The different toxicological effects and removal efficiencies of norfloxacin and sulfadiazine in culturing Arthrospira (Spirulina) platensis.

Norfloxacin (NFX) and sulfadiazine (SDZ) are two widely used antibiotics belonging to fluoroquinolone and sulfonamide groups, respectively, and have become the commonly detected micropollutants in aquatic environments. However, only few works have been conducted to investigate the highly probable inhibition of these antibiotic pollutants to Arthrospira platensis, which is an important species of cyanobacteria that is one of primary producers in aquatic ecosystems and should be remarkably sensitive to environmental pollutants due to its prokaryotic characteristics. Hence, the toxicological effects and removal efficiencies of NFX and SDZ in culturing A. platensis were studied by analyzing the biomass growth, photosynthetic pigments, primary biocomponents, and antibiotics concentration. The corresponding variations of these characteristics showed the higher sensitivity of A. platensis to NFX than to SDZ, indicating the specifically targeted effect of NFX on A. platensis, which could be confirmed in silico by the higher binding affinity of NFX with the critical enzyme. The obtained results illustrated the roles of NFX and SDZ on the growth of A. platensis, thus providing the great support in employing A. platensis to reduce hazards from contaminated water and recover biomass resources.

Ecotoxicological effect of enrofloxacin on Spirulina platensis and the corresponding detoxification mechanism.

Enrofloxacin is a widely used antibiotic targeting DNA gyrase and has become the commonly detected micropollutant in aquatic environments. Thus, the potential toxicity of enrofloxacin to Spirulina platensis which is a kind of prokaryote similar to Gram-negative bacteria has been hypothesized. However, little is known about the toxicity and degradation mechanism of enrofloxacin during the growth process of Spirulina platensis. Herein, the biomass accumulation of Spirulina platensis was stimulated to 115% of the control group by 0.1 mg L-1 enrofloxacin (10th day), which could be removed probably through the metabolism. Further increasing the enrofloxacin level to 5.0 mg L-1 almost inhibited the growth and remediation ability of Spirulina platensis for 35 days. Environmental stress also caused the variations of photosynthetic pigments (chlorophyll a and carotenoids) and primary biocomponents (proteins, lipids, and carbohydrates), reflecting the adaptation of Spirulina platensis for handling the negative effects of enrofloxacin. The detoxification mechanism was studied by identifying the degradation products of enrofloxacin, suggesting the occurrence of dealkylation and oxidation reactions primarily at the piperazine group. The decreased antimicrobial activity was confirmed by the reduced binding affinity of degradation products with enzymes. The obtained results could help us understand the role of enrofloxacin in the growth of Spirulina platensis, thus providing great support for employing Spirulina platensis in risk assessment and hazard reduction.

A Novel Chemiluminescent Method for Efficient Evaluation of Heterogeneous Fenton Catalysts Using Cigarette Tar.

The evaluation of the catalytic capacity of catalysts is indispensable research, as catalytic capacity is a crucial factor to dictate the efficiency of heterogeneous Fenton catalysis. Herein, we obtained cigarette tar-methanol extracts (CTME) by applying methanol to cigarette tar and found that CTME could cause CL reactions with Fe2+/H2O2 systems in acidic, neutral, and alkaline media. The CL spectrum experiment indicated that the emission wavelengths of the CTME CL reaction with Fe2+/H2O2 systems were about 490 nm, 535 nm, and 590 nm. Quenching experiments confirmed that hydroxyl radicals (•OH) were responsible for the CL reaction for CTME. Then the CL property of CTME was applied in-situ to rapidly determine the amounts of •OH in tetrachloro-1,4-benzoquinone (TCBQ)/H2O2 system in acidic, neutral and alkaline media, and the CL intensities correlated the best (R2 = 0.99) with TCBQ concentrations. To demonstrate the utility of the CTME CL method, the catalytic capacity of different types and concentrations of catalysts in heterogeneous Fenton catalysis were examined. It was found that the order of CL intensities was consistent with the order of degradation efficiencies of Rhodamine B, indicating that this method could distinguish the catalytic capacity of catalysts. The CTME CL method could provide a convenient tool for the efficient evaluation of the catalytic capacity of catalysts in heterogeneous Fenton catalysis.

