1. School of Pharmacy, Biocenter Kuopio; University of Eastern Finland; P.O. Box 1627 FI 70211 Kuopio Finland
2. School of Pharmacy; University of Eastern Finland; P.O. Box 1627 FI 70211 Kuopio Finland
3. Department of Biology, Natural Product Research Laboratories, Joensuu; University of Eastern Finland; P.O. Box 111 FI 80101 Joensuu Finland
4. Department of Biochemistry; Institute of Soil Science and Plant Cultivation, State Research Institute, ul; Czartoryskich 8 24-100 Pulawy Poland
5. Department of Biology; University of Eastern Finland; P.O. Box 1627 FI 70211 Kuopio Finland