Transcriptomics comparison reveals the diversity of ethylene and methyl-jasmonate in roles of TIA metabolism in Catharanthus roseus.

BACKGROUND: The medicinal plant, Catharanthus roseus (C. roseus), accumulates a wide range of terpenoid indole alkaloids (TIAs). Ethylene (ET) and methyl-jasmonate (MeJA) were previously reported as effective elicitors for the production of various valuable secondary metabolites of C. roseus, while a few ET or MeJA induced transcriptomic research is yet reported on this species. In this study, the de-novo transcriptome assembly of C. roseus is performed by using the next-generation sequencing technology. RESULTS: The result shows that phenolic biosynthesis genes respond specifically to ET in leaves, monoterpenoid biosynthesis genes respond specifically to MeJA in roots. By screening the database, 23 ATP-binding cassette (ABC) transporter partial sequences are identified in C. roseus. On this basis, more than 80 key genes that encode key enzymes (namely TIA pathway, transcriptional factor (TF) and candidate ABC transporter) of alkaloid synthesis in TIA biosynthetic pathways are chosen to explore the integrative responses to ET and MeJA at the transcriptional level. Our data indicated that TIA accumulation is strictly regulated by the TF ethylene responsive factor (ERF) and bHLH iridoid synthesis 1 (BIS1). The heatmap, combined with principal component analysis (PCA) of C. roseus, shows that ERF co-expression with ABC2 and ABC8 specific expression in roots affect the root-specific accumulation of vinblastine in C. roseus. On the contrast, BIS1 activities follow a similar pattern of ABC3 and CrTPT2 specific expression in leaves, which affects the leaf-specific accumulation of vindoline in C. roseus. CONCLUSIONS: Results presented above illustrate that ethylene has a stronger effect than MeJA on TIA induction at both transcriptional and metabolite level. Furthermore, meta-analysis reveals that ERF and BIS1 form a positive feedback loop connecting two ABC transporters respectively and are actively involved in TIAs responding to ET and MeJA in C. roseus.

Production of Laccase by a New Myrothecium verrucaria MD-R-16 Isolated from Pigeon Pea [Cajanus cajan (L.) Millsp.] and its Application on Dye Decolorization.

The present study was conducted to screen a laccase-producing fungal endophyte, optimize fermentation conditions, and evaluate the decolorization ability of the laccase. A new fungal endophyte capable of laccase-producing was firstly isolated from pigeon pea and identified as Myrothecium verrucaria based on a ITS-rRNA sequences analysis. Meanwhile, various fermentation parameters on the laccase production were optimized via response surface methodology (RSM). The optimal fermentation conditions were a fermentation time of five days, temperature 30 °C and pH 6.22. Laccase activity reached 16.52 ± 0.18 U/mL under the above conditions. Furthermore, the laccase showed effective decolorization capability toward synthetic dyes (Congo red, Methyl orange, Methyl red, and Crystal violet) in the presence of the redox mediator ABTS, with more than 70% of dyes decolorizing after 24 h of incubation. Additionally, the activity of laccase was relatively stable with pH (4.5-6.5) and a temperature range of 35-55 °C. Therefore, the high laccase production of the strain and the new fungal laccase could provide a promising alterative approach for industrial and environmental applications.

GC-MS Metabolomic Analysis to Reveal the Metabolites and Biological Pathways Involved in the Developmental Stages and Tissue Response of Panax ginseng.

Ginsenosides, the major compounds present in ginseng, are known to have numerous physiological and pharmacological effects. The physiological processes, enzymes and genes involved in ginsenoside synthesis in P. ginseng have been well characterized. However, relatively little information is known about the dynamic metabolic changes that occur during ginsenoside accumulation in ginseng. To explore this topic, we isolated metabolites from different tissues at different growth stages, and identified and characterized them by using gas chromatography coupled with mass spectrometry (GC-MS). The results showed that a total of 30, 16, 20, 36 and 31 metabolites were identified and involved in different developmental stages in leaf, stem, petiole, lateral root and main root, respectively. To investigate the contribution of tissue to the biosynthesis of ginsenosides, we examined the metabolic changes of leaf, stem, petiole, lateral root and main root during five development stages: 1-, 2-, 3-, 4- and 5-years. The score plots of partial least squares-discriminate analysis (PLS-DA) showed clear discrimination between growth stages and tissue samples. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis in the same tissue at different growth stages indicated profound biochemical changes in several pathways, including carbohydrate metabolism and pentose phosphate metabolism, in addition, the tissues displayed significant variations in amino acid metabolism, sugar metabolism and energy metabolism. These results should facilitate further dissection of the metabolic flux regulation of ginsenoside accumulation in different developmental stages or different tissues of ginseng.