Neuroprotective and Anti-Inflammatory Effect of Pterostilbene Against Cerebral Ischemia/Reperfusion Injury via Suppression of COX-2.

Background: The incidence of cerebral ischemia disease leading cause of death in human population worldwide. Treatment of cerebral ischemia remains a clinical challenge for researchers and mechanisms of cerebral ischemia remain unknown. During the cerebral ischemia, inflammatory reaction and oxidative stress plays an important role. The current investigation scrutinized the neuroprotective and anti-inflammatory role of pterostilbene against cerebral ischemia in middle cerebral artery occlusion (MCAO) rodent model and explore the underlying mechanism. Methods: The rats were divided into following groups viz., normal, sham, MCAO and MCAO + pterostilbene (25 mg/kg) group, respectively. The groups received the oral administration of pterostilbene for 30 days followed by MCAO induction. The neurological score, brain water content, infarct volume and Evan blue leakage were estimated. Hepatic, renal, heart, inflammatory cytokines and inflammatory mediators were estimated. Results: Pterostilbene treatment significantly (p < 0.001) improved the body weight and suppressed the glucose level and brain weight. Pterostilbene significantly (p < 0.001) reduced the hepatic, renal and heart parameters. Pterostilbene significantly (p < 0.001) decreased the level of glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and decreased the level of malonaldehyde (MDA), 8-Hydroxy-2'-deoxyguanosine (8-OHdG). Pterostilbene significantly (p < 0.001) inflammatory cytokines and inflammatory parameters such as cyclooxygenase-2 (COX-2), inducible nitric oxidase synthase (iNOS) and prostaglandin (PGE2). Pterostilbene significantly (p < 0.001) down-regulated the level of metalloproteinases (MMP) such as MMP-2 and MMP-9. Pterostilbene suppressed the cellular swelling, cellular disintegration, macrophage infiltration, monocyte infiltration and polymorphonuclear leucocyte degranulation in the brain. Conclusion: In conclusion, Pterostilbene exhibited the neuroprotective effect against cerebral ischemia in rats via anti-inflammatory mechanism.

FGF21 promotes wound healing of rat brain microvascular endothelial cells through facilitating TNF-α-mediated VEGFA and ERK1/2 signaling pathway.

BACKGROUND: Wound healing is an essential physiological process in recovery after microsurgery. OBJECTIVES: To further understand the functions of fibroblast growth factor 21 (FGF21), the roles of this factor were examined and its correlations with inflammation, vascular endothelial growth factor A (VEGFA) and ERK1/2 signaling pathway activation were analyzed. MATERIAL AND METHODS: Rat brain microvascular endothelial cells (RBMECs) were treated with interleukin (IL)-1ß and used for the experiments. Cell Counting Kit-8 (CCK-8) was used to detect the cell viability of RBMECs after treatment with IL-1ß (1 ng/mL) and FGF21 or VEGFA overexpression, while changes in apoptosis were measured through flow cytometry. Migration was checked through the scratch test. FGF21 and VEGFA RNA expression was assessed using reverse-transcription quantitative polymerase chain reaction (RT-qPCR), which was also used to examine RNA expression of Bcl-2, Bax and caspase-3. After IL-1ß treatment and FGF21 overexpression, tumor necrosis factor alpha (TNF-α) and tumor growth factor ß1 (TGF-ß1) proteins level were observed with enzyme-linked immunosorbent assay (ELISA), which was also applied to check the expression of ERK1/2 after overexpression of FGF21 and VEGFA. PD98059 (50 µM), an ERK1/2 inhibitor, was used to examine the roles of ERK1/2 in regulating cell viability and apoptosis. RESULTS: The IL-1ß treatment significantly decreased the viability of RBMECs and TGF-ß1, but promoted cell apoptosis and TNF-α expression. FGF21 was downregulated by IL-1ß treatment but its overexpression enhanced the viability of RBMECs and TGF-ß1 and ERK1/2 protein levels, and attenuated cell apoptosis and TNF-α. Upregulated TNF-α restrained cell viability and apoptosis of RBMECs after FGF21 overexpression, and its upregulation not only suppressed FGF21, but also VEGFA. Moreover, VEGFA suppression by TNF-α increased cell viability and ERK1/2 protein levels, and suppressed the apoptosis of RBMECs through its upregulation. However, PD98059 obstructed the functions of FGF21 and VEGFA. CONCLUSIONS: FGF21 promoted the cell viability of RBMECs through upregulating TNF-α-mediated VEGFA and ERK1/2 signaling.

