Genera, Review

This chapter summarizes the present state of the art of the forced hydrolysis approach by considering specific cations, particularly those of greatest practical and theoretical interest, using aqueous solutions of common salts. In addition to being economical in the manufacture of different products, the described procedure can also help in the development of a better understanding of different processes, such as corrosion of metals or formation of minerals, to mention a few. It should be emphasized that the focus of this chapter is on dispersions of narrow particle size distributions, normally designated as monodispersed systems. While a number of genera reviews have been published on monodispersed colloids (7,9-21), this chapter specifically addresses the problems related to metal (hydrous) oxides. 

Euw, J., M. Lounasmaa, T. Reichstein, and C.-J. Widen Chemotaxonomy in Dryopteris and Related Genera. Review and Evaluation of Analytical Methods. Studia Geobotanica (Trieste) 1, 275 (1980). 

AG type II is most abundant in the heartwood of the genus Larix and occurs as minor, water-soluble components in softwoods. Certain tree parts of western larch (I. occidentalis) were reported to contain up to 35% AG [378]. The polysaccharide is located in the lumen of the tracheids and ray cells. Consequently, it is not a cell-wall component and, by definition, not a true hemicellulose. However, it is commonly classified as such in the field of wood and pulping research. This motivated us to include the larch AG in the review. 

Phlomis consists of about 100 species, a dozen of which occur in Mediterranean Europe (Mabberley, 1997, p. 549). The study of interest here involves a study of the flavonoids of R lychnitys L., a small plant native to Mediterranean Spain (Tomas et ah, 1986). Those workers identified the common flavones apigenin, luteolin, and luteolin 3 -methyl ether (chrysoeriol) 7-0-glucosides and their respective /7-coumaroyl derivatives. A brief review of the literature revealed that Mediterranean species of Phlomis are characterized by the presence of the flavone methyl ether, whereas continental species appear to lack 0-methylated flavones. Species from India have been reported to lack flavones but accumulate flavonols. The suggestion was made that accumulation of flavonols represents an ancestral feature of the genus. 

Baumann, P., Baumann, L., Lai, C.Y., Rouhbakhsh, D., Moran, N.A. and Clark, M.A. (1995) Genetics, physiology, and evolutionary relationships of the genus Buchnercv. intracellular symbionts of aphids. Annual Review of Microbiology 49, 55-94. 

Other reviews related to this contribution should also be mentioned, in addition to the chapters of this series, which we shall recall later. Some of these deal in general with the problem of classification of indole alkaloids and with chemo-taxonomic investigation (7-5). The chemistry of indole alkaloids is included in the Royal Society of Chemistry s Specialist Periodical Reports and has been extensively reviewed in a one-volume survey edited by J. E. Saxton (6), presenting a reasonably complete, although not exhaustive, picture of the state of the art. Other books on indole alkaloid chemistry treating this area cursorily should also be mentioned (7, 8). Recently, the genus Tabernaemontana was excellently reviewed, particularly with respect to taxonomy, phytochemistry, ethnobotany, and pharmacology (9). 

The batrachotoxins were the first class of unique alkaloids to be characterized from skin extracts of frogs of the family Dendrobatidae (see ref. 23 for a review of amphibian alkaloids). Batrachotoxin was detected in only five species of dendrobatid frogs and these frogs were then classified as the monophyletic genus Phyllobates, based in part on the presence of batrachotoxins (24). However, levels of batrachotoxins differ considerably, with the Colombian Phyllobates terribilis containing nearly 1 mg of batrachotoxins per frog, while the somewhat smaller Phyllobates bicolor and Phyllobates aurotaenia, also from the rain forests of the Pacific versant in Colombia, contain 10-fold lower skin levels (8). The two... 

Longstaff, B.C. 1981. Biology of the grain pest species of the genus Sitophilus (Coleoptera Curculio-nidae) A critical review. Protect. Ecol. 2, 83-130. 

The genus Enteromorpha was recently synonymized with the genus Ulva (Hayden et al. 2003). Throughout this review, species that were formerly called Enteromorpha will be referred to as Ulva, regardless of how they were named in the original reference. 

The venom of ants of the genus Myrmicaria is made up of indolizidine or pyrrole-indolizidine alkaloids [188,189]. The synthesis of some of these alkaloids has already been reported in the review of Leclercq et al. [114]. Thus, we will report here only on the syntheses published since 1999. 

Pederin (104), the powerful cytotoxin of staphylinid beetles of the genus Paederus, has been the object of renewed interest due to the unexpected discovery of a series of closely related compounds in marine sponges that display antitumor activities. The latter, as well as pederin, were prepared by total synthesis and their biological activities were reported [219,220]. A recent review summarizing present knowledge on this family of compounds has been published [221]. 

The most thoroughly investigated representatives are the pyoverdins, also spelled pyoverdines and occasionally named pseudobactins 353), produced by the fluorescent members of the genus Pseudomonas. For reviews see 44, 231) for a detailed... 

Before a species is analyzed with respect to its flavonoid content, knowledge about earlier reports on the chemistry and flavonoid distribution within the genus and related species may be of value. The most exhaustive source for such information is Chemical Abstracts, and excellent reviews on structures and distribution of flavanoids have been compiled regularly.Several reviews have recently addressed the general field of flavonoid analysis.Among the earlier reviews in the field, we will particularly recommend consulting Techniques of Flavonoid Identification by Markham and Plant Phenolics by Harborne. References to review articles on specific spectroscopic techniques applied on flavonoids will be cited under the various spectroscopic methods covered in this chapter. Spectroscopic information of importance is also presented in several other chapters in this book. 

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