Geraniin exerts cytoprotective effect against cellular oxidative stress by upregulation of Nrf2-mediated antioxidant enzyme expression via PI3K/AKT and ERK1/2 pathway.

BACKGROUND: Geraniin, an active compound with remarkable antioxidant activity, was isolated from Geranium sibiricum. The present study aimed to investigate whether geraniin has the ability to activate Nrf2, induce antioxidant enzyme expression and protect cells from oxidative damage. METHODS: The cells were pretreated with geraniin for 24h and exposed to hydrogen peroxide (H2O2) for 4h. Intracellular reactive oxygen species (ROS) levels, mitochondrial membrane potential and apoptosis were measured. We also investigated intracellular glutathione (GSH) levels and changes in nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated signaling cascade in cells treated with geraniin. RESULTS: We investigated the protective effects of geraniin against H2O2-induced apoptosis in HepG2 cells. Geraniin significantly reduced H2O2-induced oxidative damage in a dose dependent manner. Further, geraniin induced the expression of heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase-1 (NQO1) and level of glutathione (GSH) in a concentration- and time-dependent manner, and increased Nrf2 nuclear translocation. The Nrf2-related cytoprotective effects of geraniin were PI3K/AKT and extracellular signal-regulated protein kinase1/2 (ERK1/2) pathway-dependent. However, inhibitors of PI3K/AKT and ERK1/2 (LY294002 or U0126) not only suppressed geraniin-induced nuclear translocation of Nrf2 but also abolished the expression of HO-1, NQO1 and GSH. CONCLUSIONS: These results demonstrated that geraniin induced Nrf2-mediated expression of antioxidant enzymes HO-1 and NQO1, presumably via PI3K/AKT and ERK1/2 signaling pathways, thereby protecting cells from H2O2-induced oxidative cell death. GENERAL SIGNIFICANCE: Geraniin, at least in part, offers an antioxidant defense capacity to protect cells from the oxidative stress-related diseases.

Geraniin induces apoptosis of human breast cancer cells MCF-7 via ROS-mediated stimulation of p38 MAPK.

Geraniin, a typical ellagitannin isolated from Phyllanthus urinaria Linn, has been found to possess a range of bioactive properties. In the present study, we found that Geraniin showed potent anti-proliferative effects on human breast cancer MCF-7 cells. The IC50 values were 9.94, 17.98 and 42.32 µM after 72-, 48- and 24-h treatment, respectively. Meanwhile, Geraniin could remarkably disrupt mitochondrial membrane potential and arrest S phase cell cycle. Western-blot analysis showed that Geraniin induced phosphorylation of the anti-apoptotic Bcl-2, and the cleavage of poly (ADP-ribose) polymerase (PARP) and caspase-3 in MCF-7 cells. Moreover, Geraniin treatment activated p38 mitogen-activated protein kinase (p38 MAPK) and the effect was blunted in MCF-7 cells with the treatment of a specific p38 inhibitor SB203580. Geraniin could generate intracellular reactive oxygen species (ROS), activate p38 MAPK then induce the apoptosis in MCF-7 cells, such phenomena was abrogated by pretreatment with N-acetyl-l-cysteine. In general, these results support the conclusion that Geraniin-induced apoptosis is mediated via ROS-mediated stimulation of p38 MAPK signaling.

High-speed homogenization coupled with microwave-assisted extraction followed by liquid chromatography-tandem mass spectrometry for the direct determination of alkaloids and flavonoids in fresh Isatis tinctoria L. hairy root cultures.