Identification and elimination of false positives in electrochemical nitrogen reduction studies.

Ammonia is of emerging interest as a liquefied, renewable-energy-sourced energy carrier for global use in the future. Electrochemical reduction of N2 (NRR) is widely recognised as an alternative to the traditional Haber-Bosch production process for ammonia. However, though the challenges of NRR experiments have become better understood, the reported rates are often too low to be convincing that reduction of the highly unreactive N2 molecule has actually been achieved. This perspective critically reassesses a wide range of the NRR reports, describes experimental case studies of potential origins of false-positives, and presents an updated, simplified experimental protocol dealing with the recently emerging issues.

Eliminating imidacloprid and its toxicity by permanganate via highly selective partial oxidation.

Imidacloprid is a widely used neonicotinoid insecticide worldwide, and has attracted great concerns due to its potential threat to human and environment. Much effort was thus spent on developing the effective way for removing imidacloprid from water, but might also produce various degradation products with unknown risks. The hypothesis was then proposed that permanganate oxidation was probably the appropriate tool for eliminating imidacloprid and its toxicity through selective oxidation of specific groups. To that end, we studied the kinetics of permanganate/imidacloprid reaction by considering the effects of pH (5.0-9.0), temperature (15-35 °C), ionization strength (0.05-0.20 M), typical anions (Cl-, Br-, I-) and humic acid. Based on the identified products from mass spectrometer, the main reaction pathway was found to be the hydroxylation of C-H bond at imidazole ring, leading to the decreased toxicity evaluated by ECOSAR program. Our results demonstrate that permanganate oxidation should be a very promising technique for controlling imidacloprid contamination by effective detoxification through highly selective partial oxidation. Moreover, this study has also paved the way toward applying permanganate oxidation for in situ chemical remediation of imidacloprid, though the corresponding standards need to be established in advance.

Therapeutic evidence of umbilical cord-derived mesenchymal stem cell transplantation for cerebral palsy: a randomized, controlled trial.

BACKGROUND: Cerebral palsy (CP) is a syndrome of childhood movement and posture disorders. Clinical evidence is still limited and sometimes inconclusive about the benefits of human umbilical cord mesenchymal stem cells (hUC-MSCs) for CP. We conducted a randomized trial to evaluate the safety and efficacy of hUC-MSC transplantation concomitant with rehabilitation in patients with CP. METHODS: Eligible patients were allocated into the hUC-MSC group and control group. In addition to rehabilitation, the patients in the hUC-MSC group received four transfusions of hUC-MSCs intravenously, while the control group received a placebo. Adverse events (AEs) were collected for safety evaluation in the 12-month follow-up phase. Primary endpoints were assessed as activities of daily living (ADL), comprehensive function assessment (CFA), and gross motor function measure (GMFM) scales. In addition, cerebral metabolic activity was detected by 18F-FDG-PET/CT to explore the possible mechanism of the therapeutic effects. Primary endpoint data were analyzed by ANOVA using SPSS version 20.0. RESULTS: Forty patients were enrolled, and 1 patient withdrew informed consent. Therefore, 39 patients received treatments and completed the scheduled assessments. No significant difference was shown between the 2 groups in AE incidence. Additionally, significant improvements in ADL, CFA, and GMFM were observed in the hUC-MSC group compared with the control group. In addition, the standard uptake value of 18F-FDG was markedly increased in 3 out of 5 patients from the hUC-MSC group at 12 months after transplantation. CONCLUSIONS: Our clinical data showed that hUC-MSC transplantation was safe and effective at improving the gross motor and comprehensive function of children with CP when combined with rehabilitation. Recovery of cerebral metabolic activity might play an essential role in the improvements in brain function in patients with CP. The therapeutic window, transfusion route, and dosage in our study were considerable for reference in clinical application. TRIAL REGISTRATION: Chictr.org.cn, ChiCTR1800016554. Registered 08 June 2018-retrospectively registered. The public title was "Randomized trial of umbilical cord-derived mesenchymal stem cells for cerebral palsy."

