwhile pre-anaerobic improved the storage of endogenous carbon sources to enhance the nitrogen removal efficiency. The second process was anammox in the AMX-SBR, which was fed with the effluent of PN-SBR, the effluent total inorganic nitrogen was below 5 mgN/L, nitrogen removal efficiency reached 92.06%. Furthermore, Candidatus-Brocadia was enriched after treating domestic sewage with low ammonia from 0.02% to 0.23%.This study demonstrated the feasibility of starting and maintaining partial nitrification by pre-anaerobic treatment and the feasibility of nitrogen removal by coupling simultaneous-nitrification-denitrification with anammox to treat actual municipal sewage.


Assuntos
Nitrificação , Águas Residuárias , Anaerobiose , Reatores Biológicos , Desnitrificação , Nitrogênio/análise , Oxirredução , Esgotos
9.
Bioresour Technol ; 337: 125448, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34320736

RESUMO

Microbial anodes and oxygen reducing microbial cathodes were designed separately under constant polarization at + 0.1 V/SCE in a hypersaline medium (NaCl 45 g/L). They were then associated to design two-compartment microbial fuel cells (MFCs). These MFCs produced up to 209 ± 24 mW m-2 during a week. This was the first demonstration that hypersaline MFCs equipped with microbial cathodes can produce power density at this level. Desulfuromonas sp. were confirmed to be key species of the anodes. The efficiency of the cathodes was linked to the development of a redox system centred at + 0.2 V/SCE and to the presence of Gammaproteobacteria (Alteromonadales and Oceanospirillales), especially an unclassified order phylogenetically linked to the genus Thioalobacter. Comparing the different performance of the four MFCs with the population analyses suggested that polarization at + 0.1 V/SCE should be maintained longer to promote the growth of Thioalobacter on the cathode and thus increase the MFC performance.


Assuntos
Fontes de Energia Bioelétrica , Eletricidade , Eletrodos , Oxirredução , Oxigênio
10.
Bioresour Technol ; 337: 125470, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34320750

RESUMO

Low temperature is adverse to anaerobic ammonium oxidation (anammox) reaction while proper Fe addition can enhance anammox performance. Therefore, batch assays were conducted to investigate the potential effects of magnetite (100 µm, 20 µm and 200 nm) on anammox performance which were achieved from the reactor operated at 10-25 °C. After 3 runs, the results indicated that nano-scale magnetite improved the nitrogen elimination significantly. The specific anammox activity (SAA) of the group with nano-magnetite amendments was greater than the other groups after 3 runs (13.5, 12.9, 14.3, 15.4 and 15.7 mgTN/(gVSS·h)), reaching 18.0 mgTN/(gVSS·h). The distribution of magnetite in the granules were then analyzed using X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). The results indicated that nano-magnetite was more feasible to attached to the surface of the granules which might accelerate the release of Fe(II) or Fe(III) to enhance anammox performance.


Assuntos
Compostos de Amônio , Reatores Biológicos , Anaerobiose , Compostos Férricos , Óxido Ferroso-Férrico , Nitrogênio , Oxirredução , Esgotos
11.
Bioresour Technol ; 337: 125496, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34320773

RESUMO

The high-rate nitrogen removal in a continuous biofilter anammox reactor (CBAR) was investigated to treat low-concentration nitrogen wastewater. Shortening hydraulic retention time (HRT) gradually could restart CBAR and accumulate anammox bacteria effectively in the reactor, where the carmine anammox granular sludge and biofilm were coexisted well. It spent 21 days to restart CBAR completely after it had been idle for 116 days. Meanwhile, the total nitrogen removal rate remained stable at 86.42% accompanied with a total biomass concentration of 26.02 g-SS/L in 0 ~ 20 cm zone under nitrogen loading rate of 4.25 ± 0.10 kg-N/(m3·day), HRT of 20 min and 25 ℃. In addition, the specific anammox activity of biomass exceeded 0.28 g-N/(g-VSS·day) in 0 ~ 20 cm zone, which was related with a high relative abundance of Candidatus Brocadia (>30%) in the same zone. Thus, it is a feasible approach to adopt CBAR to treat low-concentration nitrogen wastewater efficiently.


