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The enzyme tyrosinase plays a key role in the early stages of melanin biosynthesis. This study evaluated the inhibitory activity of anthocyanidin (1) and anthocyanins (2–6) on the catalytic reaction. Of the six derivatives examined, 1–3 showed inhibitory activity with IC50 values of 3.7 ± 0.1, 10.3 ± 1.0, and 41.3 ± 3.2 μM, respectively. Based on enzyme kinetics, 1–3 were confirmed to be competitive inhibitors with Ki values of 2.8, 9.0, and 51.9 μM, respectively. Molecular docking analysis revealed the formation of a binary encounter complex between 1–3 and the tyrosinase catalytic site. Luteolinidin (1) and petunidin 3-O-glucoside (2) may serve as tyrosinase inhibitors to block melanin production.

Purpose: To evaluate the anti-inflammatory effect of methyl-4-(β-D-glucopyranosyloxy)-3-hydroxy-5-methoxybenzoate (comp-1) on immune cells.Methods: Comp-1 was isolated from Sanguisorba officinalis. After treating with comp-1, cell viability and levels of pro-inflammatory cytokines were assessed utilizing MTT assay and ELISA, respectively. Besides, the effects of comp-1 on nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and iNOS were determined using western blotting. Moreover, nitric oxide production was assessed using the Griess reagent.Results: Treatment of dendritic cells (DCs) with CpG DNA upregulated cytokine expression. Comp-1 markedly downregulated the expressions of IL-12 p40, IL-6, and TNF-α, with 50% inhibitory concentrations (IC50) of 1.077 ± 0.04 (p < 0.01), 0.28 ± 0.01 (p < 0.01), and 0.79 ± 0.02 μM (p < 0.01),respectively. Treatment of DCs with CpG DNA upregulated NF-κB and MAPK activation. However, pretreatment of the cells with Comp-1 suppressed CpG DNA-induced NF-κB and MAPK activation. Moreover, comp-1 exhibited a strong anti-inflammatory effect by inhibiting nitric oxide production and iNOS expression.Conclusion: These results reveal that comp-1 has significant anti-inflammatory effect on immune cells. Keywords: Natural compound, Inflammation, Pro-inflammatory cytokine, Toll-like receptor9

Stachys sieboldii MiQ (SSM) is an important food and medicinal herb in Korea, used to improve memory of patients with senile dementia and cardiovascular diseases. However, little information on bio...

The microstructure and mechanical properties of friction stir processed Al−Mg2Si alloys were studied by TEM and EBSD. The results showed that an increase in the tool rotation speed (300−700 r/min) led to a decrease in the defect area (from 10.5 mm2 to zero), whereas the defect area demonstrated the opposite trend (increased to 1.5 mm2 from zero) upon further increasing the rotation speed (700−1200 r/min). The types of defects were transformed from tunnel defects to fusion defects as the rotational speed increased. The coarse Mg2Si dendrites were broken and fine particles (smaller than 10 μm) formed in the weld nugget (WN). The amount of low-angle grain boundaries increased significantly from 57.7% to 83.6%, which was caused by an increase in the content of the deformed structure (from 1.7% to 13.6%). The hardness, ultimate tensile strength (UTS) and elongation were all greatly improved for the weld nugget. The hardness values of the WNs had the following order: R300

