نتایج جستجو برای: triterpene mass fragmentation pattern

تعداد نتایج: 842418  

Journal: :Marine Drugs 2008
Beatriz Paz Antonio H. Daranas Patricia G. Cruz José M. Franco Manuel Norte José J. Fernández

Okadaic acid (1) (OA) and its congeners are mainly responsible for diarrhetic shellfish poisoning (DSP) syndrome. The presence of several OA derivatives have already been confirmed in Prorocentrum and Dinophysis spp. In this paper, we report on the detection and identification of a new DSP toxin, the OA isomer 19-epi-okadaic acid (2) (19-epi-OA), isolated from cultures of Prorocentrum belizeanu...

Journal: :Molecules 2014
Indra Prakash Venkata Sai Prakash Chaturvedula

Continuous phytochemical studies of the crude extract of Luo Han Guo (Siraitia grosvenorii) furnished three additional new cucurbitane triterpene glycosides, namely 11-deoxymogroside V, 11-deoxyisomogroside V, and 11-deoxymogroside VI. The structures of all the isolated compounds were characterized on the basis of extensive NMR and mass spectral data as well as hydrolysis studies. The complete ...

Journal: :Bioscience, biotechnology, and biochemistry 2003
Masahiro Nagase Jinsei Oto Sin Sugiyama Kouichi Yube Yoshihisa Takaishi Nobuo Sakato

Celastrol, which is a triterpene purified from Celastraceae plants, has anticancer and anti-inflammatory activities. In this study we investigated to clarify whether celastrol can induce apoptosis in a human leukemia HL-60 model system. Celastrol was found to induce apoptosis, and the rank order of the potency of celastrol and its derivatives to induce internucleosomal DNA fragmentation was fou...

Journal: :Journal of pharmaceutical and biomedical analysis 2011
Bharathi Avula Yan-Hong Wang Chidananda Swamy Rumalla Zulfiqar Ali Troy J Smillie Ikhlas A Khan

Analytical methods including HPLC, UPLC and HPTLC are presented for the determination of major alkaloid and triterpene saponins from the roots of Caulophyllum thalictroides (L.) Michx. (blue cohosh) and dietary supplements claiming to contain blue cohosh. A separation by LC was achieved using a reversed phase column, PDA with ELS detection, and ammonium acetate/acetonitrile gradient as the mobi...

2012
Karl L. Reichelt Dag Tveiten Anne-Mari Knivsberg Gunnar Brønstad

PROBLEM The nature of the peptides found increased in urine from autism needs verification of their structure, especially those that show opioid activity. METHODS The peptides were separated on reverse phase C-18 HPLC in Trifluoroacetic acid-acetonitril gradients. Peaks eluting where synthetic opioids appear, and peaks that are common to most autistic children were analyzed by mass spectromet...

Journal: :Bosnian journal of basic medical sciences 2009
Elvira E Kovac-Besović Kemal Durić Zdenka Kalodera Emin Sofić

Betulae cortex, Betula pendula Roth., Betulaceae, comprise triterpene substances which are confirmed to posses very important pharmacological activities such as anti-inflammatory, anticancer and antiviral. In this study, extraction of triterpene substances from both, inner and external birch bark was carried out and after that qualitative analysis on betulin, betulinic acid, oleanolic acid and ...

Journal: :physical chemistry research 0
bahman farajmand chemistry department, university of zanjan, zanjan 45371-38791, iran hamed bahrami chemistry department, university of zanjan, zanjan , iran

the present study describes the fragmentation under electron ionization (ei) of gas phase serine and threonine amino acids. ab initio methods were performed to calculate the fragmentation paths and interpret the mass spectra. the six lowest energy conformers of l-serine, l-threonine and l-allo-threonine were obtained with b3lyp, g3mp2 and mp2 methods. the adiabatic and vertical ionization energ...

Journal: :Molecules 2010
Tatiane C de Carvalho Aline M Polizeli Izabel C C Turatti Marcela E Severiano Carlos E de Carvalho Sérgio R Ambrósio Antônio E M Crotti Uir S de Figueiredo Paulo C Vieira Niege A J C Furtado

The goal of the study was to evaluate the ability of filamentous fungi to biotransform the pentacyclic triterpene lupeol. The microbial transformations were carried out in shake flasks in different media. Experiments were also run with control flasks. Samples of each culture were taken every 24 hours, extracted with ethyl acetate, and analyzed by GC-MS. The biotransformation of lupeol by Asperg...

Journal: :Zeitschrift fur Naturforschung. C, Journal of biosciences 2003
Maya Mitova Rilka Taskova Simeon Popov Ralf Günter Berger Ulrich Krings Nedjalka Handjieva

Sterols, triterpenes, volatiles, polar and other constituents in aerial parts of Carthamus lanatus were analyzed by gas chromatography-mass spectrometry. Over 90 compounds were identified most of them new for the species. Sitosterol and stigmasterol were the most abundant of 10 sterols identified in the sterol fraction. Taraxasterol, alpha- and beta-amyrine prevailed in the triterpene fraction....

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