Hydrogen sulfide alleviates 2,4-dichlorophenol toxicity and promotes its degradation in Phanerochaete chrysosporium

Removal of 1,2-dichloroethane in groundwater using Fenton oxidation

Among the chlorinated aliphatic hydrocarbons, 1,2-dichloroethane (1,2-DCA) is widely used for the synthesis of vinyl chloride monomers. Despite the high demand for 1,2-DCA, it poses a risk to the environment because it is persistent and carcinogenic. Therefore, in this study, several reagents (dithionite, hydrosulfide, sulfite, persulfate, sulfate radicals, and hydroxyl radicals) were evaluated for the degradation of 1,2-DCA. Among these, the hydroxyl radicals generated by the Fenton reaction were the most suitable oxidant, decomposing 92% of 1,2-DCA. Chloride, one of the final oxidized products, was observed, which supported the oxidation reaction. Moreover, with an increasing concentration of hydroxyl radicals, the degradation of 1,2-DCA increased. Furthermore, sufficient amounts of hydrogen peroxide were more important than Fe(II) in the decomposition of 1,2-DCA. The radical reaction can generate larger molecules via the degradation of 1,2-DCA, which are degraded over time. The applicability of Fenton oxidation was evaluated using real 1,2-DCA-contaminated groundwater. Although the degradation of target contaminant was lowered due to the alkaline pH and the presence of chloride and bicarbonate ions in groundwater, the Fenton reaction was still efficient to oxidize 1,2-DCA. These results indicate that Fenton oxidation is an effective technique for the treatment of 1,2-DCA in contaminated groundwater.

Combined application of H2S and a plant growth promoting strain JIL321 regulates photosynthetic efficacy, soil enzyme activity and growth-promotion in rice under salt stress

Salinity stress is one of the most harmful abiotic stresses that inhibit crop growth and grain yield. In this study, a salt-tolerant bacterium was isolated from the soil of the rice rhizosphere and named Myroides sp. JIL321, based on the results of the phylogenetic tree analysis. The strain JIL321 tolerated up to 1, 283.37 mM of NaCl and exhibited positive plant growth-promoting traits, such as the production of indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase. Therefore, the effects of JIL321 on rice (Oryza sativa L.) under salinity stress were determined. The inoculation of strain JIL321 significantly increased the chlorophyll content and the accumulation of osmotic adjustment substances, such as proline and soluble sugars, in rice expose to salt stress. Additionally, strain JIL321 inoculation significantly enhanced the activities of some enzymes commonly found in soil, such as urease, invertase and catalase. Moreover, the production of hydrogen sulfide (H₂S), a pivotal signaling molecule, was also induced in rice by salt stress. Treatment with sodium hydrogen sulfide (NaHS, H₂S donor) improved salt stress tolerance of the rice, while treatment with hypotaurine (HT, H₂S scavenger) significantly suppressed it. Interestingly, NaHS treatment also improved the production of IAA and ACC deaminase in strain JIL321 under 0 mM and 150 mM salt concentrations. The combined treatment of JIL321 and NaHS could further improve the growth of salt-stressed rice seedlings, most likely due to the interaction effect between H₂S and strain JIL321. To our knowledge, this study is the first to demonstrate that the combined use of H₂S and plant growth-promoting bacteria could alleviate the adverse effects of salt stress on rice plants, and further verifies the novel role of H₂S as a signaling molecule that enhance the tolerance of plant to abiotic stresses.

