OH Free Radicals Research Articles

Numerical Study on the Explosion Reaction Mechanism of Multicomponent Combustible Gas in Coal Mines

Combustible gases, such as CO, CH4, and H2, are produced during spontaneous coal combustion in goaf, which may cause an explosion under the stimulation of an external fire source. It is of great significance to study the influence of combustible gases, such as CO and H2, on the characteristics of a gas explosion. In this study, CHEMKIN software (Version 17.0) and the GRI-Mech 3.0 reaction mechanism were used to study the influences of different concentration ratios between CO and H2 on the ignition delay time, free radical concentration, and key reaction step of a gas explosion. The results show that the increase in the initial CH4 and CO concentrations prolonged the ignition delay time, while the increase in the H2 concentration shortened the time and accelerated the explosion reaction. The addition of H2 promoted the generation of free radicals (H⸱, O⸱, ⸱OH) and accelerated the occurrence of the gas explosion. CO generated ⸱OH free radicals and dominated the methane consumption through the R119 and R156 reactions. As the concentrations of CO and H2 increased, the R38 reaction gradually became the main driving factor of the gas explosion.

Microscopic mechanistic study of the penetration distributions for plasma reactive oxygen and nitrogen species based on sialic acid targeting on the cell membrane surface

The ability of cold atmospheric plasmas (CAPs) to produce a wide range of active constituents while maintaining a low or even room temperature of the gas has made it a novel research area of great interest. During plasma action, cancer cell membrane surface components are susceptible to oxidative modification by reactive oxygen and nitrogen species (RONS). In this study, the process of oxidative modification of membrane surface components sialic acid by RONS was investigated based on molecular dynamics simulations, and the penetration mechanism of long-lived particles ONOOH and its homolytic products at the membrane-water interface and the effect of appropriate electric field action were studied. The results showed that cancer cells with high sialic acid expression were less stable than healthy cells. Plasma treatment may promote the ONOOH homolysis process, and its homolysis product OH free radical is more likely to adsorb near sialic acid molecules by hydrogen bonding, resulting in oxidative modification. The interaction force between OH free radical and sialic acid molecules is stronger than ONOOH, which helps to further understand the oxidative modification reaction in membrane environment. At the same time, appropriate electric field stimulation can enhance the depth of penetration of RONS to more effectively treat the pathological state of biological tissues. The study proposes the use of membrane surface sialic acid as a cancer therapeutic target and provides guidance for improving the depth of RONS penetration and maximizing the survival of healthy cells, which contributes to the further clinical translation of plasma biomedicine.

Nanostructured bi-metallic biochar: An innovative approach for arsenic (III) removal from contaminated water

Possessing variable valence states, the element Arsenic (As) is intimidating the quality of the ecology and human health severely. In this study, eliminating As (III) from water-based solutions with great efficiency was done using Bagasse-Mn-Al, a sugarcane bagasse-derived biochar impregnated with Mn and Al. The Bagasse-Mn-Al composite yielded higher removal efficiency towards As (III) than the biochar itself. About 89.53 % of As (III) was removed within 65 min maintaining the very first concentration of As (III) at 400 μg/L, initial pH at 2–2.5, and adsorbent dosage at 0.625 g/L. The Bagasse-Mn-Al composite showed an adsorption potential maximum of 54.945 mg/g which is superior to most of the cheaply synthesized metal-impregnated biochar reported. Results from a variety of characterization techniques indicated that the •OH free radical in the Bagasse-Mn-Al composite mainly contributed to the removal of As (III) where oxidation and complexation were the major mechanisms. With high catalytic efficiency, this cost effectively produced metal-coated biochar showed easy and effective separation of As (III) from aqueous solution. Further, this study focuses on the high potential of Bagasse-Mn-Al adsorbent in the treatment of both ground and wastewater.

