Main components from cultivated and wild Nardostachyos Radix et Rhizoma by LC-MS and GC-MS / 中国中药杂志

In this study, ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and gas chromatography-mass spectrometry(GC-MS) were combined with non-targeted metabonomic analysis based on multivariate statistics analysis, and the content of five indicative components in nardosinone was determined and compared by UPLC. The main chemical components of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma were comprehensively analyzed. The results of multivariate statistical analysis based on liquid chromatography-mass spectrometry(LC-MS) and GC-MS were consistent. G1 and G2 of the imitative wild cultivation group and G8-G19 of the wild group were clustered into category 1, while G7 of the wild group and G3-G6 of the imitative wild cultivation group were clustered into category 2. After removing the outlier data of G1, G2, and G7, G3-G6 of the imitative wild cultivation group were clustered into one category, and G8-G19 of the wild group were clustered into the other category. Twenty-six chemical components were identified according to the positive and negative ion modes detected by LC-MS. The content of five indicative components(VIP>1.5) was determined using UPLC, revealing that chlorogenic acid, isochlorogenic acid A, isochlorogenic acid C, linarin, nardosinone, and total content in the imitative wild cultivation group were 1.85, 1.52, 1.26, 0.90, 2.93, and 2.56 times those in the wild group, respectively. OPLS-DA based on GC-MS obtained 10 diffe-rential peaks. Among them, the relative content of α-humulene and aristolene in the imitative wild cultivation group were extremely significantly(P<0.01) and significantly(P<0.05) higher than that in the wild group, while the relative content of 7 components such as 5,6-epoxy-3-hydroxy-7-megastigmen-9-one, γ-eudesmol, and juniper camphor and 12-isopropyl-1,5,9-trimethyl-4,8,13-cyclotetrade-catriene-1,3-diol was extremely significantly(P<0.01) and significantly(P<0.05) lower than that in the wild group, respectively. Therefore, the main chemical components of the imitative wild cultivation group and wild group were basically the same. However, the content of non-volatile components in the imitative wild cultivation group was higher than that in the wild group, and the content of some volatile components was opposite. This study provides scientific data for the comprehensive evaluation of the quality of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma.

Establishment and Application of Identification Method for Fishy Odor of Cordyceps Based on HS-SPME/GC-QQQ-MS/MS / 中国实验方剂学杂志

Objective:To establish and apply a new practical analytical method for identifying the fishy odor of Cordyceps based on headspace-solid phase microextraction-gas chromatography-triple quadrupole mass spectrometry （HS-SPME/GC-QQQ-MS/MS） technique. Method:The InertCap Pure-WAX capillary column （0.25 mm×30 m， 0.25 μm） was used for chromatographic separation. The injection port temperature was set at 250 ℃. The injection mode was split injection with a ratio of 5∶1. High purity helium was used as the carrier gas and control mode was set to constant pressure. The column flow rate was 1.43 mL∙min^-1， the linear velocity was 43.3 cm∙s^-1， and the purge flow rate was 3.0 mL∙min^-1. The chromatographic column temperature program as follows：maintained the initial temperature at 50 ℃ for 5 min， and increased the temperature at a rate of 10 ℃∙min^-1 to 250 ℃， held for 10 min. The column equilibrium time was 2.0 min. The ion source of mass spectrographic analysis was electron ionization with ion source temperature of 200 ℃， and the monitoring mode was set to multiple reaction monitoring. Result:Seven batches of Cordyceps samples were collected， including 3 batches from Sichuan， 3 batches from Qinghai and 1 batch from Tibet. There were six batches of counterfeits， including 3 batches from Sichuan， 2 batches from Guizhou and 1 batch in Xinjiang. A total of 81 volatile compounds were screened out in Cordyceps， which could be divided into 13 types （esters， ketones， aldehydes and others） according to the compound structure， indicating that the fishy odor of Cordyceps was a complex odor. There was no significant difference in the types of volatile compounds of Cordyceps from different regions， which suggested that these volatile compounds in Cordyceps produced in Tibet （Naqu）， Qinghai （Yushu and Guoluo） and Sichuan （Litang， Rangtang and Seda） were relatively consistent. However， the contents of some volatile compounds in Cordyceps produced in different regions were quite different， and 16 volatile compounds with significant difference were screened out， including 1-methoxy-2-propyl acetate， <italic>γ</italic>-octalactone， hexyl acetate and others， those compounds maybe could been used as the quality markers for identification of regions of Cordyceps. There was a large difference in volatile compounds between Cordyceps and its counterfeits， and 34 volatile compounds were screened out， including ethyl acetate， acetophenone， 2-ethyl-1-hexanol and others， those compounds maybe could been used as the quality markers for authenticity identification of Cordyceps. Conclusion:In summary， the established method for identifying the fishy odor of Cordyceps in this paper has the characteristics of high sensitivity， accuracy and simplicity， which can provide reference for the analysis of volatile compounds in other Chinese herbal medicines.