Assuntos
Compostos de Amônio , Águas Residuárias , Anaerobiose , Reatores Biológicos , Desnitrificação , Nitrogênio/análise , Oxirredução , Esgotos , Temperatura
12.
Int J Mol Sci ; 22(12)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205414

RESUMO

Citrate plays a central role in cancer cells' metabolism and regulation. Derived from mitochondrial synthesis and/or carboxylation of α-ketoglutarate, it is cleaved by ATP-citrate lyase into acetyl-CoA and oxaloacetate. The rapid turnover of these molecules in proliferative cancer cells maintains a low-level of citrate, precluding its retro-inhibition on glycolytic enzymes. In cancer cells relying on glycolysis, this regulation helps sustain the Warburg effect. In those relying on an oxidative metabolism, fatty acid ß-oxidation sustains a high production of citrate, which is still rapidly converted into acetyl-CoA and oxaloacetate, this latter molecule sustaining nucleotide synthesis and gluconeogenesis. Therefore, citrate levels are rarely high in cancer cells. Resistance of cancer cells to targeted therapies, such as tyrosine kinase inhibitors (TKIs), is frequently sustained by aerobic glycolysis and its key oncogenic drivers, such as Ras and its downstream effectors MAPK/ERK and PI3K/Akt. Remarkably, in preclinical cancer models, the administration of high doses of citrate showed various anti-cancer effects, such as the inhibition of glycolysis, the promotion of cytotoxic drugs sensibility and apoptosis, the neutralization of extracellular acidity, and the inhibition of tumors growth and of key signalling pathways (in particular, the IGF-1R/AKT pathway). Therefore, these preclinical results support the testing of the citrate strategy in clinical trials to counteract key oncogenic drivers sustaining cancer development and resistance to anti-cancer therapies.


Assuntos
Ácido Cítrico/metabolismo , Neoplasias/metabolismo , Animais , Humanos , Oxirredução , Microambiente Tumoral , Efeito Warburg em Oncologia
13.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208342

RESUMO

BACKGROUND: Numerous oenological practices can cause an excess of dissolved oxygen in wine, thus determining sensory and chromatic defects in the short- to long-term. Hence, it is necessary to manage the excess of oxygen before bottling. METHODS: In this study, the management of the dissolved oxygen content by a polypropylene hollow fiber membrane contactor apparatus was performed in two wines from different grape varieties (Aglianico and Falanghina). The wines were analyzed after an 11-month aging. Anthocyanins and acetaldehyde content were evaluated by HPLC. In addition, other phenolic compounds and chromatic characteristics were analyzed by spectrophotometric methods. NMR and HR ESIMS analyses were conducted to evaluate the amount of pyranoanthocyanins and polymeric pigments. RESULTS: After 11 months of aging, in both wines a decrease of free and total SO2 with respect to initial values was detected. In the wines with the highest dissolved oxygen levels, a more remarkable loss was observed. No significant differences in terms of color parameters were detected. In red wine with the highest oxygen content, a massive formation of polymeric pigments and BSA reactive tannins was observed, as opposed to wines with lower oxygen levels. CONCLUSION: The study demonstrated that the membrane contactor can prove a successful tool to manage dissolved oxygen in wines as to prevent their oxidative spoilage.


Assuntos
Acetaldeído/química , Antocianinas/química , Oxigênio/metabolismo , Fenóis/química , Polipropilenos/química , Vitis/química , Vinho/análise , Oxirredução , Oxigênio/análise
14.
Poult Sci ; 100(8): 101232, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225206

RESUMO

Juçara (Euterpe edulis) is a native Brazilian palm tree from the Atlantic Forest, whose fruit-processing waste can present high concentration of antioxidant compounds. This research was assessed to determine the antioxidant potential of juçara waste extracts aiming to reduce the lipid and protein oxidation processes on conventional and antibiotic-free broiler meat throughout 9 d during refrigerated storage. The juçara waste extracts were obtained by microwave-assisted extraction. Two different extracts were tested based on the optimum point obtained when checking total phenolic (TPC) contents (Extract P) and antioxidant activity (Extract A) based on a previous study. The treatments using conventional and antibiotic-free broiler meat included: chicken patties without antioxidant addition (AFBNC and CBNC), with synthetic antioxidant (BHT) (AFBPC and CBPC), with Extract P (AFBEP and CBEP) and with Extract A (AFBEA and CBEA), totaling 8 treatments. Antioxidant activity of extracts along with TPC, flavonoid, anthocyanin, and tannin contents of extracts and patties were assessed. Proximate composition, fatty acid profile, lipid and protein oxidation process, and instrumental color were analyzed in patty treatments. Although both extracts had similar content of TPC and tannin, extract A presented the highest anthocyanin, while extract P exhibited the highest flavonoid. While extract A exhibited the highest antioxidant activity, extract P was highly influential in the stability of lipid oxidative degradation in both types of broiler meat (AFBEP and CBEP), and as successful as BHT (AFBPC and CBPC). In addition, extract P was also able to stabilize protein oxidation in conventional broiler meat (CBEP) from the third day, until the end of the storage period. Therefore, the fruit waste extract P of juçara can be a promising source of natural antioxidants to prevent the oxidative process in conventional and antibiotic-free broiler meat.