In-situ manganese-aluminum-iron biochar derived from waste flocs for enhanced peroxymonosulfate oxidation: Role of Fe/Mn drives active species based on aluminum adsorption and synergistic promoted electron transfer

Conventional coagulation or enhanced coagulation water treatment produced mass floc sludge, which contained plenty of metals and organic matter. Floc sludge disposal and resource recycling was vital relevance and urgently needed. Here, we reported on the waste flocs recycling through in-situ manganese-aluminum-iron biochar (MAFBC) synthesized via one-step pyrolysis using potassium permanganate (KMnO4) oxidation- aluminum-iron composite flocculant coagulation for humic acid removal floc sludge as raw material. Compared with ex-situ loaded or similar types of biochar, MAFBC showed faster and efficient activation effect of peroxymonosulfate (PMS) to degrade tetracycline (TC). TC was rapidly removed within 1 min in MAFBC/PMS system with degradation rate constant Kobs was 1.825 min−1, which mainly attributed to the multiple promoting effects of manganese-aluminum-iron. Aluminum oxides facilitated TC adsorption and synergistic Fe/Mn further significantly promoted electron transfer on the surface of the MAFBC. Additionally, bimetallic structure of Fe/Mn and the CO functional group on MAFBC accelerated the formation of reactive species. The redox cycles of Fe2+/Fe3+ and Mn2+/Mn3+/Mn4+ promoted the formation of free radicals OH and SO4−. Moreover, O2– and 1O2 also assumed an important role for TC removal during active species evolution drived by Fe/Mn. This research provides a new perspective for in-situ design of economical and stable metal carbon-based water treatment activator, and make contributions to the utilization of waste flocs in water treatment.

EFFECT OF ADDING N2/H2O TO ETHYLENE LAMINAR DIFFUSION FLAME ON SOOT FORMATION

Abstract The method of adding exhaust gas to fuel to reduce soot and NOX is called Exhaust Gas Recirculation (EGR). This paper was carried out to investigate the effect of adding N2 and H2O to the fuel side to dilute ethylene on soot generation in laminar diffusion flame by combining experiment and numerical simulation. In the experiment, the flame was optically detected, and the volume fraction of soot and temperature was reconstructed. The numerical simulation adopts a simplified GRI-Mech 3.0 ethylene 23-step combustion reaction mechanism. It introduces virtual species FX (F1H2O, F2H2O, F3H2O) to isolate the effects of H2O addition on thermal, transport, chemical, and density effects. The results show that the numerical values agree well with the experimental results. At the same dilution ratio, the direct involvement of H2O in the reaction affects the flame temperature and intermediate products, leading to a more significant suppressing effect on soot than N2 dilution. After decoupling the effects of H2O, it was found that there are two main reasons for the decrease of soot caused by the addition of H2O. The first is the dilution effect and thermal effect, which hinder the HACA reaction by reducing the concentration of intermediate component C2H2, greatly inhibiting the surface growth rate of soot, and playing a decisive role in reducing the formation of soot. The second is the chemical effect, which mainly enhances the oxidation process of soot by increasing the concentration of OH free radicals during combustion through the elementary reaction OH+H2↔H+H2O. Additionally, the degree of influence of various effects on soot was qualitatively determined as follows: dilution effect > chemical effect > thermal effect > density effect > transport effect.

Construction of Z-scheme SbVO4/g-C3N4 heterojunction with efficient photocatalytic degradation performance

As visible light responsive materials, g-C3N4 has become an outstanding research object for photocatalysis due to its facile synthesis, excellent chemical and thermal stability. In this paper, a Z-scheme SbVO4/g-C3N4 heterojunction was successfully constructed by thermal polymerization method. The synthesized SbVO4/g-C3N4 nanocomposite showed efficient photocatalytic activity on tetracycline (TC) degradation. The photocatalytic degradation of TC follows a first-order kinetic model, in which ·O2− and ·OH free radicals play a major role. The formation of Z-scheme heterojunction between SbVO4 and g-C3N4 can effectively promote the separation of photogenerated electron-hole pairs and the generation of ·O2− and ·OH. The photocatalytic removal rate of TC reached 82.3 % within 150 min under visible light. The as-synthesized SbVO4/g-C3N4 heterojunction can still maintain good stability. Furthermore, a photocatalytic degradation mechanism for the SbVO4/g-C3N4 heterojunction is proposed.