Biodegradation and detoxification of neonicotinoid insecticide thiamethoxam by white-rot fungus Phanerochaete chrysosporium

The extensive use of neonicotinoid pesticides in the past two decades caused serious impacts on many kinds of living beings. Therefore, it has been strongly suggested to detoxify and eliminate neonicotinoids' residual levels in environment. Here, the degradation and detoxification of thiamethoxam (THX) by white-rot fungus Phanerochaete chrysosporium was conducted. Results shown that P. chrysosporium can tolerate THX and degraded 49% of THX after incubation for 15 days, and then 98% for 25 days at the initial concentration of 10 mg/L, which indicates the excellent degradation ability of this fungus to THX. Based on the by-products identified, THX underwent dechlorination, nitrate reduction, and C-N cleavage between the 2-chlorothiazole ring and oxadiazine. (Z)-N-(3-methyl-1,3,5-oxadiazinan-4-ylidene)nitramide and 3-methyl-1,3,5-oxadiazinan-4-imine were identified as the main metabolites. The impacts of THX and its corresponding degradation intermediates on the growth of E. coil and Microcystis aeruginosa as well as the germination of rape and cabbage demonstrated that P. chrysosporium effectively degrades THX into metabolites and reduces its biotoxicity. The present work demonstrates that P. chrysosporium can be effectively used for degradation and detoxification of THX.

Hydrogen sulfide and calcium effects on cadmium removal and resistance in the white-rot fungus Phanerochaete chrysosporium

Hydrogen sulfide (H₂S), an emerging gas transmitter, has been shown to be involved in multiple intracellular physiological and biochemical processes. In this study, the effects of hydrogen sulfide coupled with calcium on cadmium removal and resistance in Phanerochaete chrysosporium were examined. The results revealed that H₂S enhanced the uptake of calcium by P. chrysosporium to resist cadmium stress. The removal and accumulation of cadmium by the mycelium was reduced by H₂S and Ca²⁺ pretreatment. Moreover, oxidative damage and membrane integrity were alleviated by H₂S and Ca²⁺. Corresponding antioxidative enzyme activities and glutathione were also found to positively respond to H₂S and Ca²⁺, which played an important role in the resistance to cadmium-induced oxidative stress. The effects of hydroxylamine (HA; a hydrogen sulfide inhibitor) and ethylene glycol-bis-(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA; a calcium chelator) toward H₂S and Ca²⁺ and their cross-interactions confirmed the positive roles and the potential crosstalk of H₂S and Ca²⁺ in cadmium stress resistance. These findings imply that the protective effects of H₂S in P. chrysosporium under cadmium stress may occur through a reduction in the accumulation of cadmium and promotion of the antioxidant system, and the H₂S-regulated pathway may be associated with the intracellular calcium signaling system.Key points• Altered monoterpenoid tolerance mainly related to altered activity of efflux pumps.• Increased tolerance to geranic acid surprisingly caused by decreased export activity.• Reduction of export activity can be beneficial for biotechnological conversions.

A comprehensive insight into the application of white rot fungi and their lignocellulolytic enzymes in the removal of organic pollutants

Environmental problems resultant from organic pollutants are a major current challenge for modern societies. White rot fungi (WRF) are well known for their extensive organic compound degradation abilities. The unique oxidative and extracellular ligninolytic systems of WRF that exhibit low substrate specificity, enable them to display a considerable ability to transform or degrade different environmental contaminants. In recent decades, WRF and their ligninolytic enzymes have been widely applied in the removal of polycyclic aromatic hydrocarbons (PAHs), pharmaceutically active compounds (PhACs), endocrine disruptor compounds (EDCs), pesticides, synthetic dyes, and other environmental pollutants, wherein promising results have been achieved. This review focuses on advances in WRF-based bioremediation of organic pollutants over the last 10 years. We comprehensively document the application of WRF and their lignocellulolytic enzymes for removing organic pollutants. Moreover, potential problems and intriguing observations that are worthy of additional research attention are highlighted. Lastly, we discuss trends in WRF-remediation system development and avenues that should be considered to advance research in the field.