Assuntos
Euterpe , Animais , Antibacterianos , Antioxidantes , Brasil , Galinhas , Frutas , Carne , Oxirredução , Extratos Vegetais
15.
J Hazard Mater ; 417: 126030, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229380

RESUMO

In this work, we found that the distribution of two specific atrazine (ATZ) oxidation products (desethyl-atrazine (DEA) and desisopropyl-atrazine (DIA)) was different in oxidation processes involving aqueous ferryl ion (Fe(IV)) species and •OH. Specifically, the molar ratio of produced DEA to DIA (i.e., [DEA]/[DIA]) increased from 7.5 to 13 with increasing pH from 3 to 6 when ATZ was oxidized by Fe(IV), while the treatment of ATZ by •OH led to the [DEA]/[DIA] value of 2 which was independent of pH. Moreover, ATZ showed high reactivity towards Fe(IV) over a wide pH range, especially at near-neutral pH, at which ATZ oxidation in Fe(II)/peroxydisulfate system was even much faster than another well-defined Fe(IV) scavenger, the sulfoxides. By using this approach, it was obtained that the [DEA]/[DIA] value remained at 2 during ATZ transformation by the nitrilotriacetic acid (NTA) assisted Fenton-like (Fe(III)/H2O2) system, which was independent of solution pH and reactants dosage. This result clarified that •OH was the primary reactive intermediate formed in the NTA assisted Fe(III)/H2O2 system. This study not only developed a novel sensitive diagnostic tool for distinguishing Fe(IV) from •OH, but also provided more credible evidence to the nature of reactive intermediate in a commonly controversial system.


Assuntos
Atrazina , Compostos Férricos , Peróxido de Hidrogênio , Ácido Nitrilotriacético , Oxirredução
16.
J Hazard Mater ; 417: 126041, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229381

RESUMO

Simultaneous conversion of most harmful As(III) and Cr(VI) to their less toxic counterparts is environmentally desirable and cost-effective. It has been confirmed that simultaneous oxidation of As(III) to As(V) and reduction of Cr(VI) to Cr(III) can occur via free radical or mediated electron transfer processes. While Cr(VI) is reduced by reacting with H•, eaq-, photoelectron directly or undergoing ligand exchange with H2O2 and SO32-, As(III) is oxidized by HO•, SO4•-, O2•-, and holes (h+) in free radical process. The ability to concentrate Cr and As species on heterogeneous interface and conductivity determining the co-conversion efficiency in mediated electron transfer process. Acidity has positive effect on these co-conversion, while mediated electron transfer process is not much affected by dissolved oxygen (O2). Organic compounds (e.g., oxalate, citrate and phenol) commonly favor Cr(VI) reduction and inhibit As(III) oxidation. To better understand the trends in the existing data and to identify the knowledge gaps, this review elaborates the complicated mechanisms for co-conversion of As(III) and Cr(VI) by various methods. Some challenges and prospects in this active field are also briefly discussed.


Assuntos
Arsênio , Arsênio/toxicidade , Cromo/toxicidade , Peróxido de Hidrogênio , Oxirredução
17.
J Hazard Mater ; 417: 126152, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229411

RESUMO

Synthetic manganese oxides had been widely investigated to activate peroxymonosulfate (PMS) for contaminant removal in recent years. The generation of reactive oxygen species (ROS, e.g., radicals) was believed to be the primary PMS activation pathways. In this work, we report that natural manganese-containing minerals (NMMs) were also effective for PMS activation to degrade bisphenols in water. Moreover, a nonradical pathway different from literatures, was confirmed according to scavenging tests, electron paramagnetic resonance (EPR) characterization, chemical probing, solvent exchange, and Raman and electrochemical analysis. It was verified that PMS complexed with the mineral surface via inner-sphere interaction. This surface interaction improved its reactivity towards the probe compounds, bisphenols. Taking bisphenol AF (BPAF) as an example, its degradation rate was related to surface area and dosages of the mineral. Water constituents such as Cl-, HCO3-, and NOM had negligible impact on BPAF removal. The activity of the mineral was kept in an 80-hour continuous flow test. The PMS/NMM coupled oxidation degraded BPAF through direct electron transfer, and the degradation intermediates further underwent hydroxylation, bond cleavage, H-atom substitution, aromatic ring-opening, and decarboxylation. Consequently, eco-toxicity of BPAF can be reduced during the oxidation.


