Flavanones hesperetin

The flavanone hesperetin has been detected in citrus honeys but not in honey samples of any other origins (Ferreres et al., 1993). It is a constitutive phenolic compound of citrus nectar, where it is present as a glycoside (hesperidin). 

Borradaile, N.M., Carroll, K.K., and Kurowska, E.M. 1999. Regulation of Hep G2 cell apolipoprotein B metabolism by the citrus flavanones hesperetin and naringenin. Lipids 34, 591-598. 

Flavonoids stimulate spore germination in the soilborne phytopathogenic fungus Fusarium solani. Spore germination of F. solani f. sp. pisi, which causes disease in pea, is stimulated by flavanone hesperetin (141), flavone apigenin (101), the pterocarpan phytoalexin pisatin (142), and so on. In contrast, germination of the bean pathogen F. solani f. sp. phaseoli is stimulated by the pterocarpans maackiain (143) and medicarpin (129), and isoflavones biochanin A (144), and so on but not by pisatin.85... 

Figure 6.1. Flavonoids shown to be of nutritional significance are, for the most part, derivatives of either flavone or flavanone, e.g. quercetin (3,3,4,5,7-pentahydroxyflavone), rutin (quercetin-3-rutinoside), naringenin (4,5,7-trihydroxy flavanone), hesperetin (3,5,7-tri-hydroxy-4-methoxyflavanone) and hesperidin (hesperetin-7-rutinoside)...

Flavanones Hesperetin, naringenin, eriodictyol Citras fraits and Juices, e.g., oranges, grapefraits, lemons... 

Flavanones Naringenin, hesperetin, Oranges and other citrus fruits... 

Flavanones In some cases, flavanones produced by CHI will accumulate to sizeable amounts instead of being diverted away to form flavonols, anthocyanins, and flavanols (see Fig. 5.4). These flavanone products, hesperetin and naringenin being the most common, are frequently encountered in citrus fruits and juices (USDA Flavonoids Database Release 2.1,2007). In most of these cases, essentially no flavonols or anthocyanins are encountered the flavonoid pathway is essentially blocked at the F3H step. 

Erlund, L, Meririnne, E., Alfthan, G., and Aro, A., Plasma kinetics and urinary excretion of the flavanones naringenin and hesperetin in humans after ingestion of orange juice and grapefruit juice, J. Nutr., 131, 235, 2001. 

The flavanones have received less attention in comparison to flavonols and isoflavones, although their intake from the diet can be high and they exhibit promising biological activity. Little information is available about the absorption or the kinetic behavior of the flavanones naringenin, hesperetin and their glycosylated forms naringin, hesperidin, and narirutin. 

Flavanones are mainly represented by naringenin, hesperetin, and eriodictyol, while a number of minor compounds, including sakuranetin and isosakurane-tin, also occur (Fig. 1.15). Two structural features—the absence of a A2 3 double... 

As previously mentioned, certain flavonoids can penetrate into the hydrophobic core of membranes, a feature that mainly relies on their hydrophobic character, which is dictated by flavanoid chemical structure and spatial conformation. When flavonoid hydrophobicity was assessed from the partition coefficient between ra-octanol and an aqueous solution, the following order of hydrophobicity was observed flavone, genistein > eriodictyol, myricetin, quercetin, kaempferol, hesperetin, daidzein > > galangin, morin, flavanone, naringenin, taxifolin (Table 4.1). 

Baeyer-Villiger rearrangement of flavanone derivatives with MTO/H2O2 was first reported in 2001 by Saladino and coworkers and has successfully been applied for various substituted flavanones (Scheme 14). In the case where R1, R2, and R3 are methoxy groups (naringenin) or when all R-groups are methoxy groups (hesperetin), oxidation toward the benzoquinone product is the major product... 

Hesperetin (= Eriodictyol 4 -methyl ether 5,7,3 -Trihydroxy-4 -methoxy-flavanone) (flavanone)... 

Hesperidin (= Ciratin Hesperetin 7-0-Rut 5,7,3, 4 - Tetrahydroxy-flavanone 4 -methyl ether 7-0-Rha-Glc) (flavanone glycoside)... 

Although the search for enzymes to convert flavanone glycosides to dihydrochalcones has not been successful (195) and the chemical conversion is facile (193, 196), several possibilities for enzymatic modification exist besides conversion of hesperidin to hesperetin-7-glucoside. Conversion of naringin (or its dihydrochalcone) to neohesperidin (or its dihydrochalcone) by enzymatic hydroxylation and chemical methylation and enzymatic rhamnosylation of hesperetin-7-glucoside or its dihydrochalcone at the 2 position (197) would yield neohesperidin dihydrochalcone. 

---