AMPKα1 overexpression improves postoperative cognitive dysfunction in aged rats through AMPK-Sirt1 and autophagy signaling.

Postoperative cognitive dysfunction (POCD) is a common complication in elderly patients who undergo surgery involving anesthesia. Its underlying mechanisms remain unclear. Autophagy plays an important role in the damage and repair of the nervous system and is associated with the development of POCD. Using a rat model, adenosine monophosphate-activated protein kinase α1 (AMPKα1), an important autophagy regulator, was found to be significantly downregulated in rats with POCD that was induced by sevoflurane anesthesia or by appendectomy. Overexpression of AMPKα1-ameliorated POCD, as indicated by decreased escape latencies and increased target quadrant swimming times, swimming distances, and platform crossing times during Morris water maze tests. AMPKα1 overexpression activated autophagy signals by increasing the expression of light chain 3 II (LC3-II) and Beclin1 and decreasing the expression of p62 in the hippocampus of rats with POCD. Moreover, blocking autophagy by 3-methyladenine partly attenuated AMPKα1-mediated POCD improvement. Furthermore, overexpression of AMPKα1 could upregulate the expression of p-AMPK and Sirt1 in the hippocampus of rats with POCD. Intriguingly, inhibiting AMPK signals via Compound C effectively attenuated AMPKα1-mediated POCD improvement, concomitant with the downregulation of p-AMPK, Sirt1, LC3-II, and Beclin1 and the upregulation of p62. We thus concluded that overexpression of AMPKα1 can improve POCD via the AMPK-Sirt1 and autophagy signaling pathway.

A formation model of superoxide radicals photogenerated in nano-TiO2 suspensions.

A formation model of O2˙- produced in TiO2 photocatalysis was established, and then a custom built continuous flow chemiluminescence (CFCL) system was used to confirm the model's reliability by monitoring the O2˙- formation process. This model may give deeper insights into O2˙- formation for TiO2 and other photocatalysts.

Energy-Efficient Nitrogen Reduction to Ammonia at Low Overpotential in Aqueous Electrolyte under Ambient Conditions.

The electrochemical nitrogen reduction reaction (NRR) under ambient conditions is a promising alternative to the traditional energy-intensive Haber-Bosch process to produce NH3 . The challenge is to achieve a sufficient energy efficiency, yield rate, and selectivity to make the process practical. Here, we demonstrate that Ru nanoparticles (NPs) enable NRR in 0.01 m HCl aqueous solution at very high energy efficiency, that is, very low overpotentials. Remarkably, the NRR occurs at a potential close to or even above the H+ /H2 reversible potential, significantly enhancing the NRR selectivity versus the production of H2 . NH3 yield rates as high as ≈5.5 mg h-1 m-2 at 20 °C and 21.4 mg h-1 m-2 at 60 °C were achieved at a redox potential (E) of -100 mV versus the reversible hydrogen electrode (RHE), whereas a highest Faradaic efficiency (FE) of ≈5.4 % is achievable at E=+10 mV vs. RHE. This work demonstrates the potential use of Ru NPs as an efficient catalyst for NRR at ambient conditions. This ability to catalyze NRR at potentials near or above RHE is imperative in improving the NRR selectivity towards a practical process as well as rendering the H2 viable as byproduct. Density functional theory calculations of the mechanism suggest that the efficient NRR process occurring on these predominantly Ru (0 0 1) surfaces is catalyzed by a dissociative mechanism.