A novel MnOOH coated nylon membrane for efficient removal of 2,4-dichlorophenol through peroxymonosulfate activation

2,4-Dichlorophenol (2,4-DCP) is a highly toxic water contaminant. In this study, we demonstrate a novel catalytic filtration membrane by coating MnOOH nanoparticles on nylon membrane (MnOOH@nylon) for improved removal of 2,4-DCP through a synergetic "trap-and-zap" process. In this hybrid membrane, the underlying nylon membrane provides high adsorption affinity for 2,4-DCP. While the immobilized MnOOH nanoparticles on the membrane surface provide catalytic property for peroxymonosulfate activation to produce reactive oxygen species (ROS), which migrate with the fluid to the underlying nylon membrane pore channels and react with the adsorbed 2,4-DCP with a much higher rate (0.9575 mg L^-1 min^-1) than that in the suspended MnOOH particle system (0.1493 mg L^-1 min^-1). The forced flow in the small voids of the MnOOH nanoparticle coating layer (< 200 nm) and channels of nylon membrane (~220 nm) is critical to improve the 2,4-DCP adsorption, ROS production, and 2,4-DCP degradation. The hybrid MnOOH@nylon membrane also improves the stability of the MnOOH nanoparticles and the resistibility to competitive anions, due to much higher concentration ratio of the adsorbed 2,4-DCP and produced ROS versus background competitive ions in the membrane phase. This study provides a generally applicable approach to achieve high removal of target contaminants in catalytic membrane processes.

Study on the oxidative stress and transcriptional level in Cr(VI) and Hg(II) reducing strain Acinetobacter indicus yy-1 isolated from chromium-contaminated soil

The bioreduction of Cr(VI) and Hg(II) has become a hot topic in the field of heavy metals bioremediation. However, the mechanism of antioxidant stress in Cr(VI) and Hg(II) reducing bacteria is still not clear. In this work, a novel Cr(VI) and Hg(II) reducing strain Acinetobacter indicus yy-1, was isolated from chromium landfill at a chromate factory, which was used to investigate the mechanism of antioxidant stress during the Cr(VI) and Hg(II) reduction process. The results demonstrated that the removal of Cr(VI) and Hg(II) by A. indicus yy-1 from solution was through reduction rather than biosorption. The reduction rates of Cr(VI) and Hg(II) by resting cells reached 59.71% and 31.73% at 24 h with initial concentration of 10 mg L^-1, respectively. X-ray photoelectron spectroscopy (XPS) analysis further showed that Cr(III) and Hg(0) were mainly the Cr(VI)- and Hg(II)-reduced productions, respectively. Results of physiological assays showed Hg(II) was more toxic to A. indicus yy-1 than Cr(VI), and the activities of antioxidant enzymes (SOD and CAT) were significantly increased in A. indicus yy-1 for relieving the oxidative stress. The transcriptional level of genes related to Cr(VI) and Hg(II) reductases and antioxidant enzymes were up-regulated, indicating that the reductases have participated in the reduction of Cr(VI) and Hg(II), and SOD and CAT served as the vital antioxidant enzymes for defending the oxidative stress. This work provides a deep insight into the mechanism of antioxidant stress in Cr(VI) and Hg(II) reducing bacteria, which helps seek the highly resistant heavy metal reducing bacteria.

Bio-photoelectrochemcial system constructed with BiVO4/RGO photocathode for 2,4-dichlorophenol degradation: BiVO4/RGO optimization, degradation performance and mechanism

A single-chamber bio-photoelectrochemical system (BPES) constructed with BiVO₄/reduced graphene oxide (RGO) photocathode was proposed for 2,4-dichlorophenol (2,4-DCP) degradation under simulated solar irradiation. The BiVO₄/RGO (B/G) composites were synthesized, optimized and characterized by various techniques to analyze their physico-chemical and photocatalytic properties. Results showed that B/G (5 wt% - 9 h - 150 °C) exhibited the best photocatalytic activity for 2,4-DCP degradation, which was 1.5 times of that of BiVO₄, due to its better light absorption, faster electrons transfer, and more efficient photo-generated e^- - h⁺ separation. Reactive species trapping experiments revealed that ·OH was the main radical leading to 2,4-DCP degradation, and h⁺ also influenced 2,4-DCP removal. The 2,4-DCP (20 mg/L) removal rate and current output from the illuminated BPES were much higher than those of the unilluminated reactor (68.5 % vs. 41.8 %, 60.31 A/m³ vs. 40.07 A/m³) in 24 h, and the cathode potential was more negative, indicating that photocathode catalytic process was favorable to pollutants degradation and energy generation. Intermediates of 2,4-DCP degradation in the BPES were identified, and accordingly, possible degradation pathway and mechanism were proposed. This research advanced the development of efficient photocathode and mechanism of recalcitrant wastewater treatment in the BPES.

