Liquid Chromatography Time-of-flight Mass Spectrometry Research Articles

Ferrate(VI) oxidation of substituted nitrobenzene compounds: Kinetics, degradation, and oxidized products

Nitrobenzene pollutants are discharged in large quantities into water bodies, posing a serious threat to the ecological environment. However, the effects of the nitrobenzene compounds with different structures on the Fe(VI) degradation process remain unclear. This research selects four different substituted nitrobenzene compounds (1,2-dinitrobenzene (1,2-DB), 4-nitrochlorobenzene (4-NCB), pentachloronitrobenzene (PCT), and 3,4-dinitrochlorobenzene (3,4-DTB)) and explores the oxidative degradation effect of ferrate(VI) based on experimental results and theoretical calculations. The reaction of Fe(VI) (800 μM) with each of the four nitrobenzene compounds (40 μM) reflected second-order reaction kinetics at pH 8: 4-NCB (127.08 M−1s−1) > PCT (113.13 M−1s−1) > 1,2-DB (100.1 M−1s−1) > 3,4-DTB (96.459 M−1s−1). Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) analysis detected the main intermediates, which consisted of hydroxylation, ring-opening, coupling, and amine-based products. Free radicals in the reaction system were identified and analyzed, and hydroxyl radicals and carbon dioxide radicals were found. In addition, density functional theory (DFT) was used to explore the degradation mechanisms in the reaction between each of the four substances and hydroxyl radicals, with the active sites of the nitrobenzenes during the Fe(VI) degradation process determined through the calculation of molecular descriptors. Toxicity analysis with ECOSAR software indicated Fe(VI) reduced the toxicity of the nitrobenzenes. This study provides experimental and theoretical support for the reaction mechanism between nitrobenzenes and Fe(VI), as well as further understanding of the degradation mechanism of nitrobenzene compounds.

Suspension cell cultures of Panax vietnamensis as a biotechnological source of ginsenosides: growth, cytology, and ginsenoside profile assessment.

Panax vietnamensis is a valuable medicinal plant and a source of a broad spectrum of biologically active ginsenosides of different structural groups. Overexploitation and low adaptability to planation cultivation have made this species vulnerable to human pressure and prompted the development of cell cultivation in vitro as a sustainable alternative to harvesting wild plants for their bioactive components. Despite high interest in biotechnological production, little is known about the main factors affecting cell growth and ginsenoside biosynthesis of this species under in vitro conditions. In this study, the potential of cell cultures of P. vietnamensis as a biotechnological source of ginsenosides was was assessed. Six suspension cell lines that were developed from different sections of a single rhizome through a multi-step culture optimization process and maintained for over 3 years on media with different mineral salt base and varying contents of auxins and cytokinins. These cell lines were evaluated for productivity parameters and cytological characteristics. Ginsenoside profiles were assessed using a combination of the reversed-phase ultra-high-performance liquid chromatography-Orbitrap-tandem mass spectrometry (UHPLC-Orbitrap-MS/MS) and ultra-performance liquid chromatography-time of flight-mass spectrometry (UPLC-TOF-MS). All lines demonstrated good growth with a specific growth rate of 0.1-0.2 day-1, economic coefficient of 0.31-0.70, productivity on dry weight (DW) of 0.30-0.83 gDW (L·day)-1, and maximum biomass accumulation varying from 10 to 22 gDW L-1. Ginsenosides of the protopanaxadiol (Rb1, Rb2/Rb3, malonyl-Rb1, and malonyl-Rb2/Rb3), oleanolic acid (R0 and chikusetsusaponin IV), and ocotillol (vinaginsenoside R1) groups and their isomers were identified in cell biomass extracts. Chikusetsusaponin IV was identified in P. vietnamensis cell culture for the first time. These results suggest that suspension cell cultures of Vietnamese ginseng have a high potential for the biotechnological production of biomass containing ginsenosides, particularly of the oleanolic acid and ocotillol groups.

Improved Formation of Biomethane by Enriched Microorganisms from Different Rank Coal Seams.

