Chemical Activation Research Articles

Multivariate analysis of the phytochemical composition and antioxidant properties in twenty-five accessions across three Achillea species

This study explored the chemical composition, antioxidant activity, and total phenol content of aerial parts from 25 accessions of three Achillea species (Achillea wilhelmsii C. Koch, Achillea vermicularis Trin., and Achillea tenuifolia Lam.). The plants were collected from various natural habitats across Iran, encompassing regions such as Central, Western, Southern, Northern, Western, and Northwestern parts of the country. Subsequently, they were grown together under field conditions. The study revealed significant variation in essential oil yields among accessions of A. wilhelmsii, ranging from 0.01 to 0.107%, A. vermicularis with a range of 0.075 to 1.5%, and A. tenuifolia showing a variation of 0.1 to 2%. The study utilized Gas Chromatography–Mass Spectrometry (GC–MS) analysis, revealing 75, 49, and 75 compounds in the essential oils of A. wilhelmsii, A. tenuifolia, and A. vermicularis, respectively. Major components included camphor, 1,8-cineole, anethole, α-pinene, and phytol in A. wilhelmsii, 1,8-cineole, camphor, levo-carvone, and δ-terpinene in A. vermicularis, and β-cubebene, elixene, β-sesquiphellandrene, 1,8-cineole, camphor, and δ-terpinene in A. tenuifolia. The essential oil compositions of A. wilhelmsii and A. vermicularis were predominantly characterized by oxygenated monoterpenes, whereas that of A. tenuifolia was characterized by sesquiterpenes. Cluster analysis grouped accessions into three clusters, with A. tenuifolia forming a distinct group. Principal Component Analysis (PCA) triplot (62.21% of total variance) confirmed these results and provided insights into compound contributions. Furthermore, total phenolic content and antioxidant activity of the accessions of three species were assessed over 2 years. A. tenuifolia exhibited the highest levels in both categories, with statistically significant linear regression between antioxidant activity and total phenol content for A. tenuifolia and A. wilhelmsii. These findings emphasize significant phytochemical diversity within Achillea species, positioning them as promising natural sources of antioxidants. Further exploration and selection of specific accessions within each species are crucial for unlocking their medicinal potential and supporting cultivation and conservation efforts.

Process Development for the Enzymatic Gram-Scale Production of the Unnatural Nucleotide Sugar UDP-6-Azido-GalNAc.

Azido sugars hold great promise as substrates in numerous click-chemistry applications. However, the synthesis of activated azido sugars is limited by cost and complexity. Conventional chemical activation methods are intricate and time-consuming. In response, we have developed a process for the large-scale production of UDP-6-azido-GalNAc through enzymatic nucleotide sugar synthesis on a gram scale. Our optimization strategies encompassed refining the process parameters of an enzyme cascade featuring NahK from Bifidobacterium longum and AGX1 from Homo sapiens. Using the repetitive-batch-mode technology, we synthesized up to 2.1 g of UDP-6-azido-GalNAc, achieving yields up to 97 % in five consecutive batch cycles using a single enzyme batch. The synthesis process demonstrated to have total turnover numbers (TTNs) between 4.4-4.8 g of product per gram of enzyme (gP/gE) and STYs ranging from 1.7-2.4 g per liter per hour (g*L-1*h-1). By purification of a product solution pool containing 2.6 g (4.1 mmol) UDP-6-azido-GalNAc, 2.1 g (2,122.1 mg) UDP-6-azido-GalNAc (sodium salt) with a purity of 99.96 % (HPLC) were obtained. The overall recovery after purification was 81 % (3.32 mmol). Our work establishes a robust production platform for the gram-scale synthesis of unnatural nucleotide sugars, opening new avenues for applications in glycan engineering.

Effect of Lentinus sajor-caju on the chemical composition and antioxidant activity of highland barley straw under solid-state fermentation.

