Secondary metabolites occurrence

Crozier, A., Clifford, M. N., and Ashihara, H. (2006). Plant Secondary Metabolites Occurrence, Structure and Role in the Human Diet. Blackwell Publishing Ltd., Oxford, UK. 

Crozier A, Clifford MN, Ashihara H (eds) (2008) Plant secondary metabolites occurrence, structure and role in the human diet. Blackwell Publishing Ltd, Oxford... 

Crozier A, Yokota T, Jaganath IB, Marks S, Saltmarsh M, Clifford MN (2006) Secondary metabolites in fiiiits, vegetables, beverages and other plant-based dietary components. In Crozier A, Clifford MN, Ashdiara H (eds) Plant secondary metabolites occurrence, structure and role in the human diet. Blackwell, Oxford, UK... 

The occurrence in some plants of secondary metabolites characterized by an 0-heterocyclic structure and exhibiting antimicrobial properties is a well-known phenomenon [2,8-10]. Among them, catechins and proanthocyanidins are two classes of compounds exhibiting antimicrobial properties towards both prokaryotic and eukaryotic microorganisms. Yet, despite the large number of studies published so far, the real potentialities and limitations given by the use of this class of molecules as antiviral or antimicrobial (antibacterial, antimycotic, antiprotozoal) agents have not been critically evaluated. The present chapter represents an overview of the re-... 

The term, complex tannin, appears to be established as descriptor for the class of polyphenols in which a flavan-3-ol unit, representing a constituent unit of the condensed tannins (proanthocyanidins), is connected to a hydrolyzable (gallo-or ellagi-) tannin through a carbon-carbon linkage. Since the first demonstration of their natural occurrence, a considerable number of these unique secondary metabolites have been reported. " New additions (Table 11.17) to this series of compounds come exclusively from the groups of Nonaka and Nishioka, and Okuda and Yoshida in Japan. 

Apart from some plant and fungal secondary metabolites, the occurrence of oxazole ring system in nature is rather limited. However, the following antiinflammatory drug contains an oxazole ring system. 

The natural occurrence of oxygen heterocycles is well documented (B-63MI22400) and almost every category of the compounds discussed in the earlier sections provides examples of secondary metabolites. A discussion of their biosynthesis is therefore appropriate. 

Polyphenolic phytochemicals are ubiquitous in the plant kingdom. These important aromatic secondary metabolites of plants are consumed in significant amounts in daily life. Their occurrence among plant-based materials is frequently varied. They contribute to sensory qualities such as color, flavor, and taste of plant-based materials. The composition of polyphenolic phytochemicals is influenced by maturity, cultivar (Lee and Jaworski, 1987), cultural practices, geographic origin, climatic... 

Hydroxamic acids are commonly occurring secondary metabolites in cultivated and wild Gramineae.16,27,43 This family of compounds has not been found in cereal seeds, but they can be detected easily in seedlings and mature plants of cereals such as wheat, corn or rye.3 The presence of these compounds is species dependent and is also influenced by the age of the plant, temperature, photoperiod and organ assayed.4,14,19 Their occurrence has been broadly related with the resistance of cereals (corn, wheat, wild rye, giant reed, etc) to insects and disease organisms. 1... 

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