Flavonoids have been studied extensively because they offer great potential health benefits. In thisstudy, enzymatic hydrolysis of glycosylated quercetin, kaempferol, and naringin was used to obtaintheir sugar-free aglycones. The investigation also employed a validated HPLC method to obtain thechiral disposition of the aglycone naringenin enantiomers. These analyses were conducted on exocarp,mesocarp, and seed cavity tissues of field-grown tomato (
Lycopersicon esculentum Mill.) mutants(
anthocyanin absent,
atroviolacea, and
high pigment-1) and their nearly isogenic parent (cv. AilsaCraig) at immature
green, "breaker", and red ripe maturity stages. Concentrations of all flavonoidsusing enzymatic hydrolysis were significantly higher than previously reported concentrations usingacid hydrolysis. Presumably, this occurred due to a more specific and rapid hydrolysis of the glycosidemoiety by the
-glucosidase enzyme. The glycoside
S-naringin was the predominant enantiomer inall fruit tissues, although the aglycones free
R- and
S-naringenin were detected in both exocarp andmesocarp. Whereas there was significantly more quercetin than kaempferol in exocarp tissue, theywere present in about equal concentrations in the mesocarp. Quercetin concentrations were higherin the exocarp and mesocarp of immature
green and breaker fruit of the
high pigment-1 mutant thanin the other genotypes, supporting the observed photoprotection and potential health benefits of the
high pigment-1 tomato genotype.Keywords: Quercetin; kaempferol; naringenin; naringin; enantiomer; maturity stage; HPLC; enzymatichydrolysis