The efficient utilization of straw resources as animal feed has gained considerable attention. The objective of this study was to evaluate whether Lentinus sajor-caju treatment alters the chemical composition and antioxidant activity of highland barley straw and enhances its functional value as a ruminant feed. The chemical composition, antioxidant capacity, and metabolomic profile of highland barley straw were determined after 21 days of solid-state fermentation with L. sajor-caju at 25°C. The differential metabolites between fermented and unfermented highland barley straw were identified by LC-MS and the relationship between the identified metabolites and antioxidant capacity was elucidated. The results showed that, compared with untreated highland barley straw, the crude protein and ether extract contents were higher (51.55 and 76.43%, respectively) in highland barley straw after 21 days of incubation with L. sajor-caju, whereas the hemicellulose, cellulose, and acid detergent lignin contents were lower (2.48, 25.08, and 45%, respectively). The total antioxidant capacity was significantly higher in L. sajor-caju-treated than in untreated highland barley straw. In total, 600 differential metabolites (301 upregulated and 299 downregulated) were identified between L. sajor-caju-fermented and unfermented highland barley straw. Correlation analysis results showed that Fe2+ scavenging and total phenolic content were strongly correlated with total antioxidant capacity. Meanwhile, the differential flavonoid metabolites between fermented and unfermented highland barley straw were primarily associated with antioxidant activity, with kaempferol 3-xylosylglucoside, isoginkgetin, and rhoifolin being the most representative. Thus, this study demonstrates that L. sajor-caju could enhance the functional value of highland barley straw, showing the potential of L. sajor-caju for improving the utilization of agricultural straws in ruminants.

Chemical Structures, Biological Activities, and Biosynthetic Analysis of Secondary Metabolites from Agaricus Mushrooms: A Review.

Agaricus mushrooms are an important genus in the Agaricaceae family, belonging to the order Agaricales of the class Basidiomycota. Among them, Agaricus bisporus is a common mushroom for mass consumption, which is not only nutritious but also possesses significant medicinal properties such as anticancer, antibacterial, antioxidant, and immunomodulatory properties. The rare edible mushroom, Agaricus blazei, contains unique agaricol compounds with significant anticancer activity against liver cancer. Agaricus blazei is believed to expel wind and cold, i.e., the pathogenic factors of wind and cold from the body, and is an important formula in traditional Chinese medicine. Despite its nutritional richness and outstanding medicinal value, Agaricus mushrooms have not been systematically compiled and summarized. Therefore, the present review compiles and classifies 70 natural products extracted from Agaricus mushrooms over the past six decades. These compounds exhibit diverse biological and pharmacological activities, with particular emphasis on antitumor and antioxidant properties. While A.blazei and A.bisporus are the primary producers of these compounds, studies on secondary metabolites from other Agaricus species remain limited. Further research is needed to explore and understand the anticancer and nutritional properties of Agaricus mushrooms. This review contributes to the understanding of the structure, bioactivity, and biosynthetic pathways of Agaricus compounds and provides insights for the development of functional foods using these mushrooms.

Modulation of metal-organic frameworks by anionic surfactants for rapid adsorption of organic pollutants bisphenol A and chrome black T

With the accelerated development of industry, which generates large quantities of sewage discharged into the aquatic environment, serious impacts on both environmental and human health. Detecting various organic contaminants in water sources has become common, presenting huge challenges for water treatment. Metal-organic frameworks are characterized by their rich porous structures and high chemical activity, making them ideal adsorbents for removing organic pollutants from water. In this study, sodium dodecylbenzene sulfonate is added to the precursor solution of MIL-101(Cr)-Cl2 and synthesized hierarchical porous structure adsorbents MIL-SDBS-X, using hydrothermal synthesis to enhance their adsorption capacity, making efficient and rapid removal of bisphenol A(BPA) and chromium black T(EBT), two common organic pollutants in water, which MIL-SDBS-0.7 was the most effective. MIL-SDBS-0.7 exhibites great potential in the adsorption of BPA and EBT for its high adsorption capacity (260.5 mg-1·g-1 and 272.3 mg-1·g-1) and rapid adsorption (equilibrium could be achieved in 15 minutes), The findings reveal adsorption kinetics aligns with the pseudo-second-order model and the Langmuir equation best fits to study adsorption of MIL-SDBS-0.7 to BPA and EBT. Thermodynamic parameters affirm the exothermic and higher spontaneity behavior of the adsorption process. Moreover, the adsorption mechanism of MIL-SDBS-0.7 was explored, illustrating the crucial roles of effects of hydrogen bonding π-π stacking and pore filling in the adsorption of BPA and EBT. Therefore, this work not only provided a convenient strategy for the preparation of efficient and fast MIL-SDBS-0.7 hierarchical porous material but also highlighted the promising potential of synthesized absorbents as an effective adsorbent for organic pollutants in wastewater treatment and environmental remediation.