Alleviating the toxicity of quantum dots to Phanerochaete chrysosporium by sodium hydrosulfide and cysteine

Quantum dots (QDs) have caused large challenges in clinical tests and biomedical applications due to their potential toxicity from nanosize effects and heavy metal components. In this study, the physiological responses of Phanerochaete chrysosporium (P. chrysosporium) to CdSe/ZnS QDs with either an inorganic sulfide NaHS or an organic sulfide cysteine as antidote have been investigated. Scanning electron microscope analysis showed that the hyphal structure and morphology of P. chrysosporium have obviously changed after exposure to 100 nM of COOH CdSe/ZnS 505, NH₂ CdSe/ZnS 505, NH₂ CdSe/ZnS 565, or NH₂ CdSe/ZnS 625. Fourier transform infrared spectroscopy analysis indicated that the existence of hydroxyl, amino, and carboxyl groups on cell surface could possibly conduct the stabilization of QDs in an aqueous medium. However, after NaHS or cysteine treatment, the cell viability of P. chrysosporium exposed to CdSe/ZnS QDs increased as compared to control group, since NaHS and cysteine have assisted P. chrysosporium to alleviate oxidative damage by regulating lipid peroxidation and superoxide production. Meanwhile, NaHS and cysteine have also stimulated P. chrysosporium to produce more antioxidant enzymes (superoxide dismutase and catalase), which played significant roles in the defense system. In addition, NaHS and cysteine were used by P. chrysosporium as sulfide sources to promote the glutathione biosynthesis to relieve CdSe/ZnS QDs-induced oxidative stress. This work revealed that sulfide sources (NaHS and cysteine) exerted a strong positive effect in P. chrysosporium against the toxicity induced by CdSe/ZnS QDs.

Sulfadiazine biodegradation by Phanerochaete chrysosporium: Mechanism and degradation product identification

Antibiotic contaminants have become a severe environmental problem in recent years and finding effective ways to deal with this issue is of great importance. In this study, Phanerochaete chrysosporium was used to degrade sulfadiazine (SDZ), which is frequently detected in the culture medium of isolates from soil and surface water systems. The results demonstrate that 10 mg L^-1 SDZ can be completely degraded by P. chrysosporium under conditions of pH 5.7 and 30 °C within 6 days. The Q-Exactive-MS/MS analysis identified and confirmed several different SDZ degradation intermediates, and four proposed degradation pathways of SDZ were deduced. Moreover, enzyme activity tests revealed that manganese peroxidase and ligninolytic peroxidase played important roles in SDZ degradation. Moreover, a transcriptome analysis method was performed to explore the mechanism and pathways of SDZ degradation by P. chrysosporium in greater detail. The results of GO and KEGG analysis strongly suggest that the metabolism pathway is significantly activated and plays an important role in antibiotic degradation. Further, this is the first study to identify SDZ degradation intermediates and two main intermediates were found to be involved in possible SDZ degradation pathways. This study is also the first report results from RNA sequencing to evaluate genome-wide changes of P. chrysosporium to further explore SDZ degradation mechanism.

