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Insignin A, A Novel C_21-Steroidal Aglycone from Biondia insignis

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Chinese Chemical Letters 2000年第12期11卷 1065-1068页

作者： Yuan Hu ZHANG Yue Mao SHEN Yuan Ying WEN Ting Yun KUANG Laboratory of phytochemistry and department of plant Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Laboratory of phytochemistry Institute of BotanyChinese Academy of SciencesBeijing 100093

Insignin A, a new C21-steroidal aglycone having the rare 15,16-seco pregnane skeleton was isolated from the acidic hydrolysis part of the 95% EtOH extract of Biondia insignis. It's structure was identified to be 15R,... 详细信息

关键词： Asclepiadaceae Biondia insignis C21-steroidal aglycone insignin A<

Cytotoxic activity and phytochemical analysis of Arum palaestinum Boiss.

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Asian Pacific Journal of Tropical Biomedicine 2015年第11期5卷 944-947页

作者： Mai Mohammed Farid Sameh Reda Hussein Lamiaa Fawzy Ibrahim Mohammed Ali El Desouky Amr Mohammed Elsayed Ahmad Ali El Oqlah Mahmoud Mohammed Saker department of phytochemistry and plant Systematic National Research Center department of Biochemistry Cairo University department of Biological Sciences Yarmouk University department of plant Biotechnology National Research Center

Objective: To evaluate the in vitro cytotoxic activity of the fractionated extract as well as isolated compounds of Arum palaestinum Boiss.(A. palaestinum)(black calla lily), and to identify the volatile components which may be responsible for the potential antitumor ***: A. palaestinum was collected from its natural habitats and subjected to phytochemical analysis for separation of pure compounds. In vitro cytotoxic activity was investigated against four human carcinoma cell lines Hep2, He La, Hep G2 and MCF7 for the fractionated extract and isolated compounds. While, the diethyl ether fraction was subjected to GC–MS analysis as it exhibited the most potent cytotoxic effect to evaluate the active constituents responsible for the cytotoxic ***: Four flavonoid compounds were isolated(luteolin, chrysoeriol, isoorientin,isovitexin) from the diethyl ether and ethyl acetate. The extracts and the pure isolated compounds showed a significant high antiproliferative activity against all investigated cell lines. The GC–MS analysis revealed the separation and identification of 15 compounds representing 95.01% of the extract and belonging to different groups of chemical ***: The present study is considered to be the first report on the cytotoxic activities carried out on different selected fractions and pure compounds of A. palaestinum to provide evidences for its strong antitumor activities. In addition,chrysoeriol and isovitexin compounds were isolated for the first time from the studied taxa.

关键词： Black calla lily Araceae Flavonoids Cytotoxic acti

Temporal and Spatial Requirement of EMF1 Activity for Arabidopsis Vegetative and Reproductive Development

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Molecular plant 2009年第4期2卷 643-653页

作者： Rosario Sanchez Minjung Y. Kim Myriam Calonje Yong-Hwan Moon Z. Renee Sung department of plant and Microbial Biology University of California Berkeley CA 94720 USA Present address: Heidelberg Institute for plant Science Biodiversity and Plant Systematics Heidelberg University 69120 Heidelberg Germany Present address: department of Molecular Biology Pusan National University 30 Jangjeon-dong Geumjeong-gu Busan 609-735 Korea

EMBRYONIC FLOWER （EMF） genes are required to maintain vegetative development via repression of flower homeotic genes in Arabidopsis. Removal of EMF gene function caused plants to flower upon germination, producing abnormal and sterile flowers. The pleiotropic effect of ernfl mutation suggests its requirement for gene programs involved in diverse developmental processes. Transgenic plants harboring EMF1 promoter：：glucuronidase （GUS） reporter gene were generated to investigate the temporal and spatial expression pattern of EMF1. These plants displayed differential GUS activity in vegetative and flower tissues, consistent with the role of EMF1 in regulating multiple gene programs. EMFI：：GUS expression pattern in emf mutants suggests organ-specific auto-regulation. Sense- and antisense （as） EMF1 cDNA were expressed under the control of stage- and tissue-specific promoters in transgenic plants. Characterization of these transgenic plants showed that EMF1 activity is required in meristematic as well as differentiating tissues to rescue emf mutant phenotype. Temporal removal or reduction of EMF1 activity in the embryo or shoot apex of wild-type seedlings was sufficient to cause early flowering and terminal flower formation in adult plants. Such reproductive cell memory is reflected in the flower MADS-box gene activity expressed prior to flowering in these early flowering plants. However, temporal removal of EMF1 activity in flower meristem did not affect flower development. Our results are consistent with EMF1＇s primary role in repressing flowering in order to allow for vegetative growth.