Laser-induced nitrogen and phosphorus-doped spongy carbon with graphene wings derived from lignin for significantly enhanced capacitance deionization performance

Efficient capacitive deionization (CDI) technology puts forward higher requirements for electrode materials. However, the traditional process of preparing porous carbon (PC) electrodes by alkaline chemical activation is polluting and energy-consuming. In this work, the N/P co-doped biocarbon material (H-AL/APP) was prepared by using alkali lignin (AL) and ammonium polyphosphate (APP) as carbon precursors based on laser-induced carbonization and hydrothermal activation technology. The as-prepared carbon material shows a three-dimensional (3D) structure with a hierarchical porous structure, large specific surface area of 405.98 m2/g (SSA), excellent pore volume, and outstanding mesoporosity. Compared with commercial YP80 activated carbon, The H-AL/APP electrode exhibits a higher specific capacitance of 210F/g with excellent rate performance and cycle stability. When assembled for desalination, H-AL/APP shows the highest removal rate of 23 mg/g/min with an outstanding desalination capacity of 34.6 mg/g than those of YP80 activated carbon. Furthermore, reasonable cycle stability and reproducibility highlight their promising application prospects. In summary, this work provides a green, efficient, and economical method for preparing high-performance heteroatom-doped PCs for efficient CDI desalination.

Chemical profiling and biological activities of the roots of Allochrusa gypsophiloides

Allochrusa gypsophiloides is one of the best-known endemic saponin bearing food plants of Central Asia. However, the plant’s secondary metabolites remain unmapped. The current study aimed to chemical profile of the metabolite in the plant roots by an untargeted UHPLC-ESI-MS, together with the isolation of the major compounds followed by a 2D NMR and HR-MS for identification and evaluation of the antioxidant and enzyme inhibitory activity of the extracts. The results revealed the presence of 48 putatively annotated metabolites comprising triterpene glycosides, phenolic compounds and their derivatives, organic acid glycosides, and lignan glycosides. The chromatographic separation and purification of the extract resulted in the isolation of four compounds where two new compounds and along with two known triterpenes were reported. The ethanol/water extracts showed a maximum effect in antioxidant assays, while the ethyl acetate extract achieved the best effect in the enzyme inhibitory assays.

Chemical composition and antioxidant activity of Tagetes filifolia Lag. essential oil from Peruvian Andes

The chemical composition of the essential oil from the aerial parts (leaves and flowers) of Tagetes filifolia Lag. grown in the Peruvian Andes was examined throughout the gas chromatography and gas chromatography-mass spectrometry techniques. Fifty-seven compounds were identified representing more than 99% of the essential oil. Phenylpropanoids had the major percentage, including (E)-anethol (85.0%) and estragole (12.9%) as the most abundant compounds. A multivariate analysis was performed using hierarchical cluster analysis to examine the relationship between the studied sample and other T. filifolia specimens from 21 essential oil compositions reported in the literature. Agglomerative hierarchical cluster analysis reveals three groups: (E)-anethole/estragole, estragole/(E)-anethole and an outlier (Z)-anethole/estragole. In addition, antioxidant activity was evaluated using 1,1-diphenyl-2-picryl-hydrazyl and ferric reducing antioxidant power assays. The essential oil had a moderate scavenging effect and ferric reducing capacity.

Electronic Effect Driven Specific and Sensitive Recognition toward GHB.