Heterogeneous Oxidation of Phenolic Compounds with Photosensitizing Catalysts Incorporated into Chitosan

The increasing amount of hazardous micropollutants in the aqueous environment has recently become a concern, especially because they are not usually included in environmental monitoring programs. There is also limited knowledge regarding their behavior in the environment and their toxicity. This paper presents results regarding the heterogeneous photosensitized oxidation of 10 phenolic compounds under visible light. All of the selected compounds are classified as pollutants of emerging concern. For the first time, the application of photosensitizing catalysts incorporated into a chitosan carrier was investigated from several points of view, namely, structure characterization, singlet oxygen generation potential, photodegradation ability, biodegradability, and toxicity assessment. It was found that compounds of different origins were degraded with high effectivity. Photoactive chitosan was stable and could be reused for at least 12 cycles without losing its photocatalytic activity. The Hammett constants for all of the degraded compounds were determined. Improved biodegradability after the treatment was achieved for almost all compounds, apart from 4-hydroxybenzoic acid, and only slightly for 2-phenylphenol. The acute toxicity was assessed using bioluminescent Vibrio fischeri bacteria, indicating lower toxicity than the parent compounds.

Alleviation of heavy metal and silver nanoparticle toxicity and enhancement of their removal by hydrogen sulfide in Phanerochaete chrysosporium

Hydrogen sulfide (H₂S), an important cellular signaling molecule, plays vital roles in mediating responses to biotic/abiotic stresses. Influences of H₂S on metal removal, cell viability, and antioxidant response of Phanerochaete chrysosporium upon exposure to heavy metals and silver nanoparticles (AgNPs) in the present study were investigated. An enhancement in Pb(ΙΙ) removal with an increase in concentration of the H₂S donor sodium hydrosulfide (NaHS) was observed, and the maximum removal efficiencies increased by 31% and 17% under 100 and 200 mg/L Pb(ΙΙ) exposure, respectively, in the presence of 500 μM NaHS. Application of 500 μM NaHS increased the cell viability by 15%-39% under Pb(II) stress (10-200 mg/L) with relative to the untreated control. Increase in total Ag uptake and cell survival was also elicited by NaHS in a concentration-dependent manner under AgNP stress. Meanwhile, activities of superoxide dismutase and catalase were significantly enhanced with the introduction of NaHS under stresses of Pb(II), Cd(II), Cu(II), Zn(II), Ni(II), and AgNPs. The inhibition in lipid peroxidation and oxidative stress was observed in P. chrysosporium cells exposed to these toxicants following NaHS pretreatment, which could be attributed to the upregulation in antioxidant enzymes. The results obtained suggest that H₂S can alleviate heavy metals and AgNP-induced toxicity to P. chrysosporium and improve the removal efficiency of these toxicants from wastewater.

Potentiality of white-rot fungi in biosorption of nickel and cadmium: Modeling optimization and kinetics study

The present study aimed to analyze simultaneous biosorption of Cd⁺² and Ni⁺² by living Phanerochaete chrysosporium as low-cost and eco-friendly biosorbent following optimization by applying a central composite design. The effect of operating parameters such as solution pH (4.0-8.0), temperature (20-40 °C), contact time (3-15 h), initial Cd⁺² and Ni⁺² concentrations (15-35, 5-25 mg L^-1, respectively) was evaluated by response surface methodology (RSM) for optimizing biosorption process. The Cd⁺² and Ni⁺² ions at 25 and 16 mg L^-1 were accumulated in P. chrysosporium with the efficiency of 96.23% and 89.48%, respectively, at pH of 6 and 36 °C after around 9 h under well mixing. The equilibrium data were fitted well with Langmuir isotherm model with maximum biosorption capacity of 71.43 and 46.50 mg g^-1 for Cd⁺² and Ni⁺², respectively. In addition, the pseudo-second order kinetic model could describe the kinetic data adequately. Further, possible interaction pathway among metals and P. chrysosporium functional groups were studied by Fourier transform infrared (FT-IR) spectroscopy. Furthermore, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) techniques were applied for morphology investigation and semi elemental analysis.