The influence of enrichment of culturable microorganisms in in situ coal seams on biomethane production potential of other coal seams has been rarely studied. In this study, we enriched culturable microorganisms from three in situ coal seams with three coal ranks and conducted indoor anaerobic biomethane production experiments. Microbial community composition, gene functions, and metabolites in different culture units by 16S rRNA high-throughput sequencing combined with liquid chromatography-mass spectrometry-time-of-flight (LC-MS-TOF). The results showed that biomethane production in the bituminous coal group (BC)cc resulted in the highest methane yield of 243.3 μmol/g, which was 12.3 times higher than that in the control group (CK). Meanwhile, Methanosarcina was the dominant archaeal genus in the three experimental groups (37.42 ± 11.16-52.62 ± 2.10%), while its share in the CK was only 2.91 ± 0.48%. Based on the functional annotation, the relative abundance of functional genes in the three experimental groups was mainly related to the metabolism of nitrogen-containing heterocyclic compounds such as purines and pyrimidines. Metabolite analysis showed that enriched microorganisms promoted the degradation of a total of 778 organic substances in bituminous coal, including 55 significantly different metabolites (e.g., purines and pyrimidines). Based on genomic and metabolomic analyses, this paper reconstructed the heterocyclic compounds degradation coupled methane metabolism pathway and thereby preliminarily elucidated that enriched culturable bacteria from different coal-rank seams could promote the degradation of bituminous coal and intensify biogenic methane yields.

Degradation of Butylated Hydroxyanisole by the Combined Use of Peroxymonosulfate and Ferrate(VI): Reaction Kinetics, Mechanism and Toxicity Evaluation.

Butylated hydroxyanisole (BHA), a synthetic phenolic antioxidant (SPA), is now widely present in natural waters. To improve the degradation efficiency of BHA and reduce product toxicity, a combination of peroxymonosulfate (PMS) and Ferrate(VI) (Fe(VI)) was used in this study. We systematically investigated the reaction kinetics, mechanism and product toxicity in the degradation of BHA through the combined use of PMS and Fe(VI). The results showed that PMS and Fe(VI) have synergistic effects on the degradation of BHA. The effects of operational factors, including PMS dosage, pH and coexisting ions (Cl-, SO42-, HCO3-, K+, NH4+ and Mg2+), and different water matrices were investigated through a series of kinetic experiments. When T = 25 °C, the initial pH was 8.0, the initial BHA concentration was 100 μM, the initial concentration ratio of [PMS]0:[Fe(VI)]0:[BHA]0 was 100:1:1 and the degradation rate could reach 92.4% within 30 min. Through liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) identification, it was determined that the oxidation pathway of BHA caused by PMS/Fe(VI) mainly includes hydroxylation, ring-opening and coupling reactions. Density functional theory (DFT) calculations indicated that •OH was most likely to attack BHA and generate hydroxylated products. The comprehensive comparison of product toxicity results showed that the PMS/Fe(VI) system can effectively reduce the environmental risk of a reaction. This study contributes to the development of PMS/Fe(VI) for water treatment applications.

3D spherical CuO@g-C3N4 composites activating peroxymonosulfate for high efficient degradation of 2,4,6-trichlorophenol: The mechanism of 1O2 generation

A series of CuO@g-C3N4 composites with different contents of g-C3N4 and different morphologies of CuO have been designed and prepared by hydrothermal method and applied to activate peroxymonosulfate (PMS) for the removal 2,4,6-trichlorophenol (2,4,6-TCP). The results showed that 3D spherical shape CuO-1@g-C3N4-3, being able to activate PMS to produce a large amount of singlet oxygen (1O2), not only had good catalytic performance, but also reduced the dissolution of Cu2+. By comparing the morphological characteristics, catalytic performance, free radical species, decomposition rate of PMS and surface properties of three kinds of CuO, the generation mechanism of 1O2 and key reasons of CuO for producing 1O2 were deeply explored and finally deduced. Besides, under the conditions of initial pH 7.0, catalyst dosage 50 mg·L−1, PMS dosage 0.3 mmol·L−1 and initial concentration of 2,4,6-TCP 10 mg·L−1, the removal rate of 2,4,6,-TCP reached 94 % at 25 min in the first cycle, and 85 % in the fifth cycle. When CuO-1@g-C3N4 was applied in actual water samples, 65 % of 2,4,6-TCP was removed in the Yangtze River, and 60 % of 2,4,6-TCP in Xuanwu and Yueya Lake in 40 min. Quenching experiments and electron paramagnetic resonance (EPR) were used to indentify active species during degradation process and the degradation intermediates of 2,4,6-TCP and possible degradation pathways were determined and proposed by high performance liquid chromatography-time of flight-mass spectrometry (HPLC-TOF-MS2). This study shed light on the 1O2 generation mechanism of catalyst and provided theoretical basis and guidance for the design of 1O2 catalysts rich in non-radical active species.