Precise detection of a trace substance that intrinsically possesses weak chemical activity and less-distinctive spatial structure is of great significance, but full of challenges, as it could not be effectively recognized via either an active covalent reaction process or multiple noncovalent interactions toward its simple structure. Here, the electronic-effect-driven recognition strategy was proposed to visually sense an illicit drug, γ-hydroxybutyric acid (GHB), which was treated as an analyte model due to its inherent simple structure. In particular, a sensing system composed of two probes substituted by the nitro (-NO2) and the hydrogen (-H), was constructed with the characteristic yellow coloring and blue fluorescence, as well as high sensitivity (0.586 ng/mL), fast response (0.2 s), and specific recognition, even in the presence of 22 interferents. In addition, a portable eyeshadow box-like sensing chip was fabricated and proven to be reliable and feasible in sensing GHB disguised in liquors for self-protection in a covert manner. Hence, this work developed an electronic-effect-driven modulation strategy of the recognition interaction between the probe and the analyte and, thus, would open up a new thought for detecting the analyte with weak activity and a simple structure, as well as propel the relevant application in real scenarios.

Novel activation method of waste concrete powder for sustainable clinker-free binder

This study investigates the environmental and mechanical implications of incorporating silica fume into lime-activated thermo-mechanically treated waste concrete powder (TMWCP) to develop a sustainable clinker-free binder. The novel activation method involves thermo-mechanical treatment of WCP, followed by lime and calcium formate chemical activation. The results demonstrated that incorporating silica fume enhanced the pozzolanic reactivity, which led to the formation of C–S–H, pore refinement, and a dramatic increase in compressive strength. For instance, the incorporation of 20 % and 25 % silica fume exhibited compressive strength of 46 MPa and 43 MPa after 28 days of curing. The developed clinker-free binder with the addition of 20 % silica fume demonstrated a reduction in mineral resource consumption of 99.3 % and CO2 emissions of 13 % and 69.3 % compared to the sample without silica fume and ordinary Portland cement, respectively. This study offers a promising avenue for the widespread utilization of WCP as an environmentally friendly clinker-free binder.

The prospect of compiling a soil-improving mixture based on local natural resources with their chemical activation with nitric acid

In agrochemistry, a promising direction can be considered the preparation of soil-improving mixtures consisting of local, relatively cheap natural resources. These include phosphorites and phosphate rock prepared from them, limestone, dolomites, and can also include loam (overburden rock). One should expect an increase in their agrochemical efficiency when using modifying acids, in particular nitric acid, for the purpose of chemical activation (as a result of nitrate decomposition) of nutrients while simultaneously enriching soil-improving mixtures with nitrogen. The purpose of the research is to study the chemical activation of loam and phosphate rock with nitric acid (65%) when preparing a soil-improving mixture (SUMS). We proceeded from the composition of the PUUS with the ratio phosphate rock: dolomite: PS: nitric acid as 1:0.6:1:0.8. The work was carried out based on materials from laboratory experiments. In the experiments, the chemoactivating effect was considered at the level of individual components. This is due to the lack of appropriate GOST standards for a multicomponent mixture. Therefore, the data on the chemical composition have approximate values, because eliminated the influence of the components on each other and the immediate influence of nitric acid on them. However, it is possible to indicate the approximate values of the main agrochemical indicators of the PUUS: the content of total nitrogen 9,0%, total phosphorus – 19%, digestible and water-soluble forms of phosphorus 7,0 and 3,5% (according to the FM + dolomite + double treatment with HNO3), total potassium 0,2% (approximately based on cover loam).

Reduction of Metal Density of Iron (Fe) and Natrium Minerals (Na) in Boring Water Using Rubber Fruit Sheets Active Archoic

Activated carbon is a highly popular adsorbent for the absorption of metal ions. Lignocellulosic materials can be used to produce activated carbon, which is both renewable and abundant, as well as being cost-effective. The objective of this research is to investigate the reduction of iron (Fe) and sodium (Na) levels in the artesian well by utilizing activated carbon made from rubber shells. The materials utilized include rubber shells, a solution containing 10% H3PO4 (phosphoric acid), water from an artesian well, and distilled water (aquadest). The carbonization process was conducted at 300º C for 1 h, using an adsorbent size of 120 mesh. In addition, chemical activation was performed using a 10% H3PO4 solution for 24 h, followed by physical activation through heating in a furnace at a temperature of 500ºC for 1 hour. The acquired activated carbon is utilized for the absorption of Fe and Na. The activated carbon was characterized using X-ray diffraction (XRD), and the concentration of Fe and Na minerals was determined using an Atomic Adsorption Spectrophotometer (AAS). The results indicated a reduction of 97.9% in the concentration of iron (Fe) and a decrease of 90.01% in sodium (Na) levels.

