Extraction and Planar Chromatographic Separation Techniques in the

8. EXPERIMENTAL
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A detailed presentation of the materials and methods can be found in the original publications.
8.1. Materials
8.1.1.Standard compounds
The standard compounds used in the individual studies are presented in Table 2. The indole
derivatives (IV) were used as 0.5 mg/ml solutions in methanol. The phenolic acids (V) and
flavonoids (V) were used as 0.5 mg/ml solutions in methanol, except for (±)-catechin (V)
which was used as a 1.0 mg/ml solution and ellagic acid (V) which was used as an 0.2 mg/ml
solution, both in methanol. Of the three coumarins studied, herniarin (V) was used as a 50
µg/ml solution, scopoletin (V) as a 25 µg/ml solution and umbelliferone (V) as a 10 µg/ml
solution in methanol. For the measurement of the free radical scavenging activity the standard
solutions of the phenolic compounds were prepared to a concentration of 20 mM in methanol,
except for ellagic acid which was dissolved in DMSO (VI).
8.1.2.Plant material
Ficus sycomorus L. and F. bengalensis L. were grown in the fields of the Faculty of
Agriculture, Cairo University, Cairo, Egypt. The material was identified by B. El-Dewan
(senior research scientist, Ministry of Agriculture, Cairo, Egypt). The leaves were air-dried
and kept in a paper sack in a dry, dark and cool place and then transferred to the Division of
Pharmacognosy, Department of Pharmacy, University of Helsinki (I). The ground and airdried
onion, Allium cepa L., was imported from California, USA by Paulig Group Ltd.,
Helsinki (II). Floral stems and leaves of Gerbera hybrida were collected from a greenhouse in
Viikki, Helsinki. The plant material was freeze-dried and stored in plastic bags at -20ºC. The
material was ground and sieved prior to extraction (III). Leaves of Phyllanthus emblica L.
were collected from a wild tree close to the beach of Teluk Bahang, Penang Island, Malaysia.
The plant was identified by Dr. Mashhor Mansor (School of Biological Sciences, Universiti
Sains Malaysia, Penang, Malaysia), and a voucher specimen was deposited in the herbarium
of the School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia. The
leaves with their petioles were oven dried at 40°C for 48 hours and kept in paper sacks in dry
and dark conditions at room temperature until used (V). The rapeseed meal used in the radical
scavenging activity tests was obtained from the companies Mildola Ltd. and Raisio Group Ltd
(VI).