Flavanones phloretin

Chalcones and dihydrochalcones have been reported in a restricted number of foods (Robards and others 1999 Tomas-Barbcran and Clifford 2000). Chalconaringenin occurs in tomato skin, but the acid extraction conditions of the usual polyphenol analyses convert the chalcone to the corresponding flavanone (naringenin) in the tomato. The most common dihydrochalcones found in foods are phloretin glucoside (phloridzin) and phloretin xylogalactoside, which are characteristic of apples (see Table 2.2) and derived products such as apple juice, cider, and pomace (Robards and others 1999 Tomas-Barbcran and Clifford 2000). 

B) Inhibition of arachidonic acid metabolism. Most flavonoids tested (flavone, chrysin, phloretin, flavanone, apigenin and kaempferol) inhibited... 

Early work on the formation of cyanidin (19) - , quercetin (14)18-20 (—)-epicatechin (21) and phloretin (23) demonstrated quite clearly the biosynthetic pattern postulated by the Birch-Donovan hypothesis, i.e. ring A of the flavonoids is derived by a head to tail condensation of three acetate (or malonate) units, while ring C and the three carbon chain originate from a phenylpropanoid precursor. All subsequent experimental observations show that chalcones, with their respective isomeric ilavanone, occupy a central position as intermediates in flavonoid biosynthesis. Thus Grisebach and his collaborators have demonstrated the incorporation of appropriately labelled C labelled chalcones flavanones)... 

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