Triple Templates Directed Synthesis of Nitrogen-Doped Hierarchically Porous Carbons from Pyridine Rich Monomer as Efficient and Reversible SO2 Adsorbents.

Herein, a variety of 2,6-diaminopyridine (DAP) derived nitrogen-doped hierarchically porous carbon (DAP-NHPC-T) prepared from carbonization-induced structure transformation of DAP-Zn-SiO2-P123 nanocomposites are reported, which are facilely prepared from solvent-free co-assembly of block copolymer templates P123 with pyridine-rich monomer of DAP, Zn(NO3)2 and tetramethoxysilane. In the pyrolysis process, P123 and SiO2 templates promote the formation of mesoporous and supermicroporous structures in the DAP-NHPC-T, while high-temperature volatilization of Zn contributed to generation of micropores. The DAP-NHPC-T possess large BET surface areas (≈956-1126 m2 g-1), hierarchical porosity with micro-supermicro-mesoporous feature and high nitrogen contents (≈10.44-5.99 at%) with tunable density of pyridine-based nitrogen sites (≈5.99-3.32 at%), exhibiting good accessibility and reinforced interaction with SO2. Consequently, the DAP-NHPC-T show high SO2 capacity (14.7 mmol g-1, 25 °C and 1.0 bar) and SO2/CO2/N2 IAST selectivities, extraordinary dynamic breakthrough separation efficiency and cycling stability, far beyond any other reported nitrogen-doped metal-free carbon. As verified by in situ spectroscopy and theoretical calculations, the pyridine-based nitrogen sites of the DAP-NHPC-T boost SO2 adsorption via the unique charge transfer, the adsorption mechanism and reaction model have been finally clarified.

Interfacial Engineering Boosting the Activity and Stability of MIL-53(Fe) toward Electrocatalytic Nitrogen Reduction.

The electrochemical nitrogen reduction reaction (eNRR) has emerged as a promising strategy for green ammonia synthesis. However, it suffers unsatisfactory reaction performance owing to the low aqueous solubility of N2 in aqueous solution, the high dissociation energy of N≡N, and the unavoidable competing hydrogen evolution reaction (HER). Herein, a MIL-53(Fe)@TiO2 catalyst is designed and synthesized for highly efficient eNRR. Relative to simple MIL-53(Fe), MIL-53(Fe)@TiO2 achieves a 2-fold enhancement in the Faradaic efficiency (FE) with an improved ammonia yield rate by 76.5% at -0.1 V versus reversible hydrogen electrode (RHE). After four cycles of electrocatalysis, MIL-53(Fe)@TiO2 can maintain a good catalytic activity, while MIL-53(Fe) exhibits a significant decrease in the NH3 yield rate and FE by 79.8 and 82.3%, respectively. Benefiting from the synergetic effect between TiO2 and MIL-53(Fe) in the composites, Fe3+ ions can be greatly stabilized in MIL-53(Fe) during the eNRR process, which greatly hinders the catalyst deactivation caused by the electrochemical reduction of Fe3+ ions. Further, the charge transfer ability in the interface of composites can be improved, and thus, the eNRR activity is significantly boosted. These findings provide a promising insight into the preparation of efficient composite electrocatalysts.

Designed Synthesis of Fe/Zr Bimetallic Organic Framework to Enhance the Selective Conversion of H2S to Sulfur.

The development of stable and effective catalysts to convert toxic H2S into high value-added sulfur is essential for production safety and environmental protection. However, the inherent defects of traditional iron- and zirconium-based catalysts, such as poor activity, high oxygen consumption, and low sulfur selectivity, limit their further developments and applications. Herein, the Fe-Zr bimetallic organic framework FeUIO-66(x) with different cubic morphologies was synthesized via a facile solvothermal method. The results indicate that the introduction of Fe not only increases the specific surface area and weak L-sites of the catalyst without changing its crystal structure, which provides enough reaction space and more active sites for the adsorption and activation of H2S, but also reduces the activation energy of the reaction, significantly promoting the selective oxidation of H2S. As a result, the as-obtained FeUIO-66(1) catalyst exhibits the highest desulfurization activity and superior durability and water resistance stability, and its H2S conversion and sulfur selectivity within 50 h are 100 and 88%, respectively. More importantly, the structure of the catalyst after the desulfurization reaction is consistent with that of the fresh counterpart. The study offers new insights into the development of effective and stable bimetallic catalysts to eliminate H2S and recycle sulfur.