B-337 Case Report: Fatal Opioid Overdose Induced by Over-the-Counter Cold Medication Diphenhydramine

Abstract Background Accidental drug-related deaths frequently arise following ingestion of multiple co-intoxicants, including opioid analgesics. Hydrocodone, the most prescribed opioid for pain management, is metabolized by hepatic enzymes CYP2D6 and CYP3A4 to the pharmacologically active metabolite hydromorphone and the inactive metabolite norhydrocodone, respectively. As a result, inhibition of CYP2D6 by other pharmacologic agents can impair the analgesic properties of hydrocodone and prolong its half-life in circulation. One such example is diphenhydramine, which is a potent inhibitor of CYP2D6 activity. This case highlights a drug-drug interaction likely resulting in an accidental fatal opioid overdose. Case Presentation A 58-year-old female had longstanding prescriptions for hydrocodone/acetaminophen (Norco® 10/325), alprazolam, carisoprodol, and diltiazem. The decedent had recently taken an over-the-counter cold medication, diphenhydramine (Benadryl), shortly preceding death. A toxicology report (NMS labs, Horsham, PA) from a post-mortem femoral blood sample detected the presence of the following therapeutic compounds by High Performance Liquid Chromatography/Time of Flight-Mass Spectrometry (LC/TOF-MS) analysis: acetaminophen (14 μg/mL), hydrocodone (410 ng/mL), dihydrocodeine (hydrocodol, 24 ng/mL), alprazolam (42 ng/mL), carisoprodol (88 ng/mL), diltiazem (110 ng/mL), and diphenhydramine (150 ng/mL). Hydromorphone, the active metabolite of hydrocodone, was not detected (<2 ng/mL). With the exception of hydrocodone, which was present at fatal concentrations, all other compounds were within therapeutic range. Together, these observations are strongly suggestive of a drug-drug interaction leading to impaired hydrocodone metabolism. Conclusions This case report highlights a fatal opioid overdose as a result of CYP2D6 inhibition by diphenhydramine, a readily available over-the-counter medication. Post-mortem toxicological analysis revealed hydrocodone was present in lethal concentrations, whereas its pharmacologically active metabolite, hydromorphone, was undetectable at time of autopsy. Further, the patient was prescribed a formulation of hydrocodone in combination with acetaminophen, which was present at therapeutic concentrations despite the two drugs having similar elimination half-lives. These toxicological findings suggest administration of diphenhydramine precipitated a deadly accumulation of hydrocodone in the deceased. Overall, this case report underscores the importance of understanding and preventing harmful drug-drug interactions in patients taking opioid medications for pain management.

An approach to quantify ortho-phthalaldehyde contamination on work surfaces.

Ortho-phthalaldehyde (OPA) is used as a high-level disinfectant for reusable medical devices in healthcare settings. The ACGIH recently adopted a Threshold Limit Value-Surface Limit (TLV-SL; 25 µg/100 cm2) for OPA surface contamination to prevent induction of dermal and respiratory sensitization following dermal exposure. However, there is no current validated method to measure OPA surface contamination. This study aimed to develop a standardized approach for sample collection and quantitative determination of OPA from work surfaces for use in risk assessment practices. The reported method utilises readily available commercial wipes to collect surface samples coupled with direct detection of OPA via liquid chromatography time of flight mass spectrometry (LC-ToF-MS). This approach avoided complex derivatization steps commonly required for the analysis of aldehydes. Method evaluation was conducted in accordance with the Occupational Safety and Health Administration (OSHA) surface sampling guidelines. Overall recoveries of 25 µg/100 cm2 of OPA from stainless steel and glass surfaces were 70% and 72%, respectively. The reported LOD for this method was 1.1 µg/sample and the LOQ was 3.7 µg/sample. OPA remained stable on the sampling medium for up to 10 days, when stored at 4 °C. The method was demonstrated in a workplace surface assessment at a local hospital sterilising unit, successfully detecting OPA on work surfaces. This method is intended to supplement airborne exposure assessment and provide a quantitative assessment tool for potential dermal exposure. When used in conjunction with a thorough occupational hygiene program that includes hazard communication, engineering controls, and personal protective equipment, skin exposure and consequent sensitization risks in the workplace can be minimized.

Superior bensulfuron-methyl degradation performance of sphercial magnetic Co3O4@C-500/peroxymonosulfate system by enhancing singlet oxygen generation: The effect of oxygen vacancies

Singlet oxygen (1O2) could enhance the organic pollutant degradation ability due to its high selective oxidation of electrophilic compounds. Magnetic Co3O4 spheres embedded in carbon oxides (Co3O4@C-500) with oxygen vacancies were designed and synthesized by hydrothermal method and heat treating, which enhanced electronic transfer and contributed to the generation of 1O2, improving the organic pollutants degradation performance. 1O2 was produced by the reaction between oxygen vacancies and dissolved oxygen mainly, accompanying by oxygen vacancies activating PMS alone for small portion. Co3O4@C-500/PMS system could be applied in a wide pH range for the efficient removal of bensulfuron methyl (BSM). Co3O4@C-500 was magnetic and could be collected by a magnet and rapidly separated from degradation solution, displaying strong stability and good reusability. Possible degradation mechanism of BSM were explored in detail. The BSM degradation intermediates were identified by High Performance Liquid Chromatography-Time of Flight-Mass Spectrometry (HPLC-TOF-MS2) and the degradation pathways were proposed. This study shed light on the 1O2 generation mechanism of catalyst containing oxygen vacancies and gave a guide to the design and preparation of highly efficient multifunctional catalysts.