Synthesis of N-doped ZnO nanoparticles with cabbage morphology as a catalyst for the efficient photocatalytic degradation of methylene blue under UV and visible light

In this study, the synthesis of nitrogen-doped zinc oxide nanoparticles with a cabbage like morphology (N-ZnONCBs) by a hydrothermal method using zinc acetate dihydrate as a precursor and hydrazine monohydrate as a nitrogen source is reported. N-ZnONCB were characterized using UV-visible Spectroscopy (UV-Vis), Fluorescence Spectroscopy, Fourier Transmittance Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Raman Spectroscopy, Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Electron Dispersive Spectroscopy (EDS) and EDX elemental mapping. N-ZnONCBs were tested for their photocatalytic capabilities in the degradation of methylene blue (MB) under UV-light and visible light irradiation for about 0 to 80 minutes and 0 to 50 min respectively. The N-ZnONCB catalyst demonstrated improved photodegradation efficiency (98.6% and 96.2%) and kinetic degradation rates of MB (k = −0.0579 min⁻¹ and k = −0.0585 min⁻¹) under UV light and visible light irradiation at different time intervals. The photodegradation study was also evaluated with different dosages of N-ZnONCB catalyst, different initial concentrations of MB and variation in the pH (3, 5, 9 and 11) of the solution of MB under UV light and visible light irradiation. The photocatalytic degradation intermediate products were obtained by liquid chromatography mass spectra (LC-MS) and also complete mineralization was determined by using Total Organic Carbon (TOC) studies. This photocatalyst was also tested with 2,4-dichlorophenol (2,4-DCP) under visible light irradiation at different time intervals. Fluorescence and quenching studies were performed for the binding interaction between the N-ZnONCB catalyst and MB dye. A Zetasizer was used to find the charge and average size of the N-ZnONCB catalyst and also the charge of the N-ZnONCB catalyst before and after MB dye solution adsorption. The N-ZnONCB catalyst was also tested for its photostability and reusability with a percentage degradation rate of MB (93.2%) after 4 cycle experiments. These results have clearly demonstrated that the N-ZnONCB catalyst can be applied for the photocatalytic degradation of MB from wastewater samples.

In this study, the synthesis of nitrogen-doped zinc oxide nanoparticles with a cabbage like morphology (N-ZnONCBs) by a hydrothermal method using zinc acetate dihydrate as a precursor and hydrazine monohydrate as a nitrogen source is reported.

Effects of cadmium on calcium homeostasis in the white-rot fungus Phanerochaete chrysosporium

Due to the widespread application of white-rot fungi for the treatment of pollutants, it's crucial to exploit the special effects of pollutants on the microbes. Here, we studied the effects of cadmium on calcium homeostasis in the most studied white-rot fungus Phanerochaete chrysosporium. The response of P. chrysosporium to cadmium stress is concentration-dependent. A high concentration of cadmium caused the release of calcium from P. chrysosporium, while a hormesis effect was observed at a lower cadmium concentration (10 μM), which resulted in a significant increase in calcium uptake and reversed the decrease in cell viability. Calcium (50 μM) promoted cell viability (127.2% of control), which reflects that calcium can protect P. chrysosporium from environmental stress. Real-time changes in the Ca²⁺ and Cd²⁺ fluxes of P. chrysosporium were quantified using the noninvasive microtest technique. Ca²⁺ influx decreased significantly under cadmium exposure, and the Ca²⁺ channel was involved in Ca²⁺ and Cd²⁺ influx. The cadmium and/or calcium uptake results coupled with the real-time Ca²⁺ and Cd²⁺ influxes microscale signatures can enhance our knowledge of the homeostasis of P. chrysosporium with respect to cadmium stress, which may provide useful information for improving the bioremediation process.