Counting d-Orbital Vacancies of Transition-Metal Catalysts for the Sulfur Reduction Reaction.

The electrocatalytic sulfur reduction reaction (SRR) would allow the production of renewable high-capacity rechargeable lithium-sulfur (Li-S) batteries using sustainable and nontoxic elemental sulfur as a cathode material, but its slow reaction rate causes a serious shuttle effect and dramatically reduces the capacity. We found that a catalyst composed of Pd nanoparticles supported by ordered mesoporous carbon (Pd/OMC) had a high reaction rate in the SRR, and a Li-S battery assembled with this catalyst had a low shuttle constant of 0.031 h-1 and a high-rate performance with a specific capacity of 1527 mAh g-1 at 0.1 C which is close to the theoretical value. The high activity of Pd/OMC with a d-orbital vacancy of 0.87 e was predicted from a volcano relationship between the d charge for the metal and the adsorption activation entropy and reaction rate for the SRR by examining Pd, Au, Pt, Rh, and Ru transition-metal nanocatalysts. The strategy of using a single electronic structure descriptor to design high-efficiency SRR catalysts has suggested a way to produce practical Li-S batteries.

Bimetallic Metal-Organic Frameworks MIL-53(xAl-yFe) as Efficient Catalysts for H2S Selective Oxidation.

Catalytic oxidation of H2S is a crucial green pathway that can fully convert H2S into value-added elemental S for commercial use. However, achieving high catalytic stability and S selectivity by traditional-metal-based catalysts still remain a major challenge. Herein, a facile one-step solvothermal strategy is designed for the fabrication of bimetallic MIL-53(xAl-yFe) catalysts. The as-synthesized MIL-53(1Al-5Fe) possesses ample coordinatively unsaturated metal sites, which served as efficient catalytic sites for the selective oxidation of H2S. As a result, the representative MIL-53(1Al-5Fe) achieves a S yield of nearly 100% at 100-160 °C with almost no obvious decrease of catalytic stability in the run of 30 h. Under the defined reaction conditions, the bimetallic metal-organic frameworks are obviously superior to MIL-53(Al) (49.3%) and MIL-53(Fe) (70.5%) in S yield. This study suggests that the introduction of elemental Al into MIL-53(xAl-yFe) could effectively modulate the electronic properties and spatial configuration of the catalysts, further conducing the adsorption and activation of H2S and thus accelerating the dissociation of H2S into a key intermediate S* and improving their catalytic performance.

Efficiently Integrated Desulfurization from Natural Gas over Zn-ZIF-Derived Hierarchical Lamellar Carbon Frameworks.

Selective removal of carbonyl sulfide (COS) and hydrogen sulfide (H2S) is the key step for natural gas desulfurization due to the highly toxic and corrosive features of these gaseous sulfides, and efficient and stable desulfurizers are urgently needed in the industry. Herein, we report a class of nitrogen-functionalized, hierarchically lamellar carbon frameworks (N-HLCF-xs), which are obtained from the structural transformation of Zn zeolitic imidazolate frameworks via controllable carbonization. The N-HLCF-xs possess the desirable characteristics of large Brunauer-Emmett-Teller surface areas (645-923 m2/g), combined primary three-dimensional microporosity and secondary two-dimensional lamellar microstructure, and high density of nitrogen base sites with enhanced pyridine ratio (17.52 wt %, 59.91%). The anchored nitrogen base sites in N-HLCF-xs show improved accessibility, which boosts their interaction with acidic COS and H2S. As expected, N-HLCF-xs can be employed as multifunctional and efficient desulfurizers for selective removal of COS and H2S from natural gas. COS was first transformed into H2S via catalytic hydrolysis, and the produced H2S was then captured and separated and catalyzed oxidation into elemental sulfur. The above continuous processes can be achieved with solo N-HLCF-xs, giving extremely high efficiencies and reusability. Their integrated desulfurization performance was better than many desulfurizers used in the area, such as activated carbon, ß zeolite, MIL-101(Fe), K2CO3/γ-Al2O3, and FeOx/TiO2.

Highly Poison-Resistant Single-Atom Co-N4 Active Sites with Superior Operational Stability over 460 h for H2 S Catalytic Oxidation.