A fatal mono-intoxication with 4-fluoroisobutyrylfentanyl: Case report with postmortem concentrations.

We report on a case of a 35-year-old man who died suddenly and unexpectedly due to a 4-fluoroisobutyrylfentanyl (4-FIBF) mono-intoxication. Pathological, toxicological and chemical investigations were conducted at the Netherlands Forensic Institute. A full three-cavity forensic pathological examination was performed according to international guidelines. Biological samples obtained during autopsy were comprehensively investigated for the presence of toxic substances using headspace gas chromatography (GC) with flame ionization detection, liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS), GC-MS, high-performance LC with diode array detection and LC-tandem MS (LC-MS-MS). The seized crystalline substance found next to the body was investigated using a presumptive color test, GC-MS, Fourier-transform infrared spectroscopy and nuclear magnetic resonance. Pathological investigation identified minor lymphocytic infiltrates in the heart, considered irrelevant for the cause of death. Toxicological analysis of the victims' blood indicated the presence of a fluorobutyrylfentanyl (FBF) isomer, with no other compounds detected. The FBF isomer was identified in the seized crystalline substance as 4-FIBF. 4-FIBF concentrations were quantified in femoral blood (0.030 mg/L), heart blood (0.12 mg/L), vitreous humor (0.067 mg/L), brain tissue (>0.081 mg/kg), liver tissue (0.44 mg/kg) and urine (approximately 0.01 mg/L). Based on the outcomes of the pathological, toxicological and chemical investigations, the cause of death of the deceased was attributed to a fatal 4-FIBF mono-intoxication. The presented case underlines the added value of a combined bioanalytical and chemical investigative approach to identify and subsequently quantify fentanyl isomers in postmortem cases. Furthermore, it demonstrates the importance of investigating the postmortem redistribution of novel fentanyl analogs to establish reference values and to subsequently allow for correct interpretation of cause of death analysis in future casework.

Milking performance and plant specialized metabolites in the milk of goats fed silage from willow (Salix acmophylla) irrigated with saline water

Willow trees irrigated with recycled water yields fodder of good nutritional value that can be ensiled to provide feed year-round for dairy goats. We investigated the nutritional value of silage from willow irrigated with saline water (Electrical Conductivity 4.0) in a cross-over experiment (twenty eight goats, two periods). We compared total dry matter intake (TDMI), milking performance and milk composition, with a focus on plant phenolic compounds, of Damascus goats fed oats and vetch hays as the sole source of roughage (all-hay) or oats hay with willow silage, with 470 g/kg DM concentrates. Willow silage represented 175 and 205 g/kg of TDMI in the last five days of periods 1 and 2, respectively. Individual TDMI tended (P<0.06) to be 3.7% lower in the willow-fed goats. Milk yield, and the milk contents and daily yields of fat, protein and lactose did not differ between treatments. However, willow consumption was associated with lower contents of milk urea (P<0.02) and 59% higher anti-oxidative capacity (P<0.04). Consumption of willow silage was associated with higher levels of plasma malondialdehyde, but did not affect leucocyte clustering. We assessed the contents of plant specialized metabolites (PSMs) in the feeds and in the milk of five goats of each treatment at the end of period 2 by liquid chromatography / time-of-flight / mass spectrometry (LC-TOF-MS), with exact or tentative compound identification, depending on availability of appropriate standards. Although many flavonoids were present in feeds, they were not found in the milk of either treatment. Major phenolic compounds, including the salicinoids salicin, esculetin and chaenomeloidin found in feeds, were not recovered in milk but salicylic acid, found in all feeds, was present equally in the milk of both control and treated goats. Only two compounds directly related to the metabolism of salicin, i.e., salicylic acid and saligenin, were found in milk. Overall, milk from willow silage-fed goats contained more phenolic compounds, including benzyl alcohol, hydroquinone, methyl-syringate (P<0.001), and a saligenin derivative (P<0.005), and tended to contain more 4-hydroxybenzoic acid and hippuric acid (P<0.10) than milk from all-hay fed goats. Volcano plot-to-target changes in milk metabolites related to willow (untargeted LC-TOF-MS) showed intense upregulation of sulfated derivatives of phenolics. Growing willow for silage for dairy goats is an appropriate way to produce feed where saline water irrigation is available.