Direct evidence for surface long-lived superoxide radicals photo-generated in TiO2 and other metal oxide suspensions.

Heterogeneous catalytic reactions usually proceed at the surfaces of materials, where many intermediates, such as free radicals, usually were believed to be short-lived. Herein, surface long-lived superoxide radicals (O2˙-) were identified in UV-irradiated aqueous suspensions of TiO2 and other metal oxide nanoparticles using an online chemiluminescence system. From the decay dynamics process of O2˙-, a long-lived O2˙- radical was observed on anatase TiO2 at pH = 12. After separation of the photo-excited suspension via filtration, CL was detected from the particles but not the filtrate, thus confirming O2˙- surface adsorption. The unusual stability of O2˙- was also verified using density functional theory (DFT) calculations. The lifetimes of the radicals were estimated on the different kinds of semiconductor surface according to the decay dynamics curves, and followed the order: TiO2 > ZnO > SnO2 > CeO2 > Fe2O3. Furthermore, the function of surface long-lived O2˙- in TiO2 suspensions with regards to photochemical conversion was investigated using NBT as a chemical model; it was found that half of the molecules were reduced by the surface-adsorbed O2˙-. The finding of surface-stabilized, long-lived superoxide radicals may have important implications in relation to the chemistry, biology and toxicology of these radicals.

A new method for hydroxyl radical detection by chemiluminescence of flue-cured tobacco extracts.

Chemiluminescence (CL) reactions usually take place in a severely restricted pH regime, thereby confining their application in media at different pH. In this paper, the CL behavior of tobacco-methanol extract (TME) was explored. Surprisingly, TME exhibited CL behavior upon mixing with Fe2+/H2O2, HRP/H2O2 and gold nanoparticles/H2O2 oxidation systems, i.e., in acidic, neutral and alkaline solution respectively. Addition of different reactive oxygen species scavengers verified that the hydroxyl radical (OH) triggers TME CL reactions. Then, the CL behavior of TME was applied to determine OH in tetrachloro-1,4-benzoquinone (TCBQ)/H2O2 system in acidic, neutral and alkaline solutions. CL intensity correlated most strongly (R2 = 0.99) with TCBQ concentration, which was used as a means to indirectly denote OH concentration. This implies that OH could be determined by a TME CL method in a semi-quantitative way regardless of pH value. Therefore, the TME CL method may be a promising method for OH determination in various OH-generating systems.

[Application of MRI in diagnosis of transient dislocation of patella].

OBJECTIVE: To explore the diagnostic value of MRI in the transient dislocation of the patella. METHODS: The DR and MRI data of 35 patients with acute patellar transient dislocation from January 2015 to December 2017 were retrospectively analyzed, including 12 males and 23 females, ranging in age from 10 to 23 years old, with an average of 17 years old. The differences between DR and MRI diagnosis and surgical or discharge diagnosis were compared, and the difference between them in diagnosis of knee anatomical position, bone injury, signs and soft tissue injury were compared. The R statistical software WiLcoxon signed rank test (WiLcoxon signed rank test) was used for statistical analysis. RESULTS: All 35 MRI findings were completely consistent with postoperative or discharge diagnosis. According to MRI, 7 cases of high patella and 7 cases of patella subluxation were diagnosed. According to DR, 7 cases of high patella and 0 cases of patella subluxation were diagnosed. Fourteen dislocations were diagnosed by MRI and 7 dislocations were diagnosed by DR. There was statistically significant difference between the two methods in the diagnosis of abnormal position of patella(v=10, P<0.05). Total 112 cases of bone injuries were diagnosed by MRI, and 0 was diagnosed by DR. There was statistically significant difference between the two methods in the diagnosis of bone injuries(v=16, P<0.05). Total 43 cases of soft tissue injuries were diagnosed by MRI, and 0 was diagnosed by DR. There was statistically significant difference between the two methods in the diagnosis of soft tissue injuries (v=21, P<0.05). Total 35 cases of hydrops of the knee joint were diagnosed by MRI, and 30 were diagnosed by DR. There was statistically significant difference between the two methods in the diagnosis of hydrops of the knee joint(v=32, P>0.05). CONCLUSIONS: MRI is superior to DR in the diagnosis of acute temporal bone dislocation. MRI should be used as the first choice for imaging diagnosis of acute temporal bone dislocation. It can avoid missed diagnosis and misdiagnosis.