Fe-doped biomass-derived activated carbons as sustainable electrode materials in supercapacitors using different electrolytes

In the search of sustainable and low-cost materials, able to reinforce circular economy, different activated carbons were obtained from agroindustry wastes, by means of a chemical activation route, after the doping of their corresponding biochars with Fe-based species through an incipient wetness method. These activated carbons were assessed as active electrode materials in supercapacitors using various electrolytic media, including aqueous, organic and ionic liquid electrolytes. The electrochemical results obtained revealed an excellent performance for all porous materials and electrolytes under evaluation, reaching the highest specific capacitance of 334F/g at a current density of 0.02 A/g using an aqueous electrolyte. The highest specific capacitance using an organic electrolyte and an ionic liquid electrolyte were 214F/g and 166F/g, respectively. It was found that activated carbons with a relevant mesopores volume, and pore sizes around 1 nm, achieved a better specific capacitance when using aqueous and organic electrolytes. However, heteroatoms as oxygen and iron enhanced the electrochemical performance of the device using the ionic liquid as electrolyte, thus achieving the highest energy and power density values (up to 63 Wh/kg and 1606 W/kg, respectively) among the different systems evaluated.

Effect of temperature on the chemical activation of carbon nanospheres and their efficiency in supercapacitors

We report the synthesis of carbon spheres (CSs) by pyrolysis of soybean oil and their chemical activation employing acid baths at different temperatures. This allows to study the effect of these experimental parameters on the efficiency of these materials for their use as supercapacitor electrodes. The CSs were characterized by SEM, Raman, XRD, FT-IR, BET, and TEM to reveal the relationship between the electrochemical properties and the structure. Using nitric acid as the activating agent causes the formation of micropores and a high density of oxygenated functional groups in the CSs. In contrast, the mixture of sulfuric and nitric acids destroys the CSs, producing coalescence. The capacitance of the CSs was ~103 F g−1 at 5 mV s−1, and the contribution of electrical double-layer capacitance and pseudocapacitance was determined using cyclic voltammograms. Moreover, it is observed that after 1000 galvanostatic charge-discharge cycles at 2 A g−1, the CSs with the larger electrochemical capacitance increase their capacitive performance up to 38 %, maintaining the electrical double-layer capacitance contribution constant. Therefore, we show that controlling the density of oxygenated functional groups anchored through an increase in temperature during acid treatment and generating high surface areas are key parameters to obtain high capacitance.

Pyrolysis solid product as a sorbent for flue gases mercury capture — Part II: Sorbent utilization

This study explores using solid pyrolysis products from six materials as sorbents to capture mercury from flue gas in an experimental fluidized bed combustor. It investigates the effects of activation methods, adsorption temperature, and Hg0/Hg2+ ratios on mercury removal efficiency. Physical and chemical activations are conducted using steam and NaOH, respectively. Tests are run at 100–160 °C with 5 g of sorbent. Results show 120 °C as optimal, with sorbents losing 0.34 % and 0.39 % efficiency with increasing temperature for lignite and black coal. Specific surface area (up to 641 m2∙g–1) significantly influences cumulative removal efficiency (CRE), reaching 80.8 % for lignite and 73.85 % for black coal. Mercury gas recovery averages 35.5 % and 53.7 % after physical and chemical activations. Lignite sorbents exhibit higher CRE than black coal, indicating greater mercury oxidation in black coal flue gas. This study offers a promising method for char recovery from pyrolysis, suggesting competitive sorbents for industrial use.