Studies of caprolactam and cyclic oligomer content, molecular weight, and thermal properties during melt post-polycondensation of polycaprolactam in the film state

In industrial application of polycaprolactam, the content of caprolactam monomer and oligomers, as well as their average molecular weight are the key factors. In this work, a liquid-chromatography/time-of-flight mass spectrometry (LC-TOF-MS) method and an advanced polymer chromatography/multi-angle laser light scattering/refractive index detector (APC-MALLS-RID) hyphenated technique have been developed as a quantitative analysis method for monomer and cyclic oligomers, and a means of determining the molecular weight of polycaprolactam. The melt post-polycondensation reaction characteristics of polycaprolactam films and the variation in monomers and cyclic oligomers (C2–C7) content have been systematically investigated. The results showed excellent repeatability and stability of quantitative test results on monomers and cyclic oligomers in polycaprolactam. The content of monomers and cyclic oligomers in the polycaprolactam decreased from 10.21% to 1.52% at 260 °C and 50 Pa for 60 min, and the average molecular weight increased from 1.53×104 g/mol to 2.36×104 g/mol. Additionally, the results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) experiments showed that the thermal stability and crystallization properties of polycaprolactam were improved after the film melt post-polycondensation reaction. Thus, this melt post-polycondensation method can realize the efficient removal of monomers and cyclic oligomers (compared with the traditional hot water extraction method) and afford high-quality polycaprolactam with high average molecular weight.

Electrochemical degradation of 10,11-dihydro-10-hydroxy carbamazepine as the main metabolite of carbamazepine.

10,11-Dihydro-10-hydroxy carbamazepine has been degraded in deionized water and wastewater samples using an electrochemical process. The anode used in the treatment process was graphite-PVC. Different factors such as initial concentration, NaCl amount, type of matrix, applied voltage, role of H2O2, and pH solution were investigated in the treatment of 10,11-dihydro-10-hydroxy carbamazepine. From the outcome of the results, it was noticed that the chemical oxidation of the compound followed a pseudo-first-order reaction. The rate constants were ranged between 22 × 10-4 and 483 × 10-4min-1. After electrochemical degradation of the compound, several by-products were raised, and they were analyzed using an accurate instrument, liquid chromatography-time of flight-mass spectrometry (LC-TOF/MS). In the present study, the treatment of the compound was followed by high energy consumption under 10V and 0.5g NaCl, reaching up to 0.65 Wh mg-1 after 50min. The inhibition of E. coli bacteria after incubation of the treated 10,11-dihydro-10-hydroxy carbamazepine sample was investigated in terms of toxicity.

Degradation of deoxynivalenol in wheat by double dielectric barrier discharge cold plasma: identification and pathway of degradation products.

Deoxynivalenol (DON) produced during the onset of fusarium head blight not only affects the quality and safety of wheat but also causes serious harm to human and livestock health. However, due to the high stability of DON, it is difficult to eliminate it or reduce it naturally after it has been produced. Cold plasma technology is a non-thermophysical processing technology that has been widely used for microbial inactivation and mycotoxin degradation. In this study, the degradation efficiency of double dielectric barrier discharge (DDBD) cold plasma on DON in aqueous solution and wheat was studied; the structures of degradation products of DON and its pathway were clarified, and the effect of DDBD plasma on wheat quality was evaluated. Double dielectric barrier discharge cold plasma was used for efficient degradation of DON (0.5 ~ 5μgmL^-1) solution and achieved a degradation rate of 98.94% within 25 min under the optimal conditions (voltage 100 V, frequency 200 Hz, duty cycle 80%). Furthermore, 10 degradation products (C15 H24 O5 , C15 H22 O6 , C15 H22 O9 , C16 H22 O7 , C15 H20 O7 , C15 H20 O9 , C15 H18 O8 , C15 H22 O5 , C16 H24 O5 , and C15 H18 O9 ) were identified by ultra-performance liquid chromatography-time of flight-mass spectrometry (UPLC-TOF-MS/MS) combined with Metabolitepilot and Peakview software. The degradation pathway of DON was obtained based on the chemical structures and accurate mass of these products. The DON degradation rate of 61% in wheat was achieved after treatment for 15 min, which slightly affects the moisture content, proteins, and wheat starch. Applying DDBD to wheat could effectively reduce the level of DON contamination, which provides a theoretical basis for applying cold plasma to the degradation of DON in wheat. © 2022 Society of Chemical Industry.

