The doctoral thesis is focused on isolation of Schisandra
chinensis dibenzo[a,c]cyclooctadiene lignans using high
performance liquid chromatography. This thesis is engaged in
optimalisation of methanolic extraction of the sample and the
determination of lignans of Schisandra chinensis cell cultures.
   Schisandra chinensis is a well-known medicinal plant in
traditional Chinese medicine. The fruits and seeds from this
plant have been used for centuries as a tonic and antitussive. 
The active ingredients are lignans possessing an unusual
structure derived from dibenzo[a,c]cyclooctadiene. These
lignans have been shown to possess a broad range of biological
effects, including anti-oxidative and hepatoprotective,
antiproliferative properties and antivirus activity.
	    To obtain pure lignans, 349 g of Schisandra
chinensis seeds were extracted with petroleum ether. The
fraction rich in lignans was obtained by extraction of
petroleum ether fraction with methanol. Methanol extract was
fractionated on silica gel column and subsequently by
semipreparative high performance liquid chromatography on
reversed phase columns. Eight lignans - schizandrin, gomisin A,
deoxyschizandrin, γ-schizandrin and minor lignans
tigloylgomisin H, tigloylgomisin P, angeloylgomisin H and
gomisin J were isolated.
We have attempted to develop a simple and rapid method for
quantitative analysis of lignans in cell cultures, liquid media
of S. chinensis and added polymeric resins. The method of
determination of lignans was optimized in these steps: the
choice of an organic solvent for extraction of cell cultures, a
solid phase extraction (SPE) and HPLC analysis. Methanol was
found to be the most efficient solvent for the extraction of
lignans. The samples were tree times extracted with 5 ml of
methanol using an orbital shaker set at 120 rpm, 45 ºC, twice
for 3 hours and again for 6 hours. Methanolic extracts were
used to clean-up the samples by the help of solid phase
extraction (SPE). The extracts were re-dissolved in 2 ml of a
mixture of methanol and deionized water (1:9, v/v) and loaded
onto the cartridges, which were washed with 2 ml of a mixture
of methanol and deionized water (4:6, v/v). Lignans were eluted
with 2 ml of methanol. With this amount of methanol is washed
99.5 % of all lignans loaded onto the cartridge. The
chromatographic separation was carried out on Chromolith
Performance RP-18e monolith column (100 x 4.6 mm, Merck) using
isocratic mobile phase of acetonitrile and water in the ratio
50:50 (v/v) at a flow rate of 2.0 ml/min. Lignans were
determined by the UV detection. The UV detector was set at 220
nm.
Another aim of this thesis was the determination of the content
of lignans from Schisandra chinensis cultures with addition of
elicitors and polymeric resins from polystyrene (Amberlite
XAD-2) and from polyakrylester (Amberlite XAD-7). The cell
cultures were cultivated at Department of Plant Biology,
Faculty of Agronomy, Mendel University of Agriculture and
Forestry Brno. Results described in this work shows, that the
addition of polymeric resins, particularly nonpolar Amberlite
XAD-2 can be a very effective tool for releasing lignans into
extracellular compartment and for increasing lignan production
in S. chinensis culture. Amberlite XAD-2 adsorbed and increased
especially total production of deoxyschizandrin. Amberlite
XAD-7 enhanced the amount of wuweizisu C in some cell lines.
Lignans adsorbed on polymeric resins can be easily recovered
and purified without destruction of the cells. This is the
advantage of this method, because the cell cultures grow is
relatively slowly.