Efficient catalytic elimination of hydrogen sulfide (H2 S) with high activity and durability in nature gas and blast-furnace gas is very critical for both fundamental catalytic research and applied environmental chemistry. Herein, atomically dispersed Co atom catalysts with Co-N4 sites that can transform H2 S into S with conversion rate of ≈100% are designed and prepared. The representative 4Co-N/NC achieves a sulfur yield of nearly 100% and TOF(Co) of 869 h-1 at 180 °C. Importantly, remarkable long-term durability is achieved as well, with no obvious loss of catalytic activity in the run of 460 h, outperforming most of the reported catalysts. The short bond length and strong cooperation of Co-N are beneficial to improve the structural stability of the Co-N4 centers, and significantly enhanced resistance of water and sulfation over single-atom Co-catalyst. The present mechanism involves the stepwise hydrogen transfer process via the adsorbed *HOO and *HS intermediates.

Structural analysis of glycosaminoglycans from Oviductus ranae.

Oviductus ranae (O.ran.) has been widely used as a tonic and a traditional animal-based Chinese medicine. O.ran. extracts have been reported to have numerous biological activities, including activities that are often associated with mammalian glycosaminoglycans such as anti-inflammatory, antiosteoperotic, and anti-asthmatic. Glycosaminoglycans are complex linear polysaccharides ubiquitous in mammals that possess a wide range of biological activities. However, their presence and possible structural characteristics within O.ran. were previously unknown. In this study, glycosaminoglycans were isolated from O.ran. and their disaccharide compositions were analyzed by liquid chromatography-ion trap/time-of-flight mass spectrometry (LC-MS-ITTOF). Heparan sulfate (HS)/heparin (HP), chondroitin sulfate (CS)/dermatan sulfate (DS) and hyaluronic acid (HA) were detected in O.ran. with varied disaccharide compositions. HS species contain highly acetylated disaccharides, and have various structures in their constituent chains. CS/DS chains also possess a heterogeneous structure with different sulfation patterns and densities. This novel structural information could help clarify the possible involvement of these polysaccharides in the biological activities of O.ran..

Activity and Stability Boosting of an Oxygen-Vacancy-Rich BiVO4 Photoanode by NiFe-MOFs Thin Layer for Water Oxidation.

The introduction of oxygen vacancies (Ov) has been regarded as an effective method to enhance the catalytic performance of photoanodes in oxygen evolution reaction (OER). However, their stability under highly oxidizing environment is questionable but was rarely studied. Herein, NiFe-metal-organic framework (NiFe-MOFs) was conformally coated on oxygen-vacancy-rich BiVO4 (Ov-BiVO4 ) as the protective layer and cocatalyst, forming a core-shell structure with caffeic acid as bridging agent. The as-synthesized Ov-BiVO4 @NiFe-MOFs exhibits enhanced stability and a remarkable photocurrent density of 5.3±0.15 mA cm-2 at 1.23 V (vs. RHE). The reduced coordination number of Ni(Fe)-O and elevated valence state of Ni(Fe) in NiFe-MOFs layer greatly bolster OER, and the shifting of oxygen evolution sites from Ov-BiVO4 to NiFe-MOFs promotes Ov stabilization. Ovs can be effectively preserved by the coating of a thin NiFe-MOFs layer, leading to a photoanode of enhanced photocurrent and stability.

Global Metabolomic and Lipidomic Analysis Reveal the Synergistic Effect of Bufalin in Combination with Cinobufagin against HepG2 Cells.

Chansu, which is prepared from the skin secretions of toad (Bufo bufo gargarizans Cantor), is widely used in traditional Chinese medicine (TCM). Being the principal bioactive constituents of Chansu, bufalin (BFL) and cinobufagin (CBF) have been shown to possess anticancer properties. TCM confers bioactivities through the synergistic effect between potential active ingredients, so as to interfere with the development of the disease, and ultimately achieve the therapeutic effect. We found that the anticancer effect was significantly potentiated by cotreatment with BFL and CBF compared to monotreatment, suggesting their synergistic interaction. To reveal their synergistic mechanisms, metabolomic and lipidomic profiling based on liquid chromatography-mass spectrometry (LC-MS) was utilized to delineate the responses in HepG2 cells after treatment with BFL and CBF individually or in combination. Metabolic pathways, including methionine metabolism, energy metabolism, lipid metabolism, and amino acid metabolism, were modulated and subsequently led to apoptosis and cell cycle arrest of HepG2 cells. In particular, the discrepant regulation of methionine metabolism between the monotreatment and cotreatment with BFL and CBF may account for their synergistic effect. Our study provided novel insights into the mechanistic links between cellular metabolism and the synergistic effect, which may ultimately lead to better treatments for hepatoma.

