Effect of exogenous quercetin on the level of carbohydrates and amino acids in Lycopersicon esculentum fruit
Stakhov, L.F.; Stakhova, L.N.; Ladygin, V.G.
Prikladnaia Biokhimiia i Mikrobiologiia 36(2): 233-237
2000
ISSN/ISBN: 0555-1099 PMID: 10780016 Document Number: 514970
Low doses of the exogenous flavonoid quercetin increased in contents of sugars in tomato fruits of various cultivars. The content of glucose in tomato fruits of cv. Ukrainskii teplichnyi increased from 3.62 to 11.24% per unit dry weight. Increases in the content of glucose were found in all tomato cultivars examined. An analysis of qualitative and quantitative compositions of amino acids showed that their levels were markedly decreased in fruits of quercetin-treated plants. Our studies and data found in the literature suggest that this effect is due to the synthesis of sugars from amino acids by gluconeogenesis. The reverse process of sugar hydrolysis does not occur because exogenous quercetin inhibits the activity of pyruvate kinase.