An imbalance of osteoclasts and osteoblasts can result in a variety of bone-related diseases, including osteoporosis. Thus, decreasing the activity of osteoclastic bone resorption is the main therapeutic method for treating osteoporosis. 2E-Decene-4, 6-diyn-1-ol-acetate (DDA) is a natural bioactive compound with anti-inflammatory and anti-cancer properties. However, its effects on osteoclastogenesis are unknown. Murine bone marrow-derived macrophages (BMMs) or RAW264.7 cells were treated with DDA, followed by evaluation of cell viability, RANKL-induced osteoclast differentiation, and pit formation assay. Effects of DDA on RANKL-induced phosphorylation of MAPKs were assayed by western blot analysis. Expression of osteoclast-specific genes was examined with reverse transcription-PCR (RT-PCR) and western blot analysis. In this study, DDA significantly inhibited RANKL-induced osteoclast differentiation in RAW264.7 cells as well as in BMMs without cytotoxicity. DDA also strongly blocked the resorbing capacity of BMM on calcium phosphate-coated plates. DDA inhibited RANKL-induced phosphorylation of ERK, JNK and p38 MAPKs, as well as expression of c-Fos and NFATc1, which are essential transcription factors for osteoclastogenesis. In addition, DDA decreased expression levels of osteoclastogenesis-specific genes, including matrix metalloproteinase-9 (MMP-9), tartrate-resistant acid phosphatase (TRAP), and receptor activator of NF-κB (RANK) in RANKL-induced RAW264.7 cells. Collectively, these findings indicated that DDA attenuates RANKL-induced osteoclast formation by suppressing the MAPKs-c-Fos-NFATc1 signalling pathway and osteoclast-specific genes. These results indicate that DDA may be a potential candidate for bone diseases associated with abnormal osteoclast formation and function.

In lipopolysaccharide-induced RAW264.7 cells,This study examined how aster saponin A2 (AS-A2) isolated from AT affects the processes and function of osteoclastogenesis induced by receptor activator of nuclear factor kappa-B ligand (RANKL) in RAW264.7 cells and bone marrow macrophages (BMMs).The cell viability, tartrate-resistant acid phosphatase staining, pit formation assay, polymerase chain reaction, and western blot were carried out to determine the effects of AS-A2 on osteoclastogenesis.In RAW264.7 and BMMs, AS-A2 decreased RANKL-initiated osteoclast differentiation in a concentration-dependent manner. In AS-A2-treated cells, the phosphorylation of ERK1/2, JNK, and p38 protein expression were reduced considerably compared to the control cells. In RAW264.7 cells, AS-A2 suppressed the RANKL-induced activation of osteoclast-related genes. During osteoclast differentiation, AS-A2 suppressed the transcriptional and translational expression of NFATc1 and c-Fos. AS-A2 inhibited osteoclast development, reducing the size of the bone resorption pit area.AS-A2 isolated from AT appears to be a viable therapeutic therapy for osteolytic illnesses, such as osteoporosis, Paget's disease, and osteogenesis imperfecta.

The aerial parts of Tetrastigma hemsleyanum (APTH) have been used as a functional tea in China. The purpose of the current study was to identify the bioactive constituents with inhibitory activity against soluble epoxide hydrolase (sEH) and inducible nitric oxide synthase (iNOS), which are jointly considered potential therapeutic targets for vascular system diseases. In the present study, 39 compounds (1–39) were isolated from the APTH. Among them, compounds 8, 10, 12, 16, 17, 19, and 32 displayed potential activities, with IC50 values ranging from 4.5 to 9.5 µM, respectively, and all in non-competitive inhibition mode. Compounds 5, 10, 12, 19, and 32 displayed potent iNOS inhibitory effects, with IC50 values ranging from 15.6 to 47.3 µM. The results obtained in this work contribute to a better understanding of the pharmacological activities of T. hemsleyanum and its potential application as a functional food.

Flavonoids and triterpenoids were revealed to be the potential inhibitors on soluble epoxide hydrolase (sEH). The aim of this study is to reveal sEH inhibitors from Fuji apples. A flavonoid and three triterpenoids derived from the fruit of Malus domestica were identified as quercetin-3-O-arabinoside (1), ursolic acid (2), corosolic acid (3), and 2-oxopomolic acid (4). They had half-maximal inhibitory concentration of the inhibitors (IC50) values of 39.3 &plusmn, 3.4, 84.5 &plusmn, 9.5, 51.3 &plusmn, 4.9, and 11.4 &plusmn, 2.7 &mu, M, respectively, on sEH. The inhibitors bound to allosteric sites of enzymes in mixed (1) and noncompetitive modes (2&ndash, 4). Molecular simulations were carried out for inhibitors 1 and 4 to calculate the binding force of ligands to receptors. The inhibitors bound to the left (1) and right (4) pockets next to the enzyme&rsquo, s active site. Based on analyses of their molecular docking and dynamics, it was shown that inhibitors 1 and 4 can stably bind sEH at 1 bar and 300 K. Finally, inhibitors 1 and 4 are promising candidates for further studies using cell-based assays and in vivo cardiovascular tests.

