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1.
Ying Yong Sheng Tai Xue Bao ; 34(8): 2142-2152, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37681378

ABSTRACT

To understand the variations in greenhouse gas fluxes during the process of returning cropland to wetland in the Sanjiang Plain, we selected naturally restored wetlands of 4, 7, 11, 16 and 20 years as research objects to compare with a cultivated site (soybean plantation for 13 years) and an uncultivated marsh dominated by Deyeuxia purpurea and Carex schmidtii. We measured carbon dioxide (CO2) and methane (CH4) fluxes using a static chamber-gas chromatography and explored the main influencing factors. The results showed that there were seasonal variations in growing-season CO2 and CH4 fluxes of the restored wetlands, with the seasonal trends in greenhouse gases becoming gradually similar to that of natural marsh with increasing restoration time. The mean growing-season CO2 fluxes increased during the early stage of restoration, but then decreased during the late stage, which decreased from 893.4 mg·m-2·h-1 to 494.0 mg·m-2·h-1 in the 4-year and 20-year sites, respectively. Mean CH4 fluxes increased with restoration time, ranging from a weak CH4 sink (soybean fields, -0.6 mg·m-2·h-1) to a CH4 source of 87.8 mg·m-2·h-1(20-year restored site). The CH4 fluxes of experimental plots were consistently lower than that of natural marsh (96.4 mg·m-2·h-1). Increases in water level and soil conductivity resulting from restoration were the main driving factors for the decrease in CO2 fluxes. The increases in water level and soil dissolved organic carbon resulting from restoration were the primary drivers for the increase of CH4 fluxes in the restored wetlands. The global warming potentials increased with restoration time, ranging from 27.8 t·CO2-eq·hm-2(soybean fields) to 130.8 t·CO2-eq·hm-2(plot of 20-year restoration), which gradually approached that of natural marsh (156.3 t·CO2-eq·hm-2). The emission of GHGs from restored wetlands in the Sanjiang Plain gradually approached those of natural marsh. Further monitoring is required to identify the maturity of restored wetlands for achieving greenhouse gas emissions equivalent to that of natural marshland.


Subject(s)
Greenhouse Gases , Wetlands , Carbon Dioxide , China , Soil , Glycine max , Water
2.
J Asian Nat Prod Res ; 17(4): 329-32, 2015.
Article in English | MEDLINE | ID: mdl-25295637

ABSTRACT

Two pairs of new enantiomers, lucidulactones A and B (1 and 2), and two known compounds were isolated from Ganoderma lucidum. Their structures were determined by means of spectroscopic methods. The chiral HPLC was used to separate the ( - )- and (+)-antipodes of the new compounds.


Subject(s)
Ganoderma/chemistry , Lactones/isolation & purification , China , Chromatography, High Pressure Liquid , Lactones/chemistry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Reishi/chemistry , Stereoisomerism , Triterpenes/chemistry
3.
J Asian Nat Prod Res ; 17(1): 20-6, 2015.
Article in English | MEDLINE | ID: mdl-25359634

ABSTRACT

Two new dopamine derivatives divesamides A (1) and B (2), along with six known N-containing compounds were isolated from the Chinese black ant (Polyrhachis dives). Their structures were determined on the basis of spectroscopic methods. Compound 1 is a racemate, and chiral HPLC separation yielded a pair of antipodes. The absolute configuration of (+)-1 was assigned by a computational method. The double signals in the (1)H and (13)C NMR spectra of 2 that resulted from the presence of a formamide group were discussed. The T- and B-lymphocytes proliferation assay showed that 2 has moderate immunosuppressive activity toward T- and B-lymphocytes proliferation at a concentration of 20 µM.


Subject(s)
Ants/chemistry , Dopamine/analogs & derivatives , Dopamine/isolation & purification , Immunosuppressive Agents/isolation & purification , Immunosuppressive Agents/pharmacology , Animals , B-Lymphocytes/drug effects , China , Chromatography, High Pressure Liquid , Dopamine/chemistry , Dopamine/pharmacology , Formamides/chemistry , Formamides/pharmacology , Immunosuppressive Agents/chemistry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Stereoisomerism , Structure-Activity Relationship , T-Lymphocytes/drug effects
4.
Zhongguo Zhong Yao Za Zhi ; 39(17): 3395-8, 2014 Sep.
Article in Chinese | MEDLINE | ID: mdl-25522637

ABSTRACT

According to the existing Provisions for Drug Registration (SFDA Order No. 28), applications for new drugs of traditional Chinese medicine are divided into two parts: the applications for drug clinical trial and for drug production (including new drug certificate). It will last for about 10 years from the application for drug clinical trial to get approving, and it also remains many problems and the low probability to succeed. From the sight of pharmaceutical review, there are mainly two aspects of regulatory compliance and technical issues, mainly for changes without approval of the competent authorities of the country. For example, sample preparation and approval of clinical trial process are significant changes. Technical problems are reporting incomplete data or information submitted does not comply with the technical requirements for review, such as: production process validation does not provide information, the preparation of samples for clinical trials and field inspection, production information, or the information provided does not meet the technical requirements. This paper summarizes the frequently asked questions and to make recommendations to advise applicants concerned, timely detection of problems, avoid risk, improving the quality and efficiency of the application for registration.


Subject(s)
Drug Approval/legislation & jurisprudence , Drug Evaluation/legislation & jurisprudence , Legislation, Drug , Medicine, Chinese Traditional , China , Humans
5.
Chem Biodivers ; 8(12): 2270-6, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22162164

ABSTRACT

Two coriamyrtin-type sesquiterpenes, fengfangin A (1) and tutin (2), and six diarylheptanoids, namely alnusone (3), centrolobol (4), muricarpone B (5), 1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)heptan-3-one (6), (3S)-1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)heptan-3-ol (7), and (3S)-1-(4-hydroxyphenyl)-7-(3,4-dihydroxyphenyl)heptan-3-ol (8), were isolated from the 95% EtOH extract of nidus vespae, the nest of Polistes species. Their structures were identified by spectroscopic methods. Compounds 1 and 8 are new products. The absolute configuration of 1 was determined by single-crystal X-ray diffraction analysis using Flack parameter. The biological tests showed that compounds 5, 6, and 8 could inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells with IC(50) values in the range of 13-17 µM, whereas the sesquiterpenes were inactive in this assay (>25 µM). In addition, the ecological significance of the presence of neurotoxic sesquiterpene lactones in nidus vespae is briefly discussed.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/isolation & purification , Diarylheptanoids/isolation & purification , Nitric Oxide/adverse effects , Sesquiterpenes/isolation & purification , Wasps/chemistry , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cell Line , Diarylheptanoids/chemistry , Diarylheptanoids/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Medicine, Chinese Traditional , Mice , Models, Molecular , Molecular Structure , Sesquiterpenes/chemistry , Sesquiterpenes/pharmacology , Wasps/growth & development
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