Untargeted secondary metabolite profiling and putative pathway deduction of a marine Ochrophyte – Iyengaria stellata (Børgesen) using liquid chromatography-mass spectrometry

This study divulges biochemical traits, mineral makeup, and the secondary metabolite outline of the less explored Ochrophyte, Iyengaria stellata (Børgesen) using untargeted metabolite profiling along the Pingleshwar coast, Kachchh, India. Macro mineral Na (4921.33 ± 0.577 mg/100 g Dry Weight) and micro mineral Fe (859.76 ± 0.98 mg/100 g DW) were found to be in the highest quantities. A total of 108 putative metabolites were detected using both, the positive electrospray ionization mode (+ESI) and negative electrospray ionization mode (–ESI of the Liquid Chromatography-Mass Spectrometry-Time of Flight (LCMS-TOF). The identified metabolites included steroids, terpenoids, ketones, esters, polyphenols, anthraquinones, tocopherol, etc. The metabolomics data obtained from the +ESI mode led to the inference of a putative glycerophospholipid metabolism pathway that shall provide valuable insights for future metabolic engineering studies. This study highlights the first attempt to decipher the secondary metabolite composition of I. stellata thereby further accounting for its potential as a natural source in pharmaceutical and nutraceutical compositions.

Mixed oxidation of chlorophene and 4-tert-butylphenol by ferrate(VI): Reaction kinetics, cross-coupling products and improved utilization efficiency of ferrate(VI)

As two representative phenolic pollutants, chlorophene (CP) and 4-tert-butylphenol (4-tBP) are used in large quantities and could have adverse effects on aquatic organisms and even human health. Due to their co-occurrence in water and wastewater, the oxidative degradation of mixed solution of the two phenols by ferrate (Fe(VI)) was systematically investigated in this work. Compared with the single solution, the kapp values of CP and 4-tBP were increased by 15.7% and 91.9%, respectively in the mixed solution, and the calculated reaction stoichiometric efficiency (RSE) was also improved by more than one time. The reaction intermediates were identified by liquid chromatography-time-of-flight-mass spectrometry (LC-TOF-MS) analysis, from which three possible pathways including direct oxidation, oxygen transfer, ring opening and coupling reaction were proposed for mixed transformation of CP and 4-tBP in Fe(VI) system. The single/double oxygen transfer and single-electron transfer mechanism for the corresponding formation of hydroxylation products and coupling products from CP and 4-tBP were further elucidated by density functional theory (DFT) calculations. Since the cross-coupling reaction was more prone to occur than self-coupling reaction, the addition of another phenol promoted the conversion of the original phenol, leading to the increased kapp values of the two phenols in mixture solution. Finally, the salt bridge experiment also confirmed that the electron transfer between organic pollutants and Fe(VI) was enhanced in mixture solution of phenols. Findings of this study may provide useful information for eliminating co-existing water contaminants by Fe(VI).

Impact of Anode Materials on Electrochemical Degradation of Carbamazepine: A Case Study of Producing the Main By-Product 10,11-Epoxycarbamazepine after Electrochemical Degradation of Carbamazepine

Copper (Cu), nickel (Ni), platinum (Pt), and graphite (G)” have been applied to the electrochemical degradation of carbamazepine (CBZ) from its aqueous solution. The optimum results were observed with graphite anode as follows: fully complete removal of CBZ, 0.0758 min−1 rates constant, and 0.59 Wh/mg consumption energy under these conditions: 5 V, 0.5 g NaCl, and a graphite anode. Kinetics was also considered in the present study, in which rate constants ranged between 0.0023 and 0.0886 min−1. It was observed that applied voltage has an effect on consumption energy giving 0.34, 0.59, and 1.08 Wh/mg using 3, 5, and 7 V, respectively. Field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectroscope (EDS) were used to characterize the organo-metallic precipitates which were formed using Ni and Cu anodes. The main by-product of 10,11-epoxycarbamazepine (EPX-CBZ) was elucidated and monitored using liquid chromatography-time of flight/mass spectrometry (LC-ToF/MS). Therefore, graphite is suggested to be a promising electrode in which it is exhibited good performance compared to other electrodes in terms of removal and consumption of energy.

[To explore mechanism of Scabiosa comosa against liver fibrosis based on pharmacodynamics and network pharmacology].