Highly Active and Sulfur-Resistant Fe-N4 Sites in Porous Carbon Nitride for the Oxidation of H2 S into Elemental Sulfur.

Iron-based catalysts have been widely studied for the oxidation of H2 S into elemental S. However, the prevention of iron sites from deactivation remains a big challenge. Herein, a facile copolymerization strategy is proposed for the construction of isolated Fe sites confined in polymeric carbon nitride (CN) (Fe-CNNχ). The as-prepared Fe-CNNχ catalysts possess unique 2D structure as well as electronic property, resulting in enlarged exposure of active sites and enhancement of redox performance. Combining systematic characterizations with density functional theory calculation, it is disclosed that the isolated Fe atoms prefer to occupy four-coordinate doping configurations (Fe-N4 ). Such Fe-N4 centers favor the adsorption and activation of O2 and H2 S. As a consequence, Fe-CNNχ exhibit excellent catalytic activity for the catalytic oxidation of H2 S to S. More importantly, the Fe-CNNχ catalysts are resistant to water and sulfur poisoning, exhibiting outstanding catalytic stability (over 270 h of continuous operation), better than most of the reported catalysts.

Iron-Based Metal-Organic Frameworks as Platform for H2S Selective Conversion: Structure-Dependent Desulfurization Activity.

Three classical Fe-MOFs, viz., MIL-100(Fe), MIL-101(Fe), and MIL-53(Fe), were synthesized to serve as platforms for the investigation of structure-activity relationship and catalytic mechanism in the selective conversion of H2S to sulfur. The physicochemical properties of the Fe-MOFs were characterized by various techniques. It was disclosed that the desulfurization performances of Fe-MOFs with well-defined microstructures are obviously different. Among these, MIL-100(Fe) exhibits the highest catalytic performance (ca. 100% H2S conversion and 100% S selectivity at 100-180 °C) that is superior to that of commercial Fe2O3. Furthermore, the results of systematic characterization and DFT calculation reveal that the difference in catalytic performance is mainly because of discrepancy in the amount of Lewis acid sites. A plausible catalytic mechanism has been proposed for H2S selective conversion over Fe-MOFs. This work provides critical insights that are helpful for rational design of desulfurization catalysts.

In Situ Detection and Imaging of PFOS in Mouse Kidney by Matrix-Assisted Laser Desorption/Ionization Imaging Mass Spectrometry.

Perfluorooctanesulfonic acid (PFOS) is an emerging environmental organic pollutant that has been widely used in daily life products in the last century. Numerous studies showed that the accumulation of PFOS in human through food chain would lead to various disease. However, there is currently no report about its in situ localization in the tissue. In present study, we aimed to develop a reproductive and less-cost method to quantitatively detect and determine the spatial distribution of PFOS in mouse kidney by matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) with a commercially available matrix. α-Cyano-4-hydroxycinnamic acid (CHCA) matrix was optimized for PFOS detection in MALDI-IMS analysis. Compared to other organic matrices, CHCA used in negative ion mode showed less background interference and enhanced MS signal intensity and high spatial resolution (80 µm) for PFOS analysis. The use of a CHCA matrix with an autospray system led to successful identification of the PFOS ion signals on the perfusion kidney tissue. The detection limit was at the µg/mL level, with direct visualization from a MS image. The developed method with the optimized parameters was successfully employed to obtain the PFOS spatial distribution in the kidney collected from mice after the PFOS exposure for 14 days. PFOS was mainly distributed in the kidney cortex region, which was consistent with the histological analysis results. Taken together, a rapid, economic, and efficient method was developed for PFOS detection by MALDI-IMS using a CHCA matrix. Mapping the distribution of PFOS by MALDI-IMS with a CHCA matrix provides an innovative approach for the analysis of environmental pollutants in animal or human tissues.