The study of the influence of <i>Thlaspi arvense</i> L. on the characteristics of the reproductive system of male rats

Introduction. The development of new effective and safe herbal medicines capable of having a positive effect on reproductive status is an urgent task of domestic pharmacy. Medicinal plants are considered as alternative therapies aimed at increasing testosterone levels and fertility in men. The arsenal of medicinal plants used in traditional medicine for the treatment of diseases in men is mainly represented by phytoadaptogens, most of which have a small resource potential in Russia, therefore, it is relevant to search for plants with a sufficient raw material base and with the potential for cultivation. Thlaspi arvense L. is a promising medicinal plant, as it is widely used in folk medicine as a diuretic, anti-inflammatory, diaphoretic, antihistamine, hemostatic, astringent, has a positive effect on the processes of spermatogenesis and is widely distributed in our country. However, information on the chemical composition and biological activity of Thlaspi arvense L. they are insufficient, which shows the relevance of its further more detailed study in order to substantiate the possibility of application in practical medicine and solutions to the issues of standardization of medicinal plant raw materials.Aim. The study of the influence of Thlaspi arvense L. on the characteristics of the reproductive system of male rats.Materials and methods. The object of the study was an infusion of herbа Thlaspi arvense L. The features of the reproductive behavior of male rats after 21-day administration of the infusion of grass yarutka field were studied using tests that allow quantifying the severity of sexual motivation and sexual activity of males. The viability of spermatozoa in the ejaculate of rats was assessed, the total number of spermatozoa (ACS, million), degenerative and immobile forms (%) was calculated. Morphophysiological parameters of spermatogenesis of rats of control and experimental groups of animals were studied using classical histological methods. The concentration of testosterone in the blood serum of experimental groups of animals was determined by the enzyme immunoassay.Results and discussion. The results obtained allow us to conclude that the fertility of rats has increased against the background of the course administration of the infusion of herbа Thlaspi arvense L., as evidenced by an increase in the testosterone content in the blood, improvement of spermogram indicators and morphophysiological characteristics of spermatogenesis in the testicles of rats. The use of the infusion of herbа Thlaspi arvense L. has a protective effect on spermatogenesis. An increase in the thickness of the spermatogenic epithelium, the diameter of the cross-section of the convoluted seminal tubules and the index of spermatogenesis compared with the control group of animals was revealed. The positive effect of Thlaspi arvense L. on indicators of sexual motivation and sexual activity of male rats is shown.Conclusion. Thlaspi arvense L. is a promising medicinal plant, as it is able to have a positive effect on libido, the number and mobility of spermatozoa, the production of sex hormones, spermatogenesis, as well as on the pituitary-gonadal axis, which is associated with the content of a complex of biologically active substances in it.

Two-step modification strategy enhances carbon fiber/old corrugated container fiber flexible conductive film

Carbon fiber (CF) possesses inherent properties of low density, high strength, and environmental stability. Its high aspect ratio and knittability enable the formation of flexible conductive networks. Old corrugated container (OCC) is rich in cellulose and hemicellulose, rendering them flexible and exhibiting a low coefficient of thermal expansion. In this paper, CF/OCC/PVA flexible conductive films were prepared using polyvinyl alcohol (PVA) as the matrix, CF as the conductive filler and OCC as the flexible support material. Firstly, the coupling agent was grafted on the surface of CF to enhance their surface activity, improve the dispersion of CF in solution and the chemical bonding of CF to the matrix. Subsequently, sizing nanoparticles were applied to increase the roughness of the CF surface. This served to increase the volume of the conductive network and enhance the mechanical interlocking between CF and PVA. The results show that the two-step combined modification strategy have a significant positive impact on the interfacial chemical activity, contact angle, and roughness of CF. Moreover, it leads to notable improvements in various properties of the conductive film materials. This finding is relevant for the preparation of CF reinforced other matrix materials as well as for expanding the special properties and application value of CF conductive thin film materials.

From scraps to purification: innovative use of food waste-derived hydrochar in eradicating pharmaceutical pollutants.