Three new compounds, 1-O-trans-p-hydroxycinnamoyl-2′-O-trans-caffeoyl gentiobiose (1), 2S-hydroxy-4-(4-hydroxyphenethoxy)-4-oxobutanoic acid (2), and (3R,4S,5R)-3,4-dihydroxy-5-((R)-1-hydroxyeicosyl) dihydrofuran-2(3 H)-one (3), were isolated from the ethyl acetate fraction of the 90% EtOH extract of Tetrastigma hemsleyanum aerial parts. Their structures were elucidated using ultraviolet, infrared, one- and two-dimensional nuclear magnetic resonance, high-resolution mass spectral data, and conventional chemical methods. The absolute configuration of 3 was determined by circular dichroism. Phenolic components 1 and 2 exhibited weak inhibitory activity against soluble epoxide hydrolase, while compound 3 showed moderate cytotoxicity against the HCT116 cell line.

Sanguisorba officinalis L. (Rosaceae) is a perennial herbaceous plant and its roots have been used as an important astringent medicine in Eastern Asian countries over many thousand years. In this phytochemical research, 23 compounds (1-23) were isolated from the roots of S. officinalis. Their chemical structures were identified by extensive spectroscopic methods, including 1D and 2D NMR experiments. The anti-inflammatory effects of extracts and isolated compounds were investigated by measuring the production of pro-inflammatory cytokine IL-12 p40, IL-6 and TNF-α in LPS-stimulated bone marrow-derived dendritic cell. Compounds 1, 3, 7-8, 11-14 revealed promising anti-inflammatory effects. These results suggested that some phenolic compounds and monoterpenoids from S. officinalis could be potential candidates for anti-inflammatory treatments.

A new 8-prenyl-flavonoid, epimedokoreanoside III, and 11 other flavonoids, were isolated from the aerial parts of Epimedium koreanum Nakai. Their chemical structures were elucidated by nuclear magnetic resonance and mass analyzes. All isolates were evaluated for their soluble epoxide hydrolase and tyrosinase inhibitory activities. Among the isolates, compounds 1, 5, 9, 10, and 12 exerted soluble epoxide hydrolase inhibitory activity in dose-dependent manner, with IC50 values ranging from 26.0 ± 1.2 to 37.6 ± 1.0 µM, whereas compounds 4 and 9 showed potent inhibition of tyrosinase in a dose-dependent manner, having IC50 values of 16.8 ± 2.7 and 8.7 ± 2.7 µM, respectively.

A new self-lubrication concept based on the techniques including of dry grinding and solid lubricating was proposed for green grinding process. And a kind of self-lubrication grinding wheel was designed with solid powder lubricant and centrifugal impeller inside. The self-lubricating was achieved by the blow out of the solid powder lubricant from the inner cavity of the wheel by the centrifugal force to the grinding surface. The experiments were conducted to study the friction and wear properties of the new cylindrical wheel samples manufactured by the proposed concept. The results showed that the flow channel diameters of 1 to 1.5 mm are the best for the blowing out of the solid lubricant to realize the continuous lubricating. After grinding, the surface coating is even, and the sizes of the abrasive particles are relatively uniform with no peeling into blocks. Although there is a certain wear loss of the grinding surface, the wear rate of the particles on the sample wheels is less than that of the traditional grinding wheel. The computational simulation of the self-lubrication wheel is conducted with the RSM method with FLUENT software to analyze the flow field in the wheel cavity of solid lubricant inside, which is meaningful for the study of the motion of the solid lubricant and useful for optimum design of the wheel design to realize the best self-lubricating performance.