Green and efficient extraction of polyphenols from the leaves of Quercus dentata Thunb and in vitro antioxidant activities of polyphenol extract

The ultrasonic-coupled deep eutectic solvents method was firstly applied to extract phenolic compounds efficiently from the leaves of Quercus dentata Thunb. Five factors including type of deep eutectic solvent, water content, solid-liquid ratio, extraction time and extraction temperature were investigated based on total polyphenol content. The optimal extraction parameters were obtained through response surface methodology, that is, the deep eutectic solvent was composed of choline chloride and 1, 4-butanediol (molar ratio 1:2) with water content of 38%, the solid-liquid ratio was 1:30 g/mL, the extraction time was 31 min, the extraction temperature was 55 °C. At this condition, total polyphenol content reached the highest value of 78.56 ± 2.44 mg gallic acid/g. In addition, eleven phenolic compounds were identified by high performance liquid chromatography quadrupole/time-of flight mass spectrometry as flavonol glycosides. And then, the extraction showed good antioxidant activities in reducing transition metals (Fe3+, Cu2+, Mo6+) and scavenging free radicals (DPPH·, ABTS+·, O2−· and ·OH). Among them, the IC50 values of scavenging DPPH·, ABTS+·, O2−· and ·OH free radicals were 10.87 ± 0.25 μg mL−1, 8.04 ± 0.24 μg/mL, 149.47 ± 5.27 μg/mL and 131.73 ± 5.31 μg/mL, respectively. On the other hand, the extraction at the cellular level exerted its protective effect on PC12 cells by increasing the cell survival rate of H2O2-induced damaged cells, weakening the level of reactive oxygen species in damaged cells. Overall, this study provided a green and high-efficient strategy for extracting phenolic compounds with great antioxidant activities from Q. dentata leaves.

Preparation and Application of a Novel S-Scheme Nanoheterojunction Photocatalyst (LaNi0.6Fe0.4O3/g-C3N4).

Rapid recombination of photogenerated electrons and holes affects the performance of a semiconductor device and limits the efficiency of photocatalytic water splitting for hydrogen production. The use of an S-scheme nanoscale heterojunction catalyst for the separation of photogenerated charge carriers is a feasible approach to achieve high-efficiency photocatalytic hydrogen evolution. Therefore, we synthesized a three-dimensional S-scheme nanoscale heterojunction catalyst (LaNi0.6Fe0.4O3/g-C3N4) and investigated its activity in photocatalytic water splitting. An analysis of the band structure (XPS, UPS, and Mott-Schottky) indicated effective interfacial charge transfer in an S-scheme nanoscale heterojunction composed of two n-type semiconductors. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) spectroscopy confirmed that the light-induced charge transfer followed the S-scheme mechanism. Based on the capture test (EPR) of •OH free radicals, it can be seen that the enhanced activity is attributed to the S-scheme carrier migration mechanism in heterojunction, which promotes the rapid adsorption of H+ by the abundant amino sites in g-C3N4, thus effectively generating H2. The 2D/2D LaNi0.6Fe0.4O3/g-C3N4 heterojunction has a good interface and produces a built-in electric field, improving the separation of e- and h+ while increasing the oxygen vacancy. The synergistic effect of the heterostructure and oxygen vacancy makes the photocatalyst significantly better than LaNi0.6Fe0.4O3 and g-C3N4 in visible light. The hydrogen evolution rate of the composite catalyst (LaNi0.6Fe0.4O3/g-C3N4-70 wt %) was 34.50 mmol·h-1·g-1, which was 40.6 times and 9.2 times higher than that of the catalysts (LaNiO3 and g-C3N4), respectively. After 25 h of cyclic testing, the catalyst (LaNi0.6Fe0.4O3/g-C3N4-70 wt %) composite material still exhibited excellent hydrogen evolution performance and photostability. It was confirmed that the synergistic effect between abundant active sites, enriched oxygen vacancies, and 2D/2D heterojunctions improved the photoinduced carrier separation and the light absorption efficiency of visible light. This study opens up new possibilities for the logical design of efficient photodecomposition using 2D/2D heterojunctions combined with oxygen vacancies.

Optimization of Flavonoid Extraction from Abelmoschus manihot Flowers Using Ultrasonic Techniques: Predictive Modeling through Response Surface Methodology and Deep Neural Network and Biological Activity Assessment.