A new, simple and efficient analysis method for fresh plant in vitro cultures-namely, high-speed homogenization coupled with microwave-assisted extraction (HSH-MAE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-was developed for simultaneous determination of six alkaloids and eight flavonoids in Isatis tinctoria hairy root cultures (ITHRCs). Compared with traditional methods, the proposed HSH-MAE offers the advantages of easy manipulation, higher efficiency, energy saving, and reduced waste. Cytohistological studies were conducted to clarify the mechanism of HSH-MAE at cellular/tissue levels. Moreover, the established LC-MS/MS method showed excellent linearity, precision, repeatability, and reproducibility. The HSH-MAE-LC-MS/MS method was also successfully applied for screening high-productivity ITHRCs. Overall, this study opened up a new avenue for the direct determination of secondary metabolic profiles from fresh plant in vitro cultures, which is valuable for improving quality control of plant cell/organ cultures and sheds light on the metabolomic analysis of biological samples. Graphical Abstract HSH-MAE-LC-MS/MS opened up a new avenue for the direct determination of alkaloids and flavonoids in fresh Isatis tinctoria hairy root cultures.

Effective bioconversion of sophoricoside to genistein from Fructus sophorae using immobilized Aspergillus niger and Yeast.

In this study, sophoricoside from Fructus sophorae was highly bioconversed to genistein by co-immobilized Aspergillus niger and Yeast. Bioconversion conditions for genistein were optimized with single-factor experiments. The optimal conditions were as follows: microbial concentration 1.5 × 10(7) cells/mL, wet weight of microorganisms beads 10.0 g/g material, pH 5, ratio of liquid to solid 25:1 (mL/g), temperature 32 °C and time 24 h. Under these conditions, a 34.45-fold increase in production of genistein was observed with a bioreactor. Moreover, the antioxidant activities of the extracts from the fermented and untreated F. sophorae were 0.287 ± 0.11, 0.384 ± 0.08 mg/mL (IC50) and 1.84 ± 0.13, 1.28 ± 0.25 mmol Fe(II)/g, according to the DPPH test and FRAP assay, respectively. The results indicated that the method described in the current work were valuable procedure for the production of genistein, which is of most importance for industrial scale applications as well as food industry.

[Research progress on plant resources distribution of vitexin and its pharmacological effects].

Vitexin, a naturally occurring flavone glycoside in plants, has many pharmacological effects, which is widely distributed in nature. This paper reviewed the research progress of the distribution of vitexin in the plant resources and its pharmacological effects, and summarized its application prospects, aiming to provide a useful reference for the development of vitexin-enriched plant resources.

An effective negative pressure cavitation-microwave assisted extraction for determination of phenolic compounds in P. calliantha H. Andr.

A novel negative pressure and microwave assisted extraction technique (NMAE) was first proposed and applied for extraction of phenolic compounds from pyrola. [C4MIM]BF4 aqueous solution was selected as extraction solvent. Optimal extraction conditions were microwave power 700 W, negative pressure -0.07 MPa, temperature 40 °C, liquid-solid ratio 20 : 1, ionic liquid (IL) concentration 0.5 M, extraction time 15 min. The predominance of NMAE was investigated by comparing with microwave-assisted extraction (MAE) and negative pressure cavitation extraction (NPCE) using a first-order kinetics equation. The C∞ values of the target compounds by NMAE were from 0.406 to 5.977 mg g⁻¹ higher than these by MAE and NPCE, which indicated that NMAE had higher extraction yields. The K values of NMAE were also the highest; it was testified that the target compounds could be transferred from matrix into solvent much more effectively by NMAE than by MAE and NPCE. In addition, the NMAE method was validated in terms of repeatability and reproducibility, the relative standard deviation for relative recovery was lower than 5.43 and 8.78%, respectively. Therefore, NMAE was a developed extraction technique for analytical sample preparation. The RP-HPLC-UV method was also successfully applied for the quantification of six target compounds in pyrola.

Effect of corilagin on membrane permeability of Escherichia coli, Staphylococcus aureus and Candida albicans.

