In grapevine, flavonoids constitute one of the most abundant subgroups of secondary metabolites, influencing the quality, health value, and typicity of wines. Their synthesis in many plant species is mainly regulated at the transcriptional level by modulation of flavonoid pathway genes either by single regulators or by complexes of different regulators. In particular, bZIP and MYB factors inter...

Lysimachia laxa is a perennial herb belonging to the family Primulaceae and Gymnocladus assamicus is a critically endangered species of the family Caesalpinioideae contain biologically active substances. The present investigation deals with the evaluation of antioxidant activity of the different parts of these two plants and to determine the best solvent for extracting the antioxidant component...

Dioxygenase, Flavonoid Biosynthesis, Flavonols, Genetic Control, Petunia hybrida Soluble enzyme preparations from flower buds of Petunia hybrida catalyzed the conversion of dihydroflavonols to flavonols. Dihydrokaempferol and dihydroquercetin were readily converted to the respective flavonols, whereas dihydromyricetin was a poor substrate. The reaction required 2-oxoglutarate, ascorbate and Fe2...

We report here a negative ionization nanoelectrospray ionization mass spectrometry (nanoESI-MS) technique that simultaneously detects active components, terpenes and intact flavonol glycosides, and toxic ginkgolic acids in ginkgo products. Unlike the conventional methods that hydrolyze flavonol glycosides to flavonoids for analysis, this technique directly detects intact flavonol glycosides, en...

A rapid microwave-assisted hydrolysis (MAH) method is presented for the sample pretreatment of the determination of ginkgo flavonol glycosides in extracts of Ginkgo biloba L. (EGb). By this method, flavonol glycosides can be completely hydrolyzed within 2 min. After investigating the effects of solvents, acidity, microwave power, and microwave radiation time on hydrolysis, the optimal hydrolysi...

Increased serum uric acid is known to be a major risk related to the development of several oxidative stress diseases. The aim of this study was to investigate the effect of parsley, quercetin and kaempferol on serum uric acid levels, liver xanthine oxidoreductase activity and two non-invasive biomarkers of oxidative stress (total antioxidant capacity and malondialdehyde concentration) in norma...

Background & Aim: This experiment was conducted to examine the effect of different levels of Echinacea purpurea (EP) in comparison with an antibiotic (flavofosfolipol) on total antioxidant activity (AOA) in serum of broiler chicks. Experimental: In this trial 240 one-day-old broiler chicks (Ross 308) were weighed and randomly assigned to the 5 treatment groups, each with 4 re...

Increased serum uric acid is known to be a major risk related to the development of several oxidative stress diseases. The aim of this study was to investigate the effect of parsley, quercetin and kaempferol on serum uric acid levels, liver xanthine oxidoreductase activity and two non-invasive biomarkers of oxidative stress (total antioxidant capacity and malondialdehyde concentration) in norma...