Cagelike mesoporous silica encapsulated with microcapsules for immobilized laccase and 2, 4-DCP degradation

In this study, cage-like mesoporous silica was used as the carrier to immobilize laccase by a physical approach, followed by encapsulating with chitosan/alginate microcapsule membranes to form microcapsules of immobilized laccase based on layer-by-layer technology. The relationship between laccase activity recovery/leakage rate and the coating thickness was simultaneously investigated. Because the microcapsule layers have a substantial network of pores, they act as semipermeable membranes, while the laccase immobilized inside the microcapsules acts as a processing plant for degradation of 2,4-dichlorophenol. The microcapsules of immobilized laccase were able to degrade 2,4-dichlorophenol within a wide range of 2,4-dichlorophenol concentration, temperature and pH, with mean degradation rate around 62%. Under the optimal conditions, the thermal stability and reusability of immobilized laccase were shown to be improved significantly, as the removal rate and degradation rate remained over 40.2% and 33.8% respectively after 6cycles of operation. Using mass spectrometry (MS) and nuclear magnetic resonance (NMR), diisobutyl phthalate and dibutyl phthalate were identified as the products of 2,4-dichlorophenol degradation by the microcapsules of immobilized laccase and laccase immobilized by a physical approach, respectively, further demonstrating the degradation mechanism of 2,4-dichlorophenol by microcapsule-immobilized laccase.

Endogenous and Exogenous Calcium Involved in the Betulin Production from Submerged Culture of Phellinus linteus Induced by Hydrogen Sulfide

Using pharmacological and biochemical approaches, Ca(2+) involved in the betulin production in mycelia of Phellinus linteus induced by hydrogen sulfide (H2S) were investigated. The results showed that 2 mM H2S donor NaHS or 10 mM CaCl2 was found to enhance the betulin content in the mycelia of Phellinus to the maximum, which were 112.43 and 93.24% higher than that in the control, respectively. Further, NaHS and CaCl2 co-treatment also showed positive outcome, which were 128.95 or 24.52% higher than that in the control or NaHS treatment. At the same time, NaHS also enhanced the content of Ca(2+) and CaM. But, the above positive inductive effects for Ca(2+), CaM, and betulin production can be blocked with either Ca(2+) channel blocker (LaCl3, 2-aminoethoxydiphenyl borate) or Ca(2+) chelator (ethylenediaminetetraacetic acid (EDTA)). Among of them, betulin content was reduced 35.06% by NaHS and EGTA to the minimum, and this reduction could be reversed by the application of CaCl2 (NaHS + EGTA + CaCl2). From above results, it can be concluded that endogenous and exogenous calcium involved in the betulin production from submerged culture of P. linteus induced by hydrogen sulfide.

Integral cross sections for electron impact excitation of vibrational and electronic states in phenol

We report on measurements of integral cross sections (ICSs) for electron impact excitation of a series of composite vibrational modes and electronic-states in phenol, where the energy range of those experiments was 15-250 eV. There are currently no other results against which we can directly compare those measured data. We also report results from our independent atom model with screened additivity rule correction computations, namely, for the inelastic ICS (all discrete electronic states and neutral dissociation) and the total ionisation ICS. In addition, for the relevant dipole-allowed excited electronic states, we also report f-scaled Born-level and energy-corrected and f-scaled Born-level (BEf-scaled) ICS. Where possible, our measured and calculated ICSs are compared against one another with the general level of accord between them being satisfactory to within the measurement uncertainties.

Magnetic CuO@Fe3O4 nanocomposite as a highly active heterogeneous catalyst of persulfate for 2,4-dichlorophenol degradation in aqueous solution

Fe₃O₄@CuO nanocomposite was fabricated through a novel impregnation method. Both sulfate radicals and hydroxyl radicals can be produced effectively in the activated persulfate system by the composite to degrade the 2,4-dichlorophenol.

Degradation of 2,4-dichlorophenol in wastewater by low temperature plasma coupled with TiO2 photocatalysis

The degradation pathway of 2,4-DCP was deduced by reference to similar studies of other scholars and mass spectrometry analysis.