Understanding the optimal extraction methods for flavonoids from Abelmoschus manihot flowers (AMF) is crucial for unlocking their potential benefits. This study aimed to optimize the efficiency of flavonoid extraction from AMF. After comparing extraction methods, the ultrasonic cell crusher demonstrated superior performance over conventional techniques. Four key factors-solid-to-liquid ratio (1:10 to 1:50 g·mL-1), ethanol concentration (55% to 95%), ultrasonic time (10 to 50 min), and ultrasonic power (5% to 25% of 900 W)-were investigated and normalized using the entropy weight method. This led to a comprehensive evaluation (CE). Optimization of extraction conditions for the ultrasonic cell crusher was achieved through response surface methodology and a deep neural network model, resulting in optimal parameters: ethanol volume fraction of 66%, solid-to-liquid ratio of 1:21 g/mL, extraction efficiency of 9%, and extraction duration of 35 min, yielding a CE value of 23.14 (RSD < 1%). Additionally, the inhibitory effects of the optimized extracts against Streptococcus mutans (S. mutans) were assessed. The results revealed that AMF extract (AMFE) exhibits inhibitory effects on S. mutans, with concomitant inhibition of sucrase and lactate dehydrogenase (LDH). The MIC of AMFE against planktonic S. mutans is 3 mg/mL, with an MBC of 6 mg/mL. Within the concentration range of 1/8 MIC to 2 MIC of AMFE, the activities of sucrase and LDH decreased by 318.934 U/mg prot and 61.844 U/mg prot, respectively. The antioxidant activity of AMFE was assessed using the potassium ferricyanide reduction and phosphomolybdenum methods. Additionally, the effect of AMFE on DPPH, ABTS, and ·OH free radical scavenging abilities was determined. The concentrations at which AMFE exhibited over 90% scavenging rate for ABTS and DPPH free radicals were found to be 0.125 mg/mL and 2 mg/mL, respectively.

Investigating AgCl-SnO2 nanocomposite for photocatalytic degradation of azo dye, associated reaction pathways, and its antibacterial activity

Herein, AgCl-SnO2 nanocomposite (NC) fabricated through a facile hydrothermal method exhibit substantial potential as an efficient and economical photocatalyst and bactericidal agent. The formation of spherical AgCl-SnO2 NC was confirmed through PXRD and SEM, with an average crystalline size of 12 nm. DR spectra and Kubelka-Munk function were used to determine the band gaps of AgCl (3.10 eV) and SnO2 (3.48 eV). The synthesized NC achieve successful photocatalytic degradation (98 %) of orange-G (OG) dye within 60 min. The NC’s potential was also elucidated by investigating the role of sacrificial reagents. Formation of •OH free radicals is confirmed from photoluminescence studies using terephthalic acid. The effective degradation of OG dye has been substantiated, resulting in the generation of numerous intermediate products with reduced toxicity, such as substituted phenols and aromatic dicarboxylic compounds. Furthermore, the NC demonstrated excellent efficiency even after six consecutive cycles, indicating its stability, regenerative property, and recyclability. The NC also exhibits significant antimicrobial activity against Escherichia coli.

Extraction, Purification, and in vitro Antioxidant Activity Assessment of Total Flavonoids from the Aerial Parts of Tetrastigma hemsleyanum

Background The effective extractives of Tetrastigma hemsleyanum ( T. hemsleyanum) are useful, but this plant was not fully utilized in rural China. In this study, flavonoids from the aerial parts of T. hemsleyanum were extracted, and the purification method and the antioxidant capability were explored. Purpose This study is to explore the optimized purification method and the biological capability of the total flavonoids extracted from T. hemsleyanum. Materials and Methods The optimal extraction conditions were determined by single-factor and Box-Behnken design experiments. The antioxidant activities were assessed by analyzing their capability to scavenge 2,2-diphenyl-1-picrylhydrazyl and OH free radicals. Results and Discussion The optimal conditions for the extraction of the total flavonoids were as follows: ethanol volume fraction 60%, liquid-to-material ratios 35:1 mL/g, temperature 45℃, and time 85 min. The extraction rate of the total flavonoids was (3.59 ± 0.03)%. NKA-9 is an ideal macroporous resin for purification. The optimized purification process conditions of flavonoids were mass concentration of adsorption solution 1.50 mg/mL, pH value of adsorption solution 4.0, sample loading flow rate 2 BV/h, ethanol volume fraction in desorption process 60%, desorption flow rate 2 BV/h and elution volume 4 BV. After crude extracts were purified by NKA-9 macroporous resin, the content of the total flavonoids enhanced from (21.76 ± 0.18)% to (58.92 ± 0.22)%. The results of the experiments for antioxidant activity showed that the half maximal inhibitory concentration (IC50) values of the purified flavonoids extracted were 33.1and 42.7 µg/mL, respectively. Conclusion The results of this study indicated that the flavonoids in T. hemsleyanum have good antioxidant activity in vitro and deserve exploring in further pharmacological studies.