Corilagin is a member of polyphenolic tannins. Its antimicrobial activity and action mechanism against Escherichia coli, Staphylococcus aureus and Candida albicans were investigated through membrane permeability. Crystal violet staining determination, outer membrane (OM) and inner membrane (IM) permeability, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and atomic force microscopy (AFM) were used as methods for our investigation. The minimum inhibitory concentrations were 62.5, 31.25 and 62.5 µg/mL for E. coli, S. aureus and C. albicans, respectively. Crystal violet results and SDS-PAGE of supernatant proteins showed that corilagin dose-dependently affected membrane permeability of E. coli and C. albicans but not of S. aureus. OM and IM permeability assays revealed comparable results for E. coli. By using AFM, we demonstrated extensive cell surface alterations of corilagin-treated E. coli and C. albicans. SDS-PAGE of precipitated proteins revealed possible targets of corilagin, i.e. Fib, Sae R, Sar S in S. aureus and Tye 7p in C. albicans. In conclusion, corilagin inhibited the growth of E. coli and C. albicans by disrupting their membrane permeability and that of S. aureus by acting on Fib, Sae R and Sar S but not on membrane integrity.

Isolation and characterization of 13 novel polymorphic microsatellite markers for Pinus koraiensis (Pinaceae).

PREMISE OF THE STUDY: Thirteen polymorphic microsatellite markers were developed to investigate the genetic diversity and population structure of Pinus koraiensis. • METHODS AND RESULTS: Using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) method with three specific PCR primers for screening the positive clones, 13 loci were found to be polymorphic in 78 individuals of P. koraiensis. Across all of the P. koraiensis samples, the number of alleles per locus ranged from two to 11. • CONCLUSIONS: These polymorphic markers will be useful for conservation genetics studies of this species and to inform the development of effective P. koraiensis conservation programs.

Ionic liquid-based microwave-assisted extraction for the determination of flavonoid glycosides in pigeon pea leaves by high-performance liquid chromatography-diode array detector with pentafluorophenyl column.

In this study, an ionic liquid-based microwave-assisted extraction (ILMAE) followed by high-performance liquid chromatography-diode array detector with a pentafluorophenyl column for the extraction and quantification of eight flavonoid glycosides in pigeon pea leaves is described. Compared with conventional extraction methods, ILMAE is a more effective and environment friendly method for the extraction of nature compounds from herbal plants. Nine different types of ionic liquids with different cations and anions were investigated. The results suggested that varying the anion and cation had significant effects on the extraction of flavonoid glycosides, and 1.0 M 1-butyl-3-methylimidazolium bromide ([C4MIM]Br) solution was selected as solvent. In addition, the extraction procedures were also optimized using a series of single-factor experiments. The optimum parameters were obtained as follows: extraction temperature 60°C, liquid-solid ratio 20:1 mL/g and extraction time 13 min. Moreover, an HPLC method using pentafluorophenyl column was established and validated. Good linearity was observed with the regression coefficients (r(2)) more than 0.999. The limit of detection (LODs) (S/N = 3) and limit of quantification (LOQs) (S/N = 10) for the components were less than 0.41 and 1.47 µg/mL, respectively. The inter- and intraday precisions that were used to evaluate the reproducibility and relative standard deviation (RSD) values were less than 4.57%. The recoveries were between 97.26 and 102.69%. The method was successfully used for the analysis of samples of pigeon pea leaves. In conclusion, the developed ILMAE-HPLC-diode array detector using pentafluorophenyl column method can be applied for quality control of pigeon pea leaves and related medicinal products.

Application of ionic liquid-based surfactants in the microwave-assisted extraction for the determination of four main phloroglucinols from Dryopteris fragrans.

An ionic liquid-based surfactant combined with microwave-assisted extraction method, followed by RP-HPLC-diode array detection (DAD) with a core shell column, was successfully applied in extracting and quantifying four major phloroglucinols from Dryopteris fragrans. Eight ionic liquids with different cation and anion were investigated, and 1-octyl-3-methylimidazolium bromide presented the best relative extraction efficiency for four phloroglucinols. The optimum conditions of this method were as follows: ionic liquid concentration 0.75 M, liquid/solid ratio 12:1 mL/g, extraction time 7 min, extraction temperature 50°C, and irradiation power 600 W. The quality analytical parameters of the method were obtained based on the linearity, precision, accuracy, detection, and quantification limits. The recoveries were between 96.90 and 103.5% with standard deviations not higher than 4.7%. Compared with ionic liquid-based heat reflux extraction, ultrasonic-assisted extraction, negative-pressure cavitation extraction, and conventional microwave-assisted extraction, the relative extraction efficiencies of the proposed method for four phloroglucinols increased 1.5-40.4%. The method was successfully applied for the quantification of four major phloroglucinols from D. fragrans. All these results suggest that the developed method represents an excellent alternative for the extraction and quantification of phloroglucinols in other plant materials.

