Flavonoids anthocyanins

Because of its importance, the application of planar chromatography for the analysis of various secondary metabolites in plants such as heterocyclic oxygen compounds (coumarins, flavonoids, anthocyanins, etc.) has been reviewed many times [143,144],... 

Besides the great pigment classes such as carotenoids, flavonoids, anthocyanins and chlorophylls a wide variety of other pigments have been separated, quantitated and identified by different liquid chromatograpchic techniques. The chemical structures of these pigments show high diversity. Unfortunately, in the majority of cases the biological activity of these... 

Aromatic Amino Acid Biosynthesis. The shikimate pathway is the biosynthetic route to the aromatic amino acids tryptophan, tyrosine and phenylalanine as well as a large number of secondary metabolites such as flavonoids, anthocyanins, auxins and alkaloids. One enzyme in this pathway is 5-enolpyruvyl shikimate-3-phosphate synthase (EPSP synthase) (Figure 2.9). 

In addition to organic dyes, natural dyes extracted from plants can be used as photosensitizers [36,140,141]. A nanocrystalline 2 solar cell using a san-talin dye extracted from red sandalwood can produce 1.8% efficiency under 80 mW/cm2 irradiation [141]. Cherepy et al. reported that a nanocrystalline 2 solar cell using flavonoid anthocyanin dyes extracted from blackberries could convert sunlight to electrical power with an efficiency of 0.6% (Jsc = 1.5-2.2 mA/cm2 and Voc = 0.4-0.5 V) under AM 1.5 [36]. 

Many alkaloids, NPAAs, saponins, glycosides, flavonoides, anthocyanins, tannins, cyanogens, glucosinolates, amines... 

Flavonoids Anthocyanins Cyanidin (71), Pelargodin (72) Many sp. HSV Virucidal [12]... 

Like other flavonoids, anthocyanins are also expected to have antioxidant and antimutagenic properties in vivo, although only limited data are available. From the published data, it appears that anthocyanins can be effective in vivo as antioxidants when included in the diet at 1 or 2g/kg diet in animal experiments. These levels in the diet provide 20 to 40 mg per day, levels that are much higher on a body-weight basis than found in the typical diet of humans. " ... 

Fig. 57.12 Schematic representation of the intermolecular copigmentation between anthocyanins and flavonoids. (—), anthocyanin (—), flavonoids [170]...

The chemical nature of plant phenolics varies from simple molecules (phenolic acids) to complex polyphenols such as flavonoids, anthocyanins, and highly polymerized substances that include varying proportions of phenolic acids, phenyl propanoids, anthocyanins, and tannins, among others [3,16-18],... 

Kirchner (1978) has discussed the utility of thin-layer chromatography for the following natural pigments chlorophylls, carotenoids, xanthophylls, flavonoids, anthocyanins, porphyrins, and bile. From the standpoint of practical TLC, the most important of these pigments are the chlorophylls, carotenoids, xanthophylls, and anthocyanins, and it is these pigments that are considered further in this chapter. For practical TLC of the flavonoids, consult Harbome (1984, 1992). For information on the TLC of porphyrins, see Doss (1972), Dolphin (1983), and Jacob (1992). Jain (1996) has provided useful information on the examination of porphyrins (in studies on clinical porphyrias) by TLC in clinical chemistry. 

Isaksen (1991) provided an extensive review on the TLC of natural pigments. He stated that TLC is the most common method used to analyze natural pigments. Pigments considered by Isaksen include the flavonoids, anthocyanins, carotenoids, chlorophylls, chlorophyll derivatives, and porphyrins. Optimal chromatographic systems (i.e., sorbents and mobile phases for each pigment group) are considered in detail in the review. The Isaksen (1991) review was revised and updated by Andersen and Francis (1996). 

Non-nucleotide pol inhibitors have been discovered among different classes of namral and synthetic chemical compounds. The main of them are long-chain fatty acids, fatty acid derivatives, bile acid derivatives, steroid derivatives, triterpenoids, cerebrosides, alkaloids, flavonoids, anthocyanins, glycolipids, catechins, coenzyme Qs, isosteviols, dipeptide alcohols, vitamins, etc. [52, 53]. The most well-studied non-nucleotide inhibitors are presented in Table 4.2. 

In this section the thin-layer chromatographic properties of phenolic compounds as revealed by their / /Values are given. The first part covers essentially the substituted derivatives of monocyclic phenols, the second part is concerned with phenolic acids (with their derivatives), and the final one with more complex phenolic compounds such as phenolic glycosides, flavonoids, anthocyanins, lignan derivatives, phenolic steroids, cannabinoids, and other types. Some overlap between subsections is inevitable, but this feature serves incidentally to interrelate the thin-layer chromatographic properties of phenolic compounds as a whole. The material in the last section has been dealt with in other monographs (1), and more emphasis has been placed in this review on substituted phenols and phenolic acids and their simple derivatives. 

A great number of phenolic compounds, including yellow flavonoids, anthocyanins, the ellagic, gallic and p-coumaric acids, as well as quercetin, myricetin, and kaempferol derivatives have been identified in the cashew apple (Michodjehoun-Mestres etal. 2009 Hoffinann-Ribani et al. 2009 Brito et al. 2007 Moura et al. 2001), while condensed tannins and anacardic and ascorbic acids have been identified in cashew juice and cajuina. It is also known that cashew apple skins are 15-20 times richer in total phenolic compounds than their flesh (Michodjehoun-Mestres et al. 2009). In addition, lutein, zeinoxanthin, cis- and tra s -P-cryptoxanthin, a-carotene and p-carotene cis and trans) were identified as the major carotenoids present in three different varieties of ripe cashew apple (elongated yellow, elongated red, and rounded red) (Assunfao a/. 2003). 

Divided into 10 chapters, this book gathers updated, in-aepth treatments of the methods of analysis for phytoestrogens, fatty acids and conjugated linoleic acid, flavonoids, anthocyanins, carotenoids and provitamin A, chlorophylls, water soluble vitamins, amino acids, and carbohydrates. It also includes specialty information such as the use of residues from vineyards and oil production for phenolic compounds. 

---