Tailored Polymeric Carbon Nitride Coupled with Bi2O3 for Constructing Z‐Scheme Heterojunction with Enhanced Photocatalytic Activity

AbstractThe great demand for visible‐light‐induced catalysts with high photocatalytic performance has stimulated extensive interest in constructing g‐C3N4‐based Z‐Scheme heterojunctions. In this research work, the g‐C3N4/Bi2O3 Z‐Scheme heterojunction by precipitation‐hydrothermal method was constructed, and characterized by various techniques. The g‐C3N4/Bi2O3‐1 composite exhibited a transient photocurrent response approximately 7 and 5 times higher than that of bare g‐C3N4 and Bi2O3, respectively, and showed higher visible photocatalytic activity with 99.8 % degradation of methylene blue (MB) within 75 min. Meanwhile, the pH effect on the photocatalytic degradation of MB was investigated. Radicals trapping experiments showed that •OH free radical played a predominant role for the degradation of MB, EPR analysis confirmed the presence of superoxide radicals, which combined with the band structure of the composites, confirmed the Z‐Scheme of the heterojunction. A possible mechanism for photocatalytic degradation of MB dyes in g‐C3N4/Bi2O3‐1 composites was also proposed. This study provided a new avenue for the development of novel g‐C3N4‐based Z‐Scheme heterojunction materials with prospective applications in the fields of energy and environment.

Construction of CuFe2O4/Bi2MoO6 heterogeneous catalyst for high-efficiency photocatalytic degradation of levofloxacin under visible light: Mechanism, pathways and DFT calculation

The utilization of solar energy to stimulate semiconductor photocatalytic degradation is a sustainable method for environmental remediation. CuFe2O4/Bi2MoO6 was synthesized for the degradation of levofloxacin by successfully loading CuFe2O4 nanoparticles on the surface of Bi2MoO6 microflower by a simple sol-gel and hydrothermal method. Comprehensive characterizations confirmed the formation of a heterojunction structure between CuFe2O4 and Bi2MoO6. Owning to the strong synergistic effect between CuFe2O4 and Bi2MoO6, involving higher surface area and pore volume, multiple metal ion reaction centers enriched the charge transfer pathways, heterojunction structure facilitated charge migration and reduced electron-hole complexation, the optimal CBM-10 composite catalysts showed high degradation efficiency of LVF with 95.1% in 60 min, and robust structural stability after five cycle experiments. The free radical scavenging test and DFT calculations revealed that three possible reaction pathways for photocatalytic degradation of LVF by combining the analysis of intermediates by HPLC-MS and h+, •O2- and •OH free radical were the main active species.

Physicochemical Characterization, Antioxidant and Anticancer Activity Evaluation of an Acidic Polysaccharide from Alpinia officinarum Hance.

AHP-3a, a triple-helix acidic polysaccharide isolated from Alpinia officinarum Hance, was evaluated for its anticancer and antioxidant activities. The physicochemical properties and structure of AHP-3a were investigated through gel permeation chromatography, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The weight-average molecular weight of AHP-3a was 484 kDa, with the molar percentages of GalA, Gal, Ara, Xyl, Rha, Glc, GlcA, and Fuc being 35.4%, 21.4%, 16.9%, 11.8%, 8.9%, 3.1%, 2.0%, and 0.5%, respectively. Based on the results of the monosaccharide composition analysis, methylation analysis, and NMR spectroscopy, the main chain of AHP-3a was presumed to consist of (1→4)-α-D-GalpA and (1→2)-α-L-Rhap residues, which is a pectic polysaccharide with homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) structural domains containing side chains. In addition, the results of the antioxidant activity assay revealed that the ability of AHP-3a to scavenge DPPH, ABTS, and OH free radicals increased with an increase in its concentration. Moreover, according to the results from the EdU, wound healing, and Transwell assays, AHP-3a can control the proliferation, migration, and invasion of HepG2 and Huh7 hepatocellular carcinoma cells without causing any damage to healthy cells. Thus, AHP-3a may be a natural antioxidant and anticancer component.

