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Volume 46, Number 6
(November - December 2001) |
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Volume 46, Number 6
(November - December 2001) |
Influence of the Extraction Mode on the Yield of Taxoids from Yew Tissues - Preliminary Experiments
by Michal M. Hajnos1, Monika Waksmundzka-Hajnos2, Jan Gawdzik3, Andrzej L. Dawidowicz3 and Kazimierz Glowniak1
1Department
of Pharmacognosy, Medical University, 12 Peowiaków Street, 20-007
Lublin, Poland
2Department
of Inorganic and Analytical Chemistry, Mdical University, 6 Staszica Street,
20-081 Lublin, Poland
3Department
of Chemical Phisics and Physicochemical Separation Methods, Faculty of
Chemistry, Maria Curie-Sklodowska University, 3 M.C.-Sklodowskiej Square,
20-031 Lublin, Poland
Key words: taxus species, paclitaxel, cephalomannine, taxoid, ASE, maceration, ultrasonic extraction, RP HPLC analysis
Different modes of extraction of yew twings, such as: maceration with
methanol at room temperature, extraction with methanol in ultrasonic bath
at room temperature, accelerated solvent extraction with methanol at room
temperature and at 1000C were compared. The effect of pre-extraction with
n-hexane in accelerated solvent extraction (ASE) method was also investigated.
The following procedure, before the RP-HPLC analysis of taxoids, was perfomed:
SPE of crude extracts dissolved in dichloromethane using alumina colum
and elution with dichloromethane-ethyl acetate-methanol in different proportions
followed by zonal micropreparative TLC using 0.5 mm layer of silica and
elution with multicomponent eluent. The fractions were analysed quantitatively
using C18 column and acetonitrile-water
(1 : 1, v/v) mixtures as eluent. The obtained results presented graphically
allow to conclude that the best yield of extraction was obtained by ASE
method, when methanol at 100 oC was used
as an extrahent. Comparable results were obtained using extraction in ultrasonic
bath with methanol at room temperature.
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