Assuntos
Manganês , Peróxidos , Minerais , Oxirredução
18.
Biomed Pharmacother ; 139: 111718, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34243619

RESUMO

BACKGROUND: The field bean (Vicia faba) is a valuable fodder plant of the Fabaceae family, grown as a main crop for its seed yield. Its phytochemical profile is characterized by the presence of a range of compounds with various biological activities. PURPOSE: The present study investigates the phytochemical profile of the extract from mature seeds of Vicia faba var. minor and examines its impact on preventing oxidative damage to various lipids, protein and DNA molecules in vitro. METHODS: Human plasma was treated with H2O2/Fe (an OH. donor) to induce oxidative damage to lipids and proteins, and the plant extract was then added. As oxidative stress may influence the biological activity of plasma, e.g. coagulation, and influence cardiovascular disease, the study also examined the effect of the plant extract on coagulation and monoamine oxidase activity (MAO, EC 1.4.3.4). RESULTS: The tested extract exerted a protective effect on plasma lipids and proteins treated with H2O2/Fe. However, while it appears to effectively protect the DNA in peripheral blood mononuclear cells from oxidative damage, it did not induce changes in the coagulation process, and significantly reduced MAO activity when applied at 1, 5, and 10 µg/mL. It is possible that the observed antioxidant potential may be due to the complex chemical composition of the extract: the phytochemical profile demonstrated a range of phenolic compounds, including catechins. CONCLUSION: Our findings indicate that extract from mature seeds of V. faba var. minor may be a promising source of antioxidants in multiple applications, including diseases associated with oxidative stress; however, more studies based on in vitro and in vivo models are needed to determine its biological properties.


Assuntos
Antioxidantes/fisiologia , Células Sanguíneas/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Sementes/química , Vicia faba/química , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia
19.
Molecules ; 26(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200914

RESUMO

Flavonoids are a group of secondary metabolites derived from plant-based foods, and they offer many health benefits in different stages of several diseases. This review will focus on their effects on ion channels expressed in vascular smooth muscle during atherosclerosis. Since ion channels can be regulated by redox potential, it is expected that during the onset of oxidative stress-related diseases, ion channels present changes in their conductive activity, impacting the progression of the disease. A typical oxidative stress-related condition is atherosclerosis, which involves the dysfunction of vascular smooth muscle. We aim to present the state of the art on how redox potential affects vascular smooth muscle ion channel function and summarize if the benefits observed in this disease by using flavonoids involve restoring the ion channel activity.


Assuntos
Aterosclerose/tratamento farmacológico , Flavonoides/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Animais , Aterosclerose/metabolismo , Progressão da Doença , Humanos , Canais Iônicos/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Oxirredução/efeitos dos fármacos
20.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203700

RESUMO

Fullerene is a nanosized carbon structure with potential drug delivery applications. We studied the bioeffects of a water-soluble fullerene derivative, fullerenol, with 10-12 oxygen groups (F10-12); its structure was characterized by IR and XPS spectroscopy. A bioluminescent enzyme system was used to study toxic and antioxidant effects of F10-12 at the enzymatic level. Antioxidant characteristics of F10-12 were revealed in model solutions of organic and inorganic oxidizers. Low-concentration activation of bioluminescence was validated statistically in oxidizer solutions. Toxic and antioxidant characteristics of F10-12 were compared to those of homologous fullerenols with a higher number of oxygen groups:F24-28 and F40-42. No simple dependency was found between the toxic/antioxidant characteristics and the number of oxygen groups on the fullerene's carbon cage. Lower toxicity and higher antioxidant activity of F24-28 were identified and presumptively attributed to its higher solubility. An active role of reactive oxygen species (ROS) in the bioeffects of F10-12 was demonstrated. Correlations between toxic/antioxidant characteristics of F10-12 and ROS content were evaluated. Toxic and antioxidant effects were related to the decrease in ROS content in the enzyme solutions. Our results reveal a complexity of ROS effects in the enzymatic assay system.


Assuntos
Antioxidantes/farmacologia , Fulerenos/farmacologia , Fulerenos/toxicidade , Oxigênio/química , Cinética , Luminescência , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
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