This study aims to systematically elucidate the pharmacodynamics and network pharmacological mechanism of Mongolian medicinal plants Scabiosa comosa, explore their key targets and related pathways, and further clarify the mechanism of the plants in treating liver fibrosis. Wistar rats were assigned into the blank group, carbon tetrachloride-induced liver fibrosis model group, and low-, medium-, and high-dose S. comosa groups. HE staining and Masson staining were performed for the observation of liver tissue under a microscope. Further, Wistar rats were assigned into a control group and a S. comosa group for administration. Seven days later, blood was collected from the abdominal aorta, and different doses of drug-containing serum samples were used to treat hepatic stellate cell-T6(HSC-T6). Flow cytometry was adopted to detect the apoptosis of HSC-T6 cells. Ultra-high performance liquid chromatography-time of flight-mass spectrometry(UHPLC-TOF-MS) was employed to determine the components in Scabiosa comosa. The target of S. comosa and liver fibrosis were obtained from SwissTargetPrediction and GeneCards, respectively, and the common targets were selected as the anti-liver fibrosis targets. Protein-protein interaction was analyzed via STRING. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment were carried out via Metascape. Phosphatidylinosital 3-kinase(PI3 K), protein kinase B(AKT), p-AKT, p38, and p-p38 targets which are involved in the top-ranked PI3 K/AKT and mitogen activated kinase-like protein(MAPK) signaling pathways were selected for validation via Western blot. The HE and Masson staining results showed that Scabiosa alleviated the hyperplasia of connective tissue and the fibrosis. The serum containing Scabiosa significantly promoted the apoptosis of HSC-T6 in a concentration-dependent manner. A total of 76 chemical components were identified by UHPLC-TOF-MS, among which flavonoids, alkaloids, terpenoids, phenols, and fatty acids were the main components. According to the prediction, there were 63 anti-liver fibrosis targets in Scabiosa comosa, the annotated GO terms of which involved biological processes, cell components, and molecular functions. The KEGG pathway enrichment showed that the targets were mainly involved in PI3 K/AKT, epidermal growth factor receptor(EGFR), RAS-associated protein 1(Rap1), hypoxia-inducible factor 1(HIF-1), resistance to audiogenic seizures(Ras), and MAPK signaling pathways. Western blot results showed that compared with the model group, S. comosa down-regulated the protein levels of α-smooth muscle actin(α-SMA), collagen Ⅰ, PI3 K, AKT, p-AKT, p38, and p-p38 in liver tissue. Compared with the control group, the low-, medium-, and high-dose S. comosa significantly down-regulated the protein levels of α-SMA, collagen Ⅰ, PI3 K, AKT, p-AKT, p38, and p-p38 in HSC-T6. The evidence of pharmacodynamics, network pharmacology, and molecular biology indicated that the plants of S. comosa had significant activity against liver fibrosis, the mechanism of which may involve the regulation of the key targets PI3 K, AKT, and MAPK14 p38 in the PI3 K/AKT and MAPK signaling pathways.

Photodegradation of Decabrominated Diphenyl Ether in Soil Suspensions: Kinetics, Mechanisms and Intermediates

Pollution by polybrominated diphenyl ethers (PBDEs) is a major concern due to their bioaccumulation, persistence, and carcinogenicity. This study aimed to investigate the decabrominated diphenyl ether (BDE-209) photodegradation in soil suspensions. The results indicate BDE-209 can degrade in soil suspensions and its degradation follows pseudo-first-order kinetics. The light sources and intensity effects were studied and the photodegradation rates were 500 W Mercury Lamp &gt; 300 W Mercury Lamp &gt; 500 W Xenon Lamp &gt; 300 W Xenon Lamp, which indicates UV light is the main reason for BDE-209 degradation. Soil particle inhibits BDE-209 photodegradation due to the light-shielding effect. BDE-209 photodegradation rates increased from 0.055 to 0.071 h−1 with pH value increasing from 3.5 to 9.5. This may be because the products are more easily produced in higher pH soil suspensions. The presence of humic acid (HA) may inhibit BDE-209 photodegradation by photo-shielding. Fe3+ and Cu2+ have an adverse effect on BDE-209 photodegradation due to the photo competition. The •OH and 1O2 were detected in soil solutions. Analysis of the photoproducts of BDE-209 by gas chromatography mass spectrometry (GC-MS) and liquid chromatography time of flight mass spectrometry (LC-TOF-MS) showed that BDE-209 was mainly debrominated to the lower-brominated BDEs and the reactive oxygen radicals may not lead to BDE-209 degradation.

Phosphate Solubilizing Microorganism Bacillus sp. MVY-004 and Its Significance for Biomineral Fertilizers' Development in Agrobiotechnology.