Identification, Nutrient Composition, and Evaluation of a Wild Pleurotus citrinopileatus Strain (X21156) from Tibet for Antioxidant and Cytotoxic Activities

A fungal strain (X21156) collected in Tibet was used as the material, identified based on its morphological characteristics and internal transcribed spacer (ITS) sequence; its optimal culture conditions were analyzed by single-factor experiments; artificial domestication and cultivation were carried out; its nutrient composition was determined; and the bioactivities of its polysaccharides were detected using chemical antioxidant assays and MTT assays. The results showed that the strain was Pleurotus citrinopileatus Sing. Its optimal culture conditions were a pH of 7, a temperature of 25 °C, glucose (20 g·L−1) as the carbon source, and yeast powder (20 g·L−1) as the nitrogen source. The fresh weight of a single domesticated fruiting body was 41.16 g. The strain had high protein (28.5%), high fiber (34%), and low fat (1.4%) contents, with high proportions of fresh and sweet amino acids. Polysaccharides had good scavenging ability on ABTS+, DPPH, and OH free radicals (EC50 0.06 mg/mL, 1.21 mg/mL, and 3.62 mg/mL, respectively), and the cytotoxicity of polysaccharides to hepatocellular carcinoma cells (HepG2) (IC50: 1.69 mg/mL) was higher than that of triple-negative breast cancer cells (MDA-MB-468) (IC50: 1.76 mg/mL). In conclusion, the study provides a reference on the optimal culture conditions, domestication and cultivation, and dietary and medicinal values of wild P. citrinopileatus Sing.

Optimization of Extraction Process and Activity of Angiotensin-Converting Enzyme (ACE) Inhibitory Peptide from Walnut Meal.

In order to further realize the resource reuse of walnut meal after oil extraction, walnut meal was used as raw material to prepare polypeptide, and its angiotensin-converting enzyme (ACE) inhibitory activity was investigated. The ACE inhibitory peptides were prepared from walnut meal protein by alkaline solution and acid precipitation. The hydrolysis degree and ACE inhibition rate were used as indexes to optimize the preparation process by single-factor experiment and response surface method. The components with the highest ACE activity were screened by ultrafiltration, and their antioxidant activities were evaluated in vitro. The effect of gastrointestinal digestion on the stability of walnut peptide was analyzed by measuring molecular weight and ACE inhibition rate. The results showed that the optimal extraction conditions were pH 9.10, hydrolysis temperature 54.50 °C, and hydrolysis time 136 min. The ACE inhibition rate of walnut meal hydrolysate (WMH) prepared under these conditions was 63.93% ± 0.43%. Under the above conditions, the fraction less than 3 kDa showed the highest ACE inhibitory activity among the ACE inhibitory peptides separated by ultrafiltration. The IC50 value of scavenging ·OH free radical was 1.156 mg/mL, the IC50 value of scavenging DPPH free radical was 0.25 mg/mL, and the IC50 value of scavenging O2- was 3.026 mg/mL, showing a strong total reducing ability. After simulated gastrointestinal digestion in vitro, the ACE inhibitory rate of walnut peptide decreased significantly, but it still maintained over 90% ACE inhibitory activity. This study provides a reference for the application of low-molecular-weight walnut peptide as a potential antioxidant and ACE inhibitor.

Optimization of Solid-State Fermentation Process of Radix Ranunculi ternate Using Response Surface Method and Addressing Its Antioxidant and Hypoglycemic Activity

Objective: The aim of this study was to optimize the fermentation process of Radix Ranunculi ternate via microbial fermentation and analyze the changes in the contents of the main components, the antioxidant and hypoglycemic capacities of the extract before and after fermentation. Methods: The solid-state fermentation process was optimized using single-factor tests and the response surface method, with the yield of the alcohol extract of R. ternate as an evaluation index. Results: The best fermentation process was optimized using solid-state endophytic fungus fermentation technology as follows: strain addition ratio of Chaetomium globosum/Fusarium equiseti = 1:1, fermentation for 5 d, sieve size of 40 mesh, liquid/material ratio of 0.8:1 mL·g−1, fermentation temperature of 31 °C, and inoculation amount of 7.5%. Under the optimized conditions, the contents of the water-soluble extract and total polysaccharides decreased by 12.71% and 12.95%, respectively. In the fermentation, the contents of the ethanol-soluble extract, flavonoids, saponins, polyphenols, organic acids, and total amino acids of the fermented R. ternate increased by 19.77%, 57.14%, 79.67%, 14.29%, 17.63%, and 3.82%, respectively. The scavenging rate for DPPH, ABTS+, and ·OH free radicals and inhibitory rate for α-amylase of the fermented R. ternate also increased by 19.02%, 14.17%, 7.53%, and 34.54%, respectively, compared with the unfermented R. ternate. Conclusions: Solid-state fermentation opens new avenues for the development and application of R. ternate as a natural antioxidant and hypoglycemic food.