Four new aster saponins (1-4) together with five known analogues (5-9) were isolated from Aster tataricus. The chemical structures of 1-4 were elucidated based on spectrometric and spectroscopic analysis and comparison with reported data. The potential anti-inflammatory activities of aster saponins 1-9 were evaluated subsequently by measuring lipopolysaccharide (LPS)-enhanced nitric oxide (NO) formation in murine macrophages. Among these, aster saponin B (6) exhibited the most potent inhibitory activity (IC50: 1.2 μM). Additionally, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein levels were dose-dependently suppressed by 6 in LPS-activated RAW 264.7 cells. Investigation of the anti-inflammatory mechanism indicated that 6 attenuated the phosphorylation and degradation of the inhibitor of NF-κB (IκB), which led to the blocking of NF-κB p65 translocation to the nucleus.

Aster tataricus L.f. is a traditional Eastern Asian herbal medicine used for the relief of cough-related illnesses. In this study, 32 known compounds and two novel monoterpene glycosides were isolated from the roots of A. tataricus. With the aid of reported data, elucidation of the root-extract components was carried out using a multitude of spectroscopic techniques. All isolates were investigated for their ability to inhibit nitric oxide (NO) secretion in lipopolysaccharide-activated RAW264.7 cells. Compound 7 remarkably suppressed NO production with an IC50 value of 8.5 µM. In addition, compound 7 exhibited significant inhibitory activity against the production of inflammatory cytokines (prostaglandin E2, interleukin-6, and interleukin-1 beta) and the expression of inflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) via inhibition of nuclear factor-kappa B activation. Moreover, compound 7 effectively prevented the downstream activation of the mitogen-activated protein kinase signaling pathway by inhibiting phosphorylation of c-Jun N-terminal kinases, extracellular signal-regulated kinases, and p38. These results outline compound 7 as a potential inhibitor for the broad treatment of inflammatory diseases, such as atopic dermatitis, asthma, and various allergies.

The individual parts of Morus alba L. including root bark, branches, leaves, and fruits are used as a cosmetic ingredient in many Asian countries. This study identified several anti-melanogenesis constituents in a 70% ethanol extract of M. alba leaves. The ethyl acetate fraction of the initial ethanol extract decreased the activity of tyrosinase, a key enzyme in the synthetic pathway of melanin. Twelve compounds were isolated from this fraction and their structures were identified based on spectroscopic spectra. Then, the authors investigated the anti-melanogenesis effects of the isolated compounds in B16-F10 mouse melanoma cells. Compounds 3 and 8 significantly inhibited not only melanin production but also intracellular tyrosinase activity in alpha-melanocyte-stimulating-hormone (&alpha, MSH)-induced B16-F10 cells in a dose-dependent manner. These same compounds also inhibited melanogenesis-related protein expression such as microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein-1 (TRP-1). Compound 3 modulated the cAMP-responsive element-binding protein (CREB) and p38 signaling pathways in &alpha, MSH-activated B16-F10 melanoma cells, which resulted in the anti-melanogenesis effects. These results suggest that compound 3, isolated from M. alba leaves, could be used to inhibit melanin production via the regulation of melanogenesis-related protein expression.

Alkaloids 1–10 were isolated from the aerial parts of Tetrastigma hemsleyanum (APTH) and obtained from species of the genus Tetrastigma for the first time. The chemical structures of the isolated compounds were identified by NMR, UV, and MS analyses. Their anti-inflammatory activities were investigated by measuring nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages. Among all the isolates, compounds 6, 7 and 10 showed potent inhibitory activity against LPS-stimulated NO production in RAW264.7 cells (IC50: 31.9, 25.2 and 6.3 μM, respectively). Furthermore, APTH and S-(−)-trolline (10) inhibited induction of inflammatory cytokines or mediators such as interleukin-1β (IL-1β) and inducible nitric oxide synthase (iNOS) via suppression of nuclear factor κB (NF-κB) translocation into the nucleus. In addition, 10 suppressed extracellular signal-regulated protein kinase 1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) phosphorylation in a dose-dependent manner. These results conclusively demonstrated that compound 10 displays anti-inflammatory activity via suppression of NF-κB activation and the ERK-MAPK signaling pathway in LPS-stimulated RAW264.7 cells.

