A bunch of epidemiological studies provides good evidence on the inverse relationship associated with the consumption of fruits and vegetables and the chronic diseases importantly cardiovascular diseases and some types of cancers. After the long years of study on phytomacronutrients, the role of phytomicronutrients such as polyphenols is now highly studied and appreciated in the control of such degenerative diseases. The present study combines the extraction, synthetic and analytical studies on the major polyphenols of citrus fruits, FLAVANONES.Awareness of nutritional and health facts has increased the production of citrus fruits from last few decades. These higher productions generate higher by-products. For their alternative utilisation to have antioxidants rich extracts, the ultrasound-assisted extraction (UAE) of polyphenols especially flavanones from orange (Citrus sinensis L.) peel by using ethanol as afood grade solvent has been proved its efficiency when compared with the conventional method. A central composite design (CCD) approach revealed that the optimized conditions for UAE were a temperature of 40°C, a sonication power of 150W and a 4:1 (v/v) ethanol:water ratio. Furthermore, the antioxidant activity determined by the DPPH and ORAC tests confirmed the suitability of UAE for the preparation of antioxidant-rich plant extracts. Flavanone glucuronides are the major phenolic metabolites detected in human plasma after consumption of citrus fruits. Up to now all cell studies related to cancer or cardiovascular diseases were conducted either on the aglycones or on their glycosides. Hence, there is great need of pure flavanone glucuronides to demonstrate the real potential of flavanones in the prevention of these diseases. In this work, glucuronides of naringenin (4′- and 7-O-β-D-glucuronides) and hesperetin (3′- and 7-O-β-D-glucuronides), the major flavanone aglycones in grapefruit and orange respectively, have been chemically synthesized by selective protection and deprotection of flavanone and glucuronic acid moieties. The complete structural characterisation of purified compounds were realised by nuclear magnetic resonance and mass spectrometry.The affinity of the four glucuronides for human serum albumin (HSA) was tested via their ability to quench the intrinsic fluorescence of HSA (single Trp residue in sub-domain IIA). Their binding constants (K) were estimated in the range of 30 – 60 × 103 M-1 and compared with those of the aglycones (70 – 90 × 103 M-1). Investigations of competitive or noncompetitive binding of the glucuronides in the presence of fluorescent probes (dansyl sarcosine) allowed us to get some insight in the binding sites. The study was also extended to the hesperetin and naringenin chalcones (synthesised using optimized alkaline conditions), which are the biosynthetic precursors of flavanones

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{{Explor lien
   |wiki=    Wicri/Bois
   |area=    OrangerV1
   |flux=    France
   |étape=   Analysis
   |type=    RBID
   |clé=     Hal:tel-00543792
   |texte=   Citrus polyphenols (flavanones) : extraction of glycosides from orange peel, synthesis of metabolites (glucuronides) found in human and a physico-chemical study to investigate their interaction with human serum albumin
}}