Chemical products (CPs) such as carbamazepine and naproxen, present in aquatic environments, pose significant risks to both aquatic life and human health. This study investigated the use of hydrothermally carbonized food waste-derived hydrochar (AC-HTC) at three distinct temperatures (200, 250, and 300°C) as an adsorbent to remove these CPs from water. Our research focused on the impact of hydrothermal carbonization temperature on hydrochar properties and the effects of chemical activation with phosphoric acid on adsorption capacity. Hydrothermal carbonization increased the hydrochar's surface area from 1.47 to 7.52 m2/g, which was further enhanced to 32.81 m2/g after activation with phosphoric acid. Batch adsorption experiments revealed that hydrochar produced at 250°C (AC-HTC-250) demonstrated high adsorption capacities of 49.10mg/g for carbamazepine and 14.35mg/g for naproxen, outperforming several conventional adsorbents. Optimal adsorption occurred at pH 4, aligning well with the Langmuir and pseudo-first-order models. The hydrochar showed potential for regeneration and multiple uses, suggesting its applicability in sustainable wastewater treatment. Future research will explore scalability and effectiveness against a broader range of pollutants.

Trash to treasure: A general strategy to prepare high performance graphite block via constructing interfacial transition layers with highly chemically active on recyclable graphite powder

Recently, the cycling of graphite residuum generated in the machining process of isostatic graphite has aroused great interest in both academia and industry as it offers an important solution to reduce the waste of resources and environmental disruption. However, conventional method of simple backfilling of residuum suffers drawbacks of low added-value and environmental pollution owing to the high graphitization degree and low chemical activity of these graphite powders. Herein, we report a general strategy to prepare high-performance graphite block (GBB) while using recyclable graphite powder (RGP) as starting compound via constructing highly chemical active interfacial transition layers (ITLs) on the surface of RGP by impregnated pitch (IP). The ITLs decorated recycled graphite powder (RGP@SC), as reflected in FT-IR, ESR, TG-DTG and EA, contains abundant surface functional groups, free radicals, and heteroatoms which ensures the high chemical activity, thus obviously improving the self-sintering and self-adhesion properties of GBB. As a result, GBB with RGP@SC as the main aggregate display a high homogeneity and mechanical properties. The average open porosity, flexural and compressive strength are determined to 9.90%, 56.60 MPa and 123.50 MPa, respectively, which even outperforms most reported graphite blocks. Impressively, due to the absence of impregnating and multiple calcinating, the process has a short production cycle, which not only saves energy, but also is environmentally friendly. The current work displays benchmark example of the employment of RGP for synthesis of high-performance graphite block.

Chemical Composition of Turmeric (Curcuma longa L.) Ethanol Extract and Its Antimicrobial Activities and Free Radical Scavenging Capacities.

Turmeric (Curcuma longa L.) is a perennial tuberous plant from the genus Curcuma (Zingiberaceae) and has been widely used in foods for thousands of years. The present study examined the ethanol extract of turmeric for its chemical composition, antimicrobial activity, and free radical scavenging properties. UHPLC-MS/MS analysis tentatively identified eight compounds in the turmeric extract. Potential antimicrobial effects of 0.1, 1.0, and 10 mg turmeric equivalents (TE)/mL were evaluated in vitro against a variety of Gram-negative bacteria (i.e., Escherichia coli, Klebsiella pneumoniae, and Pseudomonas sp.) and Gram-positive bacteria (i.e., Enterococcus faecalis, Listeria innocua, and Staphylococcus aureus). Concentrations of 0.1 and 1.0 mg TE/mL inhibited the growth of S. aureus and significantly suppressed that of Pseudomonas sp., E. faecalis, and L. innocua. The growth of all strains, including E. coli, was inhibited by 10 mg TE/mL. Moreover, free radical scavenging capacities were determined using HO●, ABTS●+, and DPPH● (HOSC, ABTS, and RDSC, respectively) radicals. The turmeric ethanol extract had a TPC value of 27.12 mg GAE/g, together with HOSC, RDSC, and ABTS values of 1524.59, 56.38, and 1.70 μmol TE/g, respectively. Our results suggest that turmeric extract has potential applications for use in functional foods to reduce microbial burdens and oxidative stress-related health problems.