Chemotaxonomic approaches

Hegnauer, R. and Grayer-Barkmeijer, R.J., Relevance of seed polysaccharides and flavonoids for the classification of the Leguminosae a chemotaxonomic approach. Phytochemistry, 34, 3, 1993. 

Schleifer, K.H., Kilpper-Balz, R. (1987). Molecular and Chemotaxonomic Approaches to the Classification of Streptococci, Enterococci and Lactococci A Review. Syst. Appl. Microbiol., 10, 1-19. 

Hofle, M. G. (1988). Identihcation of bacteria by low molecular weight RNA profiles A new chemotaxonomic approach.Microbiol. Methods 8, 235—248. 

Zavarin has continued his chemotaxonomic approach to biogenetic problems with a study of the leaf monoterpenes of some Cupressus species. 

Schleifer KH, Kilpper-Balz R (1984) Transfer of Streptococcus faecalis and Streptococcus faecium to the genus Enterococcus nom. rev. as Enterococcus faecalis comb. nov. and Enterococcus faecium comb. nov. Int J Syst Bacteriol 34 31-34 Schleifer KH, Kilpper-Balz R (1987) Molecular and chemotaxonomic approaches to the classification of streptococci, enterococci and lactococd a review. Syst Appl Microbiol 6 1-19 Semedo T, Santos MA, Lopes MFS, Marques JJF, Crespo MTB, Tenreiro R (2003) Virulence factors in food, chnical and reference enterococci a common trait in the genus Syst Appl Microbiol 26 13-22... 

Four basic approaches are conducted for plant selection for antiviral screening assays 1- Random collection of plants followed by mass screening. 2- Ethnomedical approach. 3- Literature-based follow up of the existing leads. 4- Chemotaxonomic approach [12]. The second and third approaches are the most favored ones because of their cost-effective applicability. The selection based on folkloric use proved five times higher percentage of active leads than other approaches. The random approach usually affords more novel compounds with antiviral activity. Combining ethnomedical, phytochemical and taxonomical approaches is considered the best compromise. 

An understanding of what an alkaloid is will be mentioned in the first section, and in the second section, the aspects of classifying alkaloids on the basis of their biosynthetic origin will be presented. This method will be compared with a classification based on their carbon or heterocyclic skeleton, such as indole, isoquinoline alkaloids, or a classification of the alkaloids based on a chemotaxonomic approach, such as Rutaceae and Apocynaceae alkaloids. A short history of the study of alkaloids and the crude drugs as the origin of various alkaloids, and their relevance in the history of natural products chemistry will be described. Through these discussions, it will be established that the natural products classified as alkaloids relate to our life deeply, and on an everyday basis, as medicines, as dyestuffs, as flavors, as stimulants, and as toxic substances. 

Compounds obtained from natural sources have always contributed to the development of small molecules for various targets in the history of medicinal chemistry. Recently, several small molecules derived from natural products have been shown to possess Icmt inhibitory activity [72,73]. This effort to discover other natural product inhibitors of Icmt utilized a HTS approach. Of the approximately 6 x 10 extracts screened, the extract from the order Verongida displayed Icmt inhibition. A bromotyrosine-derived chemotaxonomic marker characterizes marine sponges in this order. The extract from Pseudoceratina sp. contained a compound with a bromotyrosyl-spermine-bromotyrosyl sequence, named spermatinamine... 

Monomethyl and dimethylalkanes in the range C16-C20 are prominent in many cultured cyanobacteria as well as most cyanobacterial mat communities that have been studied (Section 8.03.5.3). No specific physiological role has been assigned to these hydrocarbons. Because they have probably multiple origins in ancient sediments and petroleum, these monomethyl and dimethylalkanes alone probably have limited chemotaxonomic specificity. However, they may be very useful in multivariate approaches for linking isotopic and molecular-structure data for a less ambiguous identification of sedimentary cyanobacterial lipids. 

Several strategies and philosophies are available for the identification of bioactive compounds from natural sources. Different aspects of these strategies have been reviewed [44-47]. Several such approaches have been used previously for this purpose 1) ethnobotany, 2) serendipity, 3) random sampling, and 4) exploitation of chemotaxonomic knowledge. 

Former chemotaxonomic studies often emphasized that not the presence of a compound itself, but the biosynthetic processes, the potential of a plant for the formation of the given compound can be taken into account. According to the present knowledge, this general de nition seems to be oversimpli ed and not fully adequate any more. Today, we have to face two approaches of chemotaxonomic considerations. 

Classification and identification of microorganisms based on rapid and specific methods for determining the chemical composition have proved to be a valuable approach in microbiology. The identification of many chemical constituents that show a degree of specificity suitable for chemotaxonomic and/or diagnostic purposes made it clear that improvements in methods of sample preparation play an important role in fully utilizing the high speed and specificity offered by MS. 

For the application of both culture-dependent and culture-independent approaches, molecular, phenotypic, and chemotaxonomic data have allowed researchers the unequivocal identification of AAB from many varieties of traditional and industrial vinegar niches (SF and SC acetifications) as well as the classification of new isolates (Cleenwerck and de Vos 2008 Yamada and Yukphan 2008 De Veto et al. 2006 Gullo et al. 2009). 

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