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Comparison of Some Chemical Constituents of The COMPARISON OF SOME CHEMICAL CONSTITUENTS OF THE LYCOPODS by ELEANOR ELIZABETH McMULLAN B.Sc, University of British Columbia, 1963 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in the Department of Biology and Botany We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA August, 1966 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely avail able for reference and study, I further agree that permission-for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or by his representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. i i ABSTRACT A survey of some chemical constituents of the lycopods was carried out in order to determine whether the chemistry of these plants is cor• related with their taxonomy. One approach to this problem was to study the products of photosynthesis of species of Lycopodium. Selaginella and Isoetes. Radioactive C^0£ was to -hese plants and the distribution of radioactivity in sugars and amino acids was examined by means of paper chromatography. The distribution of radioactivity in sugars was characteristic for each genus, but the distribution of radioactivity in amino acids was not. In Selaginella 80% or more of the radioactivity was incorporated into trehalose while most of the rest of the radioactivity was found in sucrose. There was one exception to this: in S. kraussiana 40% of radioactivity was incorporated into trehalose while most of the rest was incorporated into an unidentified sugar. In Isoetes k% to 8% of the radioactivity was found in trehalose with most of the rest in sucrose. In Lycopodiurn 95% or more of the radioactivity was found in sucrose and none was found in trehalose. Radioactive trehalose was administered to species of these genera and it was shown that they are all able to metabolize trehalose to some degree. Species of Selaginella. Isoetes and Phylloglossum were examined to determine whether they contain alkaloids. Phylloglossum extracts contained compounds with the chromatographic properties of Lycopodiurn alkaloids, but Selaginella and Isoetes species did not contain detectable amounts of these compounds. TABLE OF CONTENTS Page INTRODUCTION 1 REVIEW OF SUBJECT 1 Morphology and Taxonomy 1 Chemistry 8 (i) General Considerations 8 (ii) Chemistry of the Lycopods 16 METHODS AND MATERIALS 31 1. Sources of Plant Material 31 2. Preparation of Aqueous Extracts 31 3. Preparation of Neutral Cation, and Anion Fractions of Plant Extracts 31 k. Preparation of Alkaloid Extracts 35 5. Methyl at ion of Sugars 35 6. Vapour Phase Chromatography 36 7. One Directional Paper Chromatography of Sugars for Qualita• tive Analysis 36 8. One Directional Paper Chromatography of Sugars for Prepara• tive Isolation 37 9. One Directional Paper Chromatography of Alkaloids 37 10. Two Directional Chromatography of Sugars and Amino Acids 37 11. Thin Layer Chromatography of Alkaloids 38 12. Column Chromatography of Sugars 39 13. Detection of Spots 39 14. Technique for Administering c'^0, 40 iv TABLE OF CONTENTS, cont'd. Page METHODS AND MATERIALS, cont'd. 15. Technique for Administering Trehalose-c'^ hi 16. Measurement of Radioactivity hi EXPERIMENTAL AND RESULTS hh 1. Vapour Phase Chromatography hh 2. Preliminary Survey of the Sugars of Lycopodiurn and Selaginella hh 3. Survey of the Distribution of Radioactivity in Sugars and Amino Acids of Lycopods Fed C'^O- hh h. Isolation of Radioactive Trehalose 48 1h 5. Administration of Trehalose-C to Plants 55 6. Examination of Selaginella, Isoetes and Phylloglossum for the Presence of Alkaloids 58 DISCUSSION 1. Use of Vapour Phase Chromatography for Quantitative Surveys of Sugars in Plants 60 2. Survey of the Metabolic Activity of Sugars and Amino Acids in Lycopods as Indicated by C1^ Incorporation 62 3. Survey of Lycopods for the Presence of Alkaloids 67 BIBLIOGRAPHY 69 SUMMARY 7h APPENDIX 76 LIST OF TABLES Table Page I Sources of Plant Material 32 II Preliminary Survey of Sugars in Lycopodiurn and Selaqinella 47 III Distribution of Radioactivity in the Neutral Aqueous Extract of Plants Fed 49 IV Distribution of Radioactivity in the Cation Fraction of Aqueous Extract of Plants Fed C^02 51 V Distribution of Radioactivity in Trehalose, Sucrose, Glucose and Fructose from Plants Administered Trehalose-Cl^ 57 vi LIST OF FIGURES Figure Page 1 Trehalose 17 2 Lycopodine 22 3 Lyconnotine 23 k Annotinine 23 5 Lycodine 2k 6 Selagine 2k 7 Cernuine, Lycocernuine, and Suggested Precursors 25 8 Biosynthesis of Annotinine Suggested by Leete 26 9 Biosynthesis of Quinolizidine Skeleton 27 10 Biosynthesis of Four Basic Skeletons of Lycopodiurn Alkaloids Suggested by Conroy 28 11 Biosynthesis of Annotinine Suggested by Ayer et al_. 