Enrichment and purification of deoxyschizandrin and γ-schizandrin from the extract of Schisandra chinensis fruit by macroporous resins.

In present study, the performance and separation characteristics of 21 macroporous resins for the enrichment and purification of deoxyschizandrin and γ-schizandrin, the two major lignans from Schisandra chinensis extracts, were evaluated. According to our results, HPD5000, which adsorbs by the molecular tiers model, was the best macroporous resin, offering higher adsorption and desorption capacities and higher adsorption speed for deoxyschizandrin and γ-schizandrin than other resins. Columns packed with HPD5000 resin were used to perform dynamic adsorption and desorption tests to optimize the technical parameters of the separation process. The results showed that the best adsorption time is 4 h, the rate of adsorption is 0.85 mL/min (4 BV/h) and the rate of desorption is 0.43 mL/min (2 BV/h). After elution with 90% ethanol, the purity of deoxy-schizandrin increased 12.62-fold from 0.37% to 4.67%, the purity of γ-schizandrin increased 15.8-fold from 0.65% to 10.27%, and the recovery rate was more than 80%.

[Determination of six metal elements in animal samples by flame atomic absorption spectrometry with wet digestion].

The contents of 6 metal elements (Ca, Mg, K, Na, Cu and Fe ) were determined in serum, urine, feces and different tissue and organs (heart, kidney, stomach, liver, spleen, intestine and lung) of Wistar rats and mice by flame atomic absorption spectrometry (FAAS) with wet digestion. The samples were digested by the mixture of HNO3 and HClO4 (4 : 1, V/V) at 120 degrees C, the correlation coefficient for the standard curves was 0.999 4-0.999 8, the relative standard deviation (RSD) was from 0.33% to 4.52%, and the recovery for the samples was from 97.7% to 104.2%, meeting the demand of elements content determination in biological samples. The assay method for the determination of the 6 metal elements in animal samples established in this study has the advantages of easy operation, high sensitivity, less sample requiring and accurate results, and the method can be widely used in the determination of various metal elements in biological samples.

Cajanol inhibits the growth of Escherichia coli and Staphylococcus aureus by acting on membrane and DNA damage.

In the present study, the mechanism of antibacterial activity of cajanol extracted from the roots of Cajanus cajan (L.) Millsp. towards Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was investigated. The antibacterial activity of cajanol was evaluated towards six bacterial strains (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Proteus vulgaris, and Pseudomonas aeruginosa) by the broth microdilution method. It showed strong antibacterial activity towards all bacteria tested with minimal inhibition concentration (MIC) values ranging from 98.90 µM to 197.8 µM. Cajanol-induced death rates in the most sensitive strains ( E.COLI, 96.55 % and S. AUREUS, 97.25 %) were analyzed by flow cytometry. Furthermore, the activity of cajanol on the membranes of E. coli and S. aureus was investigated by using lecithin, phosphate groups, and fluorescence microscopy. Cajanol-induced DNA damage was observed by agarose gel electrophoresis. In summary, cajanol inhibited E. coli only by DNA damage, whereas S. aureus was inhibited by affecting both, the lecithin and phosphate groups on the cellular membrane and DNA. The present study shows that cajanol possesses antibacterial activity in vitro towards both gram-negative and gram-positive bacteria and therefore may be a promising candidate as an antibacterial agent for the therapy of microbial infections.

Preparative enrichment and separation of astragalosides from Radix Astragali extracts using macroporous resins.

The enrichment and separation of astragalosides I-IV (AGs I-IV) were studied on eight macroporous resins in the present study. SA-3 resin offered the best adsorption and desorption capacities for AGs I-IV than other resins. The models of adsorption kinetics were investigated in order to elucidate the mechanism of adsorption. The pseudo-second-order model was the better choice than the pseudo-first-order model to describe the adsorption behavior of AGs I-IV onto SA-3 resin. The equilibrium experimental data were well fitted to Langmuir and Freundlich isotherms. SA-3 resin adsorption chromatography tests were carried out to optimize the separation process of AGs I-IV from Radix Astragali extracts. With the optimum parameters for adsorption and desorption, the contents of AGs I-IV were 8.78-, 11.60-, 10.52- and 11.28-fold increased with the recovery yields being 65.88, 90.92, 84.25 and 94.17%, respectively. The preparative enrichment and separation of AGs I-IV from Radix Astragali extracts can be easily and effectively achieved by SA-3 resin adsorption chromatography. The developed methodology can also be referenced for the separation of other active constituents from herbal materials and manufacture of Radix Astragali products.