Analysis of Heparan sulfate/heparin from Colla corii asini by liquid chromatography-electrospray ion trap mass spectrometry.

Colla corii asini (CCA) made from donkey-hide has been widely used as a health-care food and an ingredient of traditional Chinese medicine. Heparan sulfate (HS)/heparin is a structurally complex class of glycosaminoglycans (GAGs) that have been implicated in a wide range of biological activities. However, their presence within CCA, and their possible structural characteristics, were previously unknown. In this study, GAG fractions containing HS/heparin were isolated from CCA and their disaccharide compositions were analyzed by high sensitivity liquid chromatography-ion trap/time-of-flight mass spectrometry (LC-MS-ITTOF). This revealed that, in addition to the eight commonly seen HS disaccharides, the four rare N-unsubstituted disaccharides were also detected in significant quantities. The disaccharide compositions varied significantly between HS/heparin fractions indicating chains with differing domain structures. This novel structural information may lead to a better understanding of the biological activities (i.e. anticoagulation and antitumor action) of CCA.

CYP3A Activation and Glutathione Depletion Aggravate Emodin-Induced Liver Injury.

1,3,8-Trihydroxy-6-methylanthraquinone (emodin), a widely existing natural product in herbal medicines, has been reported to be hepatotoxic, but the exact underlying mechanism is still not fully understood. The objective of the present study was to evaluate the role of CYP3A and glutathione (GSH) in emodin-induced liver injury. Primary human hepatocytes were exposed to emodin with and without addition of CYP3A inducer/inhibitor and GSH synthesis inhibitor. It was found that emodin-mediated cytotoxicity increased when CYP3A was activated and GSH was depleted. Hepatotoxicity induced by emodin in rats by activation/inhibition of CYP3A and depletion of GSH was further investigated. Administration of emodin in combination with l-buthionine sulfoximine (BSO) or dexamethasone (DEX) resulted in aggravated liver injury, whereas pretreatment with ketoconazole (KTZ) suppressed the side effects caused by emodin. In addition, plasma exposure of emodin and its glucuronide metabolite were measured by ultraperformance liquid chromatography triple quadrupole mass spectrometry. Emodin and its glucuronide were lower in BSO-, DEX-, and KTZ- co-treated rats compared with those administered with emodin alone. In conclusion, these mentioned results suggested that CYP3A induction and GSH depletion might be involved in hepatotoxicity induced by emodin. This study may help to understand the risk factors and the mechanism of hepatotoxicity of emodin in humans.

Integrated Metabolomics and Proteomics Approach To Identify Metabolic Abnormalities in Rats with Dioscorea bulbifera Rhizome-Induced Hepatotoxicity.

Previous studies have shown that Dioscorea bulbifera rhizome (DBR) can induce hepatotoxicity in clinical practice. However, its underlying mechanisms remain largely unexplored. In the present study, we investigated the global effect of DBR exposure on the proteomic and metabolomic profiles in rats over a 12-week administration using an integrated proteomics and metabolomics approach. The abundance of 1366 proteins and 58 metabolites in the liver of rats after subchronic exposure to DBR was dose-dependently altered. The results indicated that DBR mainly damaged hepatic cells through the aberrant regulation of multiple systems mainly including purine metabolism, pyrimidine metabolism, taurine and hypotaurine metabolism, and bile acid metabolism. Notably, the deregulated proteins including Pnp, Dpyd, Upp1, and Tymp and the differential metabolites including uridine, uracil, cytidine, thymine, adenine, adenosine, adenosine 3'-monophosphate, and deoxycytidine were well correlated to purine and pyrimidine metabolism, which might be novel pathways involved in metabolic abnormalities in rats with DBR-induced liver damage. Collectively, these findings not only contributed to understanding the mechanisms underlying the hepatotoxicity of DBR, but also illustrated the power of integrated proteomics and metabolomics approaches to improve the identification of metabolic pathways and biomarkers indicative of herb-induced liver injury.

Cu/CeO2 Catalyst for Water-Gas Shift Reaction: Effect of CeO2 Pretreatment.

