Sumu Matsueda

Bio: Sumu Matsueda is an academic researcher from University of California, Los Angeles. The author has contributed to research in topics: Artemisia & Artemisia douglasiana. The author has an hindex of 4, co-authored 4 publications receiving 67 citations.

Sesquiterpene lactones as taxonomic characters in the asteraceae

Abstract: The Asteraceae is characterized by structurally diverse sesquiterpene lactones and furanosesquiterpenes. In this review the tribal, subtribal and generic distribution of sesquiterpene lactones is examined and the compounds’ utility as taxonomic characters discussed. Sesquiterpene lactones fulfill the major requirements for good analytic and synthetic characters. Studies of infraspecific sesquiterpene lactone variation indicate that different elements within complex taxa are often defined by distinct chemistries, termed chemotypes. Chemotypes have been identified within many of the thoroughly investigated taxa:Ambrosia camphorata, A. chamissonis, A. confertiflora, theA. cumanensis-A. psilostachya-A. artemisiifolia complex,A. dumosa, Artemisia tridentata, Gaillardia pulchella andMelampodium leucanthum. Such an analytic usage is mostly restricted to the infraspecific level. Synthetic usage at the interspecific level and above profits from the application of a biogenetically based methodology for sorting out the complex molecules’ carbon-skeletal and substitutional features into unit characters. Cladistics or Hennigian phylogenetic systematics provides a useful framework for such an analysis. Preliminary surveys indicate that sesquiterpene lactones are especially good characters for differentiating subtribes within several major tribes: the Vernonieae, Heliantheae and Mutisieae. As yet, too few data are available for other tribes to discern such patterns. Species surveys inVernonia, Ambrosia, Iva, Parthenium,Tetragonotheca andArtemisia demonstrate that sesquiterpene lactones are useful in discerning infrageneric groups. The biogenetic cladistic analysis of the interspecific sesquiterpene lactone variation inIva shows the efficacy of this analytical methodology. At present, such biogenetically based approaches are impeded by limited biosynthetic evidence and the erratic distribution of sesquiterpene lactones within the family. Instances of apparent displacement of sesquiterpene lactones by other terpenoids (i.e. sesquiterpene furans, alcohols and acids, diterpenes, diterpene acids, etc.) at various taxonomic levels suggest that ultimately sesquiterpene lactones must be interpreted as taxonomic characters in the context of the family’s total terpene chemistry. All taxa from which sesquiterpene lactones have been reported are listed together with the compound names, major structural features and the literature cited. A less-complete listing is provided for taxa producing furanosesquiterpenes. Structures for all reported compounds are included. Two appendices listing alphabetically taxa and compounds and relevant text page numbers permit cross-indexing of plants and compounds.

Mediterranean Type Ecosystems

Abstract: The fossil record indicates that species similar to most woody plants that now make up the sclerophyllous mixed evergreen forest, oak woodland-savanna, and chaparral vegetation of California were in existence during Miocene time, and that the Neogene vegetation types were more diverse in taxa and adaptive types than the modern descendant vegetation. The plants lived under warm to mild temperate climates with ample summer rainfall. Commencing in the later Miocene, the subtropical high pressure system strengthened as the oceans became colder and the lands hotter. As the thermal contrast increased, summer precipitation was reduced and many taxa were eliminated from the woody flora which decreased in diversity. Hence, most of the surviving woody plants, and the adaptive types they represent, are much older than mediterranean climate which only appeared after the early Pleistocene. It was primarily the herbaceous flora that evolved under mediterranean climate, though a few woody genera also responded. Rapid proliferation of species resulted because intense, continuing mountain building established many new topographic-climatic-

Antimycobacterial plant terpenoids.

Abstract: Tuberculosis (TB), mainly caused by Mycobacterium tuberculosis, is the leading killer among all infectious diseases worldwide and is responsible for more than two million deaths annually. For over thirty years no antitubercular agents with new mechanisms of action have been developed. The recent in­ crease in the number of multi-drug resistant clinical isolates of M. tuberculosis has created an urgent need for the discovery and development of new antituberculosis leads. This review covers recent reports on plant-derived terpenoids that have demonstrated moderate to high activity in in vitro bioassays against M. tuberculosis. In this review, mono-, sesqui-, di- and triterpenes, and sterols, their structural analogs and semisyn­ thetic derivatives will be discussed, with particular emphasis on the structural features essential for anti mycobacterial activity.

Antileishmanial Activity of Parthenolide, a Sesquiterpene Lactone Isolated from Tanacetum parthenium

Abstract: The in vitro activity of parthenolide against Leishmania amazonensis was investigated. Parthenolide is a sesquiterpene lactone purified from the hydroalcoholic extract of aerial parts of Tanacetum parthenium. This isolated compound was identified through spectral analyses by UV, infrared, (1)H and (13)C nuclear magnetic resonance imaging, DEPT (distortionless enhancement by polarization transfer), COSY (correlated spectroscopy), HMQC (heteronuclear multiple-quantum coherence), and electron spray ionization-mass spectrometry. Parthenolide showed significant activity against the promastigote form of L. amazonensis, with 50% inhibition of cell growth at a concentration of 0.37 microg/ml. For the intracellular amastigote form, parthenolide reduced by 50% the survival index of parasites in macrophages when it was used at 0.81 microg/ml. The purified compound showed no cytotoxic effects against J774G8 macrophages in culture and did not cause lysis in sheep blood when it was used at higher concentrations that inhibited promastigote forms. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis with gelatin as the substrate showed that the enzymatic activity of the enzyme cysteine protease increased following treatment of the promastigotes with the isolated compound. This finding was correlated with marked morphological changes induced by parthenolide, such as the appearance of structures similar to large lysosomes and intense exocytic activity in the region of the flagellar pocket, as seen by electron microscopy. These results provide new perspectives on the development of novel drugs with leishmanicidal activities obtained from natural products.

The effects of hybridization in plants on secondary chemistry: implications for the ecology and evolution of plant-herbivore interactions.

Abstract: Natural hybridization is a frequent phenomenon in plants It can lead to the formation of new species, facilitate introgression of plant traits, and affect the interactions between plants and their biotic and abiotic environments An important consequence of hybridization is the generation of qualitative and quantitative variation in secondary chemistry Using the literature and my own results, I review the effects of hybridization on plant secondary chemistry, the mechanisms that generate patterns of chemical variation, and the possible consequences of this variation for plants and herbivores Hybrids are immensely variable Qualitatively, hybrids may express all of the secondary chemicals of the parental taxa, may fail to express certain parental chemicals, or may express novel chemicals that are absent in each parent Quantitatively, concentrations of parental chemicals may vary markedly among hybrids There are five primary factors that contribute to variation: parental taxa, hybrid class (F(1), F(2), etc), ploidy level, chemical class, and the genetics of expression (dominance, recessive vs additive inheritance) This variation is likely to affect the process of chemical diversification, the potential for introgression, the likelihood that hybrids will facilitate host shifts by herbivores, and the conditions that might lead to enhanced hybrid susceptibility and lower fitness