Ni3Se4/ZnIn2S4 S-scheme heterojunction for efficient photocatalytic H2 evolution

Photocatalytic water splitting is sustainable technology to obtain green H2. Herein, Ni3Se4/ZnIn2S4 heterojunction was obtained through a two-step hydrothermal method. 5 wt% Ni3Se4/ZnIn2S4 exhibits the most excellent H2 evolution performance and the H2 evolution rate can achieve 38778.0 μmol·g−1·h−1, which is 5.94 times higher than that of pure ZnIn2S4. Based on the ·OH free radical capture tests, the enhanced activity is attributed to S-scheme carriers migration mechanism and the abundant Se sites in Ni3Se4 can rapidly capture H+ to produce H2 efficiently. This work expands the application of transition metal selenides in the field of photocatalysis.

Tailoring Bandgap and Photocatalytic Performance of Designed Zinc Oxide Platelets by Cobalt Doping

AbstractPlatelet‐shaped zinc oxide (ZnO) particles exhibit certain advantages compared to conventional micron and nano forms. Their superior surface coverage and excellent optical properties make these particles very attractive as UV filters in cosmetics and personal care applications. Although ZnO is non‐toxic, it exhibits photocatalytic activity (PCA), which increases when the size of particles approaches the nanoscale. High PCA of mineral/inorganic filters is not desired in cosmetics and personal care applications. Therefore, it is essential to develop strategies to reduce PCA of such materials under UV exposure. Accordingly, the research objective of this study is to develop an understanding of the effects of Co‐doping on the optoelectronic and crystal structure of platelet shaped ZnO particles with Zn1‐xMxO stoichiometry (x=0‐4 wt % cobalt). XRD‐based Rietveld refinement and WD‐XRF reveal that Co was successfully doped into the ZnO lattice. SEM and particle size analyses confirmed that the shape and size of the designed ZnO platelets did not change significantly after doping. ~85 % reduction in PCA has was achieved by 3 wt % Co doping which was attributed to reduced OH and O2 free radical concentration. These results clearly show that Co‐doping can be used to effectively tailor the bandgap and optical properties of the designed ZnO particles.

Yoga meditation: A path to holistic health and healing

The word meditation is derived from a Latin word ‘madri’ which means “to heal”. Meditation can certainly be considered as a great healing process - spiritual, mental, and emotional - with proven benefits to physical well-being. In the current communication, an attempt has been made to explain some of these benefits and provide science based evidence to explain them. Meditation develops our ability to maintain inner peace at all times in our actions and thereby achieve the best physical and mental health. With psychosomatic ailments, meditation provides the vital element that modern therapies lack. During Yogic breathing, some of the oxygen generates •OH free radicals according to the Haber Weiss process, which immediately react with glucose molecules to oxidize them. Some of these oxidation products are very useful, such as gluconic acid, which removes some undesirable metals from the body. Additionally, glucuronic acid is another product, and it is part of the natural detoxification process found in the body. It removes harmful toxins and is used in the treatment of prostate cancer. Another product, D-glucarate, has been shown to decrease lung, skin, liver, breast, and colon cancers by 60%. The product Calcium-D-glucarate lowers cholesterol by 12%, LDL by 28%, and triglycerides by 43%. Lastly, D-glucono 1,4 lactone, with further reactions with •OH, is converted to D-glucaro 1,4 lactone and is a powerful liver detoxifier. Meditation boosts intelligence, IQ score, and increases the gray matter of the brain. The relaxation response decreases breathing rate and oxygen consumption by 20%. It lowers heart rate and brings blood pressure to normal levels. During meditation alpha waves of the brain are generated. This brings relaxation and serenity of mind, helping people to better cope with stress. According to the British Heart Foundation, 15 minutes of meditation a day can reduce the risk of death, heart attack and stroke by 48%. According to Dr. Dean Ornish, meditation can help in reversing heart disease. Meditation has the power to change our negativity of mind and reshape our thoughts into a more positive direction to improve our mental well-being.