关键词： EMF1 stage-specific promoter early flowering reproductive cell memory vegetative/reproductive development repression of flower MADS-box genes.

Academician Qi-Yi Xing(Chi-Yi Hsing):pioneer organic chemist of synthetic insulin

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Protein & Cell 2022年第9期13卷 627-630页

作者： Ming-Hua Qiu State Key Laboratory of phytochemistry and plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming650201China

Qi-Yi Xing(Chi-Yi Hsing,November 24th,1911–November 4th,2002)(Fig.1)was one of the remarkable scientist and educators in *** was a pioneer for Chinese Organic Chemistry development,an Academician of the Chinese Academy of Sciences,and a professor at the College of Chemistry and Molecular Engineering in Peking *** was one of the leaders of the synthetic crystalline bovine insulin project in China and a person of outstanding talent in the teaching of organic *** the occasion of 110th anniversary of the establishment of the chemistry department at Peking University,it is also Professor Xing’s 110th birthday,and we pay tribute to his lifelong commitment to the development of organic chemistry,especially protein synthesis,and his teaching style.

关键词： Academician teaching pioneer

Determination of delta-9-tetrahydrocannabinol content of cannabis seizures in Egypt

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Asian Pacific Journal of Tropical Medicine 2017年第3期10卷 291-294页

作者： Ahmed M.A.Souleman Alaa El-Din M.Gaafar Omar M.Abdel-Salam Shaimaa A.ElShebiney department of phytochemistry and plant Systematic National Research CentreCairoEgypt department of Photochemistry National Research CentreCairoEgypt department of Toxicology and Narcotics National Research CentreCairoEgypt

Objective:To determine the delta-9-tetrahydrocannabinol(THC)content of cannabis seizures in ***:Unheated and heated extracts of cannabis seizures were prepared from the dried flowering tops and leaves(marijuana)or from the resin(hashish)and subjected to analysis using high performance liquid chromatography(HPLC).Results:The heated resin extract had the peak of THC in a relative ratio of 31.34%,while extracting the resin directly without heating contained only 18.34%of *** the other hand,marijuana showed minimum percentage of THC at 11.188% on heating and 9.55% without ***:These results indicate the high potency of the abused cannabis plant in the illicit Egyptian market.

关键词： Cannabis Hashish Marijuana THC High performance liquid chromatography

Phytochemical investigation, antioxidant and wound healing activities of Citrullus colocynthis (bitter apple)

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Asian Pacific Journal of Tropical Biomedicine 2018年第8期8卷 418-424页

作者： Sateesh Chandra Gupta Tusha Tripathi Shravan Kumar Paswan Annie G.Agarwal Chandana V.Rao Om P.Sidhu department of phytochemistry CSIR-National Botanical Research Institute department of Pharmacology CSIR-National Botanical Research Institute

Objective: To undertake metabolite profiling of various plant parts of Citrullus colocynthis, and assess antioxidant and wound healing activities of fractions for therapeutical applications. Methods: Extracts from leaves, stem, root, fruit pulp and seeds were analyzed using gas chromatography-mass spectrometry and high performance liquid chromatography. Variation in antioxidant potential was assayed by 1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical scavenging assay. The extract with highest antioxidant potential was subjected on in-vivo wound healing activity using excision wound model. Results: Metabolite profiling of Citrullus colocynthis identified 70 chemically diverse metabolites from different plant parts by using a combination of GC-MS and HPLC. Concentration of colocynthin, a principal active secondary metabolite, ranged from 3.15 mg/g dry weight to 242.00 mg/g dry weight, the lowest being in leaves and highest in fruit pulp. DPPH radical scavenging activity of free radical(IC50) ranged from 196.44 μg/mL in fruit pulp to 413.33 μg/mL in leaves tissues. Significant wound contraction and increase in hydroxyproline content of granulation tissue were observed with ointment formulated from methanolic extract of fruit pulp. Conclusions: The study indicates that the methanol extract of Citrullus colocynthis fruit pulp when applied topically may promote wound contraction in rat model attributable to the accumulation of colocynthin. The high quantity of colocynthin(242.00 mg/g dry weight) and substantial concentration of 2,4-di-tert butyl phenol(3.2%), squalene(4.2%) and δ-tocopherol(2.5%) make this plant to provide new opportunities for development of medicinal, nutraceutical and dietary supplements with optimized functionality.