Sanguisorba officinalis L. was well known as a traditional herbal medicine to treat inflammation and allergic skin diseases. The aim of this research was to indentify compounds with anti-allergic inflammatory property. Twenty-five compounds (1-25) were isolated from S. officinalis including two new compounds (1 and 8), and their chemical structures were identified by NMR and ESIMS analysis. Consequently, the anti-allergic inflammatory activities of these isolates were investigated by inhibiting β-hexosaminidase and IL-4 production in PMA/A23187-stimulated RBL-2H3 cells. Compounds 6, 8, 13, 17-18 and 25 significantly inhibited β-hexosaminidase release and IL-4 production. Additionally, compounds 8, 17 and 25 effectively suppressed the activation of NF-κB and NF-κB p65 translocation into the nucleus. Anti-inflammatory effects of isolated compounds were evaluated in LPS-stimulated RAW264.7 macrophages, and they showed dramatic inhibition on LPS-induced overproduction of nitric oxide (NO) and TNF-α. Consistently, the protein levels of iNOS and COX-2 were remarkably decreased by the single compounds 8, 13 and 25. These results showed that compounds 8, 13 and 25 from S. officinalis may have a therapeutic potential for allergic inflammatory diseases.

The aim of this work was to evaluate the main nutrients and their antioxidant properties of a Chinese wild edible fruit, Passiflora foetida, collected from the ecoregion of Hainan province, China. The analytical results revealed that P. foetida fruits were rich in amino acids (1097 mg/100 g in total), minerals (595.75 mg/100 g in total), and unsaturated fatty acids (74.18 g/100 g in total fat). The lyophilized powder of edible portion contained the higher polyphenols content than the inedible portion powder. The UPLC-Q-TOF-MSE analysis of the extractable and non-extractable phenolics indicated the presence of 65 compounds including 39 free phenolics, 14 insoluble-glycoside-phenolics, and 22 insoluble-ester-phenolics. In addition, the non-extractable phenolics obtained by alkali hydrolysis showed significant antioxidant activities by/through DPPH and ABTS radical scavenging. These findings of P. foetida fruits, for the first time, suggest that these polyphenol-rich fruits may have potential nutraceutical efficacies.

Sanguisorba officinalis L. is a traditional herbal medicine, which is prevailingly applied to cure hemorrhoids, wounds and ulcers in Eastern Asian countries. The purpose of this study was to investigate the antibacterial and soluble epoxide hydrolase (sEH) inhibitory effects of the extracts and components from S. officinalis. The methanol extract was divided into ethyl acetate (EtOAc), n-butanol (n-BuOH), and water layers. In our screening procedure, the EtOAc and n-BuOH extracts and compounds (1–2) remarkably suppressed the growth of V. vulnificus in a dose-dependent manner. In addition, the EtOAc extract and compound 1 exhibited significant inhibitory effect on the V. vulnificus induced cytotoxicity on HeLa cells. Furthermore, compound 4 displayed an inhibition against sEH with an IC50 value of 7.0 ± 0.5 μM. A kinetic analysis demonstrated that the inhibitory effect of compound 4 was a mixed type, with an inhibitory constant (Ki) 0.22 ± 0.0 μM.

In this study, 21 compounds were isolated from the aerial parts of Epimedium koreanum Nakai, including 6 phenols (1–5 and 10), 4 lignans (6–9) and 11 flavonoids (11–21). The chemical structures of those isolates were established after extensive one-and two-dimensional nuclear magnetic resonance and mass spectroscopy analyses. This is the first report of compounds 2, 3, 4 and 9 in E. koreanum and of compounds 5 and 7 in the family Berberidaceae. The chemotaxonomic significance of the isolated compounds is discussed.

The Pb–Ag–Ca alloy anode with surface passivation was applied in industrial production of zinc electrowinning. The application situation was investigated by detection and tracking more than 3 months. The results were analyzed by comparison with the data acquired from the production using the reference anodes without surface treatment. The results showed that using the anode with surface passivation can increase zinc yield, reduce Pb content in zinc product, prolong the anode life by improving the corrosion resistance, and then reduce the production costs.