Ionic liquid electrolytes supporting high energy density in sodium-ion batteries based on sodium vanadium phosphate composites.

Sodium-ion batteries (SIBs) are widely considered as alternative, sustainable, and cost-effective energy storage devices for large-scale energy storage applications. In this work, an easily fabricated sodium vanadium phosphate-carbon composite (NVP@C) cathode material shows a good rate capability, and long cycle life (89% capacity retention after 5000 cycles at a rate of 10C) with an ionic liquid electrolyte for room temperature sodium metal batteries. The electrochemical performance of a full-cell sodium ion battery with NVP@C and hard carbon electrodes was also investigated at room temperature with an ionic liquid electrolyte. The battery exhibited 368 W h kg-1 energy density and 75% capacity retention after 100 cycles, outperforming the organic electrolyte-based devices.

Sirt3-Mediated Autophagy Contributes to Resveratrol-Induced Protection against ER Stress in HT22 Cells.

Endoplasmic reticulum (ER) stress occurring in stringent conditions is critically involved in neuronal survival and death. Resveratrol is a non-flavonoid polyphenol that has neuroprotective effects against many neurological disorders. Here, we investigated the potential protective effects of resveratrol in an in vitro ER stress model mimicked by tunicamycin (TM) treatment in neuronal HT22 cells. We found that TM dose-dependently decreased cell viability and increased apoptosis, which were both significantly attenuated by resveratrol treatment. Resveratrol markedly reduced the expression or activation of ER stress-associated factors, including GRP78, CHOP, and caspase-12. The results of immunocytochemistry and western blot showed that resveratrol promoted autophagy in TM-treated cells, as evidenced by increased LC3II puncta number, bcelin1 expression and LC3II/LC3I ratio. Pretreatment with the autophagy inhibitor chloroquine could reduce the protective effects of resveratrol. In addition, the expression of Sirt3 protein and its downstream enzyme activities were significantly increased in resveratrol-treated HT22 cells. To confirm the involvement of Sirt3-mediated mechanisms, siRNA transfection was used to knockdown Sirt3 expression in vitro. The results showed that downregulation of Sirt3 could partially prevented the autophagy and protection induced by resveratrol after TM treatment. Our study demonstrates a pivotal role of Sirt3-mediated autophagy in mediating resveratrol-induced protection against ER stress in vitro, and suggests the therapeutic values of resveratrol in ER stress-associated neuronal injury conditions.

Dynamic Tracking of Highly Toxic Intermediates in Photocatalytic Degradation of Pentachlorophenol by Continuous Flow Chemiluminescence.

Photocatalytic degradation is a powerful technique for the decomposition of pollutants. However, toxic intermediates might be generated which have become a great concern recently. In the present work, a continuous flow chemiluminescence (CFCL) method was developed for dynamic monitoring of toxic intermediates generated in the photocatalytic degradation of pentachlorophenol (PCP). Among the main intermediates, tetrachloro-1,4-benzoquinone (TCBQ) and trichlorohydroxy-1,4-benzoquinone (OH-TrCBQ) showed higher or similar toxicity to PCP. As both TCBQ and OH-TrCBQ can produce chemiluminescence (CL) in the presence of H2O2, a CFCL system was established for the dynamic tracking of the two toxic intermediates. A PCP/TiO2 suspension was irradiated in a photoreactor, pumped continuously into a detection cell, and mixed with H2O2 to produce CL. The time-dependent CL response displayed two distinctive peaks at pH 7, which were attributed to the generation of OH-TrCBQ and TCBQ, respectively, by comparing with their changes measured by high-performance liquid chromatography (HPLC). Furthermore, the CL response curve of PCP/TiO2 suspension showed a pattern very similar to their bacteria inhibition. Therefore, the CFCL could be used as a simple and low-cost method for online monitoring of TCBQ and OH-TrCBQ to ensure complete removal of not only PCP but also highly toxic degradation intermediates.

