The Flavonoids of Tomatoes

Abstract

Tomatoes ( Lycopersicon esculentum Mill.) have been recognized as an important source of dietary flavonoids because of a high consumption worldwide. The qualitative and quantitative flavonoid compositions of assorted tomato cultivars including individual quantitative contributions of the five most significant flavonoids have been determined in this work. The dihydrochalcone phloretin 3',5'-di-C-beta-glucopyranoside and the flavonol quercetin 3-O-(2''-O-beta-apiofuranosyl-6''-O-alpha-rhamnopyranosyl-beta-glucopyranoside) were identified for the first time in Solanaceae spp. and found to be among the main flavonoids in all cultivars. Phloretin 3',5'-di-C-glc is the first C-glycoside identified in tomatoes and also the first dihydrochalcone from this species. In addition, chalconaringenin, kaempferol 3-rutinoside, and quercetin 3-rutinoside (rutin), though previously reported to occur in tomato, were fully characterized by extensive use of 2D NMR techniques and high-resolution LCMS. The total flavonoid content of different tomato types varied from 4 to 26 mg 100 (-1) g FW with chalconaringenin as the predominant compound comprising 35 to 71% of the total flavonoid content. The individual quantities of quercetin 3-O-(2''- O-beta-apiofuranosyl-6''- O-alpha-rhamnopyranosyl-beta-glucopyranoside) and phloretin 3',5'-di-C-beta-glucopyranoside was similar to that of rutin in several cultivars.

Metabolomics reveals organ-specific metabolic rearrangements during early tomato seedling development

“…2). Flavonoids are important plant secondary metabolites which are known to accumulate in tomato (Slimestad et al 2008). In tomato fruit, three flavonoids are typically present in tomato peel; chalcone, naringenin chalcone as well as the flavonol, quercetin-3-rutinoside .…”

Flavonoid Profiling and Biosynthetic Gene Expression in Flesh and Peel of Two Tomato Genotypes Grown under UV-B-Depleted Conditions during Ripening

“…Nonetheless, the putative identification of tomato metabolites by mass spectrometry was recently proposed by Moco et al (33) as an alternative to isolation and NMR characterization. Moreover, very recently Slimestad et al (34) reported the occurrence in tomato of a quercetin derivative, which was identified as quercetin 3-O-[2′′-O-apiofuranosyl-6′′-O-(R)-rhamnopyranosylglucopyranoside] on the bases of chromatographic (HPLC) and spectral (UV, high-resolution MS, 1 H and 13 C NMR) data. The MS and MS/ MS data obtained in the present work for the quercetin derivative are consistent with those reported by Slimestad et al (34).…”

“…Moreover, very recently Slimestad et al (34) reported the occurrence in tomato of a quercetin derivative, which was identified as quercetin 3-O-[2′′-O-apiofuranosyl-6′′-O-(R)-rhamnopyranosylglucopyranoside] on the bases of chromatographic (HPLC) and spectral (UV, high-resolution MS, 1 H and 13 C NMR) data. The MS and MS/ MS data obtained in the present work for the quercetin derivative are consistent with those reported by Slimestad et al (34). Nonetheless, in the absence of NMR data, we are not able to univocally identify the pentosyl group as apiose; thus we prefer to stick with the more generic name quercetin 3-O-pentosylrutinoside.…”

The Occurrence, Fate and Biological Activities ofC-glycosyl Flavonoids in the Human Diet

“…In one study, chalconaringenin dominated the composition in the skins of 9 cultivars quantified by HPLC-DAD (35 -71%), however the C-glycosyl dihydrochalcone phloretin 3 ,5 -di-C--D-glucoside was found to contribute 5 -14% of the total flavonoid content and was present in all cultivars tested (Slimestad et al, 2008). This is currently the only C-glycosyl flavonoid identified in tomatoes, and indeed is the first dihydrochalcone identified in genus Lycopersicon and family Solanaceae.…”