Adsorption of Flavonoids on Resins:  Cyanidin 3-Glucoside

Abstract

Adsorption of cyanidin-3-glucoside in aqueous batch solutions was studied at pH 3.5 and 20 degrees C using 13 commercial resins with different hydrophobicity, surface areas (SA, 330-1200 m2/g), and pore radii (PR, 20-260 A). The solute affinity toward different resins was described in terms of Langmuir and Freundlich parameters; experimental data were well-fitted to the two isotherms, which were both utilized to compare resins adsorption capacity. The styrene-divinylbenzene EXA-118 resin (SA, 1200 m2/g; PR, 90 A) showed the maximum effectiveness among the tested resins; a good efficacy for removing cyanidin 3-glucoside was shown also by EXA-90 (SA, 630 m2/g; PR, 105 A). Some experiments on a styrene-divinylbenzene resin and an acrylic one demonstrated that adsorption was not influenced by pH variations of the solution within the range of 1.0-4.5. For the 10 resins having PR < or = 105 A, correlation analysis evidenced the linear increasing dependence of Freundlich constant KF on physical characteristics of surface area and pore radius. The adsorption of cyanidin 3-glucoside at 20 degrees C was compared with that of hesperidin performed in batch runs on the same resins. Moreover, the best resin (EXA-118) was tested with a sample of pigmented orange juice to assess its performance in terms of selectivity, adsorption, and desorption capabilities on a real matrix.

Phytochemicals from berries and grapes inhibited the formation of advanced glycation end‐products by scavenging reactive carbonyls

“…No free sugar was detected by HPLC with refractive index detector in the berry or grape extracts. This was consistent with the capacity of polystyrene copolymer resins to adsorb polyphenols from the aqueous phase but not sugars (Scordino, Di Mauro, Passerini, & Maccarone, 2004).…”

Isolation of polyphenols from the extracts of olive leaves (Olea europaea L.) by adsorption on silk fibroin

“…Since adsorption is a low cost separation technique, it is preferred for the selective recovery of target plant metabolites from the crude extracts [22]. Synthetic adsorbents have been applied for adsorbing valuable polyphenols from plant extracts [23][24][25][26][27][28][29]. Many biopolymers, such as collagen and cellulose have also been used as adsorbents for the recovery of polyphenols and the interaction between the biopolymers and antioxidative polyphenols have been widely investigated [1].…”

Preparative enrichment and separation of astragalosides from Radix Astragali extracts using macroporous resins

“…The Langmuir and Freundlich theoretical equations [23,24] (see Supporting Information) were used to describe the interaction between sorbent and adsorbed material [25][26][27][28]. Adsorption isotherm experiments on SA-3 resin (2 g wet resin) were conducted by bringing into contact seven aliquots of 40 mL sample solutions at different concentrations in a constant temperature shaker, and then shaking at 25, 30 and 351C for 4 h, respectively.…”