关键词： Metabolite profiling Citrullus colocynthis GC-MS Antioxidant Wound healing

Models and form factors for stand volume estimation in natural forest ecosystems: a case study of Katarniaghat Wildlife Sanctuary (KGWS), Bahraich District, India

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Journal of Forestry Research 2013年第2期24卷 217-226页

作者： V. A. J Adekunle K. N. Nair A. K. Srivastava N. K. Singh Federal University of Technology Dept of Forestry & Wood Technology National Botanical Research Institute (Council for Scientific & Industrial Research) plant Diversity Systematics & Herbarium Division Rana Pratap Marg department of Forests Sidhauli Forest Division

In view of the difficulties in stand volume estimation in natural forests, we derived real form factors and models for volume estimation in these types of forest ecosystems, using Katarniaghat Wildlife Sanctuary as a case study. Tree growth data were obtained for all trees （dbh 〉10 cm） in 4 plots （25 × 25 m） randomly located in each of three strata selected in the forest. The form factor calculated for the stand was 0.42 and a range of 0.42 0.57 was estimated for selected species （density 〉10）. The parameters of model variables were consistent with general growth trends of trees and each was statistically significant. There was no significant difference （p〉0.05） between the observed and predicted volumes for all models and there was very high correlation between observed and predicted volumes. The output of the performance statistics and the logical signs of the regression coefficients of the models demonstrated that they are useful for volume estimation with minimal error. Plotting the biases with respect to considerable regressor variables showed no meaningful and evident trend of bias values along with the independent variables. This showed that the models did not violate regression assumptions and there were no heteroscedacity or multiculnarity problems. We recommend use of the form factors and models in this ecosystem and in similar ones for stand and tree volume estimation.

关键词： natural forest tree volume Estimation biodiversity tree height forest inventory

Kansuinine J,a new macrocyclic diterpenoid from the roots of Euphorbia kansui

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Chinese Chemical Letters 2010年第8期21卷 943-946页

作者： Jie Guo Xin Fang Ying Tong Di Hui Ming Hua Xiao Jiang Hao department of Natural Products Chemistry Shenyang Pharmaceutical University Shenyang 110016 China State Key Laboratory of phytochemistry and plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

A new macrocyclic diterpenoid,named kansuinine J（1）,was isolated from the roots of Euphorbia *** structure was characterized on the basis of spectroscopic analysis.

关键词： Euphorbia kansui Kansuinine J Macrocyclic diterpenoid

Stereoselectiveα-Glycosylation with GlcN_(3)Donors Enabled Collective Syntheses of Acinetobacter baumannii Capsular Polysaccharides K43,K47 and K88 Repeating Units

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Chinese Journal of Chemistry 2024年第14期42卷 1593-1598页

作者： Kunxiu Shou Shanshan Liu Yunqin Zhang Guozhi Xiao State Key Laboratory of phytochemistry and plant Resources in West China Kunming Institute of BotanyUniversity of Chinese Academy of SciencesChinese Academy of SciencesKunmingYunnan650201 China

Collective syntheses of *** CPS K43,K47 and K88 repeating units have been accomplished via a newα-glycosylation method with GlcN_(3) as donors,which features:1)mild reaction conditions,2)good to high yields,3)excellent *** synthetic route also highlights an orthogonal one-pot coupling strategy on the basis of glycosyl ortho-(1-phenylvinyl)benzoates for stereoselective constructions of both 1,2-trans and 1,2-cis glycosidic bonds,precluding the issues of aglycone transfer.

关键词： A baumanni CPS α-Glycosylation method One-pot glycosylation 1,2-GlcN bonds Glycosyl ortho-(1-phenylvinyl)benzoates Carbohydrates Oligosaccharides Total synthesis