Simple SummaryAgriculture is one of the most significant and important sectors globally. Soil fertility and agricultural production are highly dependent on which plant protection and growth promotion substance is used. Although applying mineral fertilizers can promote rapid crop growth, extensive mineral fertilizer use has reduced soil quality worldwide. Such environmental aspects have led to the search for more sustainable methods to provide plants with nutrients, especially phosphorus. Phosphorus is one of the macronutrients that is indispensable for plant development and growth. Phosphate solubilizing microorganisms are widely applied in agronomic practices to increase the productivity of crops while maintaining the health of soils. Nowadays, special attention is focused globally on ecological farming. One of the new technologies in agriculture is the mixing of agricultural bio-stimulants with mineral fertilizers. Agricultural bio-stimulants are bioproducts that contain substances of natural origin along with beneficial microorganisms. They can be used to activate seeds, plants, and soil. Bio-stimulants are used in plants to improve nutritional efficiency, cause changes in vital and structural processes to affect plant growth, enhance abiotic and biotic stress tolerance and increase the yield and quality of products.In this study, a phosphate solubilizing microorganism was isolated from the soil of an agricultural field in Lithuania. Based on 16S rRNA gene sequence analysis, the strain was identified as Bacillus sp. and submitted to the NCBI database, Sector of Applied Bio-catalysis, University Institute of Biotechnology, Vilnius, Lithuania and allocated the accession number KY882273. The Bacillus sp. was assigned with the number MVY-004. The culture nutrient medium and growth conditions were optimized: molasses was used as a carbon source; yeast extract powder was used as an organic source; NH4H2PO4 was used as a nitrogen source; the culture growth temperature was 30 ± 0.5 °C; the initial value of pH was 7.0 ± 0.5; the partial pressure of oxygen (pO2) was 60 ± 2.0; the mixer revolutions per minute (RPM) were 25–850, and the incubation and the fermentation time was 48–50 h. Analysis using Liquid Chromatography Time-of-Flight Mass Spectrometry (LC-TOF/MS) results showed that Bacillus sp. MVY-004 produced organic acids such as citric, succinic, 2-ketogluconic, gluconic, malic, lactic, and oxalic acids. Furthermore, the experiment showed that Bacillus sp. MVY-004 can also produce the following phytohormones: indole-3-acetic (IAA), jasmonic (JA), and gibberellic (GA3) acids. In the climate chamber, the experiment was performed using mineral fertilizer (NPS-12:40:10 80 Kg ha−1) and mineral fertilizers in combination with Bacillus sp. MVY-004 cells (NPS-12:40:10 80 Kg ha−1 + Bacillus sp. MVY-004) in loamy soil. Analysis was performed in three climate conditions: normal (T = 20 °C; relative humidity 60%); hot and dry (T = 30 °C; relative humidity 30%); hot and humid (T = 30 °C; relative humidity 80%).

Phytochemical Analysis, Antioxidant and Bone Anabolic Effects of Blainvillea acmella (L.) Philipson.

Blainvillea acmella (L.) Philipson [Asteraceae] (B. acmella) is an important medicinal plant native to Brazil, and it is widely known as a toothache plant. A plethora of studies have demonstrated the antioxidant activities of B. acmella and few studies on the stimulatory effects on alkaline phosphatase (ALP) secretion from bone cells; however, there is no study on its antioxidant and anabolic activity on bone cells. The study aimed to evaluate the phytochemical contents of aqueous and ethanol extracts of B. acmella using gas chromatography mass spectrometry (GCMS) and liquid chromatography time of flight mass spectrometry (LCTOFMS) along with the total phenolic (TPC) and flavonoid (TFC) contents using Folin-Ciocalteu and aluminum colorimetric methods. The extracts of B. acmella leaves were used to scavenge synthetic-free radicals such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. The bone anabolic effects of B. acmella extracts on MC3T3-E1 cells were measured with 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazoium bromide (MTT) at 1, 3, 5, and 7 days, Sirius-red and ALP at 7 and 14 days, and Alizarin Red S at 14 and 21 days. Comparatively, ethanol extract of B. acmella (BaE) contributed higher antioxidant activities (IC50 of 476.71 µg/ml and 56.01 ± 6.46 mg L-ascorbic acid/g against DPPH and FRAP, respectively). Anabolic activities in bone proliferation, differentiation, and mineralization were also higher in B. acmella of ethanol (BaE) than aqueous (BaA) extracts. Positive correlations were observed between phenolic content (TPC and TFC) to antioxidant (ABTS and FRAP) and anabolic activities. Conversely, negative correlations were present between phenolic content to antioxidant (DPPH) activity. These potential antioxidant and bone anabolic activities in BaE might be due to the phytochemicals confirmed through GCMS and LCTOFMS, revealed that terpenoids of α-cubebene, cryophyllene, cryophyllene oxide, phytol and flavonoids of pinostrobin and apigenin were the compounds contributing to both antioxidant and anabolic effects in BaE. Thus, B. acmella may be a valuable antioxidant and anti-osteoporosis agent. Further study is needed to isolate, characterize and elucidate the underlying mechanisms responsible for the antioxidant and bone anabolic effects.