||(-)-3,5,7,3',4'-PENTAHYDROXYFLAVAN; 3,5,7,3',4'-PENTAHYDROXYFLAVAN; 3,3',4',5,7-PENTAHYDROXYFLAVAN; 3,3',4',5,7-PENTAHYDROXY-FLAVANE; 3,3',4',5,7-PENTAHYROXYFLAVONE; (2R,3R)-2-(3,4-DIHYDROXYPHENYL)-3,4-DIHYDRO-1(2H)-BENZOPYRAN-3,5,7-TRIOL
1.Effect of the addition of flavan-3-ols on the HPLC-DAD salivary-protein profile.
Quijada-Morín N1, Crespo-Expósito C2, Rivas-Gonzalo JC3, García-Estévez I4, Escribano-Bailón MT5. Food Chem. 2016 Sep 15;207:272-8. doi: 10.1016/j.foodchem.2016.03.118. Epub 2016 Mar 30.
The interaction between monomeric flavan-3-ols and salivary proteins has been studied using HPLC-DAD. A chromatographic method has been described and seven protein fractions were collected. The peptides and proteins present in each fraction have been identified using nLC-MS-MS analysis. The interaction between saliva and catechin, epicatechin and gallocatechin has been studied. These compounds interact in a discriminated way with salivary proteins: catechin causes a decrease of some fractions, epicatechin causes the decrease or increase of fractions while gallocatechin seems to cause an increase of two fractions. This variable behavior is explained, for the decrease in the chromatographic area, by the precipitation of salivary proteins and, for the increase of the area, by the formation of soluble complexes and/or for the formation of new peaks.
2.Optimization extraction conditions for improving phenolic content and antioxidant activity in Berberis asiatica fruits using response surface methodology (RSM).
Belwal T1, Dhyani P1, Bhatt ID2, Rawal RS1, Pande V3. Food Chem. 2016 Sep 15;207:115-24. doi: 10.1016/j.foodchem.2016.03.081. Epub 2016 Mar 23.
This study for the first time designed to optimize the extraction of phenolic compounds and antioxidant potential of Berberis asiatica fruits using response surface methodology (RSM). Solvent selection was done based on the preliminary experiments and a five-factors-three-level, Central Composite Design (CCD). Extraction temperature (X1), sample to solvent ratio (X3) and solvent concentration (X5) significantly affect response variables. The quadratic model well fitted for all the responses. Under optimal extraction conditions, the dried fruit sample mixed with 80% methanol having 3.0 pH in a ratio of 1:50 and the mixture was heated at 80°C for 30min; the measured parameters was found in accordance with the predicted values. High Performance Liquid Chromatography (HPLC) analysis at optimized condition reveals 6 phenolic compounds. The results suggest that optimization of the extraction conditions is critical for accurate quantification of phenolics and antioxidants in Berberis asiatica fruits, which may further be utilized for industrial extraction procedure.
3.Microbial biotransformation of polyphenols during in vitro colonic fermentation of masticated mango and banana.
Low DY1, Hodson MP2, Williams BA3, D'Arcy BR4, Gidley MJ5. Food Chem. 2016 Sep 15;207:214-22. doi: 10.1016/j.foodchem.2016.03.108. Epub 2016 Mar 30.
Mango and banana cell structures, which survived in vivo mastication and in vitro gastrointestinal digestion, were fermented in vitro for 48h. For both fruits, flavonoids and phenolic acids were liberated and underwent microbial metabolism involving ring fission, dehydroxylation and decarboxylation. UHPLC-PDA/Q-ToF-MS profiles revealed rapid degradation (72-78%) of most intact precursors (epicatechin and several unidentified compounds) within 10h, before the exponential phase of the cumulative gas production. Concomitant formation of catabolites (e.g. 4-hydroxyphenylacetic acid) occurred within 4-8h, while metabolism of catechin derivative and 3-(4-hydroxyphenyl)propanoic acid continued slowly for at least 48h, suggesting intact plant cell walls can be a controlling factor in microbial susceptibility. Untargeted PCA and OPLS-DA demonstrated clear classifications in the compositional fruit type and compound profiles as a function of time.
4.Integrated chemometric fingerprints of antioxidant activities and HPLC-DAD-CL for assessing the quality of the processed roots of Polygonum multiflorum Thunb. (Heshouwu).
Chen HF1, Chen YH2, Liu CH2, Wang L2, Chen X2, Yu BY3, Qi J3. Chin Med. 2016 Apr 12;11:18. doi: 10.1186/s13020-016-0087-8. eCollection 2016.
BACKGROUND: The processed roots of Polygonum multiflorum Thunb. (Heshouwu; processed HSW) are commonly used in anti-aging medicine. Few reports have combined chemical profiles with bioactivity to evaluate the quality of the processed HSW. This study aims to integrate chemometric fingerprints of antioxidant activities and high-performance liquid chromatography-diode array detection-chemiluminescence (HPLC-DAD-CL) to assess the quality of processed HSW.