Polyphenols stilbenes

Dore S. 2005. Unique properties of polyphenol stilbenes in the brain More than direct antioxidant actions gene/protein regulatory activity. Neurosignals 14 61-70. 

The nonflavonoid polyphenols include the phenolic acids or hydroxybenzoates (basic chemical structure C6-C1), hydroxycinammates (basic chemical structure C6-C3), and polyphenolic stilbenes (basic chemical structure C6-C2-C6). 

Resveratrol is another type of polyphenol, a stilbene derivative, that has assumed greater relevance in recent years as a constituent of grapes and wine, as well as other food products, with antioxidant, anti-inflammatory, anti-platelet, and cancer preventative properties. Coupled with the cardiovascular benefits of moderate amounts of alcohol, and the beneficial antioxidant effects of flavonoids, red wine has now emerged as an unlikely but most acceptable medicinal agent. 

Curcumine S. Mikado yellow, golden yellow and orange, direct yellow, stilbene yellow, diamine fast yellow A, A R diamine orange D, dianil direct yellow S, chloramine orange, naphthamine yellow, diphenyl chrysoine, diphenyl citronine, sun yellow, polar yellow, polyphenol yellow, etc. 

Fig. 1 Biosynthesis of plant polyphenols by CHS-superfamily type III PKSs. CHS chalcone synthase STS stilbene synthase ACS acridone synthase VPS valerophenone synthase SPS styrylpyrone synthase BPS benzophenone synthase OAS olivetolic acid synthase 2PS 2-pyrone synthase BAS benzalacetone synthase CUS curcumin synthase...

Plant-derived products Polyphenols (derivatives of hydroxycinnamic acid, hydroxybenzoic acid, flavonols,3 flavones,3 anthocyanidins,3 flavanols,3 isoflavones,3 flavanones,3 stilbenes, lignans), glucosynolates, carotenoids (am /3-, y-, 8-carotene, lycopene, luthein, xeaxantin, canthaxantin), phytic acid, allicin... 

Polyphenols (PP) represent a very wide variety of about 6000 compounds divided into I I different classes represented by hydroxybenzoic acids, hydroxycinnamic acid, anthocyanidins, flavonols, flavanones, flavanols (divided into monomeric cathechins and polymeric proanthocyanidins3), flavones, isoflavones, stilbenes, and lignans (16). 

It is widely accepted that polyphenols in wine are responsible for beneficial health effects (Sun et al. 2006). Particularly fran.y-resveratrol has been intensively studied and marked biological activities with regard to the prevention of cardiovascular disease and cancer have been reported (Ito et al. 2003). Other stilbenes also have properties similar to those of fran.y-resveratrol. Therefore, monitoring new stilbene derivatives in wine is of particular relevance (Guebailia et al. 2006). 

The polyphenols, i.e. stilbenes such as pinosylvin, in Pinus sp. are considered to be responsible for the better durability of pine heartwood compared to sapwood. The fiavonoid dihydroquercetin is considered to be responsible for the durability of Douglas fir heartwood while tectoquinone, 2-methyl anthraquinone, is responsible for the durability of teak and cedrol contributes to the durability of Chinese fir,... 

Some microbial pathogens can circumvent the defensive response of plants by biotransforming the antimicrobial stilbenoids in a multi-step oxidative detoxification process [106], Research has shown that the pathogenicity of B. cinerea strains is positively correlated with these fungi s production of blue-copper oxidases known as stilbene oxidases or laccases [127,128]. These enzymes are polyphenol oxidases capable of catalyzing the oxidation and polymerization of numerous phenolic substrates [129,130,131,132]. It has been shown that 1 is readily transformed in the presence of B. cinerea culture medium filtrates that contain laccases [107]. Recently, six resveratrol dimers (restrytisols A-C... 

Polyphenols include flavonoids, proanthocyanidins, stilbenes, microbial metabolites of lignan, and hydroxycinnamates (Fig. 2). Flavonoid metabolism, while still far from being fully understood, has been the most widely studied and will therefore form the basis of this chapter. Six main subclasses of flavonoids are widely consumed by humans flavonols, flavones, flavanones, isoflavonoids, flavanols (catechins), and anthocyanins these posses the generic structure shown in Fig. 3. These classes differ in the degree of saturation and the nature and position of reactive groups on their three rings examples of substitution patterns for selected flavonoids are given in Table 1. 

Figure 2 Chemical structures of selected plant polyphenols. Structures include a flavonol (quercetin), isoflavone (daidzein), cinnamic acid (chlorogenic acid), flavan-3-ol (catechin), a lignan microbial metabolite (enterodiol), and a stilbene (resveratrol).

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