In order to investigate the density anomaly of vitreous silica in the medium-or long-range order, different models were made to study the atomic configuration revolution in thermal history by molecular dynamics. The void structures have been studied through analyzing the best model that is carefully selected. The principle of void size distribution revolution at elevated temperatures was used to explain the density anomaly of the vitreous silica. The simulation results showed that when the temperature is low, the void radius increases with the temperature rising. After 2000 K, large void structures are destroyed, filled, or separated into small radius voids. In the range from 2000 K to 2400 K, large void structures decrease faster exceeding the bond extension on thermal expansion contribution, this should be the root cause of negative thermal expansion behavior for vitreous silica. When the temperature is greater than 2400 K, with the temperature rising, the normal thermal expansion is recovered gradually because number of large voids has been reduced and their destroying cannot eliminate the contribution to expansion of bond extension. Therefore, the negative thermal expansion of vitreous silica could be described by the revolution of void structures in the medium-or long-range clearly, and is mainly influenced by the existence and change of larger voids.

In order to explore the energy saving measures in gibbsite crystallization process for alumina production by Bayer method, industrial experiment was carried out to investigate the solid dispersion in a slight agitation seed precipitation tank for gibbsite crystallization. The experimental results showed that little difference of solid concentration, only 48.19 g·l-1is found in the range from 5 meters depth to the tank bottom, which is the most zone of the tank, and there is a somewhat large difference in the top 5 meters zone near the surface that is about 149.66 g·l-1. Therefore, under the condition of slight agitation, solid content would not concentrate to the tank bottom completely with the normal work flow. It is suggested that the work of production would not be interrupted in less agitation than before, and the electrical energy saving rate is about 34%. The effects of reduced agitation on the yield and the quality of gibbsite crystallization should be studied carefully in subsequent works.

NiTi shape memory alloy was potentiostatically anodized in a molybdate electrolyte containing ammoniac ion to form a thick and uniform oxide layer. The oxide layer was characterized by SEM, XRD, EPMA, XPS and potentiodynamic polarization test. It was found that the as-prepared coating is a thick (approx. 40 μm), smooth and dense oxide layer, and is free of cracks and porous defects. Moreover, the surface analyses revealed that the anodic oxidation at 60 mV potential (SCE) reduces significantly the proportion of Ni in the outmost surface layer, and the atomic ratio of Ti and Ni elements is raised from 1:1 to 9.7:1. The as-prepared coating was primarily composed of noncrystalline TiO2 on the outermost surface with a small quantity of Ni (OH)2. Potentiodynamic polarization tests in Fusayama artificial saliva pH 6.2 demonstrated that the oxide layer presents a significant increase in breakdown potential due to titanium enrichment.

In order to explore the feasibility of remove agitation in gibbsite precipitation process, computational fluid dynamics method was carried out to study the flow field of sodium aluminate solution slurry in an unagitated precipitation tank. The solid content distribution is investigated by volume fraction of solid phase. The simulation results showed that little difference of solid content is found in the range between the tank bottom and the height position of 25 meters, which is the most zone of the tank, and there is a somewhat large difference in the top 5 meters zone, where the stratification occurs. With the inlet velocity increases, the zone of stratification shrinks to near the tank surface, which makes the solid content distribution in the whole tank seem uniform much more. Therefore, without agitation, the solid content would not concentrate to tank bottom completely in the normal work flow.

The research on the pressure and velocity characteristics of the fuze inlet airflow as a second environmental force was done. The pressure difference under different airflow velocity between two pressure openings set up at fuze inlet tube throat and expansion section was obtained by CFD simulation. Through the simulation and analysis on ballistic characteristics and fluid pressure characteristics , the time characteristics of pressure difference of the pressure openings were summarized. Furthermore,the quantitative analysis result of the output signal and the feasibility of the pressure difference as an information source for fuse arming are put forward.