CuO/CeO2 is a kind of promising catalysts for the water-gas shift (WGS) reaction. Efforts were put in to improve its performance through modification of CeO2 support. In this study, portions of CeO2 prepared by a co-precipitation method were separately annealed at 300 °C in air, under vacuum and with H2 , and were used as supports for the fabrication of CuO/CeO2 catalysts. The physicochemical properties of the catalysts were characterized by X-ray diffraction, N2 -physisorption, inductively coupled plasma, Raman spectroscopy, CO2 temperature-programmed desorption, and H2 temperature-programmed reduction techniques. The relation between catalytic performances and physicochemical properties of the CuO/CeO2 catalysts were discussed. Among the three catalysts, the one with CuO supported on H2 -reduced CeO2 shows the highest catalytic activity, mainly due to strong CuO-CeO2 synergetic interaction and high concentration of Frenkel-type oxygen vacancies. The superior catalytic activities can also be attributed to the Cu0 crystals of small size and the oxygen vacancies in non-stoichiometric CeO2-x .

Amino-Modified Fe-Terephthalate Metal-Organic Framework as an Efficient Catalyst for the Selective Oxidation of H2S.

Classical amino-functionalized Fe-terephthalate metal-organic framework NH2-MIL-53(Fe) and its parent framework MIL-53(Fe) were prepared via simple hydrothermal methods. The catalytic performaces of these two Fe-MOFs were explored for the selective oxidation of H2S. The physicochemical properties of the fresh and used Fe-MOFs catalysts were investigated by XRD, BET, SEM, FT-IR, CO2-TPD, and XPS techniques. It was found that the introduction of amino groups reduces the activation energies for H2S oxidation and endows this catalyst surface with moderate basic sites. As a result, the NH2-MIL-53(Fe) catalyst displays high H2S conversion and near 100% S selectivity in the temperature range of 130-160 °C, outperforming commercial Fe2O3 and activated carbon. Moreover, a plausible reaction route for H2S selective oxidation over NH2-MIL-53(Fe) is proposed. This work opens up the possibility of utilizing MOFs as efficient catalyst for desulfuration reactions.

Efficient low-temperature soot combustion by bimetallic Ag-Cu/SBA-15 catalysts.

In this study, the effects of copper (Cu) additive on the catalytic performance of Ag/SBA-15 in complete soot combustion were investigated. The soot combustion performance of bimetallic Ag-Cu/SBA-15 catalysts was higher than that of monometallic Ag and Cu catalysts. The optimum catalytic performance was acquired with the 5Ag1-Cu0.1/SBA-15 catalyst, on which the soot combustion starts at Tig=225°C with a T50=285°C. The temperature for 50% of soot combustion was lower than that of conventional Ag-based catalysts to more than 50°C (Aneggi et al., 2009). Physicochemical characterizations of the catalysts indicated that addition of Cu into Ag could form smaller bimetallic Ag-Cu nanolloy particles, downsizing the mean particle size from 3.7nm in monometallic catalyst to 2.6nm in bimetallic Ag-Cu catalyst. Further experiments revealed that Ag and Cu species elicited synergistic effects, subsequently increasing the content of surface active oxygen species. As a result, the structure modifications of Ag by the addition of Cu strongly intensified the catalytic performance.

Investigation of Dioscorea bulbifera Rhizome-Induced Hepatotoxicity in Rats by a Multisample Integrated Metabolomics Approach.

The use of herbal medicines continues to expand globally, meanwhile, herb-associated hepatotoxicity is becoming a safety issue. As a conventional Chinese medicinal herb, Dioscorea bulbifera rhizome (DBR) has been documented to cause hepatic toxicity. However, the exact underlying mechanism remains largely unexplored. In the present study, we aimed to profile entire endogenous metabolites in a biological system using a multisample integrated metabolomics strategy. Our findings offered additional insights into the molecular mechanism of the DBR-induced hepatotoxicity. We identified different metabolites from rat plasma, urine, and feces by employing gas chromatography-mass spectrometry in combination with multivariate analysis. In total, 55 metabolites distributed in 33 metabolic pathways were identified as being significantly altered in DBR-treated rats. Correlation network analysis revealed that the hub metabolites of hepatotoxicity were mainly associated with amino acid, bile acid, purine, pyrimidine, lipid, and energy metabolism. As such, DBR affected the physiological and biological functions of liver via the regulation of multiple metabolic pathways to an abnormal state. Notably, our findings also demonstrated that the multisample integrated metabolomics strategy has a great potential to identify more biomarkers and pathways in order to elucidate the mechanistic complexity of toxicity of traditional Chinese medicine.