Study on RhBMP-2 induced osteoporosis rat BMSCs in vitro osteogenesis and VEGF expression / 中国骨伤

<p><b>OBJECTIVE</b>To observe the impact of bone morphogenetic protein-2 (rhBMP-2) on bone marrow stromal cells (BMSCs) osteogenesis in vitro and vascular endothelial growth factors (VEGF) expression in bone osteoporotic to prevent and treat the osteoporosis.</p><p><b>METHODS</b>Twenty 6-month-old female SD rats weighted (300±20) g underwent bilateral ovariectomized. At 3 months after operation, dual-energy X-ray absorptiometry was used to measure bone mineral density of rats,the values were compared with preoperative to ensure the model successfully, and the osteoporosis rats' BMSCs were cultured by bone marrow adherent cultured and the BMSCs morphology was observed under a phase contrast microscope upside down. The osteoporosis rats' BMSCs at the 2nd generation (p2) were randomly divided into experimental and control groups and were added complete medium (containing rhBMP-2) and osteogenic induced liquid, respectively. Two weeks later, the formation of cell calcium nodules were detected by Alizarin red staining method,alkaline phosphatase activity was measured by enzyme standard instrument and the expression of VEGF was detected by RT-PCT method.</p><p><b>RESULTS</b>(1)Whole body bone mineral density of rats before and after operation were (0.179±0.007), (0.158±0.006) g/cm2,there was statistically significant (t=4.180,P< 0.05). (2)Alizarin red staining at 2 weeks after osteogenesis induced by BMSCs (P2) in the experimental group had more strong dyeing effect than the control group obviously. (3)Alkaline phosphatase activity at 2 weeks after osteogenesis induced by BMSCs (P2) of the experimental group (15.62±1.27) ug/gprot was significantly higher than that of the control group (8.62±0.93) ug/gprot,there was statistically significant (t=7.709, P<0.01). (4)The expression of VEGF at 2 weeks after osteogenesis induced by BMSCs (P2) of the experimental group 3.723±0.143 was significantly higher than that of the control group 0.950±0.072, there was statistically significant (t=29.462, P<0.01).</p><p><b>CONCLUSION</b>RhBMP-2 can improve the in-vitro osteogenesis ability of ovary osteoporosis rat BMSCs, promote the VEGF expression of osteogenesis factor. Regulating the VEGF expression may be one of the mechanisms of BMP-2 to participate in bone metabolism.</p>

Research Progress in Cofactor Engineering of Xylose Metabolism in Recombinant Saccharomyces cerevisiae / 中国生物工程杂志

Cofactor engineering, a vital part of metabolism engineering, changes the redox cofactor regeneration approach. Its main goal is to rebuild the components of metabolic products. The bioconversion of xylose for the production of ethanol is being studied intensively because ethanol is an alternative energy source and a potential liquid fuel. Saccharomyces cerevisiae has been traditionally used in producing ethanol from fermentable sugars but it cannot utilize xylose, only its isomer xylulose. Introduction of the xylose fermentation pathway from Pichia stipitis into S. cerevisiae enables xylose utilization in recombinant S. cerevisiae, but the ethanol yields of xylose fermentation with recombinant S. cerevisiae has been low and large amounts of the byproduct xylitol are produced. The major reason is that the catabolism of xylose with the fungal pathway leads an imbalance of redox cofactor. The process of the catabolism of xylose requires NADPH and NAD~+, both of which have to be regenerated in separated processes. More and more attention has therefore focused on the redox cofactor balance in S. cerevisia. The research progress of cofactor engineering to solve the imbalance of redox cofactor in xylose metabolism recombinant S. cerevisiae was introduced. This included expression of transhydrogenase, increasing the utilization of NADPH, and achieving the anaerobic reoxidation of NADH. Reversing the cofactor specificity of enzymes is another effective way.

Progress in the pathway engineering of ethanol fermentation from xylose utilising recombinant Saccharomyces cerevisiae / 生物工程学报

Pathway engineering was the third generation of gene engineering. Its main goals were to change metabolic flux and open a new metabolic pathway in organism. Application of recombinant DNA methods to restructure metabolic networks can improve production of metabolite and protein products by altering pathway distributions and rates. Ethanol is the most advanced liquid fuel because it is environmentally friendly. Enhancing fuel ethanol production will require developing lower-cost feedstock, and only lignocellulosic feedstock is available in sufficient quantities to substitute for corn starch. Xylose is the major pentose found in lignocellulosic materials and after glucose the most abundant sugar available in nature. Recently a lot of attentions have been focused on designing metabolic pathway of Saccharomyces cerevisiae in order to expand the substrate of ethanol fermentation, because it is a traditional ethanol producing strain and has wonderful properties for ethanol industry. However, it can not utilize xylose but convert the isomer, xylulose. Many attempts are based on introducing the genes in the pathway of xylose metabolism. The further research includes overexpressing the key enzyme or decreasing the unimportant flux. The sugars in lignocellulose hydrolyzates, therefore, could be efficiently utilized. Here, we describe the ethanol pathway engineering progress in ethanol fermentation from xylose with recombinant Saccharomyces cerevisiae.