[A fluorescent-probe detecting CYP2C9 * 3 DNA].

The mismatched CYP2C9 * 3 DNA was detected by a exciplex fluorescent-probe system. The exciplex fluorescent-probe model system comprises of two 12-mer oligonucleotides fluorescent-probes, complementary to neighbouring sites of a 24 (47) -mer DNA target and plasmid target, each equipped with moieties able to form an exciplex on correct, contiguous hybridization. Very similar results were obtained between the 24-mer target and the 47-mer target when WT and MT systems were detected by the exciplex fluorescent-probe. Exciplex bands at 505 nm were found for both 24(47)-mer WT and 24(47)-mer MT-targets at 5 degrees C, but were not distinctive enough to distinguish 24(47)-mer WT-target and 24(47)-mer MT-target. However the experiments were carried out at Tm, the exciplex band disappeared almost completely for 24(47)-mer MT-target system like control system, and there was still a strong exciplex band for the 24(47)-mer WT target system. Exciplex peaks at 505 nm were seen for the WT circular plasmids system, but not for MT circular plasmids. Therefore, mismatches of CYP2C9 * 3 DNA can be effectively detected by this exciplex construct, giving potential for single nucleotide polymorphism detection.

Voltammetric behavior of the MCF-7 cell cytoplasm and the effect of taxol on voltammetric response.

The aims of this study were to find the electroactive species in the human breast cancer (MCF-7) cell cytoplasm causing a voltammetric response of the cells and to establish a simple and rapid measurement method to obtain strong and direct electrochemical responses objectively reflecting the cell viability. Ultrasonication was carried out for the electrochemical detection. The presence of guanine and xanthine in the MCF-7 cell eluent secreted by the living cells and in the MCF-7 cell cytoplasm was verified by HPLC assay with a DAD system and chemometric method. The concentrations of guanine and xanthine in the MCF-7 cell cytoplasm and the voltammetric response of the MCF-7 cell cytoplasm had higher levels than those of intact cell suspensions. Additionally, taxol caused a decrease of the voltammetric response of the cytoplasm and concentrations of xanthine and guanine in the cytoplasm. Therefore, the origin of the voltammetric response of the MCF-7 cytoplasm was driven by the alteration of the levels of xanthine and guanine, which were related to the cell viability. Thus, the voltammetric response of the ultrasonicated MCF-7 cell suspension could be used to monitor the MCF-7 cell growth and to evaluate the effectiveness of antitumor drugs on tumor suppression.

Determination of main taxoids in Taxus species by microwave-assisted extraction combined with LC-MS/MS analysis.

A method based on microwave-assisted extraction (MAE) has been developed for the determination of paclitaxel and five related taxoids, namely 10-deacetylbaccatin III (10-DAB III), cephalomannine, 10-deacetylpaclitaxel (10-DAT), 7-xyl-10- deacetylpaclitaxel (7-xyl-10-DAT), and 7-epi-10-deacetylpaclitaxel (7-epi-10-DAT) in Taxus species in this study. The influential parameters of the MAE procedure were optimized, and the optimal conditions were as follows: extraction solvent 80% ethanol solution, solid/liquid ratio 1:10 (g/mL), temperature 50 degrees C, and three extraction cycles, each cycle 10 min. The method validation for LC-MS/MS analysis was performed. The LOD and LOQ were 3.16-9.20 and 12.20-30.45 ng/mL, respectively. Repeatability and reproducibility for the six taxiods with RSD ranged from 2.78 to 3.85% and from 5.26 to 6.60%. The recoveries of the method for the six taxoids were 92.6-105.6%. The developed MAE-LC-MS/MS method was also successfully applied to determine the contents of six taxoids in different Taxus species.