Treatment mechanism of matrine in combination with irinotecan for colon cancer.

The inhibitory effect of matrine (MA) was studied in combination with irinotecan (CPT-11) on proliferation of human colon carcinoma cell line HT29. We also explored the mechanism of cell apoptosis induction in HT29. HT29 cells were treated with different concentrations of MA and CPT-11 alone and in combination. The growth inhibition in HT29 cells was evaluated using MTT assay. Apoptosis was detected using AV-PI double staining flow cytometry. Transmission electron microscopy was used to detect structural changes in cells. Topoisomerase (TOPO) I, Bax and Caspase-3 expression levels were evaluated using western blot analysis. MA and CPT-11 alone and in combination, inhibited the proliferation of HT29 cells, whereas the combination treatment exhibited higher inhibitory effect (P<0.01). This suggests the existence of synergistic cytotoxicity. Compared with each treatment alone, the combination treatment caused more significant damage to cell structure, and caused a significantly higher apoptosis rate (P<0.01). Additionally, the combination treatment increased TOPO I, Bax and Caspase-3 expression levels (P<0.01). In conclusion, MA in combination with CPT-11 synergistically inhibited HT29 cell proliferation and induced apoptosis in these cells. The mechanism may be related to upregulation of the TOPO I, Bax and Caspase-3 protein expression.

Identification of Ginger (Zingiber officinale Roscoe) Volatiles and Localization of Aroma-Active Constituents by GC-Olfactometry.

For the characterization of chemical components contributing to the aroma of ginger, which could benefit the development of deep-processed ginger products, volatile extracts were isolated by a combination of direct solvent extraction-solvent-assisted flavor evaporation and static headspace analysis. Aroma-impact components were identified by gas chromatography-olfactometry-mass spectrometry, and the most potent odorants were further screened by aroma extract dilution analysis (AEDA) and static headspace dilution analysis (SHDA). The AEDA results revealed that geranial, eucalyptol, ß-linalool, and bornyl acetate were the most potent odorants, exhibiting the highest flavor dilution factor (FD factor) of 2187. SHDA indicated that the predominant headspace odorants were α-pinene and eucalyptol. In addition, odorants exhibiting a high FD factor in SHDA were estimated to be potent aroma contributors in AEDA. The predominant odorants were found to be monoterpenes and sesquiterpenes, as along with their oxygenated derivatives, providing minty, lemon-like, herbal, and woody aromas. On the other hand, three highly volatile compounds detected by SHDA were not detected by AEDA, whereas 34 high-polarity, low-volatility compounds were identified only by AEDA, demonstrating the complementary natures of SHDA and AEDA and the necessity of utilizing both techniques to accurately characterize the aroma of ginger.

Light-induced efficient molecular oxygen activation on a Cu(II)-grafted TiO2/graphene photocatalyst for phenol degradation.

An efficient photocatalytic process involves two closely related steps: charge separation and the subsequent surface redox reaction. Herein, a ternary hybrid photocatalytic system was designed and fabricated by anchoring Cu(II) clusters onto a TiO2/reduced graphene oxide (RGO) composite. Microscopic and spectroscopic characterization revealed that both TiO2 nanoparticles and Cu(II) clusters were highly dispersed on a graphene sheet with intimate interfacial contact. Compared with pristine TiO2, the TiO2/RGO/Cu(II) composite yielded an almost 3-fold enhancement in the photodegradation rate toward phenol degradation under UV irradiation. Electron spin resonance (ESR) spectra and electrochemical measurements demonstrated that the improved photocatalytic activity of this ternary system benefitted from the synergetic effect between RGO and Cu(II), which facilitates the interfacial charge transfer and simultaneously achieves in situ generation of H2O2 via two-electron reduction of O2. These results highlight the importance to harmonize the charge separation and surface reaction process in achieving high photocatalytic efficiency for practical application.