30 12 Apparatus for Administering k\ 13 Vapour Phase Chromatography of Mixtures of Methylated Sucrose and Trehalose kS \k Radioautographs Showing Distribution of Radioactivity in Sugars in Representative Chromatograms 5k 15 1. Infra-red Spectrum of Crystals Obtained from Selaginella wallacei 2. Infra-red Spectrum of Trehalose 56 16 Chromatogram of Alkaloids from Extracts of 1 gm of Plant Material 59 17 Chromatogram of Alkaloids from Extracts of 1 gm of Plant Material 59 18 Chromatogram of Alkaloids from Extracts of 2 1/2 gm of Plant Material 61 VI I LIST OF FIGURES, cont'd. Figure Page 19 Representative Graph of C02 Concentration in Air Stream During C^0_ Feedings 64 20 Representative Graph of Radioactivity in Air Stream l During C ^02 Feedings 64 21 Dioxane Quenched Standards Efficiency versus Channels Ratio 77 i vi i i ACKNOWLEDGMENTS I am very grateful to Dr. G.H.N. Towers for his assistance and advice in the preparation of this thesis. I would also like to thank Dr. E.B. Tregunna for instruction in the use of radioisotopes, Dr. W.B. Schofield for his criticism of the section dealing with morphology, Dr. T.M.C. Taylor, Dr. V.J. Krajina, and Dr. W.B. Schofield for their assistance in identifying collections, and Dr. T. Bisalputra and Miss Nancy Corfman for the use of their photographic equipment. I wish to thank Mrs. Aida Tse for the infra-red spectra, and Mr. D.E. McMullan, Mr. L.K. Wade, Dr. R.C. Brooke, Mr. T. Flegel, Mr. L. Cordes, and Mr. G. Davis for their collections. 1 INTRODUCTION The extant members of the lycopods are remnants of a group of plants whose history extends back at least to the Devonian, some 50 million years before the conifers appeared and 300 million years before the angio- sperms (60). They have characteristics in common with each other and with fossilized members of the division which suggest that they have common ancestors. However, there are marked dissimilarities among some of them, implying that they have been evolving separately for a very long time. The five living genera are placed in three different orders reflecting these evolutionary lines. Some chemical constituents of these genera were surveyed in an attempt to discover whether metabolic peculiarities had arisen over this long period of evolution, and to assess the diagnostic value of these changes. REVIEW OF THE SUBJECT Morphology and Taxonomy The lycopods are distinct from the ferns, with which they were once classified, in their leaves, position of sporangia, type of branching, the gametophytes. Their leaves are microphylls, generally small and al• ways supplied by a single vein which lacks a leaf gap in the stem. Even before the lycopods were recognized as a division separate from the ferns, The classification outlined in Scagel et_ al. (49) will be followed. The plant kingdom is given twelve divisions, including Psilophyta, Lycopodophyta, Arthrophyta and Pterophyta for the former Pteridophyta. 2 microphylls were thought to have a different phylogenetic origin from the megaphylls of ferns, having developed as stem enations while megaphylls developed from a specialized branch system (50). The sporangia of lycopods are borne singly on the adaxial side of a leaf or laterally on the stem but not in aggregates on the leaf margin or on the underside as they are in the ferns. Sporophylls are often localized at the ends of branches to form strobili, structures which do not occur in ferns. Branching of the stem is dichotomous with transitions to lateral branching brought about by unequal growth of the branches. This situation is considered primitive to that in the ferns where lateral branches arise in leaf axils as a rule, though there may be reversion to dichotomous branching. The relation of a branch to a particular leaf does not occur in the lycopods except in some dorsiventral Selaginella species, where it apparently arose secondarily as a result of the factors that caused dorsi• ventral ity (50). The gametophytes of the lycopods are simpler than those of ferns. In the Selaginellales and Isoetales the gametophytes develop largely within the spore wall, on nutritive substances deposited in the spore from the sporophyte (50). In the Lycopodiales the gametophyte germinates exosporally but is smaller than a fern gametophyte and frequently lacks chlorophyll. The morphology of these gametophytes seems to be related to their development; in one species if the spore germinates above ground it produces a carrot-shaped green gametophyte, but if the gametophyte develops underground it is colourless and cylindrical. Apparently all gametophytes in the Lycopodiales have a mycorrhizal association (52). The differences 3 between lycopod and fern gametophytes are not as important phylogenetic- ally as the sporophytic differences discussed, since reduction and loss of chlorophyll in gametophytes are known in fern genera (e.g. Botrychium. Qphioglossum) and since heterospory has arisen independently in more than one group of plants (20).
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